key: cord-0006390-oxzi0b17
authors: nan
title: 38(th) EUROPEAN SOCIETY OF NEURORADIOLOGY Diagnostic and Interventional ANNUAL MEETING
date: 2015-08-27
journal: Neuroradiology
DOI: 10.1007/s00234-015-1557-x
sha: a6ffa0d4616aafbe26cb1e354fa20d3a942eb267
doc_id: 6390
cord_uid: oxzi0b17

nan

In 2008 the Executive Committee of the ESNR decided to introduce two new scientific prizes, alongside the existing Lucien Appel Prize of the ESNR, which is awarded annually to reward the achievements of young neuroradiologists. These new Awards have been created in honour of the Founders of European Neuroradiology, and are presented for the best works in diagnostic and interventional neuroradiology, respectively.

In 2012, the Executive Committee of ESNR decided to give the name of one of the founders of the society, and the name of one of the pastpresidents for the two Awards of the Founders of European Neuroradiology, in an order as "ESNR Awards in Honor of" and to present their short CV and pictures at the Awards Ceremony during the ESNR Annual Congress or during the Symposium Neuroradiologicum.

Among those awards, the proposal of Springer as "ESNR-Springer Award" was also accepted. 1000 € will be awarded by Springer to the "first (ESNR's Full, Associate, Junior or Institutional Member) author of most cited manuscript published in the previous two years from January to December". Citations of the manuscripts will be obtained from SCI on first workday of September, at 17.30 of each year".

Article 1: The three prizes reward the achievements of young scientists, under the age of 40 years, working in the field of neuroradiology in a European center and having been accepted as Full, Associate, Junior or Institutional Member of the ESNR.

Article 2: The prizes, each to the amount of € 2500, will be awarded every year during the Annual Congress of the ESNR or during the Symposium Neuroradiologicum, when applicable.

Article 3: The candidates must be the principal investigator, first author or the last author (principal investigator as evidenced by supporting publications) of an original work in the fields of research in neuroradiology, diagnostic or interventional. Applications can be done for the researches or thesis; a. published in a peer review scientific journal listed in SCI within the last 12 months before the date of submission b. submitted, still unpublished c. not submitted d. defended or not e. must not have received any other prize for the same work

Article 4: All submissions must be in English and should include:

• an application letter • the scientific work to be submitted • the full Curriculum Vitae of the candidate These must be submitted as electronic documents attached to an e-mail to the address below. Please note that each submitted article and its relevant images should be included in a separate attachment. By submitting the work the author agrees, if declared the winner, to present the work at the next ESNR Annual Congress or Symposium Neuroradiologicum.

Article 5: Multiple submissions may be entered by a single author, only when in the judgement of the Scientific Awards Committee these clearly deal with different topics.

Article 6: Entries by candidates who have received ESNR Scientific Awards in previous years are not eligible for submission.

Article 7: Authors are requested to indicate to which of the three awards categories each scientific paper is addressed. If the Scientific Awards Committee considers another category to be more appropriate the submission may be re-classified in consultation with the author.

Article 8: A Scientific Jury will assess and rate the submitted papers. The Jury is composed of the members of the Scientific Awards Committee, plus four internationally-known specialists in neuroradiology.

Article 9: The Scientific Award Committee will designate the laureates after the assessment of the jurors have been received, as a rule by July 1st. If the Committee decides that in any category no submission meets its qualification requirements, no prize will be awarded in that category.

Article 10: All candidates will be notified in writing of the results of the assessment. The laureates will be invited to give a six-minute oral presentation at the Award Ceremony at the ESNR Annual Congress or Symposium Neuroradiologicum. The names of the laureates as well as the titles and abstracts of their scientific works will be placed on the ESNR website and published in the society pages of Neuroradiology. The winning papers, if still unpublished, will be submitted for publication in "Neuroradiology", the official ESNR journal.

The European Society of Neuroradiology holds each year a scientific congress at a place and date designated by the Executive Committee. On the day before the congress, Advanced Courses in Diagnostic Neuroradiology and Interventional Neuroradiology are organized in parallel sessions. The business meeting (General Assembly) of the Society is held in conjunction with this annual scientific congress.

Since its creation in 1969, the ESNR has organized 38 annual congresses. This year the 22 nd Advanced Course in Diagnostic Neuroradiology and the 6 th Advanced Course in Interventional Neuroradiology will be held on the day before the congress. In recognition of the importance of the Symposium Neuroradiologicum, which is held every four years, no scientific congress of the ESNR is held when the Symposium takes place in Europe. The European Course in Neuroradiology

The European Course in Neuroradiology has been a story of success ever since the first course in Toulouse in 1984. More than 1000 young neuroradiologists have completed the cycle of three courses over the past 21 years. The ECNR was conceived as a means to create a common and shared culture, common meeting points and a common standard of knowledge. The form that was adopted and used for the coming 6 cycles, each consisting of three courses, included the major bodies of knowledge as described by the headlines; intracranial nervous system, the spine and spinal cord and the base of the skull, maxillofacial and head and neck neuroradiology.

The ESONR -European School of Neuroradiology -is the most important and complete training programme organized by the ESNR -European Society of Neuroradiology within the main frame, and in partnership with, the ESOR -European School of Radiology. The purpose of this training and education program is based on the vision of what the ESNR considers the range of competences and skills that are the basis of a high qualified neuroradiological activity. The program is designed to offer a pathway to reach such professional and cultural levels. The final points will be the examinations to be certificated at the different levels and in the different branches of this discipline.

Courses are organized at 3 different levels: The Pierre Lasjaunias ECNR is the fundamental Neuroradiology course aimed at neuroradiologists, established or in training. It is based on cycles of four courses (modules), each lasting five days, dedicated to diagnostic and interventional neuroradiology. The full cycle is considered complete after the attendee has participated in all four modules, which can be done in a single cycle or in different cycles. The scientific content of the course is determined by the E d u c a t i o n C o m m i t t e e o f t h e E u r o p e a n S o c i e t y o f Neuroradiology, taking into account international standards and guidelines for training in diagnostic and interventional neuroradiology. The participating educators will be internationally renowned European experts, to be selected on the basis of their scientific background and educational skills to ensure highquality lectures and interactive case discussions.

The following topics have been chosen, each to be covered in five full days of lectures and workshops:

• Anatomy, congenital malformations and genetics. 8. 00-8.20 Cerebral Microbleeds and Cerebral Amyloid Angiopathy Rolf Jäger (UK) 8. 20-8.40 MR contribution to diagnosis and differential diagnosis in dementia Frederik Barkhof (The Netherlands) 8. 40-9.00 Imaging in Parkinsonism and other extrapyramidal disorders Tatjana Stošić Opinćal (Serbia) 9. 00-9.20 Role of PET in the diagnosis and differential diagnosis of MD Timo Krings (Canada) 10. 50-11.10 Optical flow measurement for in-vivo aneurysmal flow characterization Timo Krings (Canada) 11. 10-11.30 ASL principles and application Pedro Vilela (Portugal) 11. 30-11.50 Update on haemodinamic of intracranial aneurysms

Zsolt Kulcsár (Switzerland) 11.50-12.00

Question time 12.00-13.00 Diagnostic Special Focus in MS ESNR MAGNIMS Joint Session Chairs: Frederik Barkhof (The Netherlands), Alex Rovira (Spain) 12. 00-12.20 Update on MR Imaging features in multiple sclerosis Alex Rovira (Spain) 12. 20-12.40 Pediatric MS: which are the distinguishing characteristic? Mike Wattjes (The Netherlands) 12. 40-13.00 Clinical relevance of brain atrophy in MS Frederik Barkhof (The Netherlands) 16.50-17.10

The fetal spine: how to study and what to look for Nadine Girard (France) 17. 10-17.30 Spinal malformations: patterns recognition Andrea Rossi (Italy) 17. 30-17.50 The hyperintense spinal cord: pattern recognition Chen Hoffmann (Israel) 17. 50-18.10 Pitfalls, variants and non-patological findings Thierry Huisman (USA) 18. 10-18.30 Question Time Acute ischemic stroke represents a growing disease, with a high mortality and morbidity. The recent published trials about endovascular treatment of acute ischemic stroke concluded reporting significant results in terms of clinical improvement and functional outcome. Although the introduction of the stent-like retrievers for Mechanical Thrombectomy has been considered a breakthrough in the endovascular treatment of acute ischemic stroke, the higher recanalization rates are not linearly followed by increased rates of favorable clinical outcomes, that is the issue of the "futile recanalization". Therefore, a growing attention has been paid to the patients selection. The use of multimodality CT (with associated CT-A and CT-Perfusion), the use of MR, the developing importance of collaterals moved the concept of therapeutic window from a rigid temporal criteria to a biological one, modifying also the indications to both endovascular treatment and i.v. r-tPA administration.

Intracerebral hemorrhage (ICH) is more common in males, blacks and Asians and alcoholics accounting for 52,000 hospital admissions per year in the USA. Despite advances in ICU care, mortality is stable and is about 30%. 50% of all patients die in day one and 60% in the first month. 80% of survivors have disabilities. In adults, excluding trauma, the most common cause is hypertension followed by amyloid in the elderly. Genetic causes are found in 40% of hypertension-related bleeds, 70% in amyloid, and up 50% of bleeds due to cavernomas. In presence of AVMS, only patients with HHT harbor a genetic component. MRI risk markers include mainly microbleeds (identified on SWI) which are seen in up to 80% of ICH patients. Microbleeds due to hypertension occur predominantly in the central brain (basal ganglia and thalami) and central cerebellum (dentate nuclei). ICH is a dynamic process characterized by expansion (40%) and edema. ICH leads to BBB disruption, local coagulopathies, inflammation, and ischemia. Both CT and MRI are 100% sensitive in the detection of ICH. Both modalities can identify the "spot" and "swirl" signs which portray a poor prognosis and signify active bleeding and/or underlying lesions. Cerebral amyloid angiopathy (CCA) is characterized by posterior and cortical microbleeds, SAH (central type), siderosis, and large ICH. Damage to the wall of the subarachnoid and cortical arteries is responsible for its clinical manifestations.

Nadine Girard (France) The lecture on pediatric emergencies will be focused on the primary indications of neuroimaging in children. Head trauma will not be covered. Neuromimaging is discussed in the context of febrile and non febrile convulsions, ataxia, intracranial hypertension, coma, stroke with some differential diagnoses because stroke is rare in children.

10.45-13.00 Session 2

PRES (Posterior reversible encephalopathy syndrome) is described neurological condition identifiable by clinical and radiological presentation. It occurs due to elevated blood pressure which exceeds auto-regulatory capacity of brain vasculature. PRES is characterized by headache, confusion, seizures, and altered mental function. and visual disturbances, as well as radiologic findings of focal reversible vasogenic edema, best seen on magnetic resonance imaging (MRI) of the brain. The syndrome is most commonly encountered in association with acute hypertension, preeclampsia or eclampsia, renal disease, sepsis, and exposure to immunosuppressants. IRIS (Immune reconstitution inflammatory syndrome) is an "unmasking" or paradoxical worsening of a pre-existing infection after commencement of highly active antiretroviral therapy (HAART) in human immunodeficiency virus (HIV) -infected patients. While this reaction can range from mild to fulminating, encompassing a very wide clinical spectrum, it is important to recognize because changes in medical management may be necessary to prevent neurologic decline and even death. CNS-IRIS is a diagnosis of exclusion, the neuroradiologist can play a critical role in alerting the clinician to the possibility of this syndrome. RCVCS (Reversible cerebral vasoconstriction syndrome) is characterised by acute and severe headaches, with or without other acute neurological symptoms, associated with diffuse segmental constrictions of cerebral arteries that resolve spontaneously within 3 months. The physiopathology of RCVS seems to involve genetic features, endothelial dysfunction, and variation of the adrenergic cerebral tone.

Acute white matter autoimmune diseases can affect both young and elderly individuals. It includes different entities as for example: acute disseminated encephalomyelitis (ADEM), an autoimmune disease marked by widespread attack of inflammation in the brain and spinal cord often triggered after a viral infection or vaccination. Symptoms and findings often presents 1-3 weeks after infection and presents with typical subcortical and central white matter lesions, as well as in the gray-white matter junction but can also be seen in cortex, basal ganglia, thalami and in periventricular white matter and in the spinal cord. Multiple sclerosis (MS) is a common autoimmune disorder affecting the white and gray matter of the brain and spinal cord. In the acute setting the lesions might demonstrate contrast enhancement and restricted diffusion on MR imaging. Guillain-Barré syndrome is an autoimmune disorder occurring after an infection; gastroenteritis, respiratory tract infection or campylobacter jejuni infection. The disease affects predominately the periphery nervous system but lesions in pons, midbrain and brainstem are not unusual. Another disease that can present with acute CNS involvement is Systemic lupus erythematosus (SLE) a systemic autoimmune disease that when involving the CNS present with neurological symptoms like fatigue, mental confusion or even coma. MRI is the method of choice to evaluate possible changes in the brain such as abnormal white matter lesion, pathological contrast enhancement, vasculitis changes and even ischemia and focal infarcts. The lecture will present imaging findings in different autoimmune diseases.

Drug abuse is a substantial problem in society and is associated with significant morbidity and mortality. It's an epidemic that crosses racial, socioeconomic, and age barriers. According to the 2015 Global Drug Survey most popular drugs include alcohol, cannabis, and tobacco. However, the use of amphetamines (e.g. XTC) and cocaine is on the rise, especially in young adults. Various drugs may cause central nervous system (CNS) complications. These complications include acute and chronic neurovascular complications, (toxic) leukoencephalopathy, atrophy, infection, changes in the corpus callosum, and other miscellaneous changes. Neurovascular complications constitute the most frequent drug related emergencies. They include both ischemic stroke, subarachnoid and intracerebral hemorrhage. Multiple drugs are associated with neurovascular complications (heroin, amphetamines, …) but cocaine is the hallmark drug. Mechanisms of action contributing to cocaine-related ischemic strokes include direct vasospasm, enhanced platelet aggregation, cardioembolic sources, accelerated atherosclerosis, and cerebral vasculitis. Heroin-associated infarcts often involve the globus pallidus; 5%-10% of users have pallidal infarcts at presentation. In cases of intranasal cocaine administration, hemorrhagic complications are twice as common as ischemic stroke. Subarachnoid hemorrhage may be found as a result of aneurysm rupture, since 40%-50% of patients have aneurysms and arteriovenous malformations. Intraparenchymal hemorrhage is often located in the basal ganglia and thalamus. Also reperfusion hemorrhage from ischemic stroke may be observed, with increased risk of hemorrhage after concomitant use of cocaine with alcohol. Also prescribed medications (antibiotics, antiepileptics, …) or medical therapies (immunosupressants, chemotherapy, total parenteral nutrition, … can affect the CNS. A typical complication observed in patients under immunosupressants is posterior reversible encephalopathy syndrome (PRES).

Acute and subacute visual disturbances can be secondary to vascular, tumoral/compressive, inflammatory, infectious and toxic causes. Visual loss can be acute or subacute and be associated with other symptoms and signs like pain or diplopia. A very precise clinical indication is fundamental for the choice of imaging protocol and to improve its diagnosis value. The features of visual field defect are particularly relevant to define the site and hence the possible pathogenetic causes. MRI is the modality of choice for the study of the visual pathways. Exceptions are those conditions such as head injury with visual loss in which CT is the first imaging procedure. Contrast enhancement is important in assessing most orbital disorders. MRI imaging protocol must be adapted to the area involved by the pathology; lesions affecting optic nerve in the orbital compartment must investigated using fat-sat sequences sequences in order to reduce the interference coming from orbital fat. Pathologic conditions involving intracranial optic nerve, chiasm, optic tracts must be focused on the sellar and parasellar area, including parenchimal and vascular structures therein located. Geniculate and retrogeniculate optic pathways alterations must be studied considering the adjacent brain structures. During the presentation, a topographic approach starting from the head of the optic nerve will be followed trying to give more emphasis to the most frequent diseseas encountered during the clinical activity, like inflammatory conditions such as optic neuritis, or ischemic causes due to cerebrovascular disorders or vasculitis. At the mean time, less common condition due to infections or toxicity will be discussed.

Hydrocephalus is an abnormal buildup of cerebrospinal fluid (CSF) in the ventricles of the brain, in which the fluid is often under increased pressure and can compress and damage the brain. According to the CSF bulk flow theory, hydrocephalus is caused by an imbalance between CSF formation and absorption, or a block at various locations in the major CSF pathway. Many theories on CSF dynamics in relation to hydrocephalus have been postulated, leading to different classification from that of communicating and noncommunicating (based on Dandy's theory), through that of nonobstructive and obstructive (Russell's theory), to the last multicategorical hydrocephalus classification (McHC), which involves eight different categorical sections, including cause, pathophysiology, and occurrence of shunt placement. Hydrocephalus may be due to many causes including birth defects, hemorrhages, infections, meningitis, tumors, head injuries, etc. Independently from the cause, acute hydrocephalus represents a clinical emergency, that requires prompt recognition/ therapy. In this scenario neuroimaging plays a key role from the identification, to the definition of the cause and during the follow-up. Starting from the description of the rules at the basis of intracranial pressure (Monro-Kellie's theory), definition, pathophysiology and classification of hydrocephalus will be briefly described. CT and MR imaging findings of acute hydrocephalus will be revised, highlighting the importance of a rational approach to the interpretation of CT/MR images (CSF compartments involved, entity of hypertension, etiology, etc.). Focus on specific MR imaging sequences/techniques in the assessment of hydrocephalus , before and after surgery , will be also provided (treatment efficacy, complications).

ability to compare results across centers, transfer critical medical information electronically, increase the efficiency and effectiveness of clinical treatment, improve data quality, facilitate data sharing, and help to educate new clinical investigators. Quantitative imaging biomarkers (such as volumetric assessment of traumatic brain lesions, whole brain fractional anisotropy, mean diffusivity, cortical thickness mapping, volume changes, etc.) can be correlated with TBI-specific patient scores at the level of the whole brain and of individual regions. There is a growing body of scientific evidence that quantitative (voxel-based) imaging biomarkers are correlated with clinical outcomes in traumatic brain injury, and have predictive value.

In conclusion, recent technological advances in neuroimaging have greatly improved our understanding of the pathophysiology of craniocerebral trauma and allow us to detect abnormalities, even in patients with mild head trauma, when routine imaging studies appear normal. The implementation of standardized reporting templates and the identification of quantitative imaging biomarkers will help us to improve characterization of traumatic brain injuries, and may be eventually lead to the use of neuroimaging studies as a reliable outcome predictor.

Abusive head trauma (AHT) is the most common cause of death from child abuse and the leading cause of death from traumatic brain injury in children younger than 1 year-old. More specifically, 95% of all traumatic brain injuries below the age of 1 year-old are AHT. AHT is a comprehensive term reflecting head injuries related to child abuse. In AHT, the mechanisms of injury includes shaking, impact, or a combination of these mechanisms. Since AHT is part of a disease in which children are physically abused, the diagnosis is usually made based on a multidisciplinary approach. Hallmark of AHT are retinal hemorrhages (RH). The gold standard evaluation for RH is the dilated funduscopic examination (DFE) . Recently, the capability of SWI to depict RH has been shown. SWI may be particularly useful in those patients who cannot undergo DFE. Traumatic thrombosis, traumatic rupture and leaks of the bridging veins are also frequently observed in AHT. Subdural hematomas and brain edema are a nonspecific finding in AHT. Brain edema may result from apnea/arrest, vasospasm, suffocation, or strangulation. In this setting, the role of neuroimaging is to assess the extent of brain damage. Spinal hematomas may be present in AHT. Spinal hematomas are nonspecific. However, their presence may help in distinguishing a traumatic from non-traumatic intracranial subdural hematoma. In conclusion, after this lecture the attendees should be able to identify the main neuroimaging features of AHT including RH, subdural hematomas, brain and spine injury.

There has been demonstrated that drug resistant epilepsy patients could benefit of surgical treatment. The rates of become seizure free after surgery increase if the patient has a potential epileptogenic lesion demonstrated by neuroimaging. Therefore, the MRI studies play an important role in the management of these patients. The effectiveness of the MRI studies in localize the epileptogenic lesion is related to the use of a dedicated protocol using high-resolution images and the image interpretation by a neuroradiologist expert in epilepsy.

The protocol recommended has to include a volumetric 3D highresolution sequence, coronal high resolution FLAIR or 3D FLAIR if is available, and coronal high resolution T2 FSE 2D. There are other optional sequences such IR , SWI or DIR that can provide more information in specific cases and will be discussed. It is important to know the imaging features of the most common epileptogenic lesions such temporal mesial sclerosis, cortical dysplasia and other congenital malformation and to distinguish them for normal variants. Some of the imaging findings are difficult to interpret and they would have clinical significance only if they correlate with the seizure semiology, electric pattern or other neuroimaging techniques such PET or SISCOM.

Horst Urbach (Germany)

Primary goal of MR Imaging in epilepsy patients is to detect epileptogenic lesions with small cortical malformations best detectable on a 3D FLAIR SPACE sequence with 1 mm3 voxels. Morphometric analysis of 3D T1-weighted data sets helps to find subtle lesions and may reveal the true extent of a lesion. In further presurgical work-up language lateralization and spatial relationship of epileptogenic lesions to eloquent cortex and white matter tracts must be evaluated. With clear left lateralization language fMRI is sufficient, in atypical lateralizations Wada test and electrical stimulation mapping may be added. Primary motor cortex and corticospinal tract on one and visual cortex and optic radiation on the other side are displayed with fMRI and diffusion tensor tractography. For the corticospinal tract a "global" tracking algorithm, for the optic radiation including Meyer' loop, which may be damaged in anterior temporal lobe resections, a probabilistic algorithm is best suited.

16.30-18.00 Session 4

E. Turgut Tali (Turkey)

Central nervous system infections are medical emergencies because their onset may be fulminate or insidious and delay in diagnosis and institution of appropriate therapy will result in the patient's death or in permanent, severe neurological injury. The importance of early detecting and treating brain infections is well known. It is shown that delays in diagnosis can lead to increased morbidity and mortality. Radiological evaluations play an important role in the diagnosis, subsequent treatment and also treatment monitoring of all the brain infections Meningitis is a pathological process involving diffuse inflammation of the membranes (pia-arachnoid mater and cerebrospinal fluid (CSF) or duraarachnoid mater or both) surrounding the brain and spinal cord and may be caused by any of the common infectious agents including bacteria, fungi, viruses. MRI is the imaging modality of choice for the diagnosis and the treatment monitoring. Unenhanced MR examinations of patients with early meningitis may be unremarkable. Contrast is essential and improves the sensitivity particularly in the early phase and the specificity. Postcontrast images demonstrate the abnormal meningeal enhancement. Thickening of the meninges, obliteration and contrast enhancement of subarachnoid space are differentiating findings of advanced meningitis. Imaging has also plays a major role to demonstrate and to diagnose the development of complications, including infarction, cerebritis, abscess, subdural empyema or effusion, hydrocephalus, ventriculitis, myelitis and vasculopathy. Acute encephalitides are diffuse non-focal brain parenchymal inflammatory disease. They can involve the meninges. Pathologically the primary features of viral encephalitis include neuronal degeneration and inflammation with or without mass effect. Acute encephalitides are diffuse non-focal brain parenchymal inflammatory disease. They can involve the meninges. Pathologically the primary features of viral encephalitis include neuronal degeneration and inflammation with or without mass effect. The etiology: HSV, HIV, Papovavirus, Arbovirus, Enterovirus, Toxoplasma, fungi, Listeria, Slow virus encephalitides as SSPE, Rasmussen, Prion disease as Creutzfeldt-Jacob Disease. Herpes simplex encephalitis is caused by DNA virus of 95% HSV-1. Significant morbidity is high with significant mortality. There is predilection for limbic system (temporal lobes, cingulum, subfrontal region). It is unilateral initially and turns to bilateral in the advancing stage and causes hemorrhagic, necrotizing encephalitis. MRI shows gyral edema with hypointensity on T1WI, high signal on T2WI, mass effect, patchy enhancement, petechial hemorrhages. Putamen is usually spared. Subacute Sclerosing Panencephalitis (SSPE) occurs several years after measles infection. It is common in children and young adults between 5-12 years old. Patchy demyelination and gliosis present in the WM, basal ganglia, cerebellum, pons. Imaging shows normal / hypodensehyperintense foci in the subcortical and periventricular WM, basal ganglia (well-circumscribed in basal ganglia especially into the putamen), advanced stage shows diffuse bilateral cerebral and also cerebellar, pontine involvement, generalized atrophy of the final stage. The specific cause of Rasmussen encephalitis is unknown. Pathology is suggestive of chronic viral encephalitis after CMV genome has been found. But, recent evidences suggest an autoimmune cause with cortex, basal ganglia inflammation, destruction with atrophy. Imaging: GM, basal ganglia hyperintensity, atrophy, enhancement. Decreased perfusion on PWI, decreased NAA peak, elevated glutamate/glutamine peak on MRS. MRS findings usually appear earlier than MRI.

Myelopathy simply means "something is wrong with the spinal cord". The list of spinal cord diseases is long and imaging findings are overlapping. Most common imaging finding is enlargement of the cord with T2high signal intensity in the cord. Following questions are important when analyzing spinal cord pathology: 1) How long is the lesion, 2) where is the lesion located in the cross section of the spinal cord, 3) is the lesion enhancing, 4) are syrinx or cysts present, and 4) single or multiple lesions. In some diseases signal abnormalities will extend several vertebral segments (NMO, longitudinally extensive transverse myelitis LETM, tumor, ADEM), whereas "short" lesions will be present in MS. Lateral and dorsal location suggests MS, ventral location is typical for ischemia or poliomyelitis, and dorsal location will be seen in subacute combined degeneration and HIV myelopathy. Knowledge of coexisting brain lesions is crucial for narrowing the differential diagnosis. Finally clinical information (onset of symptoms, history of travels, immune status, etc.) will be helpful to confirm or exclude specific diagnoses.

Marek Sasiadek (Poland) Conventional MRI sequences provide limited information of spinal cord pathology. Diffusion tensor imaging (DTI) of the spinal cord, including tractography, enables improved qualitative and quantitative assessment of the spinal cord lesions. DTI is based on anisotropic, one direction diffusion, which theoretically is ideally suited to imaging of spinal cord tracts.

However due to the small size of the spinal cord and presence of many artefacts, obtaining good quality DTI of the spinal cord is a challenge. Fortunately technical improvements, like parallel imaging, cardiac and respiratory gating, decrease of the FOV, reconstructive matrix and slice thickness, increased number of diffusion directions, use of 3 T MR units; caused the improved quality of DTI images. DTI of the spinal cord can be used in many pathological changes, including degenerative myelopathy, intramedullary and extramedullary tumors, spine trauma, multiple sclerosis and other inflammatory diseases of the spinal cord.

In acute and subacute setting the most promising is use of DTI in degenerative myelopathy and spine trauma. In degenerative disease of the spine DTI it is possible, on the base of fractional anisotropy (FA) and mean diffusivity (MD) or apparent diffusion coefficient (ADC) maps, to detect myelopathic changes which are not visible in plain MRI. Similarly in traumatic spinal cord injury DTI enables detecting changes in the spinal cord far from the site of trauma.

In my opinion the advantages of spinal cord DTI, described above, will result in increasing role of this technique in diagnosis, prognosis and follow-up of spinal cord diseases.

The brachial plexus is a complex anatomic structure which cannot be fully displayed with conventional 2D MR imaging. The introduction of phased array coil technology and the advent of parallel imaging with multielement RF-coils have increased the SNR of high resolution MRI while dramatically shortening imaging times, therefore enabling volumetric acquisition of MRI data. New variants of 3D FSE sequences that differ from conventional FSE sequences by long FSE readout and flip angle modulation allow rapid image formation with diminished CSF flow artifacts and high contrast resolution between spinal cord, nerve roots and subarachnoid spaces. These sequences, named with different acronyms according to manufacturer (SPACE, FSE-XETA, VISTA) represent the best solution for 3D MR Myelography, by acquiring high resolution 3D volumes and subsequently generating curved-planar or multiplanar reformats along the course of cervical nerve roots. MR Myelography based on 3D SPACE sequences is routinely used in our Department for the evaluation of traumatic injuries of the brachial plexus in which the preoperative assessment of nerve root avulsions is essential for surgical planning. The whole spectra of imaging findings, including traumatic pseudo-meningoceles and partial or complete nerve root avulsions can be easily identified with carefully selected submillimetric multiplanar reformats.

In conventional MRI studies peripheral nerves are poorly visualized due to low contrast resolution between nerves, muscles and vessels, signal intensity variability, pulsatility artifacts and small size of the nerves. MR Neurography, a tissue-selective imaging, based on T2-weighted sequences with fat suppression, directed at identifying and evaluating characteristics of nerve morphology, has been widely used for the evaluation of traumatic injuries, nerve entrapment syndromes and nerve tumors. The development of high resolution 3D MR neurography techniques has significantly improved the radiological approach to the investigation of brachial plexus, due to enhanced contrast between nerves and muscles and multiplanar capabilities, which allow coronal MIP views with simultaneous display of the roots, primary trunks, divisions and cords of the brachial plexus. 3D MR neurography is especially useful for the investigation of immunemediated brachial plexopathies, which are characterized by different patterns of enlargement and increased signal intensity, whose identification may be relevant for the diagnosis. DTI is a novel technique which has been recently applied to the evaluation of peripheral nerve disorders. This technique is sensitive to subtle changes in tissue at the microstructural level and allows quantitative measurement of nerve microstructural integrity. DTI tractography has been successfully applied to the median nerve at the carpal tunnel and sciatic nerves, however it cannot be as readily and reliably performed in the investigation of brachial plexus for technical and anatomical reasons such as susceptibility and pulsation artefacts as well as motion of organs in the thorax. A standardized method for DTI tractography at 1.5T has been developed in our institution for the investigation of traumatic injuries of the brachial plexus, in which a reliable diagnosis of nerve root avulsion can be obtained with a functional rather than a conventional anatomic approach. 

Microsurgical resection is the first-line therapy or "gold standard" for many brain arteriovenous malformations because of its high cure rate, low complication rate, and immediacy. Surgical results have improved over time with: (1) the creation of grading systems to select patients likely to experience optimal outcomes; (2) the development of instruments like bipolar forceps and AVM microclips that coagulate or occlude feeding arteries effectively; (3) the recognition of AVM subtypes that help decipher AVM anatomy; and (4) the refinement of surgical approaches, strategies, and dissection techniques that facilitate safe AVM resection. A consecutive, single-surgeon experience with 675 patients is reviewed to demonstrate that these advances. This presentation will discuss: patient selection using the Lawton-Young supplementary grading system; microsurgical strategy using a system of AVM types and subtypes; surgical technique using a standardized eight-step plan; and multimodality approaches using volume-staged radiosurgery to downgrade large AVMs and convert them to operable lesions.

Consideration of the primordial phylogenetic compartmentalization, of the ontogenetically apparent neuromeric composition and of the recent results on the histogenetic and genoarchitectonic subdivision of the brain in the MR-and angiographic analysis of brain AVM's shows that brain AVM's have a characteristic topology which respects the underlying architectonic organization of the brain. In addition, this correlation shows that the shape and orientation of the AVM-nidus conforms to the shape and orientation of the individual histogenetic unit involved by the AVM. Each of these units has its own vascular organization characterized by a principal and accessory arterial supply and venous drainage which provides the arterial supply and venous drainage of the AVM. Large AVM's expand the affected histogenetic unit but do not extend in adjacent units which become compressed and displaced. This indicates that histogenetic units have molecularly defined boundaries which are respected by enlarging AVM's. For the endovascular treatment of brain AVM's to be effective and safe, identification of the involved histogenetic unit, knowledge of its vascularization and targeting superselectively the nidus in order to achieve a strict intranidal deposition of a liquid, polymerizing embolic material is essential. This concept proved useful in achieving a complete obliteration rate of nearly 40% with a morbidity of 2% and a mortality of 1.5% in a consecutive series of 1114 patients with brain AVM treated by endovascular techniques.

Understanding symptoms of unruptured brain AVMs is intimately related to neuroimaging, evaluation of the angioarchitecture of the AVM and proposition of specified pathological mechanisms. The most commonly encountered pathomechanisms in unruptured, symptomatic brain AVMs are: high flow angiopathy and venous congestion. High Flow is related to direct fistulous pial arteriovenous malformation or fistulous compartments in complex AVMs. When present in childhood, high flow can lead to psychomotor developmental retardation or cardiac insufficiency. In adult life, high flow has been related to perinidal hypoxemia and, thus, arterial steal which may manifest itself with epilepsy, migraines, focal neurological symptoms or brain atrophy. Imaging findings in high flow angiopathy will include: significant arterial enlargement, flow related aneurysms, venous ectasias and pouches and secondary induced changes such as perilesional angiogenesis including leptomeningeal collaterals and transdural supply and development of venous outflow stenosis. Perfusion imaging may demonstrate perilesional hypoperfusion with decreased cerebral blood flow and volume. Venous congestion can be due to a high input or a reduced outflow (secondary stenosis of the draining veins) and may go clinically along with cognitive decline, epilepsy, and neurological deficits. Patients with venous congestion may demonstrate a pseudophlebitic pattern with increased number and caliber of corkscrew-like draining veins remote from the AVM, venous obstruction and rerouting, delayed venous return and perfusion anomalies with increased blood volume and increased mean transit time (MTT) indicating venous hypertension.

10.45-13.00 Session 2

Cerebral arteriovenous malformations are rare and complex vascular lesions . Their natural history is only partially understood and it is a subject of debate. Whilst invasive treatment of an asymptomatic AVM has been challenged by the ARUBA trial , the natural history of an AVM that has bled is characterized by significant morbidity-mortality due to an increased haemorrhagic risk. Microsurgey, radiosurgery and endovascular embolisation are the principal therapeutic modalities applied individually or in combination according to different selection criteria . The role of endovascular embolization has recently changed playing a complementary role in support of radiosurgery or neurosurgery rather than representing the sole treatment technique. This talk will focus on the precise angiographic analysis of the vascular arterial composition and intrisinc angioarchitecture of the nidus of the AVM by superselective microcatheterization. This is a foundamental prerequisite to identify the types of the feeding arteries and pattern of their supply, the number and vascular connections of nidal compartments and the morphology of the vascular spaces. Recognition of secondarily induced high flow phenomena such as neoangiogensesis is also essential for a comprehensive evaluation and assessment of the associated haemorrahgic risk of AVM and for endovascular treatment planning.

Veins appear to be vital both in the development of AVMs and in their growth. Venous organization will affect the disease's natural history and play a role in therapeutic risks. However, the venous aspects of AVMs are often insufficiently assessed, with attention only given to the presence or absence of stenoses or dilations of the main draining vein, and the presence or absence of veins connecting to the deep venous system For sulcal AVMs, there may be only a single vein initially, then anastomoses at the brain surface and multidirectional drainage. For gyral AVMs drainage must use several veins and directions. A single drainage direction would indicate secondary thrombosis and suggest a higher risk factor. A superficial AVM will drain into superficial veins. Anastomoses exist between cortical and subcortical veins but are rarely used and subependymal drainage disappear once the superficial AVM has been treated. However, if the superficial AVM has a deep element, drainage will be mixed. In this case, each of the venous systems will evolve to suit its own needs, but because of the intranidal communications, any untimely occlusions of draining veins in one compartment will overload the other, increasing the risk of rupture. This event makes up a good part of the complications.

Deep venous drainage is significantly associated with a hemorrhagic presentation. It is also associated with the risk of rebleeding. The evolution of deep venous drainage will condition the evolution of symptoms and explain a number of late complications in endovascular interventions.

Perinidal Dilated Capillary Network (PDCN), also known as Reserve Nidus or Modja-modja vessels (shaggy hair) refers to abnormal dilated and fragile vascular groups, resulted from a hemodynamic overload state. They are localized proximal to the nidus and may subsequently become part of the nidus. These perinidal capillaries connect to the nidus, feeding arteries, and draining veins via arterioles and venules; they also connect to normal capillaries, arterioles, and venules. It is possible that this capillary network, not only could mimic tiny brain AVMs, but also could contribute to postoperative bleeding, and to nidal recurrence after excision. Histopathologic, PDCN is characterized by arterioles, venules, and capillaries of dilated at different sizes, with calibers ranging form 10 to 25 times that of normal capillaries, densely present around the nidus. The initiating mechanisms to recruit these neighbor vessels are related to its lowered perfusion and to increased venous pressure, consequent to the diversion of arterial flow away from the surrounding tissue towards the AVM and to the lower resistance in the shunt. As a result, this surrounding tissue marginally perfused, simulating ischemic and/or hypoxic conditions, secretes substances such as adenosine, endothelial growth factor, hypoxia-inducible factor 1, and angiopoietin-tie2, which induce blood vessel formation and growth.

In conclusion, PDCN may contribute to postoperative bleeding and nidal recurrence after complete embolization of the nidus. Therefore, it's of highest importance, by a slow and controlled injection, to occlude these abnormal vessels aiming to achieve a better and safer result.

The therapy of cerebral AVMs has rapidly evolved in the last 10-15 years, with the establishment of radiosurgery as a primary treatment and with significant advances in embolization. Shifting from surgery to alternative therapeutical options has possibly allowed better results in complex cases, but also increased the percent of partially treated patients. For these reasons the Columbia University has conducted an international study (the ARUBA), aiming to evaluate the risks of active versus conservative treatment in patients with unruptured AVMs, through the application of a combined endpoint (death or "symptomatic stroke"), reached in 10.1% of patients managed conservatively versus 30.7% of patients submitted to (any kind of) treatment. Combining death with "symptomatic stroke" is debatable, because the term "symptomatic stroke" was applied also to mild or minimal symptoms. Since embolization is frequently associated with transient deficits and was the most frequent procedure in the active group, this has influenced the final results, with 14 patients having focal deficits -although reversible in 10versus one patient in the conservative group. Moreover, the risk of hemorrhage in the conservative group was negligible due to the short follow-up (average 33.3 months), although the risk of hemorrhage was calculated at 2.2 % per year. In summary, the ARUBA has confirmed that an incomplete treatment is linked with a worse outcome. As a consequence, a precise therapeutical strategy should be defined in the individual patient before starting treatment and should be pursued until complete exclusion of the AVM; this strategy must be discussed with the patient and the therapeutical risks explained, not omitting the undeniable risks of a conservative attitude (even for unruptured AVMs).

14.00-16.00 Session 3

The trans-venous approach in the endovascular treatment of brain AVMs is based on the consideration that the cure of the AVM is obtained after the intranidal segment of the draining vein is completely occluded. Although the complete occlusion of the malformative nidus might be achieved through both the trans-arterial and trans-venous approach, the principle is completely different: the conventional trans-arterial embolization follows the centripetal pathway, with the passage of embolizing agent from the nidus towards the vein, that is reached only in the final phase of the treatment. Contrarily, the venous approach follows the centrifugal pathway, with the immediate occlusion of the intranidal segment of the draining vein and the retrograde occlusion of the nidus and arterial feeders.

In the trans venous approach the intranidal origin of the vein became the fulcrum of the whole intervention balancing the retrograde intranidal embolic material penetration with the emissary vein retrograde diffusion . However, it is mandatory to perform a super-selective microcatheterization of the main arterial feeder in order to have a clear identification of the nidal angioarchitecture and of the intranidal segment of the draining vein without the overlap with other vascular structures. The indications for the venous approach are still limited: single drainage (preferably deep), small AVMs or surgical remnants, AVMs that are not treatable either with other approaches or surgically.

Howard A. Riina (USA) Current management standards for intracranial AVMs will be reviewed in an interactive format with course participants. This will include the roles of angiography and embolization (as both stand alone and pre-operative therapies), surgical resection and radiosurgery in the treatment of these lesions. Strategic decision making depending on lesion size, location, and angio-architecture will be explored. In addition, the affect of the recent ARUBA trial results and its effect on clinical decision making will also be reviewed.

Lastly, an open discussion about controversies including partial embolization, staged radiosurgery and trans-venous embolization will be considered.

Michael Söderman (Sweden)

Brain AVM was one of the first pathologies treated with stereotactic radiosurgery, notably the Gammaknife. Almost all treatment and outcome models are thus derived from the abundance of data from Gammaknife treatment. Due to differences in radiation dose distribution these models may not be fully applicable to treatment with linear accelerator or proton beam generator.

The results from SRS of brain AVM are predictable and depend on a few well defined parameters:

•The chance for obliteration depends on the radiation dose to the periphery of the AVM nidus. Typically a radiation dose of 25Gy will incure an 80% chance for obliteration over a three year period.

•The risk for adverse radiation effects (oedema, radionecrosis, cysts) depends on the amount of energy deposited into the target and the surrounding brain. Thus the higher the radiation dose and the bigger the target the higher the risk.

•The risk for hemorrhage during the latency period before occlusion (maximum of three years) depends on the radiation dose to the periphery of the nidus, the nidus volume, previous recent hemorrhage and probably AVM location. Thus the higher the radiation dose and the smaller the target -the lower the risk for hemorrhage. Previous recent hemorrhage and central AVM location increases the risk.

16.30-18.00 Session 4

Clinical observations and improved MR imaging quality helped to unravel stepwise the pathophysiology and spontaneous evolution of spinal dural AV-fistulas (SDAF). Similar to their cerebral counterparts, SDAVF likely have to be seen as a consequence of localized thrombosis of venous structures close to the dural sack, such as epidural veins or radicular veins, followed by secondary ingrowth of neovascular meningeal vessels in view of clot resorption and organization attempts. In case there is a radicular venous connection to such a DAVF area, reflux towards the medullary venous system may develop and present as SDAVF. Biomechanical transduction of pulsatile arterialized flow in the medullary venous system encountering the pulsatile CSF environment are leading to thickening of the venous wall and increased narrowing of the normal radicular veins at the level of their exit towards the epidural venous system. Secondary to the development of a SDAVF, these processes may entail stepwise occlusion of normal radicular draining veins and in general lead to development of ascending venous hypertension of the spinal cord. Spinal cord T2 hypersignal corresponds initially to a disturbed reabsorption of CSF, facilitating chronic ischemic damage to the spinal cord and in case of further hindrance of the venous drainage and persisting SDAVF, may even induce venous infarction. Current MR quality may allow for discovering incidentally increased perimedullary vascularity and further evaluation with MRA or DSA may confirm presence of a SDAVF. At early stages, no venous congestion may yet exist, nevertheless, one can advocate to treat SDAVF already at this stage to avoid further damage to the medullary venous system.

Hans Henkes (Germany)

Paraspinal arteriovenous fistulas are infrequently encountered lesions. They can be either congenital or acquired. Indications for treatment include (but are not limited to) bruit, pain and spinal drainage. The mode of endovascular treatment of these lesions depends on the clinical signs and symptoms, and is highly individualized. Makrofistulas between the vertebral artery and the jugular vein can be occluded with coils or the continuity of the artery can be reconstructed with either telescoping stents of with flow diverters. Paraspinal lesions with an angioarchitecture similar to an AVM can be occluded with injected polymer glue. Spinal dural arteriovenous fistulas are acquired lesions, located adjacent to the neuroforamen. The arteriovenous shunt to the epidural veins interferes with the perfusion of the myelon, resulting in edema of the myelon and progressive myelopathie. EVT is considered if the segmental artery from which the radiculomeningeal artery to the AV shunt originates, is independent from the pial supply of the myelon. For spinal dAVF with a common segmental origin of the feeding artery to the fistula and the myelon supply, microsurgery is mandatory. The clinical recovery is better in patients who have been treated early in the course of their disease. The interruption of the AV shunt has to be verified angiographically after endovascular and after microsurgical treatment.

There are two groups of intradural spinal arteriovenous malformations (AVMs): peri-medullary fistulas (PMF) and pial and/or intra-medullary AVMs.

Both groups of malformations are fed by anterior and/or posterior radiculo-medullary arteries. PMFs are divided in three groups depending on their size ( J.J. Merland ) :

Type 1 or small size or Type 2 or medium size and Type 3 or giant size. PMFs Type 1 and 2 are more frequent in young adults ( 25 -40 years ), they drain far away from the point of fistula and they present clinically through retrograde venous hypertension ( like the dural spinal fistulas) and/or hemorrhage ( unlike dural spinal fistulas which almost never bleed ). Giant PMFs or Type 3 are more frequent in children, they have locoregional venous drainage with giant venous ectasia. They manifest clinically with hemorrhage, mass effect and haemodynamic steal syndrome. The most common locations of the PMFs are: conus medullaris in Type 1, thoraco-lumbar spinal cord in Type 2 and cervico-thoracic spinal cord in Type 3. The pial and/or intra-medullary AVMs are more frequent in teenagers and in young adults, they are usually multipediculated with a locoregional venous drainage. They frequently present with subarachnoid hemorrhage or hematomyelia. AVMs located in the thoracic spinal cord have the worst prognosis.

Embolization is the most recommended treatment in Type 2 and 3 PMFs as long as there is a possible superselective access to the malformation.

In our opinion, surgery should be indicated in Type 1 and 2 PMFs with posterior location and in the pial malformations with posterior or lateral location. Recent discoveries about the genomic characteristics of brain tumors have revolutionized our understanding of tumorigenesis and tumor biology. Histopathology-based diagnostic categories, such as medulloblastoma, which due to histoarchitectural phenotypic similarities, have been historically considered to represent a distinct disease, are now recognized to encompass "transcriptionally" and clinically distinct diseases. Epigenetic factors (e.g. histone mutations in pediatric high-grade gliomas) add another layer of complexity but all of these new insights explain previously poorly understood biological and imaging phenotypic features and variations, such as location, prognosis and pave the way to new management options. The underlying mutations and pathway abnormalities are increasingly elucidated and these developments should have an impact on the neuroradiologist's approach to the evaluation of these disease. "Imaging genomics" is a rapidly developing concept which needs to be adopted by the neuroimaging community. Proceedings of ongoing and future molecular biology research are expected to rewrite the "book of brain tumors" as we know it.

Tarek Yousry (UK)

Imaging, especially MRI plays an important role in the management of intracerebral tumours, such as gliomas. In the last 1-2 decades a number of important technical developments led to significant improvements in "anatomic" imaging, and had an even bigger impact on the large range of "physiologic" imaging techniques available today. These advanced MR techniques have been providing significant contributions to the furthering of our understanding of the biological processes that influence the evolution of gliomas and thereby determine the final clinical outcome. There is however a wide variety of opinions on the role and relevance of these techniques in the management of the individual patient in every day's clinical practice. This role is determined by the clinical question to be answered, which can be reduced to 4 general scenarios: 1. establishing the diagnosis of a tumour (tumour vs abscess/infract, etc.); 2. differential diagnosis (which kind of tumour, glioma, grade?); 3. preoperative planning; and 4. assessment of treatment response. The potential role of the individual techniques is determined by their capacity to change the management of the individual patient in each of these scenarios.

In this presentation, we will focus on the first 3 scenarios, presenting different viewpoints and suggesting an efficient MR protocol that is based on the currently available scientific evidence.

Primary brain tumours are histopathologically subtyped into World Health Organisation (WHO) grades I to IV, according to -increasingdegrees of malignancy. These grades provide prognostic information and guidance on management, such as radiotherapy and chemotherapy after surgery. Despite the confirmed value of the WHO grading system, a multitude of studies and prospective interventional trials indicate that tumours with identical morphological criteria, i.e. of the same WHO grade, can have highly different outcomes.

To personalise brain tumour management, we need additional diagnostic markers that can differentiate tumours beyond the current morphological WHO grading system. Molecular markers can distinguish subtypes of tumours within the same morphological type and WHO grade, and are therefore of great interest for personalised medicine. Recent genomic wide studies have resulted in a far more comprehensive understanding of the genomic alterations in gliomas, and the suggestions of a new molecularly based classification. MR imaging phenotypes can serve as non-invasive surrogates for tumour genotypes and as such provide important information on diagnosis, prognosis, and, eventually, personalised treatment. The newly emerged field of RadioGenomics links specific MR imaging phenotypes with gene expression profiles. In this presentation I will discuss the three best known tumoural genotypes with prognostic andpotentialtherapeutic consequences: 1. isocitrate dehydrogenase (IDH) mutation, 2. 1p19q deletion, and 3. methyl guanine methyltransferase (MGMT) promotor methylation. I will give an overview of the known and potential MR imaging features of these genotypes, and their value and validity in a clinical context.

In glial tumors,methylation of MGMT promoter is associated with a better response to treatment with Temozolomide.Gene mutations for IDH is associated to a better prognosis too,owing to a reduced methabolism with reduced tumoral growth,characteristics associated to a less aggressive tumoral behaviour.Both these features are associated with an increase of mean survival. In our experience with the use of conventional and advanced MR imaging and specially DWI and DTI we have tried to predict the molecular profile of glial tumors and in particular the presence or the absence of mMGMT and IDH mutations.Summarizing : -high min. ADC ratio (tumour/normal tissue) is associated with mMGMT -high radial and mean diffusivity are associated with IDH mutations.

Radio and chemo-therapies are the standard types of treatment methods in postoperative patients with operated and metastatic brain tumors.

Therefore, radiation therapy and chemotherapy induced changes are important components of imaging brain tumors. Typically, patients begin radiation treatment within 2 to 4 weeks following tumor resection. In many cases, distinguishing recurrent tumors from radiation necrosis on follow-up can be challenging. Therefore, understanding underlying pathophysiological mechanism and differential diagnosis of recurrent tumor versus radiation changes, specially radiation necrosis and post chemotherapy changes becomes important in management of these tumors. Due to low sensitivity of conventional MRI, functional imaging methods are advised to be used routinely, especially in irradiated postoperative brain tumors. Hence, principles of functional imaging findings, should be understood clearly. In this lecture underlying pathophysiology that creates imaging findings in irradiated brain will be explain. Based on this knowledge, principles, applications, and pitfalls of various radiological imaging techniques will be discussed. Findings of imaging methods will be further explained to understand post therapy and chemotherapy changes.

Most of the published studies that have investigated the usefulness multimodality imaging suggests that the conjunction of morphologic imaging with functional imaging lead to a significant improvement in the diagnosis and follow up of several types of diseases. The conjunction of Positron emission tomography with Computed tomography (PET/CT) in example brought a new perspective into the fields of clinical and preclinical imaging. This conjunction allow the combination of anatomical information, revealed from CT, and the functional informations from PET into one image with high fusion accuracy. Hybrid imaging by means of PET/CT has shown its potential in the evaluation of solid tumors as lung or colorectal cancer but did not lead to significant advantages in both neurological and neuro-oncological applications, where the use of CT (also with contrast media) covers a minor role. During the last years, several novel radiolabeled compounds have been developed and are actually used for in vivo evaluation of primary and secondary brain tumors (i.e. 18F FDOPA) or neurodegenerative diseases (i.e. 18F Florbetaben). The common denominator of these radiolabelled compounds is an high selectivity and specificity for the target, with a loss of background informations that could be used by nuclear medicine physicians as a surrogate of anatomical reference. Magnetic resonance imaging (MRI) provides unmatched soft tissue details for brain studies and cover a major role in the diagnosis and follow-up of both neurodegenerative diseases and primary and secondary tumors of the brain. Additionally, since MRI provides also functional information such as blood oxygenation level dependant imaging or spectroscopy, the conjunction of PET with MRI (PET/MRI) could provide multi-functional information of physiological processes in vivo along with a reasonable array of functional informations through techniques such diffusion. First experiments with PET/MRI prototypes showed very promising results, indicating its great potential for clinical and preclinical imaging.

Imaging is the basis of an efficient radiotherapy, used either in the planning and in the treatment for: -Visualization of the tumor -Proper identification of the target volume (target) -Evaluation of the organs at risk (OAR) -Verification of the set-up Technological developments achieved in both fields of radiotherapy and diagnostic imaging have led to an increasing precision in the treatment of tumors. Developments of diagnostic imaging provides images more and more detailed than in the past. This allows the possibility of issuing higher doses to target volumes, increasing the preservation of healthy tissues and minimizing the dose to the critical organs. Molecular imaging influence the management of cancer patient, and assist the customizing of treatment. The positron emission tomography allows the visualization of molecular alterations in vivo, then it facilitates early diagnosis and treatment of the disease. The definition of target volumes is based mainly on diagnostic imaging. CT Scan is the tool of choice (anatomical description of volumes and allows the dosimetric calculation). MR gives an excellent soft tissue contrast. PET allows the physiological information and displays the proliferative activity, the differentiation of necrotic regions from recurrence (important the timing in which is checked), the identification of hypoxic regions If target delineation is inaccurate, highly conformal radiation techniques such as IMRT is ineffective. Coregistration of CT with MRI provides important complementary information and overcomes some shortcomings of each individual modality (these structural imaging techniques have inherent limitations in their capacity to differentiate tumor from neighboring normal tissues). Much of the published literature has demonstrated that utilization of PET results in differences in the magnitude of the target volumes (mostly smaller volumes) and a reduction in interobserver variation. A better OARs definition is provided by MRI. One of the most controversial and as yet unresolved issues in applying PET/CT in radiation planning is the method used for edge definition. CT, MR, PET adds complementary information and their combined use is recommended. However physical examination must be incorporate as an essential step in precise GTV delineation. Additional histopathologic correlation studies as well as large multicenter prospective trials analyzing clinical outcomes are needed.

Purpose: Long-term epilepsy associated tumors (LEAT) represent a frequent cause of focal epilepsies expecially in children and in young adults. LEAT includes neoplastic lesions identified in patients investigated for long histories (often 2 years or more) of drug-resistant epilepsy. They are generally slowly growing, low grade, cortically based tumors commonly arising in the temporal lobe. Focal cortical dysplasia (FCD) or other neuronal migration abnormalities often coexist Methods: The authors retrospectively reviewed MRI study of 52 patients (age at surgery range 3-63 years) affected by pharmacoresistant temporal lobe epilepsy who underwent surgery in the period 2002 to 2014 for histopathologically confirmed LEAT (follow-up ranged from 1 to 13 years). The patients were also divided into 2 groups patients in Group A (6 cases) underwent to lesionectomy for extratemporal lesion, whereas patients in Group B (46 cases) underwent removal of the tumor and the adjacent epileptogenic zone (tailored surgery). Result: Gangliogliomas were predominant lesions found in 23 pts followed by pleomorphic xanthoastrocytoma (8 pts), gangliocytoma (4 pts), asto-oligoastrocytoma (8 pts), dysembryoplastic neuroepithelial tumors (4 pts), melanocytoma (1 pt), neurocytoma (1 pt), papillary glioneuronal tumor (1pt), anglocentric glioma (2 pt), In 17 cases LEAT were associated with FCD. In this group, FCD was in 9 cases (53%) a FCD IIIb according to the last International League Against Epilepsy (ILAE) classification (FCD I+EAT), whereas in 8 cases (47%) LEAT were associated with FCD type II (atypical association) In 1 case we observed an anaplastic progression. Conclusion: The correct MRI identification of the structural lesion (tumor and focal cortical dysplasia ) associated with an extensive neurophysiological study, are essential to draw a tailored surgical approach in order to obtain the best post-surgery seizure control. The main issue for neuroradiologists is trying to identify an associated FCD since its presence could change presurgical work up demanding a more extensive non invasive neurophysiological study (i.e video-EEG monitoring) to define the epileptogenic zone and to choose the best surgical strategy (lesionectomy vs "tailored" 

Purpose: Adrenomyeloneuropathy (AMN) is the late-onset form of adrenoleukodystrophy (ALD), a X-linked disease due to defect of the peroxisomal ABCD1 transporter, leading to very long chain fatty acid (VLCFA) accumulation. This in turn leads to oxidative stress and progressive axonal damage, consisting in a dying-back axonal degeneration of the long tracts of the spinal cord, with brain MRI usually normal. In this work we used Diffusion Tensor Imaging (DTI) to assess and quantify possible brain microstructural changes in AMN. Purpose: Adrenomyeloneuropathy (AMN) is the late-onset form of adrenoleukodystrophy (ALD), a X-linked disease with a progressive axonal damage, consisting in a dying-back axonal degeneration of the long tracts of the spinal cord. In this work we present the application of advanced quantitative Magnetic Resonance Imaging (qMRI) methods to assess spinal cord structural and microscopic changes in AMN. Methods: Spine qMRI data of 13 AMN male patients and 12 ageand gender-matched controls were acquired at 3T (Achieva, Philips). The protocol included sagittal 3D-T1 Fast Field-Echo (FFE) and axial Diffusion Tensor Imaging (DTI) acquisitions (b=600 s/mm², 6 directions). Total cross-sectional area (TCA) was measured at all the intervertebral cervical disk levels and the upper thoracic levels down to T2-3, after reslicing the 3D-T1 FFE images orthogonally to the spinal cord using the software JIM6 (Xinapse Systems). Interoperator reliability was assessed. Fractional anisotropy (FA), mean, axial and radial diffusivity (MD, AD and RD) maps were computed at C2-3, C3-4 and C4-5 levels using the FMRIB Diffusion Toolbox (FSL). FA, MD, RD an AD values were evaluated both in gray (GM) and white matter (WM) using ROIs extracted by the MNI-poly-AMU template. Result: TCA was significantly reduced in patients at all explored levels (independent samples T-test after testing for normality, p<.0001); the relative reduction was more pronounced at the thoracic levels. There was an excellent interobserver reproducibility of TCA measurements (mean ICC: .995, p<.001). A significant reduction of WM FA (p<.0001) with a concomitant reduction of AD (p<.003) and increase of RD (p<.003) was observed at all the explored levels. A trend to a reduction of FA in the GM of the spinal cord was also observed at the lower cervical level explored (C3-4 and C4-5 There is relative paucity of large studies in the pediatric population compared to studies in adults.

We identified the imaging findings in PRES in the pediatric population and compared the results with findings described in adults.

Methods: 34 cases were reviewed from 32 patients (2 patients had a second episode at a different time point). We documented the etiology, clinical course and imaging findings including the distribution of the lesions in the brain, presence of hemorrahge, increased or decreased diffusion, contrast enhancement, and frequency of resolution of findings on follow up studies.

Result: The patients included in the study were the 68% female and ranged between 4-23 years of age (mean age 11 years). More than one lobe was afected in 94% of our patients, with imaging abnormalities in frontal lobes in 91%, in parietal lobes in 85%, in temporal lobes in 42% and in occipital lobes in 91% of cases. Cerebellar signal abnormalities were seen in 36% of cases. A majority of our cases showed increased signal intensity in DWI but only 15% of our cases had focal restriction diffusion, reflecting vasogenic edema more often than citotoxic edema. Hemorrhage was identified in 12% of cases, mostly seen as multiple punctate foci. Amongst the patients who were administered intravenous contrast medium, 50% had lesions that showed enhancement. Enhancement was predominantly leptomeningeal (100%) and 25% demonstrated both leptomeningeal and parenchymal enhancement.

Of the 56% patients who had a follow up MRI, only 53% of cases had complete resolution of MRI findings. Conclusion: Pediatric PRES has some distinctive imaging findings compared to adult PRES. We found a higher incidence of frontal and cerebellar involvement and more frequet presence of hemorrhage. Residual abnormalities were seen at a higher rate compared to adults.These aspects may reflect differences in the vulnerable vascular areas in infants. We propose a change in nomenclature of PRES to Potentially Reversible Encephalopathy Syndrome to reflect the findings of this study. The endovascular treatment of intracranial aneurysms has been steadily evolving over the last 25 years to a point where it has become a viable and safe alternative to surgical clipping. The introduction of the Guglielmi Detachable Coil (GDC) system in the early nineties was a significant step towards improving the predictability of the detachable system and thus the safety of occluding an aneurysm with an implantable device. Subsequently, several enhancements of the coil itself were introduced in a major effort to reduce the recanalization rates, especially in large or wide neck aneurysms. These enhancements consisted primarily of adding a suture material to the platinum or coating it with a hydrogel polymer in an effort to reduce the dead space, increase the production of smooth muscle cells and thus reduce the recanalization of soft thrombus. Unfortunately, several randomized studies failed to demonstrate any clear advantage of the surface-modified coils over bare platinum coils in reducing the recurrence rate especially in large and wide neck aneurysms.

In the late nineties, and with the introduction of the liquid polymer Onyx, several attempts were made to replace or complement the platinum coils with the non-adhesive polymer as an adjunct for obliteration of the aneurysm. Various methods were used to retain the liquid polymer within the aneurysm including balloonassisted and stent-assisted techniques. Despite good anatomical results, these techniques have largely been abandoned due to difficulty in using them as well as the relatively high rate of inadvertent distal embolization, and stenosis/obliteration of the parent artery.

Meanwhile, early seminal studies had shown that the deployment of bare stents within the parent artery can lead to the progressive thrombosis and obliteration of experimental aneurysms without the need to implant an embolic material, coil or otherwise, inside the lumen of the aneurysm. Also, experience had shown that the deployment of bare metallic stents in the intracranial circulation was much easier than the navigation of covered stents which are usually large in diameter and too stiff to navigate. In addition, a group of investigators explored the hemodynamic effect of flow diversion on the intentional obliteration of in-vitro and experimental animal aneurysms. The investigators were able to scientifically and mathematically prove the beneficial effect of implanting a "Flow Diverter" stent in the parent artery across the neck of an aneurysm on the obliteration of that aneurysm. Thus the concept of flow diversion for the endovascular treatment of aneurysms was introduced. The flow diversion concept stipulates that the mere presence of a tightly woven stent-like device a cross the neck of an aneurysm will alter the flow in such a manner that it will lead to decoupling of the intraaneurysmal flow patterns from those inside the parent artery. Such a decoupling will lead to slowing and alteration of the intra-aneurysmal flow pattern ultimately leading to thrombosis. These changes induced by the flow diverter will happen with or without the presence of coils inside the lumen of the aneurysm.

Early clinical studies have shown positive results using the flow diversion techniques in the treatment of aneurysms both in the carotid as well as in the vertebro-basilar circulations. The technology has taken off dramatically first in Latin America and Europe and more recently in North America and Asia. Several improvements in the design and manufacturing of the devices have ensued leading to ever greater and increasing use. Despite the continuing success of the technology, several drawbacks and unexplained complications have become known and will need to be solved if not better understood. These include: the need to use dual antiplatelet therapy with all the inherent problems of this combination of drugs, unexplained aneurysmal rupture some of it fatal, unexplained remote cerebral parenchymal hemorrhages, etc. Although flow diversion techniques are rapidly being adopted for the treatment of side-wall aneurysms, the technology remains unsuited for the treatment of bifurcation aneurysms such as basilar tip, internal carotid bifurcation, etc. For this category of challenging aneurysms a new family of devices have been developed which consists of spherical or cylindrical shape implants made of braided metallic material (Web device, Luna device). These new implantable devices belong to the category of intra-aneurysmal flow diverters and are distinctly better suited for the treatment of bifurcation aneurysms. They have shown promising early clinical results, particularly in the treatment of acutely ruptured aneurysms where the use of dual antiplatelet therapy can be problematic. Since these implants do not extend into the parent artery, pre-treatment with antiplatelet therapy is theoretically not required. Other newer devices (Barrel stent, P Conus, etc.) are being introduced for the treatment of wide neck bifurcation aneurysms with the main purpose of avoiding the cumbersome and often challenging use of "Y Stenting". The construction of these devices is designed such to buttress the coils inside the aneurysm and to protect the parent artery and its various branches from inadvertent encroachment by the platinum coils. Current management standards for intracranial aneurysms will be reviewed in an interactive format with course participants. This will include the roles of angiography and embolization, surgical clip reconstruction and the role of following lesions conservatively. The continued coiling vs clipping debate will be explored as well as how this debate has now shifted to include flow diversion and the treatment of small aneurysms. Strategic decision making depending on aneurysm size, location, and morphology and how these factors influence the use of detachable coils, newer generation devices and flow diverters will be discussed. Lastly, an open discussion about controversies in aneurysm management including the continued use of coiling as a stand alone therapy, placement of coils in conjunction with flow diverters and the question of surgical clipping as a first line treatment in some geographical locations will be considered.

Lucio Castellan (Italy)

The management of intracranial aneurysms has evolved significantly over the past 2 decades. The endovascular treatment of anterior circulation aneurysms has become a common therapeutic option in our neuroradiological departments, still sometimes representing a challenging problem for physicians and patients. From the clinical experiences in the last 20 years we know that not all aneurysms are suitable for coil embolization. Suitability depends on the size, anatomy, and location of the aneurysm. Large aneurysms or wide neck aneurysms are less likely to achieve total occlusion. They are also more prone to aneurysm recurrences and to complications such as coil compaction or parent vessel occlusion. Furthermore, aneurysms in the middle cerebral artery bifurcation are less suitable for coil embolization. However experience and technological advances have broadened the indications for endovascular treatment of all aneurysms of the anteriori circulation. Balloon-assisted coiling and stent-assisted coiling have been the main technological advancements that have made the treatment of previously uncoilable aneurysms feasible. Moreover today flow divertion devices can be considered in a new therapeutic strategy in some ruptured aneurysms of the anterior circulation. As with all intracranial aneurysms, complete angiographic occlusion remains the goal of care. Balancing the risks of thromboembolic complications with decreasing the risk of hemorrhage, especially in acutely ruptured aneurysms, represents an objective for interventional neuroradiologists.

Defining complex aneurysm has very different parameters in the point of neurosurgical and endovascular view..A so called easy surgical aneurysm case, if there is any easy craniotomy from the patients perspective, can be a very challenging case for endovascular approach and a very easy endovascular case can be a very though surgical case. Complexity of an aneurysm case could be also coming not only from morphologic settings but also from clinical presentation of that particular aneurysm case. Herein this lecture, these differences will be emphasized under the light of recent endovascular technical advances and the definition of the complex aneurysm case in 2015 will be made.

Endovascular treatment of cerebral aneurysms may be challenging according to some specific features of the aneurysms: broad base, direction of the sac and arteries originating from the sac. According to these conditions, the endovascular treatment may be performed with simple coiling only in sporadic cases. In most of the cases the coiling should be assisted by balloon (overall in ruptured aneurysms) or stent (overall in unruptured aneurysms). In wide-necked aneurysms, a single stent may be insufficient to contain the coils within the sac, therefore, two stents in a Y-shape configuration or in parallel may be used. Some other devices to contain the coils have been introduced and these represent the evolution of the Y-stenting or Wafflecone technique, such as the PulseRider or the PConus, that are stent-like devices with intra-or extra-saccular deployment. In those cases in which an artery arises from the sac, a growing use of intra-saccular flow-disrtuptors has been observed, such as the WEB, or, in case of aneurysms larger than 1 cm the use of Flow Diverter stents is being widely considered. In the latter case, there could be a potential risk of hypoperfusion in cortical territories supplied by the branch that is covered by the stent and should be used only in those cases not treatable with surgical approach.

Complex aneurysms, which include giant and dolichoectatic aneurysms, are difficult to treat because conventional clipping techniques often fail. Other techniques are required, like complex clip reconstructions, aneurysm transection with thrombectomy, and bypass techniques. A microsurgical experience with 3600 aneurysms, including 197 giant aneurysms, is reviewed to demonstrate these surgical techniques and associated outcomes. Excellent results can be achieved with surgery, whereas endovascular therapy is limited by high rates of incomplete aneurysm occlusion, recurrence, rehemorrhage, and retreatment. Bypass Surgery Intracranial-to-intracranial (IC-IC) bypasses are alternatives to traditional extracranial-to-intracranial (EC-IC) bypasses that reanastomose parent arteries, reimplant efferent branches, revascularize branches with in situ donor arteries, and reconstruct bifurcations with interposition grafts that are entirely intracranial. These newer bypasses represent an evolution in bypass surgery from using scalp arteries and remote donor sites towards a more local and reconstructive approach. We adopted a practice that utilizes IC-IC bypass preferentially when revascularization is needed in the management of complex aneurysms. Our experience with bypass for aneurysms was reviewed. During a 17-year period in which 3600 aneurysms were treated microsurgically in 2751 patients, 318 bypasses were performed, including 155 bypasses performed as part of aneurysm management and 70 IC-IC bypasses. Surgical techniques will be presented and associated outcomes were equivalent to traditional EC-IC bypasses. Adopting an IC-IC bypass approach requires experience in the operating room with simpler bypasses, confidence, and dedication to advancing the craft of bypass surgery. Surgical Approaches to Brainstem Cavernous Malformations Once considered inoperable lesions in inviolable territory, brainstem cavernous malformations (BSCM) are now surgically curable with acceptable operative morbidity. Recommending surgery is a difficult decision that would be facilitated by a grading system designed specifically for BSCMs that predicted surgical outcomes. Informed by our efforts to develop better grading systems for arteriovenous malformations (AVM), we hypothesized that a similar system might predict long-term outcomes and guide clinical decision-making. A consecutive, single-surgeon series of 130 patients was used to develop a grading system incorporating lesion size, location crossing the brainstem's midpoint, presence of developmental venous anomaly(DVA), age, and time from last hemorrhage to surgery. Rather than developing a grading system for all CMs that is weak with BSCMs, we propose a system for the patients who need it most. The BSCM grading system differentiates patients who might expect favorable surgical outcomes and offers guidance to neurosurgeons forced to select these patients.

Hans Henkes (Germany)

The introduction of flow diverting endovascular implants has revolutionized the treatment of intracranial aneurysms and influenced further treatment concepts. The today available flow diverters are dense braided mesh tubes with self-expanding features. The various products (SILK and SILK+, PED and PED FLEX, p64, FRED, SURPASS et al.) differ in material, radial force, flexibility, radioopacity and mesh density. Based on an institutional experience since 9/2009 in >600 patients treated with either PED (FLEX) or p64 or a combination thereof, the following conclusions can be drawn. Flow diversion (FD) is not a generic name, it is device specific. FD became our method of choice for the treatment of sidewall aneurysms. FD is less efficient for bifurcation aneurysms, but works well in selected situations. Fusiform aneurysms can be treated with FD, but their biology differs from saccular aneurysms, which has to be addressed. FD can be used in the anterior and posterior circulation. The treatment of acute and chronic neurovascular dissections and of direct carotid cavernous sinus fistulas benefits from the use of flow diverters. Large and giant aneurysms should be coiled either prior or during FD. The procedural complication rate is low. Dual antiaggregation is mandatory and has to be individualized. One year after FD, an efficacious flow diverter will have occluded >80% of all saccular aneurysms. In-stent stenosis is infrequent and a transient phenomenon in the majority of patients. Follow-up examinations and eventual re-treatment are essentialas with all other treatment modalities for intracranial aneurysms.

14.00-16.00 Spine Tumors and Metastasis

A.GENERAL The vertebral column is the most common location for bone metastasis and metastases are the most common tumors of the spine (HARRINGTON 1986 , SHAH et al. 2011 ). Osseous metastases are over ten times more common than primary bone tumors. In 50% of cancer patients bone metastases occur, 40-70% of which are found in the vertebrae. Ten percent of patients with a malignant neoplasm have vertebral metastases (SCHIFF et al. 1997) . In no less than 10-40% of these patients the metastatic lesions are responsible for the first symptoms, e.g. compression fracture or neurological symptoms. The presence of tumors cells causes osteoclastic and osteoblastic activation with subsequent osteolysis (70%), osteosclerosis (9%) or both (21%). The primary tumors are, in descending order, breast carcinoma, lung carcinoma, prostate carcinoma and gastrointestinal tumors (SCHICK et al. 2001 , HARRINGTON 1986 ). B.IMAGING Imaging has multiple purposes regarding metastases. In the first place imaging is used to detect lesions and assess their location. It can, however, also be very valuable in evaluation of different therapeutic options (ANDREULA & MURRONE 2005) . When it comes to detection of metastases in the osseous spine, MRI is more sensitive than MDP scintigraphy (ALGRA et al. 1991) . MRI is positive in 15% of negative bonescans and detects 20% more lesions in patients with positive bone scans. It will also be negative if there is no osteoblastic turnover within the lesion, as seen in some lung and breast tumors. Still bone scintigraphy has a relatively high sensitivity and is as such a useful tool for screening asymptomatic cancer patients. Since high osteoblastic turnover is absent in some lung and breast tumor metastases, some authors recommend MRI for screening (STEINBORN et al. 1999 , LAYER et al. 1999 . CT is not suited as a screening technique because of the use of ionising radiation. It can be used to confirm a suspected lesion on scintigraphy, showing trabecular or cortical bone destruction but also invasion of paraspinal tissues. MRI is the recommended imaging tool in case of neurological symptoms and is capable of whole spine investigation. Osteolytic lesions will display low signal intensity on T1-WI because of the high contrast of tumor (hypointense) with fatty bone marrow (hyperintese). A corresponding high signal on T2-WI is usually noted. On fat suppression sequences like STIR the hyperintense tumor contrasts nicely to the suppressed surrounding bone marrow, making this sequence very sensitive (MEHTA et al. 1995) . Furthermore negative STIR excludes metastasis and makes the use of a contrast medium unnecessary (MAHNKEN et al. 2005) . Another feature of lytic lesions is the loss of out-ofphase signal decrease. In contrast osteosclerotic metastases have low signal intensity on both T1-WI and T2-WI. In case of an infiltrating component a high signal on T2-WI may be seen. When the tumor destructs the vertebral cortex, the normal hypo intense vertebral lining is lost. After the administration of a gadolinium-chelate osteolytic metastases will enhance prominently, sclerotic lesions will show a more heterogeneous, peripheral enhancement. An advantage of the use of contrast is the improved evaluation of extraosseous components. The ADC calculated from diffusion-weighted MR images is probably a reliable parameter to distinguish vertebral metastases from normal vertebrae (HERNETH et al. 2002) . In a recent study Whole-body DW-MR imaging is said to be more sensitive in the detection of osseous metastases than skeletal scintigraphy and CT bone survey (DEL VESCOVO et al. 2014 ).

Multiple myeloma is a hematologic disorder characterized by the infiltration and proliferation of monoclonal plasma cells mainly in the bone marrow. The main symptoms are hypercalcemia, renal impairment, cytopenia/anemia and bone disease -summarized as CRAB-criteria. Symptomatic multiple myeloma is consistently preceded by asymptomatic premalignant stages called monoclonal gammopathy of undetermined significance and smoldering multiple myeloma. These stages also present with detectable monoclonal protein and/or monoclonal plasma cells in bone marrow but do not show any end organ impairment. Staging of multiple myeloma is based on the measurement of the monoclonal protein in serum and urine as well as the assessment of impairment of hematopoiesis, renal function and mineralized bone. In the last decade the development of novel therapeutic agents has led to an increase in response rates and survival time of patients with multiple myeloma, which further stresses the value of response assessment by imaging. Cross sectional imaging like MRI, CT and PET/CT is currently replacing conventional radiological surveys in the initial work-up and follow-up of patients with monoclonal plasma cell diseases. Recent studies demonstrate the added value of (whole-body) MRI to improve initial staging by unraveling a diffuse infiltration of bone marrow by plasma cells, a focal pattern or a combination of both. Also, PET/CT can detect response to therapy earlier than conventional response criteria. Furthermore, recent studies revealed that a complete remission of multiple myeloma confirmed by MRI or PET/CT goes along with a better prognosis compared to a complete response based only on serological parameters.

In 2013 it have been treated in Italy almost 170.000 patients with radiotherapy, in this number of patients 22.000 are bone metastases (13% of the total number of patients treated). The objectives of radiotherapy in this kind of patients are: -Preventing the onset of pathological fractures -To improve the mobility and function of the physical movement of the patient -Maintain an acceptable level of quality of life -Prolong survival (when possible) -But above all to relieve pain Pain relief is obtained in 75% -85% of cases with 30-50% of complete response. It is demonstrated that palliative radiotherapy improves pain and reduces functional interference in patients with painful bone metastasis improving all the daily activities of these patients (i.e. walk, work, sleep..). According ASTRO guidelines , based on an analysis of 4287 articles published from 1998 to 2009: -Various fractionation schedules can provide significant palliation of symptoms and/or prevent the morbidity of bone metastases -There is the evidence for the safety and efficacy of repeat treatment to previously irradiated areas of peripheral bone metastases.

-The use of stereotactic body radiotherapy holds theoretical promise in the treatment of new or recurrent spine lesions, although the Task Force recommended that its use be limited to highly selected patients and preferably within a prospective trial.

-Surgical decompression and postoperative radiotherapy is recommended for spinal cord compression or spinal instability in highly selected patients with sufficient performance status and life expectancy.

-The use of bisphosphonates, radionuclides, vertebroplasty, and kyphoplasty for the treatment or prevention of cancer-related symptoms does not obviate the need for external beam radiotherapy in appropriate patients.

Underling also the necessity of a multidisciplinary approach to this pathology.

Bassem A. Georgy (USA) In this presentation, the role of spine interventional procedures as a palliative treatment for spinal metastasis will be explored. Special emphasis will be placed on the value of cement augmentation in treatment of spinal metastatic compression fractures. A review of the biomechanical concepts and new classification of spinal stability will be presented. The rising role of combined radiofrequency ablation and cementation will be discussed in details. Other ablation techniques like cryoablation and PEEK implant will be also reviewed. Potential value of those techniques as adjuvant to the standard treatment options like radiotherapy, chemotherapy and surgery will be explored.

Aneurysmal Bone Cyst (ABC), represent approximately 1% of benign bone tumors. They are associated with vascular disturbance (trauma), and in one third to another primary bone lesion. Genetic studies relate them to USP6 fusion genes, marking ABC as neoplastic rather than reactive. The exact mechanism still remains unknown. Most difficult histopathologic differential diagnosis is from telangiectatic osteosarcoma. ABC are vascularized, multiloculated with daughter cysts. They occur in the first two decades of life, usually around the knee and femur. Spine locations are about 20 percent, involving thoracic and cervical, often situated in the posterior elements. In the spine, clinical manifestation includes pain and acute cord compression. Imaging findings show in X-Ray and CT, an eccentric, lytic, expansile lesion with fluid-fluid levels (blood), mostly apparent under MRI. There are multiple internal septa and cortical thinning. Most common treatment is surgical removal and bone grafting, although there is an important risk of recurrence. In these cases, the option of minimal invasive treatments is available. Initial endovascular arterial embolization reduces blood supply, allowing bone healing. Different agents have been used, to achieve distal and permanent effect. Another approach is direct intraosseous injection of sclerotics to destroy the vasculature. Additionally, injectable osteoconductive pyrophosphate materials are used, for primary bone stability. Other options include ablation, for vascular destruction and thrombosis. The strategy behind all these techniques is to destroy the abnormal vasculature and in the same time provide transient structural support to allow for bone healing, regeneration and recalcification of the pathologic area.

Osteoid osteoma (OO) is a benign bone tumor of childhood and adolescence. Ten percent of all osteoid osteomas are located in the spine. OO larger than 15 mm is denominated osteoblastoma (OB). OB is four times less frequent than OO and may have a more aggressive imaging and histological pattern. Therapy is required both in OO and OB because of severe bone pain independent from physical strain that typically worsens at night, especially in OO. Computed tomography (CT)-guided radiofrequency ablation (RFA) is an efficient method to treat OB, even in case of (juxta-)articular localizations. The successful treatment of OB Purpose: To declare death in a patient with coma, the absence of brain stem reflexes and breathing drive must be confirmed by neurological examination. In certain situations, termed as confounding conditions, complete and reliable clinical assessment cannot be performed. In such cases, ancillary tests confirming cerebral circulatory arrest (CCA) are helpful. The existing methods have a number of significant limitations. The advent of CT scanners capable of covering over 8 cm in z-axis (9.6cm z-axis coverage for the scanner used in this study, leading to the term "volume perfusion CT" [VPCT]) enables an assessment of the whole brain perfusion. This method would potentially constitute a better alternative to the existing ancillary tests. However, VPCT for the diagnosis of CCA has not been evaluated in a quantitative study up to date. The aim of the study was to assess the sensitivity of VPCT for the confirmation of CCA in the diagnosis of brain death (BD). Methods: The studied population was recruited from adult patients, who fulfilled the standard clinical criteria of BD. All subjects underwent VPCT using a 128-slice multidetector CT scanner. CBF and CBV values were calculated using deconvolution algorithm in ROIs covering brain stem, cerebellar hemispheres, cortico-subcortical regions of the frontal, temporal, parietal and occipital lobes and in the basal ganglia.

CCA was diagnosed in cases, in which CBF and CBV in all ROIs were below the well-known thresholds for neuronal necrosis: 12 ml/100g/min and 1.1 ml/100g respectively. Shortly after VPCT, a complete clinical testing for determination of BD was performed. Result: Thirteen patients (6 females) with a mean age of 54 years (17-78 years) were examined. VPCT confirmed CCA in 12 out of 13 (92%) cases. In these 12 cases CBF and CBV values in all ROIs were below the thresholds for necrosis. The detailed results are presented in Figure. In one patient (patient 11), who underwent decompressive craniectomy, VPCT showed critically limited, but persistent perfusion in the frontoparietal region and in the basal ganglia of the right hemisphere.

Conclusion: VPCT of the entire brain is feasible and highly sensitive test for the confirmation of CCA in the diagnosis of brain death. Purpose: Causes of subcortical hematoma can be divided into primary hemorrhages, such as hypertensive cerebral hemorrhage and amyloid angiopathy, and secondary hemorrhages, most commonly cerebral arteriovenous malformation (AVM) rupture. If there is cerebrovascular involvement, vascular lesions must be treated to prevent rebleeding or hematoma growth, so searching for the precise location of the source of bleeding as early as possible is essential. We performed a retrospective study on the capacity of 320-detector row computed tomography (CT) scanners to detect vascular lesions in cerebral subcortical hematomas, particularly using whole-brain four-dimensional CT angiography (4D-CTA Methods: We prospectively studied 41 patients aged between 23 and 91(mean 70±16) with symptoms of middle cerebral artery (MCA) occlusion within 9 hours of symptoms onset. Noncontrast CT (NCCT), CT-angiography and Perfusion-CT were performed in all patients. Either NCCT or MRI was performed during the follow-up, as control. For perfusion CT, colored CBV, CBF and TTP maps were generated. Two readers, one with 15-year experience in neuroradiology and one radiology resident, separately rated the Alberta Stroke Program Early Computed Tomography Score (ASPECTS), on NCCT, perfusion CT (CBV, CBF and TTP) as well as on control CT/MRI. Interobserver agreement was measured, for each imaging modality using weighted Cohen κ statistic. NCCT, CBV, CBF and TTP ASPECTS were correlated to final infarct extent based on control CT/MRI using Spearman rank test. The sensitivity and specificity were determined for both NCCT and PCT using the follow-up imaging as the standard of reference.

Result: The interobserver agreement was best for the TTP (κ =0, 81) and relatively poor for the NCCT (κ = 0.52) ( Table 1) . Also TTP showed the best correlation with control (r² = 0.75) ( Methods: 90 consecutive patients with symptomatic and asymptomatic high grade stenosis were treated by CAS. To shorten the procedure the filter was retrieved by the coaxial catheter together with the balloon as a guide. All patients were monitored for 24 hours after CAS by the neurointensive care unit and received a NIHSS score on the day before and after intervention. The patients were supposed to receive a MRI including diffusion and perfusion imaging on the day before and 1 to 3 days after intervention.

The angiological result was verified by ultrasound after 6 months. All patients were on sufficient double antiplatelet therapy at least one day before, verified by impedance aggregometry. Result: CAS was accomplished in all cases, and successful in 99%, 1 patient still had a high grade rest stenosis. 65% of the patients were symptomatic before. Most of them were treated 5 to 10 days after TIA / stroke. 6 hours after intervention no patient had a worsened NIHSS, 6 patients had improved in the NIHSS (p = 0.03) and 84 were unchanged. Mortality, major, and minor stroke until discharge were 0. Only 38 patients (42%) received the planned MRI before and after CAS. 14 patients (37%) showed new lesions of about 3 to 5 mm in the diffusion weighted MRI (11 patients 1 or 2 spots, 3 patients 3 and more). 2/3 of the lesions were within the borders of the initial perfusion deficit. Perfusion was ipsilaterally normalized except in previous infarcted areas. 13 % of the patients had restenosis > 50% after 6 months, no surgical or endovascular therapy was performed. Methods: Endovascular recanalization was attempted in 14 patients with symptomatic 11 ICA occlusions and 3 VA occlusions. The duration of the occlusion ranged from 10 days to 6 months (mean, 2.5 months), and the mean length of the occlusion was 95 mm. Cerebral hemodynamics ipsilateral to the side of the occlusion were severely impaired in all patients. The endovascular procedure was performed under total cerebral circulatory protection, beginning with proximal protection with a subsequent switch to distal protection (in 11 cases ) after successful guide wire passage. Result: The occlusion was recanalized successfully in 12 out 14 of patients (85.7%), resulting in improvement of ipsilateral cerebral hemodynamics without symptomatic stroke. Small asymptomatic ischemic lesions were detected in 3 of 14 patients (21%) on DWI, and 1 patient developed a mild groin hematoma. Ischemic episodes did not recur during the mean follow-up period of 19 months. However, 2 patients experienced asymptomatic reocclusion, which was retreated successfully without complications due to failure maintenance of antiplatelet and anticoagulant therapy. Purpose: Inflammation of the periodontal space is a common chronic disease of the teeth apparatus, which leads to resorption of the alveolar bone. Periodontitis is the second most frequent disease of the mouth. The association between periodontitis and atherosclerosis has already been shown in many studies. Many risk-factors for the periodontal disease are also proatherogenic and therefore it is difficult to proof if periodontitis acts directly as an indipendent risk-factor for atherosclerosis. In this retrospective computer-tomography (CT) study we analysed a possible causal relationship between periodontitis and atherosclerosis of the carotid artery (CA). Methods: CT-angiographies of the head and neck region of 71 patients were retrospectively analysed (GE VCT-64, SD:0,625mm, I:0,4mm, 80kV, 375mA). Patients were divided in two groups on the basis of signs of advanced periodontitis in bone window (peridontitis: n=36; 20men; mean age 69±12yno periodontitis: n=21; 7men; mean age 65±14y). Patients without teeth (n=14) were excluded. Atherosclerosis and stenosis of the CA at the bifurcations were quantified. For each patient cardiovascular risk-factors, as arterial hypertonus, hyperlipidemia, diabetes mellitus and nicotin abuse, were documented. Result: The two groups did not show any differences in cardiovascular risk-factors. Atherosclerosis at the carotid bifurcation was significantly more frequent in patients with periodontitis (p<0,01), with an higher prevalence of stenosis >50%. In the periodontitisgroup 20 of 36 patients had a stenosis >50% at the origin of the internal carotid artery (ICA), 6 of them bilateral. In the controlgroup without signs of peridontitis only 1 of 21 patients showed a single proximal ICA stenosis >50% (p<0,01). Patients with periodontitis showed a mean stenosis of the ICA of 59±20%, more often with mixed atheromatous plaques (75%) and less frequently only calcified plaques (20% The examinations were carried out twice within the following periods: in the course of the first two weeks (at the time of admission), and after two months. The size of an internal lumen of an artery at the level of dissection was measured, degree of the stenosis was evaluated.

Result: in the first study lumen stenosis of internal carotid arteries was revealed in 60 % of cases (15 arteries) lumen stenosis of vertebral arteries was revealed in 90% (35), occlusion in 40% (10) and 5 % (2), respectively. After statistical analysis of the data with the use of nonparametric statistical methods (Wilcoxon test) it was revealed that the lumen diameter value of the dissected stenotic arteries in the first study is lower than in the second study (p<0,05). When occlusion occurred a spontaneous recanalization of vertebral arteries was revealed in 50% of cases, spontaneous recanalization of internal carotid arteries was revealed in 40 % of cases. Residual stenosis is considered hemodynamically insignificant in all cases Conclusion: Cerebral arteries dissection is a dynamic process, stenosis is completely or partially resolved in all cases in two months. As opposed to that fact occlusions are resolved in less than a half of cases and the residual stenosis is considered hemodynamically insignificant. Keywords cerebral artery dissection, acute stroke, artery recanalization 1st Part: Neuroradiology and interventional neuroradiology practice in Tunisia

The aim of the presentation will be to present Neuroradiology and Interventional Neuroradiology practice in Tunisia. A brief review of the human and material resources and reference's centers will be made. Residency curriculum and specific training in neuroradiology and it interventional side will also be exposed. Spinal infections are rare. The incidence of acute hematogenous nontuberculous vertebral osteomyelitis is estimated to be 5-5.3 patients per million patients per year with a male predominance. An increase in vertebral osteomyelitis has been noted during the last 15 years, probably as a result of the evolutions in diagnostics principally MRI.

In adults, the disk is avascular and the organisms invade the the vertebral body using arterial stream, then passing into the disk by continuity. There is increased risk in the elderly, patients with diabetes, and immunodepressed patients. Magnetic resonance imaging (MRI) is the imaging procedure of choice in diagnosing spinal infections.[ Its sensitivity, specificity, and accuracy rates approach 96, 92, and 94%, respectively, and it is unique in detecting soft tissue involvement. Contrast enhancement in MRI could be useful the better define the exdtension of the lesions, especially the epidural involvement. CT could integrate the MRI giving information on the bone aspects of the disease and eventual cortical lesions, and indispensabile in performing guided vertebral biopsy. We have few criteria to differentiate pyogenic and nonpyogenic vertebral osteomyelitis using imaging . Pyogenic disease is characterized by moderate paraspinal abnormal soft tissue, (perisomatic collar), early involvement of the disk for erosion of end plates, and anterior-posterior vertebral involvement.

In TB the involvement of contiguous vertebral bodies use the anterior longitudinal ligament with late disk diffusion, and peduncles extension, producing spinal deformity. In brucellosis, there is moderate paraspinal soft tissue, diffuse but solely anterior part involvement (parrot beaks), and no spinal deformity.

Conventional infection-imaging radiopharmaceuticals, such as labeled leukocytes (WBC) can fail in the detection of vertebral osteomyelitis, and the site of infection often appears as a "cold spot" in the scan. 18F-FDG or combinations of 99mTcdiphosphonate with 67Ga-citrate scintigraphies can be used. The first studies of 18F-FDG PET utilization in patients with vertebral infection have shown high sensitivity but variable specificity (35.8%-87.9%). FDG-PET was at the beginning a promising technique for the diagnosis of bone infections based on the intensive consumption of glucose by mononuclear cells and activated granulocytes. 18F-FDG seems to be a good radiopharmaceutical showing high sensitivity and specificity but unfortunately its use may have limitations in distinguishing uncomplicated bone healing from osteomyelitis. Furthermore, 18F-FDG as well as 99mTc-diphosphonate with 67Ga-citrate, suffer from some other limitations as non-negligible radiation burden, long acquisition time and high costs. Radionuclide imaging is however strongly recommended to assess disease activity during follow-up after medical therapy. Due to low specificity for vertebral infection of the commercially available radiopharmaceuticals, alternative experimental radiotracers, such as radiolabeled antibiotics (99mTcciprofloxacin) and radiolabeled vitamin (111In-Biotin) have been developed, in particular 111In-Biotin scintigraphy has shown very high sensibility (90%) and specificity (93%) to detect early vertebral infection in a large consecutive series of patients. 111In-Biotin scintigraphy, with SPECT/CT acquisition, has shown permanent high values of accuracy other than the advantage to distinguish bone involvement from soft tissue involvement infection.

Although the results obtained in preliminary studies are highly encouraging, full validation in the clinical setting requires further large-scale studies.

The management in acute, subacute and chronic spine infection seems an easy topic but in the reality there are still multiple questions that are not yet clearly define regarding the first diagnosis, the identification of the pathogenic agent, how and when to perform spine biopsy and how to evaluate the results of the treatment. The clinical findings in those patients is often aspecific (spine pain) and X ray of the Lumbar spine is always suggested as first diagnostic approach. Abnormal lab tests are also present as increase value of ESV and PCR. MR has certanly an higher sensitivity and specifity a than CT especially in early stage. CT can be useful in this phase to confirm the diagnosis and exclude other pathology. Suchondral edema is evident in multiple MR sequences in an early phase, and the visibility of a paravertebral fluid collection is obviously evident with both MR and CT. Biopsy is mandatory and needed to identify the pathogenic agent and it is suggested to perform it a at least five days after the interruption of antibiotic therapy.

Once the biopsy has been performed, the material must be sufficient to lead and to exclude all the differential diagnosis. University of Tübingen, Tübingen, GERMANY Purpose: We sought to investigate the feasibility and the added value of in-vivo Amide proton transfer (APT) MRI combined with MRspectroscopy(MRS) and positron emission tomography (PET) for the comprehensive metabolic mapping of gliomas.

Methods: Fourteen patients with newly diagnosed gliomas (WHO grade 2-4) were prospectively recruited and underwent simultaneous MR-PET imaging, including proton MRS (echo time 135 ms) and 11-C-methionine on a 3T whole-body clinical MR-PET scanner.The acquired metabolic maps and the normalized ratios of the tumor metabolic activity in hot-spots were statistically compared and correlated to the histopathological grading. Result: Six of the examined gliomas were low-grade (WHO grade 2), 7 were high-grade (3 with WHO grade 3 and 4 with WHO grade 4 tumors).

The histopathologic examination in one patient revealed inflammation . The choline MRS images showed hot-spots in all cases except of the inflammation. The MRS hot-spot had a significant (>70%) spatial overlap with the APT-images in all but two cases with WHO grade4 tumor, where the overlap was<50%. The APT signal in the inflammation as well as in 2 patients with lo-grade gliomas was not enhanced compared with NAWM. Two patients with low-grade tumors demonstrated significant APT and PET enhancement. The PET images did not demonstrate any hotspot in nearly all cases with low-grade gliomas and in two cases with WHO grade 3 glioma. The normalized choline ratio in high and low-grade tumors was 2.7± 0.4 and 1.5±.3, respectively. The relative enhancement in APT was 60±13% and 10±25% for high-and low-grade gliomas. Finally, the PET relative enhancement was 50±18% and 7±23% for high-and low-grade gliomas, respectively. In total the imaging findings in MRS, APT and PET were concordant for almost all high-grade gliomas showing a remarkable interchangeability between the techniques. The MRS and APT techniques in combination provided in all case of lowgrade gliomas adequate image contrast that enabled biopsy of the metabolic hot-spot. Conclusion: Our initial results show that the implementation of APT, MRS and PET on hybrid MR-PET imaging is feasible for comprehensive metabolic mapping with the potential to increase the diagnostic accuracy and aid in staging and surgical planning for patients with brain tumors. Result: Intraoperative RS-fMRI in anesthetized patients proved to be feasible and analysis revealed no significant differences in preoperative z-scores between the sensorimotor areas ipsi-and contralateral to the tumor. Significant decrease of z-scores (P<0.01) was shown in patients with postoperative neurological deficits. The ipsilateral intraoperative zscore had a significant negative correlation with the degree of paresis immediately after the operation (r=-0.67, P=0.0001) (short-term paresis) and after the discharge from the hospital (r=-0.65, P=0.0001) (mid-term paresis). ROC curve analysis demonstrated moderate prognostic value of the intraoperative z-score (AUC: 0.84) for the mid-term paresis score. The contralateral to tumor z-scores (pre-and intraoperative ones) were not significantly correlated to the short-and mid-term clinical findings. Purpose: We hypothesized that the quantitative apparent diffusion coefficient (ADC) value within a voxel containing viable tumor may change or remain stable after concurrent chemoradiotherapy, reflecting tumor progression or stable disease. Accordingly, evaluation of serial differences in ADC using parametric response map (PRM) analysis maybe more sensitive than single time point ADC for the prediction of treatment response in glioblastoma patients. Therefore, the purpose of this study was to determine the diagnostic superiority of apparent diffusion coefficient (ADC) parametric response (ADCPR) for predicting glioblastoma treatment response, compared to single time point measurement.

Methods: 50 post-treatment glioblastoma patients were enrolled. ADCPR was calculated from serial ADC maps acquired before and at the time of first detection of an enlarged contrast-enhancing lesion on voxel-by-voxel basis. The percentage-decrease in ADCPR and 10% histogram cutoff of ADC (ADC10) were compared as potential predictors of treatment response at subsequent 3 months and 1 year follow-up studies.

Result: The percentage-decrease in ADCPR was significantly higher in progression group than in stable-response group both at 3 months follow-up studies (p <.001) and at 1 year follow-up studies (p =0.003-0.002). ADCPR significantly improved area under the receiver operating characteristic curve from 0.67 to 0.88 and from 0.70 to 0.92 for both readers, respectively, compared to ADC10 at 3 months follow-up studies but did not significantly improve at 1 year follow-up studies. The interreader agreement was higher for ADCPR than ADC10 (intraclass correlation coefficient, 0.93 versus 0.86). Conclusion: Voxel-based ADCPR appears to be a superior potential imaging biomarker to single time point measurement of ADC for predicting early treatment response in glioblastoma patients who showed enlarging contrast-enhancing lesions during the follow-up study. Therefore, PRM analysis may provide more accurate information for the prediction of patients likely to progression on short-term follow-up, thereby improving treatment selection and patient outcome. Purpose: Amide proton transfer (APT) imaging by means of chemical exchange saturation transfer (CEST) has been proposed as an adjunct to conventional MRI, specifically to distinguish high from low grade glioma and to differentiate between tumour recurrence and radiation injury. With data currently confined to high field imaging, animal models, and/or limited parenchymal coverage, the purpose of this study is to assess APT imaging in a clinical setting. Methods: Patients under follow up for histopathologically proven glioma were considered eligible with informed consent obtained in all. Exclusion criteria were lesions <1cm and large susceptibility artefacts. Imaging was performed using a 3T 3DGRE CEST sequence (Achieva, Philips, Best/NL) with 38 alternate offsets running from +/-4.5ppm to 0 and B1 power of 2uT. Ten 5 mm slices were acquired in 7:30 mins supplemented by conventional volumetric sequences. Colour display (window of +/-5%) voxel-wise APT maps were obtained by calculating MTR asymmetry with a corrected spectrum at an offset of 3.5 ppm. For quantification, one region of interest (ROI) was placed in a representative tumour slice with a comparative ROI in contralateral normal appearing white matter (NAWM). Result: Ten patients were prospectively included in 2014/15 (WHO grade II in 3, III in 3, and IV in 4) following standard treatment by surgical resection, with or without radiation and/or chemotherapy. The APT sequence coverage was overall sufficient for tumour imaging. APT maps could be constructed in 8 patients: In 1 patient excessive artefacts, and in another incomplete data prevented mapping. Most APT maps showed artefacts in the periventricular area, presumably reflecting CSF pulsation. High APT signal was evident in enhancing lesions, in T2w-hyperintense areas and occasionally remote from the primary in NAWM. Notably, high APT signal was also seen in resection cavities. (37), to other post-contrast enhancement perfusion methods (10), to the lesion morphology, and to follow up results (12). The normalized rTBF values for the lesions in the same anatomical region were compared, at the significant level set to p<0.05. Result: The pcASL method allowed characterizing all the enrolled lesions. Moreover, there was a significant rTBF difference between cerebellopontine angle schwannoma and meningioma and between schwannoma and metastasis. For pituitary lesions, there was a significant difference between pituitary adenoma and meningioma. For jugular foramen region, there was a significant difference between paraganglioma, chondrosarcoma, and cholesteatoma. Interestingly, one case of osteomyelitis, showed a pseudotumoral increased rTBF, and a plasmocytoma under treatment, showed low rTBF, in relation with treatment response. Conclusion: The present preliminary study shows the interest of pcASL-MRI in evaluating tumor perfusion in the tumors that are located in the skull-base region. Moreover, pcASL can be helpful in the differential diagnosis of the tumors in this region without using contrast materials. Purpose: To perform a systematic literature review and meta-analysis of the diagnostic value of relative cerebral blood volume (rCBV), normalised apparent diffusion coefficient (ADC), and the spectroscopy metrics choline/creatine (Cho/Cr) ratio and choline/N-acetyl aspartate (Cho/NAA) ratio as imaging biomarkers for brain gliomas and metastases differentiation.

Methods: Using the PRISMA method, 79 articles from 2000-2013 were selected from the NCBI database for systematic review, from which 24, 22 and 8 articles were selected respectively for spectroscopy, rCBVand nADC meta-analysis. We used random effects model to obtain weighted averages and area under receiver operator characteristic (ROC) curve for thresholds between high-and low grade gliomas (HGG, LGG) and metastases. Purpose: Treatment of brain arteriovenous malformations associated with high-flow fistula is still challenging assignment by means of stereotactic radiosurgery and surgical treatment. Although AVMs accompanied by high flow fistula increase the incidence of perioperative complications, many endovascular innovations make treatment of AVM advance. Therefore, the endovascular occlusion of those high-flow shunts plays an important role in complete obliteration of AVM with multimodal therapy. We report two cases of AVM with different type of fistula, which were treated with double arterial catheterization technique with coils. Methods: Two male patients in their forties have brain arteriovenous malformations associated with high-flow fistulas. One was detected cerebral AVM with fistulous component incidentally and another presented with intracranial hemorrhage. The latter harbored a high-flow fistula neighboring nidus. Fistulas of both patients were occluded with coils and glue by double catheters technique and niduses were embolized with staged manner. Two Marathon Flow Directed Microcatheters(Covidien, Irvine, Calif) were delivered just proximal or beyond the fistula in a same feeder and through one catheter ED coil(Kaneka Medix Co., Osaka, Japan) placed near fistula and keep the coil undetached. The flow of feeding artery was reduced significantly because of the coil and fistula was occluded with coils and glue from another catheter safely. Result: ED coils have so flexible delivery wires enough to place the coils through Marathon catheter, which was navigated to long tortuous feeding artery. Obliteration of high flow shunt was acquired by double catheter technique without difficulty. No additional neurological deficit was occurred after obliteration of fistula and embolization of nidus. Surgical removals were followed in two weeks after final embolization resulted in excellent outcomes. Purpose: Meningiomas are the most common benign intracranial neoplasm. Surgical excision is the mainstay of treatment. They are mostly hypervascular and preoperative endovascular embolization is aimed at reducing blood supply via the dural arterial feeders, but there is no consensus on the indications and this procedure is a controversial topic. Aim of this study is to review our single-center experience to assess the efficacy of the endovascular technique. Methods: We retrospectively compared patients with intracranial meningiomas who underwent preoperative embolization (with particles of polyvinyl alcohol) followed by radical resection (group 1), with a control group of patients operated without preliminary embolization (group 2) at our institution from January 2006 to June 2014. Comparisons between groups were made on the basis of surgical time and intraoperative blood loss in order to assess the usefulness of the endovascular procedure.

According to the rate of tumor devascularization we identified 4 subgroups in the group 1 (0-24%, 25-49%, 50-74%, 75-100%).

Result: 80 patients underwent preoperative embolization (POE) whereas exclusive surgical resection was performed in 111 patients. Overall, no significant differences in intraoperative blood loss and surgical time were showed between the 2 groups. Nevertheless a subgroup analysis showed a significant reduction in the surgical time in subgroup 4 of group 1 (p<0.01).

Only 3 cases of minor complications occurred with embolization. Conclusion: POE after accurate assessment of tumor vascularization in patients with intracranial meningiomas is safe and effective in reducing surgical time in selected cases when > 75% of devascularization is achieved. However, the overall effect of POE on surgery and the added risks of this procedure do not justify its routine use as standard practice in the management of meningiomas. Purpose: Minimally invasive treatment of spinal metastatic lesions has been limited by access and tumor location. Concerns of tumor extravasation and post radiation therapy fracture have recently advocated for a combined tumor ablation before cement augmentation. Tumor debulking has been advocated in recent reports before cementation. This study reports multicenter clinical and imaging outcomes following t-RFA and cement augmentation in spine malignant lesions. Methods: An IRB approved retrospective multicenter study of 74 patients (106 vertebral lesions) with spinal metastatic lesions evaluated an articulating bipolar RF ablation system designed for minimally invasive procedures in the axial skeleton with thermocouples embedded along the length of the articulating segment to real-time assess the size of the ablation zone. Visual Analogue Pain score (VAS) and Oswestry Disability Index (ODI) were obtained pre-and 2-4 weeks post-treatment. Pre and post procedure MRI and PET scans were also evaluated. Result: Myeloma, breast, lung cancer comprised 31%, 26% and 20% of tumor etiology, respectively. All procedures were performed safely with no complications or thermal injury. Mean ablation time was 3.5 ± 2.2 min (range 1 -15). Mean volume of cement delivered was 3.0 ± 1.1 cc (range 1-6). Mean VAS scores dropped from 8.1 ± 2.3 pre-procedure to 3.5 ± 2.6 post-procedure (p<0.0001). Mean ODI scores improved from 29.3 ± 11.2 to 18.4 ± 10.3 post-procedure (p<0.0001) representing a categorical and clinically significant (>10%) improvement in disability. A predictable pattern of decreased tumor volume and an enhancing rim was observed in post contrast MRI imaging after ablations procedures in 13 lesions imaged. All metabolically active lesions in pre procedure PET scan (8 lesions) showed decrease activity after ablation. Similar findings were also seen in bone scan (3 lesions) Conclusion: t-RFA followed by vertebral augmentation in malignant spinal lesions resulted in pain and functional status improvement, with no significant complications. Articulation permitted reproducible transpedicular access to vertebral lesions regardless of location. TCs allowed accurate monitoring of the ablation zone to avoid complications of nearby neural elements. Post procedure MRI and PET could be helpful to monitor tumor growth in determining response and timing of adjunctive therapy.

Metastasis,Radiofrequency ablation,Spien Purpose: One of the main risks associated with vertebral augmentation is cement leakage and the potential damage this may cause. A proposed benefit of kyphoplasty is that it may help reduce leakage by creating a void into which low viscosity cement can be injected under low pressure so that cement is localised to the site of fracture. This study investigated whether differences in cement distribution within the vertebral body were apparent after vertebroplasty and kyphoplasty were used to treat severe vertebral compression fractures. Methods: Pairs of thoracolumbar "motion segments" from seventeen cadavers (70-97 yrs) were compressed to failure in moderate flexion and then cyclically loaded using a technique that consistently created severe vertebral wedge deformity in one of the vertebral bodies. One of each pair of motion segments from the same spine underwent vertebroplasty and the other kyphoplasty. For both treatments, a bipedicular technique was used which involved injecting 7 ml (3.5 ml per pedicle) of treatmentspecific cement into the centre of the vertebral body, adjacent to the depressed endplate. Specimens were then creep loaded at 1 kN for 1 hour to simulate mobilisation after treatment. The augmented vertebral body then underwent micro-CT scanning to quantify and compare regional cement distribution. Result: Percentage cement fill for the whole vertebral body showed no significant difference between treatments (vertebroplasty:19.8%, kyphoplasty:18.0%). However, regional differences were apparent. Pooled data for both groups showed a greater percentage fill in the anterior than posterior half of the vertebral body (26% vs 13% respectively, P<0.001) and in the middle compared to superior (P<0.001) and inferior (P<0.001) thirds (29% vs 14% and 11% respectively). Comparisons between groups showed that posterior fill was greater following vertebroplasty than kyphoplasty (16% vs 10%, P<0.001), as was fill in the inferior third of the vertebral body (14% vs 9%, P<0.001). Conclusion: Greater posterior and inferior cement fill following vertebroplasty suggests a more widespread distribution of cement. Successful vertebral augmentation requires accurate placement of cement that is localised at the site of fracture to support the depressed endplate, and these results suggest that kyphoplasty is better able to achieve this. The purpose of this study was to determine the effect of the injectable calcium sulphate / hydroxyapatite bone composite on the fracture rate of the "sandwich vertebra" in the treatment of osteoporotic VCF. Methods: We performed a prospective study of all consecutive patients with sandwich level fractures, who underwent vertebroplasty with a calcium sulphate / hydroxyapatite composite between december 2010 and october 2014 (10 patients). Fracture rate of the sandwich vertebra after vertebroplasty was noted and vertebral height in the immediate postoperative period and the one year follow up were compared. The level of pain was always evaluated by the VAS-scale at the moment of augmentation procedures, after about two week from the augmentation and at the final follow-up. Result: In 10 consecutive cases only one adjacent fracture of a sandwich vertebra was noticed. There was no or a slight decrease in vertebral height in 9 patients while only in a patient a fracture of the sandwich vertebra was seen after about three week from the first treatment. The mean pain level was included between 7 and 10 in the VAS Scale at the moment of augmentation treatment, decreasing in a range between 4 to 7 after about two week while after one year the VAS Scale was in a range 0-3. Cerebral microbleeds (CMB) are found in a significant proportion of the normal elderly population. The detection of cerebral microbleeds is strongly influenced by the MR parameters used, susceptibility-weighted imaging (SWI) being more sensitive than T2* weighted imaging. Numerous medical conditions have been associated with cerebral microbleeds but the two main aetiologies are two distinct types of small vessel disease: hypertensive arteriopathy and cerebral amyloid angiopathy (CAA). The regional distribution of the CMB is a key factor for distinction between these two entities. In hypertensive small vessel disease the CMB are predominantly infratentorial and in the basal ganglia, whereas in CAA their location is more peripheral, often in the parietal and occipital lobes. More recently other imaging features of CAA have been described. These include cortical superficial siderosis (cSS), enlarged perivascular spaces in the centrum semi-ovale, and confluent white matter hyperintensities in the posterior part of the brain. Clinical presentations of CAA include symptomatic intracerebral (lobar) haemorrhage, focal transient neurological symptoms, cognitive impairment, and in some cases rapidly progressive cognitive and neurological decline. The latter can be associated with an inflammatory response, showing vasogenic oedema on MRI that improves after steroid treament. The distinction between hypertensive arteriopathy and CAA, based on the distribution of CMB and additional imaging features of CAA is clinically important as the two conditions differ in their prognosis and are likely to impact on treatment choices in future. Recurrent haemorrhage is more frequent in CAA, particularly in there is also evidence of cSS. Treatment with antiplatelet, antithrombotic and thrombolytic agents appears to carry a higher risk of symptomatic haemorrhage in patients with CAA.

Accurate and timely diagnosis of dementia is important to guide management and provide appropriate information and support to patients and families. Currently, with the exception of individuals with genetic mutations, postmortem examination of brain tissue remains the only definitive means of establishing diagnosis in most cases, however, structural neuroimaging, in combination with clinical assessment, has value in improving diagnostic accuracy during life. Beyond the exclusion of surgical pathology, signal change and cerebral atrophy visible on structural MRI can be used to identify diagnostically relevant imaging features, which provide support for clinical diagnosis of neurodegenerative dementias. While no structural imaging feature has perfect sensitivity and specificity for a given diagnosis, there are a number of imaging characteristics which provide positive predictive value and help to narrow the differential diagnosis. While neuroradiological expertise is invaluable in accurate scan interpretation, there is much that a non-radiologist can gain from a focused and structured approach to scan analysis. In this article we describe the characteristic MRI findings of the various dementias and provide a structured algorithm with the aim of providing clinicians with a practical guide to assessing scans.

Extrapyramidal disorders can be classified as pathologies that affect basal ganglia (caudate, putamen and globus pallidus), subtalamic nucleus and structures that are functionally connected with them (substantia nigra). On histological level affected tissues exhibit high level of deposits of paramagnetic ions (presumably iron and copper) and loss of neural tissue. In turn this is manifested in loss of volume of brain structures and dysfunction of specific neural tracts. Imaging techniques were focused on tracing of those changes. Parkinsonism refers to any condition that causes a combination of the movement abnormalities resulting from the loss of dopaminergic nerve cells in substantia nigra pars compacta. Beside idiopathic Parkinson's disease (PD), a several conditions fulfill definition-such as Progressive supranuclear palsy (PSP), Multisystem atrophy (MSA), Corticobasal degeneration (CBD) and other extrapyramidal disorders ( Wilson's disease, Huntington's disease and Pantothenate kinase-associated neurodegeneration). Magnetic resonance imaging (MRI) is primary choice since it provides morphological, structural and physiological insight in changes caused by extrapyramidal disorders. Positron emission tomography (PET) gives additional information about physiological changes by using neurotransmitters labeled with positron emitters. Computerized tomography (CT) has limited possibilities which are restricted to assessment of morphological changes.

An emerging issue in neuroimaging is to assess the diagnostic reliability of PET and its application in clinical practice. Moreover, there is a urgent need for reliable biomarkers in neurodegenerative diseases. Parkinsonian Syndromes are defined clinical entities but the appearance of symptoms occurs years or decades after the first neuropathological changes take place in the central nervous system. Furthermore, the early stages of the diseases are often difficult to be diagnosed since symptoms might be common. As for Movement Disorders the role of 18 Ffluorodeoxyglucose-and 18F-dopamine-positron emission tomography (FDG-PET and F-DOPA-PET, respectively) is to help the clinicians to perform reliable diagnoses as well as differential diagnoses between the main types of such degenerative disorders disclosing the characteristic patterns of pathophysiological changes peculiar for each of them. PET reflects changes in synaptic activity in brain: correlated metabolic and neurotransmitter changes in specific regions might provide an index of neuropathological processes. Moreover, cognitive changes often anticipate or accompany disease progression and their detection in association with the disorder and the relative neurobiological changes is of utmost importance. Large databases of patients with movement disorders and healthy controls as investigated by PET along with expert analyses systems (voxel-based analyses and scripts extracting and processing automatically data from volume of interest-based atlases) might assist clinicians in improving diagnostic accuracy and accelerate image analysis time.

The presentation will describe FDG-PET and F-DOPA-PET findings in Parkinsonian Syndromes highlighting the differential distribution patterns of the radiotracers and their clinical impact.

Thalamotomy is effective in alleviating tremor caused by certain movement disorders. Surgical treatment options are available for patients with debilitating medication-resistant tremors. These include ablation methodologies such as using a Gamma knife and stimulation methodologies such as deep brain stimulation (DBS). A few targets within the basal ganglia are beneficial in control of tremor. The most effective target is the ventral intermediate thalamic nucleus (VIM), MRI-guided focused ultrasound (MRgFUS) is an innovative technology that enables non-invasive intracranial focal thermal ablation within the central nervous system, with promising preliminary results.5-7 A 1024element, phased-array ultrasound transducer is used to heat and ablate the desired anatomical target only a few mm in size. Lesions are generated by gradual focal heating with the location and temperature controlled and monitored by the MRI system. During the initial reversible low temperature focal heating, patients are observed for transient positive and adverse clinical effects prior to irreversible high temperature ablation. The treatment's impact on the tremor is monitored clinically during the procedure. We have treated 16 Parkinson's Disease and essential tremor patients with medication-resistant severe refractory tremor, between November 2013 to March 2015: mean age 69.4±8.1 years (range, 51-79) with a mean disease duration of 15.2±11.6 years (range, 2-35). The treatment consisted of a ventral intermediate nucleus thalamotomy contralateral to the more disabled side, aimed at controlling the hand tremor. Results: All patients significantly improved and were tremor free immediately after the procedure. Adverse events during MRgFUS included: headache, dizziness, vertigo, and lip paresthesia; following MRgFUS adverse events were: hypogeusia, unsteadiness when walking, and disturbances when walking in tandem. Most of the side effects resolved within one week following treatment.

Conclusions: Thalamotomy using MRgFUS is safe and effective in Parkinson's Disease and essential tremor patients. Large randomized studies are needed to assess prolonged efficacy and safety.

Diagnosis of patients with cognitive impairment and/or abnormal movements, or motor impairment remains a clinical challenge today, and imaging has added substantially in this regard during the past decades. Structural imaging, mainly with MRI, and the various options/sequences it implies, and functional studies, mainly those with Nuclear Medicine techniques, but also some using MR (as Arterial Spin Labelling) have become a fundamental part of the diagnostic work-up today in tertiary referral clinics. Characteristic imaging findings have been described in conditions such as the various forms of fronto-temporal lobar degeneration, or in the previously-called "atypical parkinsonisms", thus adding to the well-described, clinical phenotypes of these and other entities. However, as the field of neuroradiology developes, and knowledge in our field increases, bridging with knowledge in areas such as genetics, pathology, or molecular biology, neuroradiology continues challenging previously established clinico/pathological concepts, and the frontier beween entities becomes more diffuse in some instances. As an example, this is the case for patients having cognitive decline and abnormal movements, or for patients presenting with cognitive decline and intracranial haemorrhage/cerebral amyloid angiopathy (CAA). A few cases illustrating typical findings in certain conditions, as well as some cases showing atypical imaging, are presented and discussed with the audience. The aim is to somehow illustrate the capacity of neuroradiology to demonstrate that there may be a gray-scale between pathologies, and thus, to challenge established knowledge.

10:30-12.00 Intracranial Vessel Evaluation Beyond Morphology

High-resolution vessel wall MRI is an emerging technique for characterizing intracranial arterial disease. It can be used to differentiate and characterize luminal narrowing and can subdifferentiate different components of arterial atherosclerotic plaque. Large artery CNS vasculitis is associated with arterial wall thickening and enhancement. Reversible vasoconstriction syndrome is characterized by wall thickening without enhancement and arterial dissection can be identified by their intramural methemoglobin content. In recent years, aneurysmal diseases have demonstrated to be at least in part related to inflammatory changes within the vessel wall and may thereforealso be amenbale to dedicated vessel wall imaging. Finally, ultrathin scanning fiber endoscopes have allowed us to visualize the arterial wall from within the lumen adding to our understanding of the integrity of the endothelium and the healing processes following different endovascular treatments. In this review the technique and applications of vessel wall imaging will be described.

Arterial Spin Labeling (ASL) is a MRI technique for quantitative evaluation of brain perfusion, measuring directly the CBF. There are a wide range of ASL sequences, which are completely noninvasive, not needing any exogenous tracer, using the blood as an endogenous tracer. ASL measurements can be repeated as many times needed and have excellent temporal and spatial resolutions. The two major common steps for ASL techniques are: the labeling and the readout. Initially, the water blood molecules are labeled magnetically by applying a radiofrequency inversion pulse. After a period time (arterial transit time) the labeled blood reaches the region of interest and the brain images are obtained. The difference between the images obtained with (tag) and without (control) labeled blood, produces the perfusion map. There are many different labeling schemes (CASL-continuous_ASL, PASL-pulsed_ASL, pCASL-pseudo-Continuous_ASL, Vessel-selective-VSASL, Velocityencoded-VEASL) and readout sequences available. The major ASL techniques limitations are the low signal-to-noise and the dependent on the arterial arrival times, which may be altered in several diseases, namely the cerebrovascular diseases. ASL has been used for the evaluation of vascular territories and collateral circulation, to evaluate the brain perfusion in acute stroke and arterial stenosis / occlusion, and to depict AVMs and dAVFs. ASL has also evaluated the cerebrovascular reactivity. ASL is also suitable for tumor characterization and grading. ASL has also been used in the evaluation of neurodegenerative diseases and epilepsy. This lecture wills overview the basic principles of ASL techniques and the major clinical applications.

12:00-13.00 Diagnostic Special Focus in MS ESNR MAGNIMS Joint Session

The diagnosis of multiple sclerosis (MS) remains challenging in some cases, as there is no single test (including biopsy) that can provide a definite diagnosis. However, with the availability of expensive diseasemodifying treatments that are thought to be particularly effective in the early phases of the disease but can be associated with serious side effects, achieving a prompt, accurate MS diagnosis is more imperative than ever. The high sensitivity of magnetic resonance (MR) imaging in depicting brain white matter and spinal cord plaques has made this technique the most important paraclinical tool in current use for the diagnosis of MS. However, many imaging abnormalities seen in MS patients are not specific to the disease. Therefore, the differential diagnosis has become a central issue. The perivenular distribution pattern and suggested increase in iron deposition of MS lesions have become targets to address this issue, particularly when susceptibility-weighted sequences are acquired on MR systems operating at high magnetic field strengths (≥3.0T). Another strategy for this purpose is to include other important aspects of MS pathology in the evaluation, such as cortical abnormalities. However, imaging of cortical lesions at standard clinical field strength remains suboptimal even when combinations of sequences are used because of limitations in the associated sensitivity and reproducibility. Despite promising findings, imaging of perivenular distribution pattern, increase in iron deposition of focal lesions, and cortical lesions at standard clinical field strength remains challenging, and substantial research efforts are needed before these features can be used in the diagnostic imaging work-up in clinical practice.

Mike Wattjes (The Netherlands)

Pediatric multiple sclerosis (MS) accounts for approximately 5% of all MS patients. MRI characteristics of childhood MS does show similarities to adult-onset MS. However, pediatric MS patient show in general fewer lesions and these lesions do show less frequently blood barrier disruption leading to contrast-enhancement. In addition, children frequently present with clinical and imaging features of acute disseminated encephalomyelitis leading to MS during later follow-up stages. In particular, patients younger than 11 years may present with atypical and larger lesions compared to those lesions seen in adult patients. The 2010 revisions of the International Panel (McDonald) criteria clearly state that adult MS diagnostic criteria may be inappropriate for certain pediatric MS patients. Therefore, neurologists and (neuro)radiologist should be aware about the differences in imaging manifestations of pediatric MS patients in order to make the correct diagnosis and to consider appropriate differential diagnosis. The aim of this lecture is to provide a comprehensive overview of conventional and advanced imaging findings in pediatric MS patients with respect to lesion differentiation of important differential diagnosis and MS lesions in adult MS patients.

Classically multiple sclerosis (MS) has been regarded as an autoimmune disease of the white matter in the central nervous system leading to severe disability over the course of several decades. Current therapeutic strategies in MS are mostly based on either immune suppression or immune modulation. Although effective in decreasing relapse frequency and severity as well as delaying disease progression, MS pathology ensues nonetheless. In the last decade it became evident that gray matter pathology plays an important role in disease progression and helps explaining certain aspects of MS-related disability such as cognitive decline. Conventional MRI outcome measures commonly used in clinical trials are sufficient to demonstrate an anti-inflammatory drug-effect but lack pathological specificity and are poor to moderate predictors of disability. Brain atrophy is a compound outcome that measures the combined effects of gray matter and white matter pathology. In this lecture I will review the prognostic relevance of brain atrophy on a group level and discuss steps needed to implement this in clinical practice. Purpose: Patients with periodic paralysis experience episodic weakness spells with intervals of normal muscle function caused by altered muscle membrane potential due to changes in ion conductivities, such as nonselective cation leaks in hypokalemic periodic paralysis and Kir2.1 mutations of the myocellular potassium (K+) channel in Andersen-Tawil syndrome. The objective was to assess whether altered sodium (Na+) and chloride (Cl-) homeostasis can be visualized in these periodic paralyses using ultrahigh field MRI. Methods: Institutional review board approval and informed consent of all participants were obtained. Nineteen 23-Na-MR (TR/TE=160/0.35) und seventeen 35-Cl-MR examinations (TR/TE=40/0.6) of both lower legs were performed on a 7-Tesla whole-body system in genetically confirmed hypokalemic periodic paralysis (Cav1.1-R1239H mutation, n=7; Cav1.1-R528H mutation, n=9) and Andersen-Tawil syndrome (n=4); median age, 47 years. Data from 16 healthy volunteers (median age, 27 years) were taken as reference. Additionally, each patient received 3-Tesla proton MR imaging on the same day using T1-weighted, short-tau inversion recovery and DIXON sequences. Muscle edema was assessed on STIR images, fatty degeneration on T1-weighted images and the muscular fat fraction was quantified using DIXON. Na+ and Cl-were quantified in the soleus muscle using three phantoms containing 10, 20, and 30 mM NaCl solution as reference.

Result: Median muscular 23-Na concentration in mmol/l was higher in Cav1. Purpose: To evaluate the functional connectivity of the visual network (VN), in patients with migraine with aura (MwA) and migraine without aura (MwoA), in the interictal period, in comparison to healthy controls (HC). Methods: Using resting-state functional MRI (RS-fMRI), the functional connectivity within VN in 20 patients with MwA was compared with 20 age-and sex-matched patients with MwoA and 20 healthy controls (HC).Furthermore, we assessed the correlation between functional connectivity within RS-VN and clinical features of patients with MwA. In addition, we used voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) to assess whether between-groups putative differences in functional connectivity were dependent on brain structural or microstructural differences. Finally, white matter hyperintensities (WMH) load of all migraine patients and HC was identified and evaluated in terms of volumetric features and signal. RS-fMRI data were analysed using the BrainVoyager QX software (voxel-level threshold p<0.05, FDR). VBM data were processed and examined using DARTEL with statistical parametric mapping (SPM8) software (p<0.05, FWE). DTI analysis was performed by using the Functional MRI of the Brain Software Library software package (p<0.05 cluster level corrected). WMH load was measured using the MIPAV software. Result: RS-fMR data showed that patients with MwA, compared to patients with MwoA and HC, had significant increased functional connectivity within VN and specifically in the right lingual gyrus (r-LG). Furthermore, we found that increased r-LG connectivity was not correlated with clinical parameters of disease severity. The abnormal VN functional connectivity was independent of structural or microstructural abnormalities as well as of WMH load. Conclusion: VN is a brain circuitry encompassing retinotopic occipital cortex and temporo-occipital regions, and representing the neural correlates of visual processing. Our findings are in line with previous electrophysiological and imaging findings suggesting a strict correlation between aura phenomenon and increased visual pathways functional connectivity in migraine. Our clinical and imaging data revealed a regional increased RS-VN functional connectivity, which is independent from structural or microstructural abnormalities, in patients with MwA. Purpose: Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an immune-mediated condition characterised by progressive or relapsing motor and sensory deficits in all four limbs. The diagnosis is based on a combination of clinical, neurophysiological and supportive criteria, but can often be challenging. Our aim was to explore the imaging characteristics of the sciatic nerves in patients with CIDP versus healthy controls using qualitative and quantitative MRI techniques. Methods: MRI of both thighs was performed at 3T in 10 patients with CIDP (7M/3F, age 52 ± 15y) and 9 healthy controls (6M/3F, age 50 ± 11y), using dual echo T2 mapping, 3D proton density (PD)-weighted, and short tau inversion recovery (STIR) sequences. T2 was measured along the length of each sciatic nerve by defining enclosing regions of interest on the T2w sequence, with the same method used to measure crosssectional area at the mid-thigh level on the PDw sequence. The nerve appearance was also evaluated qualitatively on the STIR images, and rated as isointense (0), midly hyperintense (1), or markedly hyperintense (2) compared to surrounding tissue. All measurements were performed by an observer blinded to the diagnosis. Result: Cross sectional area of the sciatic nerves was increased in patients with CIDP compared to controls (p<0.01). Median areas were 430mm2 (interquartile range 135mm2) for the CIDP group and 285mm2 (IQR 110mm2) for the control group. Median T2s were also increased in the CIDP group (60.25ms; IQR 9.9ms) compared to controls ( Purpose: We present our preliminary results achieved with the first Italian installation of a trans-cranial MRI-guided Focused Ultrasound Surgery (tcMRgFUS) certified system for functional neurosurgery. Moreover, to our knowledge, this is the world-first tcMRgFUS system ever installed on a 1.5T MRI unit. Technical issues faced to achieve a safe and effective treatment will be discussed focusing on MR high-resolution live imaging and thermometry sequences optimization.

Methods: Patient enrollment was based on indication for functional neurosurgery and evidence of medication-refractory disease; a detailed medical history has been collected together with a complete clinical examination and a neurophysiological assessment. Eligible patients have been screened by MDCT and MRI. TcMRgFUS treatments have been performed by a neurosurgeon with proven experience in functional neurosurgery, and an experienced neuroradiologist, optimizing treatment parameters case by case.

Result: Although this is a preliminary experience, the clinical success of our first treatments proves that this promising new technology for non-invasive treatment of various brain disorders can be safety and effectively performed also with the most popular MRI units operating at 1.5T. Conclusion: TcMRgFUS treatments are currently performed in a very few centers in the world and only using 3T MRI units. This is the world-first experience of functional neurosurgery successfully performed with a tcMRgFUS installed on the most popular and affordable 1.5T MR units.

Direct translational impacts are expected by the use of widely installed 1.5T MRI units both on patient quality of life and on savings in health spending, with reduction in the consumption of drugs, as well as in requests for medical examinations. Being able to use a radiation-free technique like the MRI as a guide and, even further, being able to verify the clinical effectiveness of such an innovative treatment before a permanent lesion is made in the targeted area of the brain is a huge step forward for both interventional radiology and functional neurosurgery. Purpose: To determine the diagnostic accuracy of prenatal Magnetic Resonance (MR) imaging for brain malformations in a large cohort of fetuses below 25 weeks of gestational age (GA), using postnatal MR imaging as reference standard. Methods: We retrospectively included fetuses below 25 weeks of GA, who had undergone prenatal and postnatal MR imaging of the brain from 2002 to 2014. Two senior pediatric neuroradiologists reviewed both prenatal and postnatal MR examinations in consensus. With postnatal MR imaging used as the reference standard, we calculated the overall sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV) and accuracy (AC) of prenatal MR imaging in detecting brain malformations. Result: One-hundred and nine fetuses were included in this study.

The median GA at prenatal MR imaging was 22 weeks (range: 21-25 weeks), the median child's age at postnatal MR imaging was one month (range: 0-60 months). According to the reference standard 111 brain malformations were detected: 27 midline malformations, 14 cortical gyration and cell migration disorders, 19 posterior fossa anomalies, 48 ventricular/subarachnoid space anomalies, 3 vascular malformations. The prenatal MR imaging failed to detect correctly 11 out of the 111 malformations: three midline malformations (agenesis of septum pellucidum, fused thalami, callosal hypoplasia), five cortical gyration and cell migration disorders (three polymicrogyrias and two periventricular nodular heterotopias), two posterior fossa anomalies (one molar tooth malformations and one Chiari type 1 malformation), one vascular malformation (persistent falcine sinus Purpose: Both dynamic susceptibility contrast (DSC) and dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) are widely used techniques for assessment of tumor perfusion and vascularity. In DSC-MRI, signal loss due to T2* effect of intravascular contrast material (CM) is contaminated by a signal gain due to T1 shortening by CM in interstitial space. Otherwise, T1 signal in DCE-MRI is partly influenced by T2* changes. Using a dynamic multi echo approach, temporal distribution of CM in both interstitial and capillary compartments can be assessed separately. The aim of our study was to evaluate reproducibility and diagnostic value of a dynamic-multi-echo FLASH sequence in different intracranial tumors.

Methods: 41 patients with newly diagnosed intracranial tumors (21 glioblastoma, 10 metastases and 10 meningiomas) were examined at 3 Tesla MRI prior to tumor resection, 18 of them twice (mean interval 2 days). A 10 echo FLASH sequence with a temporal resolution of 2 sec was performed after single bolus injection of gadodiamide (0.2 ml/kg body weight). Mono-exponential function was fitted to the signals of the 10 echoes in order to calculate R2* and to separate it from the T1 only dependent signal S0. Perfusion parameters were calculated with Tofts and Patlak models using different estimates for arterial input function and compared for different tumor entities. Additionally, correlation analysis of perfusion parameters in glioblastoma patients with and without Methylguanin-DNS-Methyltransferase (MGMT) promoter methylation (7 and 14 patients, respectively) was done. Result: Best reproducibility was observed for Ktrans (Tofts) derived from S0 and for cerebral blood volume (CBV), both based on AIFs derived from venous R2* time course. Meningioma showed highest values of Ktrans and CBV followed by glioblastoma. Perfusion parameters of metastases varied widely, probably due to different kinds of primary tumors. Significant differences were also found between Ktrans and CBV in glioblastoma with and without MGMT promoter methylation. Conclusion: Dynamic-multi-echo perfusion MRI combining T1 und T2* measurements after a single contrast injection allowed stable and plausible evaluation of Ktrans and CBV in different intracranial tumors. In addition, our preliminary data suggest significant differences in perfusion patterns of glioblastoma dependent on their MGMT promoter status. Purpose: Among patients with frontotemporal dementia (FTD), psychiatric symptoms are frequent. One hypothesis is that this is caused by impaired insular function (Sliz, Front Hum Neurosc, 2012). We studied whether regional perfusion in the insular cortex is lower in FTD than controls, taking grey matter (GM) atrophy into account. Methods: Thirty-seven FTD patients and 34 controls underwent 3T MRI, including 3D high-resolution (1mm3) T1w and 3D pseudocontinuous arterial spin labeling. GM volume and cerebral blood flow (CBF in ml/ min/100g), corrected for partial volume effects, were quantified for whole supratentorial brain and insular cortex, left and right separately. Total brain and insular CBF and GM volume were compared between patients and controls, adjusted for age, sex, and intracranial and GM volumes for CBF, using linear regression.

Result: There was no significant difference in age between FTD patients (63y) and controls (62y; p=0.36) or in gender (52% males; p=0.19). Total brain GM was on average 62.6 ml lower in FTD patients than controls (p<0.001, 95% confidence interval [CI] -81.8 to -43.5). This difference was also present in the insula, more pronounced left than right (difference: left -1.2 ml/min/100 ml, p<0.001, 95% CI -1.6 to -0.7; right -0.7 (95% CI -1.2 to -0.3; p=0.003). Total brain CBF was 7.2ml/min/100g lower in FTD patients than controls (p<0.001, 95% CI -11.5 to -3.0). This difference however attenuated after adjustment for total GM volume to -4.2 ml/min/100g and lost significance (p=0.12). Insular perfusion was significantly lower in patients than controls, more pronounced on the left than right (difference: left -9.5 ml/min/100g, 95% CI -13.7 to -5.3, p< 0.001; right -7.4, 95% CI -11.7 to -2.9, p=0.005). This difference persisted even after adjustment for insular GM atrophy (difference: left -8.8, 95% CI -13.6 to -4.0, p=0.001; right -6.4, 95% CI -11.1 to -1.8, p=0.008).

Conclusion: FTD patients showed pronounced hypoperfusion in the insula, even when accounting for regional atrophy. Our further research focuses at assessing whether such insular hypoperfusion relates to the burden of psychiatric symptoms in these patients, results which we aim to also present at the meeting. Purpose: The present study shows the results of a double-blind shamcontrolled pilot trial to test whether measurable stimulus-specific RSFC changes exist after plantar mechanical stimulation in patients with idiopathic Parkinson Disease. Methods: Eleven patients (6 women and 5 men) with idiopathic Parkinson Disease underwent brain fMRI immediately before and after sham or effective plantar mechanical stimulation. Resting state Functional Connectivity (RSFC) was assessed using the seed-ROI based analysis. Seed ROIs were positioned on basal ganglia, on primary sensory-motor cortices, on the supplementary motor areas and on the cerebellum. Individual differences for pre-and post-effective plantar mechanical stimulation and pre-and post-sham condition were obtained and first entered in respective one-sample t-test analyses, to evaluate the mean effect of condition. Result: Effective plantar mechanical stimulation, but not sham stimulation, induced increase of RSFC of the sensory motor cortex, supplementary motor area, nucleus striatum and cerebellum. Secondly, individual differences for both conditions were entered into paired group t-test analysis to rule out sub-threshold effects of sham plantar mechanical stimulation, which showed stronger connectivity of the primary sensory-motor cortex with the post-and pre-central gyrus (max Z score 3.50) and of the cerebellum with the left lateral occipital cortex, precuneus and left cerebellar paravermal cortex (max Z score 3.64). Conclusion: Our results suggest that effective plantar mechanical stimulation acutely increases RSFC of brain regions involved in visuo-spatial and sensory-motor integration. Clinical Trials. Purpose: Cortico-basal syndrome (CBS) is an atypical parkinsonism characterized with cortical and basal ganglia neurodegeneration. Our aim was to evaluate possible specific changes in cortical thickness (CTh) and anatomically constrained tractography in CBS patients compared to healthy subjects (HS). Methods: We recruited 11 CBS patients and 11 age-and gender-matched HS. Motor signs were scored with the Unified Parkinson's Disease Rating Scale (UPDRS). Patients were divided in two groups on the basis of clinical asymmetry: left (l-CBS) and right (r-CBS). Diffusion tensor imaging (DTI) and 3D-T1 images were acquired with a 3T MRI scanner. Data analysis was performed using Freesurfer software. 3D-T1 images were segmented on the basis of Desikan/Killinay atlas to obtain 34 cortical regions to calculate the CTh. Volumes of seven subcortical structures (thalamus, caudate, accumbence, pallidum, putamen, hippocampus and amygdala) in each hemisphere, brainstem and corpus callosum were also extracted.

Streamline tracts were reconstructed in individual diffusion space using the Tracts Constrained by Underlying Anatomy (TRACULA) toolbox. Average and voxel-wise fractional anisotropy, axial diffusivity, median diffusivity and radial diffusivity values were calculated within eight major WM tracts in each hemisphere (corticospinal and anterior thalamic tracts, uncinate, superior and inferior longitudinal fasciculi, cingulum bundle, genu and splenium of corpus callosum). Result: Patients had significant CTh reduction in the precentral and superior temporal gyri, bilaterally. Analysing l-CBS and r-CBS separately, the CTh was found decreased preferentially in the cerebral hemisphere contralateral to the clinically more affected body side. Patients also showed significant volume loss in the putamen, hippocampus, accumbence bilaterally, in the corpus callosum and right amygdala. In patients, DTI values were altered in all WM tracts, without significant asymmetries. The CTh reduction in the rolandic area significantly negatively correlated with both the contralateral limb UPDRS scores and disease duration. Conclusion: Our results show a circumscribed and asymmetric cortical thinning, which correlates with clinical severity and disease duration in patients with CBS, and likely represents the anatomical substrate of clinical impairment in the disease. Thierry Huisman (USA)

The pediatric spinal canal and its contents are a significant diagnostic challenge. The small cross sectional size of the spinal cord, the prominent cerebrospinal fluid pulsation artifacts, the significant cardiac pulsations and higher respiration rate may negatively influence advanced neuroimaging techniques. Diffusion weighted imaging and diffusion tensor imaging have become a powerful diagnostic tool in the diagnostic work up of a large variety of neurological diseases of the pediatric brain. Translating these sequences to the spinal cord is not straightforward and require dedicated hard and software solutions. In the current presentation we will discuss the current advances in anatomical and functional imaging of the spinal canal and cord using a case based approach. Next to diffusion weighted and diffusion tensor imaging we will also explore magnetic resonance imaging, susceptibility weighted imaging and functional MRI.

This lecture on fetal spine and spinal cord will focus on the imaging techniques complementary to ultrasound that consist of CT and MRI. Neuroimaging is discussed mostly in the context of malformations which is the major indication.

Learning objectives: To identify the neuroradiological appearance of spinal dysraphisms, to correlate such features with a corresponding embryologic derangement, and to be able to use a clinicalneuroradiological classification scheme in the everyday clinical practice. Embryology and classification: Spinal cord development occurs through three consecutive periods: (i) gastrulation (2nd gestational week): the embryonic disk is converted from a bilaminar into a trilaminar arrangement, with formation of the intervening mesoderm; the notochord is laid down along the midline, identifying the craniocaudal embryonic axis; (ii) primary neurulation (18th-27th day): under the induction of the notochord, the midline ectoderm specializes into neural ectoderm. The initially flat neural plate progressively bends and folds until it fuses in the midline to form the neural tube. The primary neural tube produces the uppermost 9/10 of spinal cord; (iii) secondary neurulation (28th-48th day): a secondary neural tube is laid down caudad to the termination of the primary neural tube. Retrogressive differentiation of the secondary neural tube results in the tip of the conus medullaris and filum terminale. Defects in one of these three embryological steps produce spinal dysraphisms, characterized by anomalous differentiation and fusion of dorsal midline structures. Spinal dysraphisms may be categorized clinically in two subsets: open and closed spinal dysraphisms.

In open spinal dysraphisms (OSD) the placode (non-neurulated neural tissue) is exposed to the environment through a cutaneous defect along the child's back. OSD include myelomeningocele, myelocele, hemimyelomeningocele and hemimyelocele, and are associated with a Chiari II malformation. Myelomeningocele is by far the most common of these forms; the placode protrudes through a posterior defect and is elevated above the skin surface due to concurrent dilatation of the subarachnoid spaces. Closed spinal dysraphisms: Closed spinal dysraphisms (CSD) are covered by intact skin, although cutaneous stigmata usually indicate their presence. Two subsets may be identified based on whether a subcutaneous mass is present. CSD with tumefaction comprise lipomas with dural defect (lipomyelocele and lipomyelomeningocele), meningocele, and myelocystocele. Lipomas with dural defect are more common; they are differentiated from one another based on the position of the cord-lipoma interface, that lies within the spinal canal in lipomyelocele, and outside the spinal canal (ie, into a meningocele) in lipomyelomeningocele. CSD without tumefaction comprise complex dysraphic states (ranging from complete dorsal enteric fistula to neurenteric cysts, diastematomyelia, dermal sinuses, caudal agenesis, and spinal segmental dysgenesis), bony spina bifida, tight filum terminale, filar and intradural lipomas, and persisting terminal ventricle. The most complicated forms (complex dysraphic states), including diastematomyelia, caudal regression, and segmental spinal dysgenesis) are related to faulty gastrulation. Diastematomyelia (literally, split cord) is caused by failure of midline notochordal integration, resulting into two separate hemineural plates. Caudal agenesis and segmental spinal dysgenesis are related to defective notochordal formation, characterized by absence or hypoplasia of a segment of the notochord, in turn resulting into absence or hypoplasia of a corresponding segment of the spinal cord.

Aims: In this presentation a systemic MRI pattern recognition of hyperintense signal intensity in the spinal cord will be presented. The differential diagnosis of these lesions will be discussed. Clinical cases will be presented and discussed. Introduction: A case based review of the various pathologies of the spinal cord will be reviewed. We will learn the typical signal abnormalitirs of each pathology. The presentation will be built with cases, discussion on the clinical information, age of onset, the radiological presentation, the differential diagnosis and the treatment offered. Mri parameters are: location, extension, T1 presentation, GAD enhancement and follow up.

The pathologies that will be shown are inflammatory, vascular, infections, tumoral and metabolic. Including diseases and syndromes of: neuromyelitis optica, multiple sclerosis, intra axial spinal tumors, arterio-venous fistula, vitamines deficiency and more. By the end of the presentation the differential diagnosis and the corect diagnostic approach to the correct diagnosis will be clear.

Thierry Huisman (USA)

Pediatric neuroraiologists andgeneral neuroradiologist should be familiar with the normal and abnormal developmental anatomy of the pediatric central nervous system as well as child and age specific pediatric diseases. In addition, depending on the age various imaging modalities may have different strengths and limitations. In the current presentation we will discuss common pitfalls, variants and non-pathological neuroimaging findings that may mimic true pathology.

8:00-13.00 Up to date on Aneurysm Treatment and DAVF S10.3 GIANT ANEURYSM: EVT

Large and giant intracranial aneurysms pose an increased risk due to a high incidence of rupture and resultant neurological deficits caused by compression of neighboring neural structures. Successful treatment of such aneurysms is hampered by high surgical morbidity and low efficacy of coil embolization due to a high rate of incomplete occlusion and recurrence. Parent artery occlusion is effective and remains the gold standard, but is restricted to aneurysms with sufficient collateral circulation. Flow modification techniques and newer neck remodeling methods have been recently introduced to overcome these difficulties. For side wall aneurysms, flow diversion (FD) using high mesh density woven FD devices has been proved highly effective in permanently eliminating mass effect. Due to the relative high incidence of delayed rupture (4.5%), additional coil packing is recommended for very large and giant aneurysms. For bifurcation aneurysms, FD is restricted to highly asymmetrical configurations. In true bifurcation aneurysms, stent assisted coil embolization, Y stent reconstruction and other neck remodeling techniques ("waffle cone", "barrel" stent, intra-arterial neck protection device) can be used in combination with intrasaccular coil packing. Stent assisted embolization provides some improvement of the long term results, but recurrence remains a common problem. The newer neck protection techniques make endovascular treatment feasible in most cases, however, their long term effect is not yet proved. Parent artery occlusion with or without bypass surgery still needs to be considered as a potential option for such aneurysms.

Bart van der Zwan (The Netherlands)

Giant intracranial aneurysms have a grave natural history and still are a major challenge for neurosurgeons and radiologists. Although endovascular techniques are improved yearly, there still remains a significant portion of these aneurysms that is not treatable with surgical or endovascular means. Both high-flow as low-flow bypass surgery or combinations can be powerfull tools in replacing the aneurysm bearing arteries in case vessel sacrifice is not safe. Although conventional bypassing using temporal clipping of the recipient vessel can be a succesfull treatment of more distally located aneurysms, for bypassing arteries with larger territories this conventional technique bears increasing risks due to its occlusive character. To circumvent this hazard the Excimer Laser Assisted Non-occlusive Anastomosis technique (ELANA) has been developed in our department. ELANA enables the neurosurgeon to construct an end-to-side anastomosis without temporal occluding the recipient artery and thus safely creating high-flow replacement EC-IC or IC-IC bypasses on proximal cerebral arteries in the treatment of giant ICA aneurysms. Pre-and intraoperative flowmeasurements are mandatory in planning and performing this type of surgery. Until present ELANA has been performed on >450 patients and is now available in 6 centers in Europe and in 5 centers in the US and Canada. The innovative ELANA bypass technique prooves to be an efficient and save treatment modality in the the cohort of difficult to treat patients with giant aneurysms and is a powerfull tool also in combination with conventional bypass techniques.

Introduction: Intacranial Dural Arterio-venous fistulas (ICDAVFs) may be revealed by a wide variety of symptoms. The symptomatology and neurological risk depend on the DAVF location and venous drainage. The treatment strategy must be adapted to the arterial and venous angio-architecture. The goal and type of treatment have to be adapted to the venous drainage type and consequent treatment neurological risk. Treatment indications: Depending on patient age, symptoms and neurological risk the therapeutic strategy usually consists in: -Type I/IIa: No treatment, -Arterial Onyx/Phill injection with sinus balloon protection -Type IIb: Sinus occlusion by either: -arterial approach and Onyx/Phill injection, -venous approach and coïls placement or Onyx/Phill injection -Type II/IV/V: -Arterial approach and Onyx/Phill injection Conclusion: Endovascular treatment allows occlusion of almost all ICDAVFs. Treatment strategy and approach must be decided individually according to patient risk and DAVF venous drainage.

Until 1999, n-butyl cyanoacrylate (NBCA) had been the the only embolizing agent for the endovascular brain AVM treatment offering limited penetration of the nidus. Selection bias had been very important factor at those times effecting the success of embolization using glue. After implication of Onyx in our practice in 1999, we developed in Ankara an intranidal Onyx injection technique allowing us to penetrate the AVM nidus far better. This technique gained worldwide acceptance and it became possible to obtain either a cure in much higher rate or create significant reduction in the size of the large high grade AVMs to make them treatable with radiosurgery or surgery. New philosophy of this approach has been as radical as microsurgery targeting cure of the brain of AVM.

However, ARUBA trial results created a certain paradigm shift in brain AVM management although many criticize the trial design. This shift pushed endovascular operators to improve treatment results with alternative techniques/approaches augmenting the intranidal occlusion.Herein this presentation, these new approaches like simultaneous intranidal multiple microcatheter injections and transvenous intranidal occlusion will be discussed with their indications.

Although not so frequent, Dural Vascular Malformations nonetheless present a complex spectrum of neurological pictures. Those symptoms are generally related to either blood flow through AV shunts ( such as tinnitus) or venous ischemia of neural tissue due to venous hypertension. In most of the cases Endovascular treatment is the treatment of choice because of effectiveness and safety. Certain precautions are needed for a safer and more effective treatment. The most important step in treatment planning is the analysis of the malformation. The feeders, the fistulae site and the venous drainage should be thoroughly scrutinized. Venous drainage is probably the most important elements since most of the major sometimes-fatal complications are related to the venous site. Draining venous structures either pial veins or dural sinuses are to be separated as dedicated (draining fistula only) or shared (draining normal tissue as well). All shared venous structures need to be spared while dedicated ones can be safely occluded. Once venous site is decided the either trans arterial or trans venous routes can easily be chosen and the embolic agent ( coils, liquids etc) will also be decided accordingly. While performing trans arterial liquid embolization so called dangerous anastomosis should be kept in mind in order to prevent inadvertent occlusion of normal branches feeding either neural tissue or cranial nerves.

Neuroradiology and in particular Interventional Neuroradiology can expose patient and staff to considerable amounts of ionizing radiation. A patient may be subjected to many treatments and diagnostic procedures, including angiography, CT, CT angiography and perfusion, with considerable accumulated radiation dose, This may be cancerogenic or cause eye cataract. In addition there are short term effects such as alopecia or skin burns. The effects depend on the amount of radiation absorbed in the tissue, the organ irradiated and the patient age. Children are more sensitive and have longer expected life span and may thus develop tumors later in life. Staff are rarely subject to direct radiation but can be exposed to very high accumulated doses of radiation. Eye cataract is not uncommon in physicians engaged in X-ray guided procedures. The guidelines for eye exposure in professionals have therefore recently been revised. We will look into recent data on radiation doses to patient and staff and how to minimize this patient and occupational hazard. Technical aspects such as collimation, image rate, different reconstruction algorithms, the effect of C-arm angulation etc will be discussed.

Naci Kocer (Turkey)

Minimal invasive surgery has gained enormous acceleration of acceptance in every section of surgical medicine in last 20 years. Interventional neuroradiology is luckily has access to this evolution especially in endovascular treatment techniques of neurovascular disorders. As it appears in all new surgical techniques, to get scientific proof and high level of evidence need some times and big effort. Accumulation of knowledge and having negative or positive or neutral data shapes societies to select certain treatment options for their cases. In the lecture ,RCT effects on endovascular treatment strategies will be discussed. Purpose: Purpose:Trial outcome measures in neuromuscular diseases such as Duchenne muscular dystrophy (DMD) currently rely on invasive or functional but insensitive tests. Muscle MRI could offer a valuable alternative. Reliable evaluation of the upper limb could permit inclusion of non-ambulant DMD individuals not able to perform functional tests such as the 6-minute walk test. We aimed to compare longitudinal MRI-quantification of fatinfiltration in the forearm muscles of non-ambulant DMD patients and healthy controls. Methods: Methods: 16 DMD boys and 10 age gender and age matched controls were included in this on-going study. Fat-water quantification was used to compare fat-infiltration in the forearm muscles of non-ambulant DMD patients and healthy controls. DMD individuals underwent 3T 3-point Dixon imaging of the dominant forearm to measure muscle fat-fraction (f.f.). Ten forearm muscles were segmented and mean f.f. and cross-sectional area recorded. Patients also underwent physiotherapy evaluation: Performance of Upper Limb (PUL) module; wrist extension myometry; and EK2 performance of tasks in daily life interview. Time to loss of ambulation (LOA) was recorded. Result: Results: To date, 7 non-ambulant DMD patients (mean age: 13.6 years; mean duration of non-ambulation 23.6 months) have been examined at baseline and 6 months, and 5 have returned for 1yr follow-up. 10 controls (mean age: 14.6 years) have also been imaged. At baseline overall mean f.f (±SD) in DMD was significantly higher than healthy controls: (13.4±11%vs 0.7±0.1%, p=0.002). Total mean area was reduced in DMD (1735±331mm2) compared to healthy controls (2398±821mm2, p=0.04). Overall f.f. correlated with LOA (Spearman r=0.8, p=0.02) and wrist extension myometry (r=0.8, p=0.004) and less strongly with PUL (r=-0.6, p=0.09) and with EK2 (r= 0.6, p=0.09). In patients mean f.f. difference at 6 months was 4% (95%CI 0.9, 7.1); p=0.01. Mean difference from baseline in the 5 patient-subject analysed at 12 months was 5.5% (95%CI 0.8, 11.5). Our final analysis will include additional distal and proximal imaging slices. Purpose: Recent post-mortem studies showed millimetric focal anomalies distributed throughout the cerebral cortex in autism spectrum disorder (ASD). To date, classic parametric voxel-based morphometry (VBM) was not able to detect diffuse focal cortical alterations in ASD. The present study aims to detect structural anomalies in the under-researched condition of LFASD by threshold-free cluster enhancement (TFCE) voxel-wise investigation. Methods: Twenty-five idiopathic LFASD (22M-3F, 6.11±3.10ys), 25 typically developing (TD, 12M-13F, 6.11±2.6ys), and 25 nonsyndromic intellectually disable (ID) children (16M-9F, 7.0±3.1ys) were enrolled. DARTEL normalization to a study-specific template, segmentation, non-linear only modulation and several smoothing kernels were applied. 2mm/4mm/8mm smoothed images were used in the classic parametric VBM and 0mm/2mm/ 4mm smoothed images were used in the TFCE-based non parametric VBM. Local gray matter (GM)/white matter (WM) volume differences were investigated using one-way ANOVAs (nuisance covariates: age, gender, IQ, total GM/WM volume) designed in SPM8.

Result: Regardless to the smoothing kernel applied, classic VBM (p<0.05 FWE corr) was not sensitive to differences among the groups. TFCE tests were sensitive to local GM and local WM volume differences (p<0.05 FWE corr). The larger smoothing kernel was applied, the more diffuse the differences were. Local GM volume was significantly different between LFASD and both TD and ID in a fronto-cingulate-parietal pattern. In addition, body and genu of corpus callosum showed decreased local WM volume in LFASD and basal ganglia alterations were found in both LFASD and ID. Conclusion: Unlike classic parametric inference, non parametric inference allowed to highlight diffuse focal cortical alterations in LFASD. For the first time, diffuse focal cortical alterations are shown in LFASD by MRI-based investigation. Structural anomalies in fronto-cingulate-parietal regions might be specific to ASD. Alterations might indeed reflect the patches of disorganization in the neocortex, subtle focal cortical dysplasias most abundant within the prefrontal lobes described and associated to focal and distributed thinning of the cortex by post-mortem investigations. Thus, voxelwise MRI-based investigations may be sensitive to such structural anomalies and the focal nature of the expected cortical anomalies ought to be taken into account in further MRI-based investigations in ASD.

Autism spectrum disorder,cortical abnormalities,voxel-based morphometry Purpose: progressive supranuclear palsy (PSP) is a late-onset neurodegenerative disorder characterized by motor and cognitive deficits. Previous structural imaging studies have revealed supra-and infratentorial white matter (WM) changes]. However, conflicting clinical radiological correlations have been reported. The aim of the present study was to explore WM changes in patients with PSP and their potential associations with clinical and cognitive parameters Methods: By using 3-Tesla magnetic resonance imaging and tract based spatial statistic (TBSS) analysis we compared WM volume in 18 patients with clinically probable diagnosis of PSP and 18 healthy controls (Hcs). Fractional anisotropy (FA), axial (AD), radial (RD), and mean diffusivity (MD) maps were generated. All patients and Hcs underwent a clinical and neuropsychological evaluation. TBSS analysis was performed by using the functional MRI of the brain (FMRIB) software library (FSL) software package. In the between group analysis we compared the FA, MD, AD, and RD maps of all patients with PSP with HCs. Wholebrain correlations were calculated, using general linear model tool of FSL package, to evaluate the relationship between DTI parameters (FA, AD, RD, and MD) and clinical and cognitive scores. Statistical threshold was set at p < 0.05. Group differences were assessed with age, sex, and years of education as covariates. All analyses were re-run with the inclusion of WM hyperintensity volume as an additional covariate. Result: Patients with PSP compared with HCs, showed an abnormal diffusivity involving corpus callosum, right fornix, midbrain, inferior fronto-occipital fasciculus, anterior thalamic radiation, superior cerebellar peduncle, superior longitudinal fasciculus, uncinate fasciculus, cingulate gyrus and cortico-spinal tract bilaterally. Among the significant clinical-radiological correlations and in line with our previous voxel-based morphometry findings, we detected an association between motor and cognitive dysfunction with fronto-cerebellar WM involvement. Conclusion: Our results confirmed the well-known role of cerebellar pathology in the pathogenesis of motor impairment in patients with PSP and may suggest that beyond an "intrinsic" frontal cortical involvement, an "extrinsic" frontal lobe dysfunction may underlie cognitive deficits in this devasting disorder. Purpose: Potential neuroanatomical changes resulting from blindness have remained largely unexplored. Recently, an involvement of amygdala, a subcortical structure not primarily engaged in visual processing, has been suggested by multisensorial functional imaging in congenital blindness. Aim of this study is to evaluate volumetric changes and white matter connections of amygdalae by Magnetic Resonance Imaging, relating different findings to clinical and behavioural tests. Methods: We acquired high-resolution T1-weighted and DTI MRI scans in 12 congenitally blind (mean age 42 ± 13 years) and 15 sighted control (mean age 46 ± 13 years) subjects. FreeSurfer was used to segment the amygdala bilaterally, and volumes were extracted for group and gender comparisons. Following, amygdala connections with whole brain were analyzed in both the groups, using FreeSurfer segmented volumes as seeds for probabilistic tractography. Finally, findings were correlated to age of disease and Braille reading performances (words per minute) for the congenital blind subjects. Result: A significant reduction of amygdala volumes has been detected in congenital blind subjects, compared to sighted controls. This atrophy is correlated to age of disease but not to the age of control subjects or Braille performances. Four tracts have been detected using as seed the parcellated volume of amygdalae extracted by FreeSurfer: the uncinate fascicle, the anterior commissure, the fornix crux and the inferior longitudinal fascicle. A selective alteration of inferior longitudinal fascicle, in terms of reduced fractional anisotropy, increased radial diffusivity, and reduced tract volume has been detected for congenital blind subjects, compared to controls. No significant alterations resulted for the remaining white matter tracts. Conclusion: Congenital blindness determines a volumetric reduction of amygdala that is related to an alteration of Inferior Longitudinal Fascicle integrity, probably due to visual deafferentation, with a preservation of other amygdala fascicles. These changes are correlated to age of disease but not Braille reading performances, and contribute to brain neuroplasticity of congenital blind subjects. Purpose: Diagnostic decision-making process in disorders of consciousness is extremely subjective. Diagnostic methods offer minimal resources for objective functional research. Resting function magnetic resonance imaging (rFMRI) allows to estimate the neural networks activation, connectivity and its interactions in the brain with the present or absent evidence of consciousness. According to the literature, patients with severe brain damage, who survived coma, by increasing the consciousness level, show selective activation of the default mode network (DMN). The aim of our study was to evaluate the parameters of the DMN activation in clinical cases of patients with chronic disorders of consciousnessunresponsive wakefullness syndrome (vegetative state -VS) and minimal consciousness state (MCS). Methods: We included 4 patients with disorders of consciousness with various etiology -1 person with anoxic brain injury,1 with severe traumatic brain injury both after one year period, 1 with hemorrhagic stroke with 3 months after injury and 1 with acute disseminated encephalomyelitis 3 months after onset. Control group included 3 healthy volunteers. Level of consciousness was assessed with the well-established standardized Coma Recovery Scale-Revised (CSR-R) behavioral test and on admission the results showed 4,12,18 and 18 points, which complies with VS in the first case and MCS in three left. Result: DMN activity was not detected in the 'unresponsible wakefullness syndrome' case. Though, in MCS, we found a significant activity increasing in DMN structures. Statistically significant index of functional connectivity between the right and left parahippocampal gyri in patients with MCS was 3.46 (N=20.13); between the left front cingulate gyrus and sulcus intraparietal was -6.28 (normal data functional connectivity in structures is absent The vetting, protocolling and prioritisation of imaging requests forms a fundamental part of the Neuroradiologist's role, yet is rarely formally taught nor assessed. The purpose of this project is to develop a radiology-specific WPB assessment (VetPro) which focuses training on this vital but neglected area, and to test its feasibility and educational validity. Methods: Based on a systematic literature review and curriculum competencies, key domains were identified and refined using a Delphi study; an iterative consensus technique with controlled feedback from an expert group. Result: Radiologists from 5 teaching institutions were contacted, and following a 36% response rate (44 consultants), a 3-round Delphi study was undertaken. Each facet was rated on a 1-5 Likert scale. This led to the refinement of a prototype assessment tool consisting of the 14 highestranked domains (Vetting -radiology protection, clinical interpretation/ Protocolling -understanding of image modalities and sequences, communication/ Prioritisationjudgement, insight and decisionmaking) as well as a global ranking score. The format was derived from validated WPBAs, including the mini-CEX, utilising a 6-point ordinal scale, each anchor relating to the degree of competency expected for the stage of training, and one global summary score using a 4 point scale, with anchors linked to readiness for independent practice. 10 assessors comprising 7 neuroradiologists and 3 radiographers from 4 neuroradiology centres are concluding assessments on a cohort of 30 trainees, specifically addressing statistical differences in global rating scale between trainees with differing levels of training and experience. Reliability coefficients will dictate the number of assessors and assessments needed to reach acceptable levels of reliability for summative assessments. Conclusion: To prepare trainees for their future consultant role, the development of the VetPro WPBA provides a radiology-specific assessment tool which targets the often overlooked competencies necessary for imaging request vetting, protocolling and prioritisation. This novel assessment, which is being integrated into clinical practice, emphasises relevant and focused feedback which improves engagement in the educational process. Here we report serial changes of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) in a sCJD case with long lasting course.

Methods: A 79 years-old woman presented with mild limb ataxia, postural instability and initial impairment of executive and memory functions. In the following 9 months, we observed a rapidly progressive cognitive deterioration, with aphasia, apraxia, visuo-spatial impairment and severe amnesia. In the last 4 months, motor impairment became severe, with unsteadiness of gait and diffuse bradykinesia. At the time of the abstract submission, the patient is alive, bedridden, with severe rigidity of limbs and trunk, myoclonic tremor and akinetic mutism.

Six MRI scans were acquired by a Siemens Skyra 3T scanner, 4, 6, 7, 9, 11 , and 13 months after symptoms onset. FLAIR and DWI were acquired in every scan but the last one, with significant motion artifacts even in repeated DWIs. In each scan, ADC was longitudinally measured by circular ROIs positioned on the same locations in frontal, temporal cortex and putamen, of both hemispheres.

Result: Visual inspection of DWI revealed diffuse cortical ribboning since the first scan, with posterior prevalence and left hemispheric dominance (figure). This cortical ribboning without striatal involvement appeared stable until 11 months after symptoms onset, when a subtle hyperintensity of left external putamen was observed. A bilateral striatal involvement with pathognomonic anterior-posterior gradient appeared only in the last scan, 13 months after symptom onset, togehter with spreading of cortical ribboning . The ADC measurement better evaluates the observed diffusion changes: stability in the selected cortical regions, and progressive diffusion restriction in the putamina. Conclusion: Serial MRI with DWI-ADC can track the cortico-subcortical spreading of prion disease in sCJD.

In cases with isolated cortical ribboning, striatal involvement can occur very late in the disease's course. 1. How to prepare your manuscript so as to identify the right audience, the right journal and what distinguishes an excellent article from a poor one. 2. How to structure a research article with regard to form, authorship, a catchy title and key words. 3. How to identify do's and do not s with regard to ethics, illustrations and plagiarism. 4. What to anticipate from and how to use the peer review process to your advantage. 5. Checklist for accepting the Nobel Prize.

The purpose of publishing a scientific article is to provide a document that contains sufficient information to enable the reader to evaluate the comments you made, to repeat the experiment if desired, and to judge whether the conclusions are justified by data. This brief summary aims to give suitable tools for a right preparation of the medical work. The scientific paper must be structured according to rules established and presented in the best possible way. To redact correctly the paper that you're going to present for publication, you must follow precise editorial guidelines. Before starting the first draft, you should read the instructions for authors provided by each journal and prepare the work according to these. This is to avoid that journal's editors evaluate your work inappropriate, regardless of the quality of scientific content. Several journals give very detailed instructions annually and these ones can be very useful to learn some basic rules. Basic Structure (IMRAD) The basic structure of a scientific paper is summarized in the acronym IMRAD, which means:

•Introduction (what questions were asked?)

•Methods (how these questions have been studied?)

•Results (what was found?) •And •Discussion (What do results mean?)

RCTs are considered as offering the highest level of evidence base medicine but unfortunately most are designed to measure the primary effects of a treatment and not the performance of diagnostic studies. Diagnostic imaging studies are generally of lower evidence base medicine levels (3 or 4). The structure of most RCT includes: the participants, allocations, intervention, and measurements of outcomes as per statistical analysis. Randomization and thus group allocation is their most important component and need to be completely free of bias. For purpose of this lecture we will analyze 3 RCTs: a clinical one (the use of antibiotics in sinusitis) and two imaging ones (MR. CLEAN and the original ISAT studies). The last one will serve as an example as to the utility of interim data analysis and early termination of a study.

Learning how to review papers not only makes a better reviewer, but it can also help an author, since an understanding of the process can help to write paper submissions for an audience of reviewers. The knwoledge of the criteria of the reviewer will use to judge the paper, to positioning it in a much better position to tailor the paper so that it has a higher chance of being accepted. Peer review helps validate research, establish a method by which it can be evaluated, and increase networking possibilities within research communities. Despite criticisms, peer review is still the only widely accepted method for research validation.Three type of peer review will describe. Single Blind Review The names of the reviewers are hidden from the author. This is the traditional method of reviewing and is the most common type by far. Reviewer anonymity allows for impartial decisions ; the reviewers will not be influenced by the authors. Double Blind Review: both the reviewer and the author are anonymous. Author anonymity prevents any reviewer bias, for example based on an author's country of origin or previous controversial work. Open Review: Reviewer and author are known to each other. Reviewing is both a privilege and responsibility. It takes time to prepare a useful, critical review. Moreover, it clearly is a service to the journal, to the authors, to science at large, and to the reviewer because the reviewer becomes privy to the latest in cutting-edge research. Purpose: Low grade gemistocytic astrocytoma (GemA) has shown characteristic features which are different from other low grade astrocytoma and mimicking high grade glioma. The purpose of our study was to evaluate the clinical and radiologic findings of low grade GemA and to compare these findings with those of low grade non-GemA. Methods: MR imagings were obtained in 18 patients with pathologically confirmed as low grade GemA between January 2005 and December 2014 and 18 patients with pathologically confirmed as low grade non-GemA between January 2009 and December 2011 in single institution. Demographic data, conventional and advanced MR imaging findings, and follow-up results of both low grade GemA and low grade non-GemA were evaluated.

Result: The incidence of tumor necrosis and enhancing tumor portion were significantly different between the low grade GemA and low grade non-GemA (P = 0.002 and P = 0.005, respectively). Findings of diffusion restriction and increased relative cerebral blood volume (rCBV) value were more frequently observed in the low grade GemA than low grade non-GemA without statistical significance. Cho/Cr and Cho/NAA ratio of low grade GemA were higher than low grade non-GemA without statistical significance. High grade transformation or tumor progression were suspected in 13 (76.5%) of 17 patients with low grade GemA and 6 (33.3%) of 18 patients with low grade non-GemA during follow-up periods. 5-year progression-free survival (PFS) of low GemA was worse than that of low grade non-GemA (21.4% and 59.3%, respectively, P =0.049).

Conclusion: Low grade GemA could present with MR imaging findings mimicking high grade glioma and showed shorter PFS than low grade non-GemA. Keywords Glioma,gemistocytic astrocytoma,GemA This study aimed at assessing the potential role of DIR in delineating low grade glioma (LGG) in comparison to fluid-attenuated inversion-recovery (FLAIR) and T2-weighted turbo-spin-echo (T2w-TSE) by determining confidence in defining the tumour borders and differences in tumour volumes. Methods: 3D DIR, FLAIR, and T2w-TSE sequences were acquired on a 3T scanner (Siemens, Erlangen) in 6 subjects with presumed LGG. Three raters assessed the tumour boundaries and volume (iPlan2.7 BrainLAB, Feldkirchen) for each sequence, in consensus, at 2 different time points (different days). Their confidence was recorded with a 3-points scale (0=low, 1=medium, 2=high). Fractional volumetric changes between the two time points (intra-rater reproducibility) and of T2w-TSE and FLAIR versus DIR were assessed with onesample t-tests.

Result: In all cases the greatest confidence in tumour delineation was with DIR (mean(sd)=1.8(0.4)), followed by FLAIR (mean(sd)=0.8(0.4)) and T2w-TSE images (mean(sd)=0.0(0.0)). The percent difference between the two time points was not statistically significant (p=0.39, 0.81 and 0.15 for T2w-TSE, FLAIR and DIR respectively), and the average of the modulus of the percent difference between the two time points were of the same order of magnitude (11.2%, 7.5% and 6.5% for T2w-TSE, FLAIR and DIR respectively), reflecting a high intra-rater reproducibility and suggesting learning in tumour segmentation on DIR.

The mean(sd) percent difference between volumes measured on T2w-TSE and DIR was +7%(14%) (p=0.15) and between FLAIR and DIR was +1.3%(6.0%) (p=0.31). To further substantiate these findings a sample size of 45 subjects would be required for a significance level of 5% with 90% power. Conclusion: For preoperative LGG segmentation, DIR provides the highest observer confidence whilst the resulting volumetric assessment is comparable to the FLAIR rather than the T2w-TSE conventional sequence. To detect a statistically significant difference between DIR and FLAIR the sample size will need to be increased to at least 45 subjects. In addition to a faster segmentation, the increased DIR contrast could facilitate automated methods enabling routine volumetric tumour measurements, which may increase diagnostic accuracy when monitoring disease progression. Result: Human GBM cells formed intracerebral masses 5~7 days after stereotactic implantation in all animals ( Figure 1 ). Dynamic enhancement patterns after contrast media injection were different according to the property of contrast media (Figure 2 ). At the DCE curves of the brain tumor model, the signal enhancement for ionic agents was prolonged over 80 minutes while that for nonionic agents was less than 30 minutes. Conclusion: Ionic MR contrast agents remained longer than nonionic agents in the rodent brain tumor. Thus nonionic agents may be a better MR contrast agent for brain tumor perfusion MRI than ionic agents. Keywords DCE MRI,Contrast Agents,Rodent Brain Tumor model Methods: Three different groups of raters (non-experienced volunteers, medical students and neuroradiologists) segmented tumor-related FLAIR changes and contrast-enhancing tumor tissue in four patients with glioblastoma (3 male, mean age at imaging 59.3 ± 13.9 years) in initial and follow-up MR-scans (figure 1). One rater did repetitive segmentations of the initial MRI to address intra-rater-reliability. All patients underwent high-resolution MR imaging including a 3D fluid-attenuated-inversionrecovery (FLAIR) sequence and a 3D T1-weighted magnetization prepared rapid gradient echo (MPRage) sequence without and with contrast agent. Tumor segmentation was done using a semi-automated segmentation tool based on a region-growing-algorithm with 3D-interpolation. Tumor volume was compared between the different groups of raters by calculating the intra-class-correlation (ICC) for the inter-and intra-raterreliability and the root-mean-square error (RMSE) to determine the precision error as well as the least significant change (LSC).

Result: Semi-automated tumor segmentation was performed with excellent intra-and inter-rater-reliability. Purpose: Pseudoprogression is common and represents approximately one third of all patients with high grade primary brain tumours treated with concurrent chemo and radiotherapy. It looks similar to disease progression on the conventional MRI. The purpose of our study was to evaluate the role of advanced MRI techniques such as MR Spectroscopy and MR Perfusion to differentiate pseudoprogression from true progression. Methods: CASPER electronic referral system was interrogated for all brain tumour patients undergoing radical chemoradiotherapy or radical radiotherapy between January 2010 and Sep 2014. Patients who clinically deteriorated and had early MRI scans were selected. Of these, the scans that raised the concern for pseudoprogression but disease progression could not be excluded were discussed at the Neuro-Oncology multidisciplinary team meeting (MDT). MR Spectroscopy and Dynamic contrast-enhanced MR perfusion were recommended for 10 patients to further clarify the nature of these lesions.

We then retrospectively evaluated the clinical and radiological outcomes for these 10 patients in detail. Result: Out of 10 patients, there were 4 females and 6 males. There mean age was 49 years (range 20-66). 9 were high grade gliomas (6 were grade 4, 3 were grade 3) and 1 was anaplastic supratentorial ependymoma. All these patients were treated with radical intent. 8 underwent primary debulking and 2 had a biopsy. 6 had chemoradiotherapy and 4 had radical radiotherapy in adjuvant setting. Average time of clinical deterioration was 8.1 months. For MR Spectroscopy, 8 patients demonstrated tumour spectrum which was reported as tumour progression. 1 had a non-viable spectrum and 1 was reported as indeterminate.

For the Dynamic contrast-enhanced Perfusion, 5 had increased perfusion (with rCBV of =/>4) and all of these behaved as true disease progression clinically. 5 had rCBVof less than 4 and all these subsequently improved on follow up scans. The management of all these patients changed based on the radiological reports and after discussion at the MDT. Purpose: To evaluate the ability of functional diffusion mapping (fDM) to predict treatment response in patients with brain metastases undergoing stereotactic radiosurgery (SRS) or radiosurgery. Methods: Twenty-four patients, 10 male and 14 female (54.81 ± 9.89 years, mean ± standard deviation) were analyzed. A total of 38 metastases comprising different size (0.23-13.01 cm3). They were studied with standard MR sequences on a 1.5-T MRI (Siemens Symphony, Erlangen, Germany) with a 6-channel phased-array spine coil. They comprised 3D spoiled gradient recalled echo (SPGR), T1 contrast-enhanced weighted images and Diffusion spin echo, echo-planar acquisition (b 0/1000) weighted images before and at least 3 month follow-up after therapy. Images were nonlinearly co-registered to T1-weighted pretreatment scans. Diffusion changes were quantified and presented as a functional diffusion map (fDM). The predictive values of percentage of change in whole-tumor volume, mean ADC and fDM parameters for treatment response were evaluated by WHO response criteria. All data analysis was performed using a statistical package (IBM SPSS statistics version 20, Somers, NY, USA) Result: Out of the 38 metastases analyzed, 18 were classified as partial response (PR), 10 as stable disease (SD) and 10 as progressive disease (PD). Normalized volume values of the metastases for each response group were obtained, disclosing that apparent diffusion coefficient increase was a good predictor of response (PR). So, sensitivity was 88%, specificity 100%, positive predictive value 100% and negative predictive value was 94%. After 3 months after initiation of therapy, the percentage of tumor volume with significant ADC increase was the strongest predictor of treatment response than the changes in whole-tumor volume and mean ADC values determined at the same time point as compared to their pretherapy values. year-old age were excluded. Transverse ONSD (in both right and left sides) was measured on axial brain sections at 3 mm behind the globe using MRI (T2-wieghted images) and CT scan (brain window images).

The study was approved by the Institutional Review Committee.

Result: There was a linear, strongly positive and statistically significant correlation between mean ONSD measured by CT scan and MRI (r=0.984 and p value <0.001). Using intra-class correlation (ICC), the agreement between means of CT-and MRI-derived ONSDs in all cases was almost perfect with ICC=0.987 and p value <0.001 as almost all readings were distributed tightly around the midline of the acceptable difference of 0.2mm. Agreement was also almost perfect when stratifying ONSD readings into normal (< or =5mm) and thickened (>5mm) We analyzed the postoperative MRI, focused on the residual enhancement at the tumor bed on the contrast enhanced dynamic coronal images. We defined the residual tumor as surgically confirmed lesions by reoperation, or the residual enhancing lesions which were stable or growing in size on the follow-up MRI.

The residual enhancing lesions were divided into three groups: peripheral enhancement, nodular enhancement, and peripheral and nodular enhancement. In each group we measured thickness and size of residual enhancing portion and compared the difference between residual tumor and postoperative change.

Result: In 19 patients, residual tumors were found, and most patients (74%) showed nodular enhancement (n=14) and peripheral enhancement (n=3) or peripheral and nodular enhancement (n=2) were also seen. Of 52 patients, thirty-three patients showed peripheral enhancement with the mean thickness of 1.8mm (range, 1.0-6.2). The mean thickness of peripheral enhancement without residual tumor was 1.6mm (range, 1.0-3.8) and the mean thickness in residual tumor was 4.6mm (range, 2.9-6.2). Nodular enhancement was seen in sixteen patients with the mean size of 8.6mm (range, 3. Result: Immediate angiographic occlusion was achieved in 6 cases, near complete in 3 and incomplete occlusion in 12. After the procedure, silent lesions on 24-48 hours DWI were also evaluated . The Flow disrupters devices present a marked signal void in all sequences. However neck or sac patency can be evaluated also without injection and correlations with angiographic aneurysm occlusion was 80%. The thrombosed aneurysmal sac is evident in PD and T2 sequences. AT1 halo hypersygnal is seen in thrombosed anevrysm with a 91.6% correlation with the DSA that we supposed being the thrombosed space in between the device and the anevrysm wall. A "crescent moon sign", due to the device shape is seen in TOF sequences: in case of persistent flow, this appeared modified in the injected sequence. Conclusion: At the present time, the DSA is mandatory in the follow up of aneurysm treated by intra-aneurysmal flow divertion devices, however, preliminary results suggest the MRI is an efficient and fiable tool in assessing the degree of occlusion of the aneurysm treated by that the Flow disrupters LUNA™ and the WEB ™devices. Keywords Aneurysm,Flow disrupter,MRI

Methods: After approval from the institutional ethics committee was obtained, 25 consecutive patients with unruptured paraclinoid were prospectively evaluated using a high-resolution 3D-PD ATSE MR imaging technique with coronal plane perpendicular to the diaphragma sellae. The MR images were analyzed for identification of DDR, surrounding regional anatomical structures, and paraclinoid aneurysm. The locations of the aneurysms were categorized into intradural or extradural. The imaging findings were compared with the angiographic or surgical findings. Result: All 25 aneurysms were identified by high-resolution 3D-PD ATSE MR imaging, which showed the accurate locations in regards to DDR and other adjacent anatomical landmarks. The aneurysm locations were 14 intradural and 11 extradural. A comparison between high-resolution MR imaging and conventional angiography revealed discordant anatomic locations in 7 aneurysms ( 7 of 23, 30% Purpose: Ruptured blood-blister-like (BBL) aneurysms represent a therapeutic challenge. Timing of treatment and technique of choice are still a subject of debate. We report our experience in the endovascular treatment of such lesions in the subacute phase. Methods: Between june 2011 and January 2015, 6 ruptured BBL aneurysms were treated at our institution. Four were located in the carotid siphon, 2 in the posterior circulation. Endovascular procedures were carried out between day 7 and day 15 after the hemorragic event. One patient was treated surgically. Flow-diverter stents (FDS) were used in 4 cases. Two telescopic laser-cut stents were used in one case. Double antiplatelet therapy was started 4 days before treatment in 1 case and the day of the procedure in the remaining 4 cases. Angiographic follow-up was carried out by MRA and DSA at 1 month, 6 months and 1 year. Result: All endovascular procedures were performed without technical difficulties. Antiplatelet treatment was started 4 days prior to procedure in one case and the day of the intervention in the other cases. One patient presented a transient motor deficit at day 1 after treatment. One patient had a peroperative cerebellar ischemia after FDS deployement, despite antiplatelet treatment. One patient treatd by surgery had a fatal brain ischemia after peroperative aneurysmal rupture that eventually required clipping of the carotid siphon. Imaging follow was available for the remaining 5 patients. No patent rebled prior to treatment or during followup. Three out of five aneurysms were completely occluded at latest follow-up. Conclusion: Modern endovascular techniques for the treatment of ruptures BBL aneurysms, including the use of flow-diversion, seem promising. Treatment in the subacute phase may be considered as an option in relation to other clinical issues (patient WFNS grade, risk of rebleeding under antiplatelet therapy, ventricular shunting) when pondering overall risks and benefits in patient management. Keywords Blood-blister-like aneurysms,flow diversion,subacute phase Purpose: Endovascular treatment of wide neck brain aneurysms can be very challenging, particularly wide-neck bifurcation intracranial aneurysms are still very difficult to manage and represent an obstacle to safe and effective endovascular treatment that has not yet been solved. WEB is an intrasaccular flow disruption device, placed within the aneurysm pouch, creates blood flow stasis with subsequent thrombosis. Because the flow disruptor device is placed wholly within the aneurysm, the need for antiplatelet therapy is eliminated an then this intrasaccular treatment is potentially valuable in ruptured aneurysms. WEB treatment of recanalized aneurysms also seems feasible. The first double layer version of the WEB devices presented some troubles in its feasibility with a not negligible rate of recurrence. We report our experience with both versions, double and single layer, of the WEB device. Methods: Since June 2012, 10 patients with 10 brain unruptured aneurysms, were treated at our institution using WEB devices. The former 2/10 aneurysms were treated using the double layer initial version of the WEB device. The latter 8/10 ones were treated with the new single-layer version. All treated aneurysms were unruptured. Five out of 10 aneurysms were located at MCA bifurcation (5 small), 1/10 at Acomm bifurcation (small), 3/10 at intracranial carotid bifurcation (2 medium, 1 small), 1/10 basilar tip (small). Follow-up was performed by MRI at one month in 10/10 aneurysms, while just 2/10 have reached one year followup performed by both MRI and DSA. Result: All treatments were performed without any procedural and post-procedural complication. Follow-up showed recurrence in 1/10 aneurysm (10%). This case, successfully retreated with p-Conus device, will be discussed. It referred to the first case in our experience and, as previously mentioned, it was performed with a double layer WEB device. Conclusion: According to our preliminary experience, despite some troubles during first treatment, WEB endosaccular device revealed safe and feasible. Feasibility improved using single layer device that looked softer and more reliable than the stiffer double layer one. To obtain optimal results, the importance of initial measurements has to be stressed. Purpose: Y-configured stent-assisted coiling is a promising therapeutic option to ensure safe coil embolization and preserve the affected arteries in complex wide-necked aneurysms. We present our experience with selfexpanding Acandis® Acclino® stents for the treatment of complex aneurysms using the kissing-Y technique. Methods: We retrospectively reviewed seven patients with seven complex aneurysms (three anterior communicating artery (AcomA), two middle cerebral artery (MCA), one basilar artery (BA)/ superior cerebellar artery (SCA), one vertebral artery (VA)/ posterior inferior cerebellar artery (PICA)) who were treated with the kissing-Y technique by stent assisted coiling from June 2013 to July 2014 with a follow-up until January 2015. DSA follow-up ranged up to 17 months with a mean follow-up period of 10 months. Six patients were treated electively and one in the acute phase of a subarachnoid hemorrhage. In all cases closed-cell Acandis® Acclino® stents were used. We evaluated procedural complications, clinical outcomes and midterm angiographic follow-up. Additionally, a literature review is provided.

Result: In all patients, stents were successfully placed and implanted. One patient developed a periprocedural thromboembolic complication not directly related to the stents. No other peri-or postprocedural complications were encountered. Follow-up examinations showed stable and total occlusion of all coiled aneurysms. Conclusion: The results of our study show that the kissing-Y technique using closed-cell Acandis® Acclino® stents followed by coil embolization is a feasible treatment option for selected complex bifurcation aneurysms. 

A wide variety of lesions in and around the orbita can impair eye movement. CT and MR imaging is frequently used to confirm or exclude lesions in and around the orbit in patients with orbital lesions.

First of all it is very important to know the exact clinical history of the patients. CT is excellent for confirming a mass; however MRI is more sensitive and arrives often at a single most likely diagnosis. Characteristic imaging features may help distinguish among lesions that have overlapping clinical presentations. This review focuses on some of the common benign and malignant orbital masses. Vascular lesions include capillary (infantile) hemangioma, cavernous hemangioma, and lymphangioma. Benign tumors include optic nerve sheath meningioma, schwannoma, and neurofibroma. Malignancies that are reviewed include: lymphoma, metastasis, rhabdomyosarcoma, and optic glioma. In addition the orbital pseudotumor and orbital infections will be discussed.

High-resolution temporal bone imaging with Multi-Detector-Spiral-CT (MDCT) and Magnetic Resonance Imaging (MRI) provide substantial information for the correct diagnose of inflammatory disease and potential complications.

MDCT is performed in the axial plane with coronal/sagittal reconstructed planes. The acquired section thickness should be submillimeter e.g. 0.6mm/0.5mm, the FOV~20cm, the matrix >512x512, the reconstructed section thickness 0.6-1.0, and a HRCT bone window level setting should be obtained. MRI is performed with an axial FLAIR or T2w FSE of the head, and a 3D T2w high-resolution thinsection sequence in the axial plane, a diffusion-weighted sequence in the coronal plane, and a T1w sequence before and after the intravenous application of contrast material in the axial plane and additionally (if necessary) in the coronal plane. The section thickness of the 3D T2w high-resolution thin-section sequence should be in the submillimetre range and of the T1w sequences should be 1 mm. The FOV~20cm and the matrix >512x512. The DWI should have a thickness of about 3 mm and fast techniques should be used instead of Epitechniques. Inflammation and infection may occur in the external, middle, and inner ear. Resulting from chronic inflammation are secondary cholesteamas. They mainly affect structures of the middle ear, but can also yield to severe complications e.g. when invading the intracranial region. Inflammations can also occur in the labyrinth or in the petrous apex. In this lecture, the imaging characteristics of the various forms of inflammation and infection beside those of acquired cholesteatomas and the differential diagnosis will be shown.

Extracerebral lesions related to the temporal bone can have their origin in the cerebellopontine angle (CPA) and internal auditory canal (IAC), middle ear, external auditory canal (EAC), mastoid, jugular foramen and petrous apex. Although CT can show the bone alterations, MR is the method of choice as the signal intensities provided by the different sequences help to characterize the lesions. The most frequent tumoral lesions are of course acoustic schwannomas, paragangliomas, meningiomas and epidermoid tumors. These are well known and will only be briefly discussed, especially how to differentiate them from one another in difficult cases or how to recognize potential atypical behavior. Less frequent lesions like lower cranial nerve or facial nerve schwannomas, lipomas, hemangiomas, metastases and lymphomas in the CPA and IAC are less frequent and pose more difficulties. Middle ear lesions are less know and apart from facial nerve schwannomas and paragangliomas one can also find hemangiomas, meningiomas and adenomas as well as malignant tumors with extension to the middle ear, including head and neck malignancies with extension to the m i d d l e e a r a n d Chondrosarcomas, giant cell tumors, histiocytosis, Ewing sarcoma, endolymphatic sac tumors etc. can be found in the region of the petrous apex/mastoid and must be distinguished from benign lesions like cholesterol granuloma. The characteristics of the most frequent occurring lesions in the CPA, IAC, middle ear, petrous apex and EAC will be discussed and illustrated in this lecture.

The rational and effective analysis of the masses and pathologies arising in the suprahyoid neck necessitates the exact localization according to the anatomical spaces. There is a certain overlap, sometimes resulting in confusion, between the anatomic and surgical borders and definitions of the neck spaces. It is necessary for the clinical radiologist to elucidate the complex anatomical relationships from a radiological point of view and to present the critical contents of each space. Thus, a space-orientated differential diagnosis may be facilitated and according to the location and the typical imaging appearance of various lesions the differential diagnosis may be narrowed down to specific pathologies. Common pathologies in the vicinity of the critical contents as well as pathologies extending beyond one anatomical space are also of major interest for the radiologist and crucial for the patient's treatment. Therefore, imaging surveys should be meticulously read for such imaging findings.

The purpose of this lecture is to review current imaging protocols for the evaluation of sinonasal CT, cone bean CT (CBCT) and MRI in the context of infection and inflammation, to provide an understanding of the impact of clinical findings on the choice of the respective imaging protocol and to provide a checklist of what the neuroradiologist needs to report. Basic concepts of sinonasal CT and CBCT are reviewed including protocols, radiation doses, 2D and 3D reconstructions and the administration of contrast material. A brief discussion of the pertinent anatomy including the most relevant radiological anatomical landmarks will follow. The added value of MRI in specific situations is equally discussed. The low back pain (LBP) is the second most frequent cause of medical consultation in all western countries. LBP is more often idiopathic and have as most frequent the internal disc disruption (IDD) and it is referred to as discogenic pain. IDD consists in anular fissures, disc collapse and mechanical impairment eventually associated to endplates failure and is considered as a separate pathogical entity in respect to other painful conditions such as degenerative disc disease, disc herniation and segmental instability. Discogenic pain has either a mechanical and an inflammatory genesis. The radicular pain is most often generated by a disc herniation or a spinal canal stenosis. Facet pain may be due to degenerative changes and osteoarthritis. Because of the rich innervation facet joints can be a direct source of pain or can cause compression of nerve roots in lateral recesses and in the neural foramina. Disc and facet joints degeneration can cause segmental instability being another common cause of axial and radicular pain and chronic disability. The complex anatomy innervations and function of the spine render challenging the clinical assessment of pain pain with advanced imaging being often not confirmatory because similar changes are found in either asymptomatic and ill subjects. Clinical correlation is always mandatory and therapy cannot rely solely upon imaging abnormalities. The knowledge of pathophysiology of discogenic, radicular, facet and dysfunctional pain and the role of imaging in each one of these pathologies is the fundament for a correct approach to spinal patients.

Thien Thanh Dang Vu (Canada)

Brain imaging studies have provided key insights into the neural causes, consequences and correlates of sleep disorders. During normal sleep, functional neuroimaging data revealed specific changes in regional brain activity correlated with electroencephalographic sleep oscillations. Neuroimaging studies in insomnia support the global hyperarousal hypothesis, by showing decreased inhibition during the transition from wakefulness to sleep. In addition, neuroimaging findings in insomnia also demonstrated alterations located in prefrontal and parietal cortices, possibly in relationship with cognitive deficits, and showing partial recovery following cognitive behavioral therapy. In narcoleptic patients, both functional and structural abnormalities were found in the hypothalamus, supporting a hypocretinergic dysfunction, whereas altered limbic responses may relate to emotional dysregulation contributing to the onset of cataplectic episodes. Neuroimaging studies of obstructive sleep apnea have shown alterations in the prefrontal cortex, hippocampus and parietal cortex in relationship with neuropsychological deficits. Some of these changes were reversible by treatment with continuous positive airway pressure. Lastly, functional and structural neuroimaging studies of rapid-eyemovement sleep behavior disorder converged on pontine abnormalities, as well as presynaptic dopamine dysfunction related to the development of synucleinopathy.

16:30-18.30Spine Treatment S14.1 Vertebral porotic fracture: EBM of percutaneous treatment

This is an analysis of the treatment of osteoporotic compression fractures using evidence based approach. The categories of guidelines, appropriate use criteria, coverage, and payer policy review are segmented in the evaluation. The goal is to understand where evidence based fits in the overall treatment plan of patients with osteoporotic compression fractures.

Percutaneous disk treatment can be performed for two main indications: disk-related radicular pain, and discogenic axial cervical or low-back pain. This lecture will focus on radicular pain indications. Radicular pain related to a disk problem can be caused by direct mechanical compression on the nerve root, by vascular congestion, by inflammatory phenomena, or often by a combination thereof. Several intradiscal minimally invasive percutaneous techniques have been developed to treat radicular pain, implying intra-discal injections of different substances, or intra-discal insertion of devices with different mechanisms of action, to achieve biological-pharmacological or deconstructive (disc removal, remodeling, shrinkage) effects.

Most commonly the target of these procedures is the nucleus polposus, at the center of the disk, but in some cases an extruded disk fragment can also be targeted (disk fragmentectomy). This lecture will focus on rationale, indications, benefits, limitations of different treatment techniques. Imaging guidance techniques, with fluoroscopy and CT will be discussed. Technique-specific elements will be reviewed. Possible risks, complications, and ways to avoid them will be discussed.

Allan L. Brook (USA)

Sacral insufficiency fractures were originally described, by Lourie in 1982. Sacral insufficiency fractures primarily occur in older females, and as our population continues to age, we expect to see a rise in the incidence. Sacroplasty assists in sacral stabilization. CT, whether utilized alone or in combination with fluoroscopy, dramatically improves visualization of the sacrum and the critical neural bearing structures within its substance during the sacroplasty procedure. Sacroplasty is an established effective procedure for the treatment of painful osteoporotic sacral insufficiency fractures. Sacroplasty can also be utilized in the management and treatment of painful sacral neoplastic lesions. The aim of this work was to evaluate thalamo-cortical FC changes in patients with secondary progressive (SP) MS, as compared to both RR and healthy subjects (HS), and to investigate correlations with cognitive impairment. Methods: Fourthy MS patients (20 RR and 20 SP) and 20 HS underwent a 3 Tesla fMRI at rest; they were also scored with PASAT. Data were analysed with tools from FMRIB Software Library; the seed-based method was used to identify the thalamic RS network (RSN). Result: Thalamic RSN was altered in both SP and RR with respect to HS, with greatest FC abnormalities in SP. In particular, thalamo-cortical FC was lower in RR than in HS in left temporo-occipital, frontal and parietal cortices, bilaterally and in the cerebellum; SP showed decreased FC in the same brain areas, which were even more extensively affected, and, in addition, in the medial thalami. Thalamo-cortical FC was higher in RR than in HS in the right frontal and in the occipital and cingulate cortices, bilaterally; SP showed increased FC also in the right temporo-occipital cortex, hippocampi and posterior thalami, in addition to the aforementioned areas. PASAT scores were significantly lower in patients than HS and in SP than in RR. In RR, PASAT scores significantly correlated with thalamo-cortical FC in the frontal cortex bilaterally, thalami and left anterior insula, indicating that worse the performance greater the FC. In SP widespread hyperconnectivity, including the cerebellum, thalami, posterior cingulate, anterior insula and multiple foci in the whole cerebral cortex, inversely correlated with PASAT scores. Conclusion: Our data indicate that thalamic RSN is progressively altered in the two MS subtypes: SP showed more extensive patterns of both decreased and increased FC than RR. Moreover, the correlation between cognitive impairment and increased thalamo-cortical FC suggests that the recruitment of additional areas within the thalamic RSN is unable to prevent the cognitive decline. Purpose: Although the relationship between cerebellar function and balance capability is well known, only few study explored cerebellar functional connectivity abnormalities underlying clinical impairment in Multiple Sclerosis (MS) and no one was focused on postural deficits. The aim of our work was to investigate, by using resting-state functional MRI (rs-fMRI), the alterations of functional connections between the cerebellum and other brain structures in MS patients and their role in balance regulation. Methods: Thirty patients with relapsing-remitting (RR) MS and 25 healty subjects underwent a 3 Tesla rs-fMRI and a static posturography to calculate the body's center of pressure displacement (COP path). Functional MR imaging data were analyzed with tools from FMRIB Software Library, by using the seed-based method to identify the cerebellar RS network (RSN); both dentate nuclei were used as seed region. Result: As compared to HS, patients had worse postural stability. FMRI analysis revealed an altered connectivity within the cerebellar RSN in RR-MS patients, with an increased connectivity in several brain areas mainly belonging to the prefrontal cortex, bilaterally (P < 0.05, cluster level corrected). Moreover, in the patient group, a significant inverse correlation was found between the length of COP path and the increased functional connectivity in the left dorsolateral prefrontal and orbitofrontal cortices (P < 0.001, uncorrected). Conclusion: These results show an increased functional connectivity within the cerebellar RSN in MS patients, mainly involving the frontal cortex.

The association between increased functional connectivity in some frontal cortical areas and less severe postural deficit suggests that neuroplastic changes in these areas play an adaptive role in balance regulation. Keywords MULTIPLE SCLEROSIS, FUNCTIONAL CONNECTIVITY, FMRI There was no significant age difference between all groups, or difference in disease duration or total steroid use between patient groups, and study approved by the local Institutional Review Board. All scans were performed on 3T MRI scanner (Achieva, Philips Healthcare). For DTI, 4 averaged minimally weighted (b0) and 2 averaged 15 gradient directions with b value of 1000 s/mm2 were acquired using single-shot EPI sequence with: TR/TE = 9150/65 ms, reconstruction resolution = 2x2x2 mm3, 70 axial slices, SENSE factor = 2. 3D-MPRAGE T1-weighted images for anatomical reference, and axial T2weighted images to exclude structural abnormalities obtained. DTI-derived metrics (fractional anisotropy (FA)) using FDT, and tractbased spatial statistics (TBSS) performed. Brain tissue volumes including peripheral grey matter (GM) and total brain parenchyma, and 9 subcortical structures were estimated by Sienax and FIRST. Using SPSS, twotailed unpaired T-test for volumetric differences between all groups was performed, p-value 0.05 to be significant. Based on TBSS results, correlation analysis between DTI-derived indices of genu of corpus callosum and the left and right thalamic volumes of all groups made. Result: Periventricular T2 signal abnormalities were seen in some of NPSLE and SLE patients, but not involving the corpus callosum.

Marginal atrophy observed in the peripheral GM, total brain parenchyma, right and left thalamic nuclei (but no other subcortical nucleus) of NPSLE when compared to HC (all p< 0.05). TBSS showed extensive FA decrease such as genu and splenium of corpus callosum, bilateral superior and inferior longitudinal fasciculus in NPSLE versus HC (see Figure) , but not in SLE vs HC. There is significant positive correlation between FA Changes of the MT-ratio (MT), a semi-quantitative marker of tissue integrity, have been reported prior to lesion appearance on conventional sequences. MTR-results, however, are difficult to interpret as they reflect a combination of sequence, relaxation and quantitative MT (qMT)-parameters, such as the ratio of the restricted to the free proton pool size (F), the exchange rate between the two proton pools (kf), and T1-and T2-relaxation times (T1/ T2). Here, the diagnostic potential of fast qMT-imaging of MSlesions is assessed.

Methods: Nineteen patients with active relapsing-remitting MS were examined bi-monthly for 12 months at 1.5T (Siemens, Avanto) with PDw/T2w, T1w-/+ contrast-enhanced sequences, and MT-imaging. QMT-imaging included a B1-map, two RF-SPGR sequences with variable flip angles for T1-determination, 2 bSSFP sequences with variable flip angles for T2-determination, and 9 bSSFP scans using different RF pulse durations and flip angles to yield F, kf, and MTR. QMT-imaging was acquired within 8 minutes (isotropic resolution of 1.3 mm3). All newly appearing lesions during the study were semiautomatically segmented on whole-brain PD/T2w sequences and registered to the MT-maps of the previous and following MR-time points to track the lesion evolution longitudinally. QMT-values were normalized to the respective values of normal appearing WM. Lesional MT-changes were pronounced at the time of lesion appearance on conventional MRI, but not seen earlier with any MT-parameter. Average lesional qMT-changes were characterized by reduced F and kf (-39%, -46%), prolonged T1 and T2 (+14%, +36%), whereas MTRchanges were smaller (-13%). Reversed trends were observed 2 months later for qMT-parameters (F -35%, kf -38%, T1 12%, T2 28%), while MTR remained almost unchanged (-13%). Conclusion: Rapid whole-brain MT-bSSFP-imaging is feasible in 8 minutes. With bi-monthly MT-imaging, MS-lesions cannot be detected earlier than on conventional imaging. Lesional qMT-parameter changes are more pronounced than MTR changes. QMT-imaging provides quantitative tissue characteristics and allows studying the evolution of MS-lesions. QMT-imaging might thus be a useful adjunct for the diagnostic assessment and treatment monitoring in MS. There was statistically significant correlation between age and total volume of hippocampus in study group (n=81; r=-0,393; p<0,001) and control group (n=87; r=-0,582; p<0,001).

Analysing ten word memory test correlation with standardized hippocampal volume reduction there was low correlation with high p valueanalysing short term memory (n=24; r=0,142; p=0,254) and long term memory (n=24; r=0,164; p=0,222); correlating Woodcock-Johnsons cognitive productivity test performance with standardized hippocampal volume reduction there was also low correlation (n=13; r=0,090; p=0,385). Conclusion: Even though initial results show no statistically significant connection between hippocampal volume reduction and cognitive tests, correlation coefficient indicates connection between hippocampal volume reduction, memory performance and cognitive productivity in patients with clinical signs of early cognitive decline. High hippocampal volume variability in study group could be explained with human cognitive function complexity. Also hippocampus plays significant role in memory and cognitive productivity performance, but there are other parts of brain which could have major impact on tested cognitive functions. Result: Anterior thalamic radiation and cingulum-cingulate gyrus were damaged in DLB (p<0.003), whereas cingulum-angular bundle was disrupted in AD (p<0.005). In DLB patients, secondary axonal degeneration within anterior thalamic radiation was related to microstructural damage within medio-dorsal thalamus (p<0.05), whereas axonal degeneration within cingulum-angular bundle was related to precuneus thinning (p<0.05). Conclusion: We posit that structural connectivity is affected within fronto-thalamic network in DLB and within mnemonic pathways in AD. Furthermore, the high correlation between GM and WM metrics within anterior thalamic radiation suggests that the structural connectivity alteration of these pathways could be caused by GM neuronal loss rather than by direct WM injury. Thus, this finding supports the key role of cortical and subcortical atrophy in DLB. Multiple reasons can account for a rise in intracranial pressure (Pseudotumor cerebri syndrome, PTC), but frequently those reasons remain obscure (idiopathic Pseudotumor cerebri, idiopathic intracranial hypertension). In this speech, I am going to summarize the role of neuroimaging in the diagnosis of these entities. We will start recapitulating a few principle facts on brain/CSF pressure and why pressure can rise. It is emphasized that clinical signs and symptoms in patients can be unspecific so that choosing to look for MR-signs of PTC and selecting an appropriate MR protocol is essential. The audience will be familiarized with typical features of increased intracranial pressure such as optic-nerve sheath hydrops and "empty-sella" that can quite easily be interpreted using a combined MRI protocol covering the orbit, the pituitary, the brain and the venous sinuses. Ventriculomegaly and narrowed ventricles can occur in patients with increased pressure but looking at the size of the ventricles often is misleading.

To know this can be especially important in interpreting MRIs of shunt-operated patients with long-standing hydrocephalus and suspected increase or decrease in CSF pressure. Case reports of patients with different etiologies will be presented to highlight common and disparate features of raised intracranial pressure. The importance of sinu-venous stenoses in patients with "idiopathic" and "secondary" Pseudotumor cerebri will be discussed and diagnostic pitfalls shown. It is the aim of the speech to increase the awareness that MR imaging emerges as the single most-important tool in investigating disorders of deranged intracranial pressure.

Gralla Jan (Switzerland)

Various clinical conditions can cause CSF low pressure syndromes. Common pathologies are CSF leakage following lumbar puncture and surgical intervention as well as over shunting. A diagnostic and therapeutic challenge is the spontaneous occurrence of CSF leakage. Despite typical clinical symptoms mainly characterized by orthostatic headache, the cranial and spinal MRI can reveal characteristic signs such as subdural fluid collection, saggital sagging of the brain, engorgement of veins and meningeal enhancement. Spinal infusion test and dynamic opticus ultrasound might complete diagnostics work-up. However, in cases of spontaneous CSF leakage detection of leakage site is demanding. Extrathecal fluid collections on high spatial resolution T2 or SPACE spinal MRI indicate the approximate location of leakage site; leakage itself might be proven by the intrathecal application of gadolinium application. However, due to low temporal resolution of MRI imaging, the value of the method to precisely locate leakage site is limited. In case of failed conservative treatment (bed rest), lumbar or local blood patch application has a high rate of clinical success. In case of surgical repair, the localization of leakage site and determination of the underlying pathology (e.g. focal disc hernia, boney spur or perineural cysts) is required. In this case leakage site can often be illustrated following intrathecal administration of iodine contrast media and dynamic evaluation of the spine under fluoroscopy (dynamic myelography).

In the last few years, a vast number of studies have demonstrated that Next Generation Sequencing (NGS) is the best method to discover small variations in genetically heterogeneous conditions, in which different genes can be involved with overlapping phenotypes. In the pre-NGS era, the large variability of human DNA sequences and the occurrence of several pathogenic variants in the same individual were overlooked. We have developed and applied different NGS-based platforms, named MotorPlex, Lysoplex, etc, to test 100-900 disease genes or candidate disease genes for neuromuscular disorders or diseases involving the lysosome-autophagy pathways. More than 1000 individuals have been sequenced so far. The sensitivity and specificity of these approaches are higher than whole exome sequencing. We concluded the genetic diagnosis of a specific and expected Mendelian condition in up to 60% of cases, while in the remainder of cases further studies are required. Trio analysis was always necessary to improve the interpretation of results and to facilitate validation steps. To cover the gaps of NGS, we are using additional tools, such as Motorchip (ArrayCGH), RNA-Seq or MLPA.

Our study represents one of the largest screening of neuromuscular patients and demonstrates the importance of NGS in the diagnostic flowchart. Considering the decreasing cost of NGS and the rapid evolution of targeting methods, these methods are the best upcoming tests for initial approach of complex patients. S15.5 Drug discovery in neurosciences: challenges and opportunities

Many drug companies have scaled down their efforts in CNS diseases due to the high failure rates of development experienced in the past 15 years, particularly in the field of Neuropsychiatric diseases. Yet, the burden of CNS diseases continues to grow worldwide.

In this presentation, we review the current trends in addressing this core challenge. A central problem is to develop more precise and objective measurements of CNS function. Recent advances in human genetics and genomics coupled with better in vivo biomarkers in patient samples from specific patient populations will be key to further advances.

For example, studies of the genetics of Autism and Depression or Amyotrophic Lateral Sclerosis have revealed a number of potential therapeutic targets. Progress in imaging and sensitive biomarkers now permit a more reliable assessment of early stages of Alzheimer's disease, a requisite to the discovery of disease modifying therapeutics. Other examples will be illustrated.

Gioacchino Tedeschi (Italy)

Functional magnetic resonance imaging (fMRI) techniques are one of the most useful technique investigate the neural circuitry involved into the pathogenesis of several brain disorders. Very briefly, the measurement of blood oxygen level dependent (BOLD) signal, based on the differences between magnetic characteristics of oxy-and deoxyhemoglobin, reflects neuronal activity and can visualize changes in the BOLD contrast, with high temporal and spatial resolution. BOLD-fMRI studies can be conducted using a block or event-related experimental designs. Block design experiments are characterized by blocks of identical trial types to establish a task-specific condition, whereas event-related experiments are modelled as the linear summation of the hemodynamic response to discrete events (e.g. experimental pain stimulation or drug intake). More recently, BOLD-fMRI in the absence of experimental tasks and behavioural responses, performed during "resting" state (RS-fMRI) has allowed the exploration of brain connectivity between functionally linked cortical regions. To study multiple systems simultaneously without a priori definition of region of interest, independent component analysis (ICA) algorithms are usually used. ICA transforms individual patient RS-fMRI data sets into series of resting-state networks (RSN) maps such as the default mode, the executive, the sensorimotor and the visual networks.

We shall present an overview of above-mentioned BOLD-fMRI approaches employed by our research group to better understand pathophysiological mechanisms in several disorders such as neurodegenerative diseases (Parkinson disease and parkinsonisms , amyotrophic lateral sclerosis, Alzheimer disease and fronto-temporal dementia), multiple sclerosis and migraine.

Experimental studies carried out over the last two decades have radically changed our knowledge about the motor system. The discovery of mirror neurons in monkey brain and the evidence in the human brain of a mirror mechanism, whose neural substrate most likely relies on mirror neurons, support the notion that the motor system not only plays a role in the execution of actions but is also involved in understanding actions and in coding the intentions of others' actions. This experimental evidence bring further the role of the motor system and extend its role to functions traditionally considered as cognitive. It is worth underlining that motor experience and motor competence seem to be a necessary pre-requisite for any cognitive function. The mirror mechanism first described as related to mirror neurons seems to be a more general functional mechanism in the brain, extending also to emotions and sensations: the neural substrates active when processing the emotions and sensation felt by other people are also active when we ourselves feel the same emotions and the same sensations. This in turn may constitute a biologically grounded link between us and other individuals. As for canonical neurons, since these neurons are fundamental for coding the properties of objects relevant for acting upon them, they may allow individuals to make experience of the external world and interact with the environment in the most proper manner.

11.00-13.00 Advanced diagnosis and Pediatric pathology S16.2 Infratentorial brain tumors-whats new

Posterior fossa tumours account for 45-60% of all pediatric brain tumours, and the most common infratentorial tumours include juvenile pilocytic astrocytoma, medulloblastoma, ependymoma, and brainstem glioma. Less commonly atypical teratoid-rhabdoid tumour and hemangioblastoma might be present. However, they are important to recognize as they radiologically mimic the more common tumors. Conventional and advanced MR imaging such as perfusion and diffusion are valuable tools in the work-up of these lesions. Also MR spectroscopy can be valuable especially in the diagnosis of medulloblastoma. Typically location, imaging appearance such cystic, solid or both, contrast enhancement, presence of calcifications are helpful in the differential diagnosis.

To provide correct diagnosis is important for treatment options and overall prognosis. In addition, new advances in molecular, immunhistological markers and genetic analysis have changed the view we evaluate some of these tumours with respect to grade, malignance, overall outcome and prognosis. This lecture will focus on some imaging points for the differential diagnosis of infratentorial brain tumors in children and review what is new with respect to molecular and genetic analysis with special focus on medulloblastoma.

Philippe Demaerel (Belgium)

The supratentorial intraaxial tumours will be reviewed. Generally speaking supratentorial tumours are more common in children below 2 years of age.

Astrocytomas are the most commonly type of intraaxial tumour and different subtypes can be distinguished. Primitive neurectodermal tumours are much less common but are interesting from the point of view of imaging because of the differential diagnosis with ependymoma and atypical teratoid-rhabdoid tumour. Ganglioglioma and dysembryoplastic neuroepithelial tumour have characteristic imaging appearances. Specific attention will be paid to the imaging appearances and differential diagnosis of suprasellar tumours.

The 'typical' imaging appearances and recent observations on pathology and genetics will be reviewed.. Imaging appearances on conventional MR imaging (T1 and T2-weighted, FLAIR and Gadolinium enhanced images) will be reviewed including the role of diffusion weighted images. Pial seeding is not uncommon in pediatric intraaxial tumours and the role of spinal imaging in the diagnostic work-up will be discussed. Finally the role follow-up imaging during and after treatment will be discussed.

Conventional MRI represents the backbone of brain tumor identification and characterization but has limitations in distinguishing tumors from tumor mimics, defining tumor grade, evaluating treatment response and predicting patient outcome. Advanced MRI modalities, such as diffusion weighted imaging (DWI), perfusion weighted imaging (PWI) and magnetic resonance spectroscopy (MRS) have improved our understanding of brain tumours. DWI gives information about the apparent diffusion coefficient of water and provides an opportunity to examine differences in cell density and tissue structure. PWI measures hemodynamic properties, such as tissue blood volume, and provides an indirect estimation of the degree of tumor angiogenesis. MRS estimates the levels of various metabolites within brain tissue that may be helpful for evaluating tumor aggressiveness. Beyond MRI, metabolic imaging with PET provides further complementary insights into tumor biology; depending on the radiotracer used, various molecular processes can be visualized and a growing body of evidence supports the promising role of radiopharmaceuticals that target amino-acid transport. Increased radiolabeled amino acid uptake in brain tumors correlates with increased use of amino acids for energy, protein synthesis, and cell division. Furthermore, as brain tumor uptake of amino acid tracers is predominantly determined by expression and activity of the L-amino acid transporter system, brain tumor visualization and characterization does not depend on the status of the blood-brain barrier, thus allowing amino acid uptake to occur in both enhancing and nonenhancing tumor components. The contribution of these methods to the evaluation of pediatric brain tumors is the focus of the present work. Susceptibility weighted images (SWI) is an MRI sequence originally designed as a vascular sequence, which has now gained attention to the clinical scenario due to its versatility in identifying blood and minerals. In newborns and infants SWI are particularly useful in depicting germinal matrix hemorrhages, intraventricular hemorrhage and superficial siderosis. SWI delineates the morphology of the arterial and venous vasculature, allowing to identify arterial and venous thrombosis as well as venous rupture. Vascular stasis associated with brain edema or enlargement of the venous structures in the setting of hemiplegic migraine represent other useful applications of this sequence. SWI depicts acute and chronic sequels of traumatic brain injury such as micro-hemorrhages, fatty embolism, and diffuse perivascular injury. Given its ability to enhance the signal intensity of the blood, SWI is used to evaluate vascular malformations including cavernomas, developmental venous anomalies, capillary telangiectasias, and arteriovenous malformations. The corresponding PHASE image can be of further assistance in distinguishing calcified lesions from tiny vascular malformations. In the presence of necrotic lesions, SWI in association with ADC map and single voxel spectroscopy guide the differentiation between necrotic tumors and abscesses. Finally, SWI is used in the evaluation of metabolicneurodegenerative and inflammatory disorders. At the end of this lecture, the attendees will be comfortable in using SWI as an additional tool in the diagnosis of vascular, neoplastic, inflammatory and infectious disorders of the CNS. Endovascular recanalization therapy of acute stroke patients with large vessel occlusion has become the most efficiant and accepted therapy. Succesfull recanalisation (TICI 2b and 3) with stentretrievers can be achieved in up to 75% of the patients, however that means up to 25% of acute vessel occlusions cannot be recanalized. The exact mechanism how stentretrievers work and interact with the clot is still unknown and a matter of intensive investigations. The clot itself shows a high variability concerning the length, location and composition.

Clot imaging with high resolution CT and MRI has the potential to describe the clot in more detail. It has been shown that the effect of treatment with iv.thrombolysis on the recanalisation rate depends on clot length but also on clot composition. Recent reports also demonstrated that the effect of mechanical recanalisation correlates with clot density in CT. Clotimaging may have the potential to prescribe the effect of different recanalisation therapies, while MRI has probably more potential to describe the composition of a clot than CT. This lecture will cover and discuss the different sources of clots, the mechanical properties of clots and the potential of clotimaging and the impact on treatment decisions. S17.2 Imaging for patient selection (MRI, CT)

Thromboembolic events are the leading cause of acute ischemic stroke. Reperfusion strategies are focused on attempted removal or disintegration of the thrombus / embolus with the objective of restoring an adequate flow in the hypo perfused, but still viable (penumbra), vascular territory. Restoring blood flow within a particular time window at the level of the ischemic penumbra leads to a reduction of the final size of the ischemic "core" and therefore to an improvement of the clinical outcome of the patient. In the last 10-15 years many studies showed that early recanalization of the obstructed vessel is the most important modifiable predictor of patient outcome. Despite the clinical efficacy of intravenous thrombolysis has been proven in numerous randomized trials, still about 50% of patients who suffer an ischemic stroke die or remain disabled. Patients with major neurological deficits, old age and a lack of recanalization after fibrinolytic therapy have a less favorable clinical outcome. The possibility of intra-arterial thrombolysis, alone or in combination with systemic one, may be a strategy to improve the outcome in patients who are not eligible for systemic therapy or in which there were no benefits after the same. This is common in patients with proximal vessels occlusion or with a high NIHSS scores. Endovascular intra-arterial procedures, both mechanical and pharmacological, are an alternative or additional option to intravenous thrombolysis. Their use, however, lead to negative or contradictory results in studies of past years. Four recent trials have demonstrated concordant and unambiguous evidence (level 1A) that thrombectomy is effective in patients with acute occlusion of major cerebral vessels. In each of the four trial patients were randomized to medical therapy (including tPA, if indicated) or medical therapy + thrombectomy. The number needed to treat to achieve a good functional outcome was 3-4. These trials have therefore called thrombectomy as a standard of care in selected patients with acute stroke. The criteria for selection of patients for thrombectomy are not yet defined. It is conceivable that they will be based on data from CT and CT angiography. For plain CT, ASPECT criteria are still considered valid (excluding patients with a score <7). The same evaluation can be performed with the same method on the partition images from CT angiography. Concerning this latter, it will be likely performed with biphasic technique. Those patients with a proximal arterial occlusion (M1/M2 MCA, vertebral or basilar artery) and efficient collateral flow should be candidate to reperfusion. CT perfusion is a further exam with potential in selecting these patients but there are no definite results concerning its clinical use. Despite the great potential of MRI (with diffusion and perfusion techniques) it is hard to imagine that MRI may play a role in this respect given the necessary extension of the diagnostic time that its use requires.

Objective:

To describe the new developments in the thrombolytic therapy New Drugs: Tenecteplase showed a greater reperfusion rate, a better NIH score at 24 hours and a higher rate of excellent or good recovery at 90 days than Alteplase Dilating the therapeutic window beyond 4.5 hours:

MR mismatch perfusion/diffusion shows the penumbra. Reversal of penumbra in the 3-to-9 hour-time window was associated with good clinical outcomes in 2 trials. Nevertheless the evidence suggests that 6 hours is the cut off for reversible ischemia, The procedure could be limited to the strokes with unknown time of onset or eligible for endovascular treatment.

Increasing efficacy through technology The nanotechnology allows to combine the effects of the biochemical enzymolysis to the mechanical force of a nanodevice resulting on thrombolysis acceleration Sonothrombolysis (CLOTBUST trial) proved better than thrombolysis alone in achieving complete recanalization and functional independence at 90 days Saving time A mobile unit equipped with CT and laboratory allowed a 6-fold higher proportion of golden hour thrombolysis, resulting in a significant higher rate of patients discharged home Coupling thrombolytic agents and mechanical thrombectomy 5 trials showed recently that thrombectomy plus IV thrombolysis is superior to IV thrombolysis alone in recanalization rate and good clinical outcome Conclusions At present a higher efficacy and safety of thrombolysis within a standard time window seems preminent. The trials on Tenecteplase and thrombectomy plus IV thrombolysis and the study on nanotechnology go in this direction and seem very promising for a significant improvement in the acute stroke management.

Importance: The SWIFT PRIME trial demonstrated superior outcomes in patients presenting with acute or moderate stroke who underwent endovascular therapy over patients who received intravenous tissue plasminogen activator (tPA) alone. Timely recanalization in large vessel occlusive disease is essential to achieving good outcomes in acute ischemic stroke (AIS). As such, the SWIFT PRIME study design incorporated aggressive time metrics and real time direct feedback. The benefit of such a quality initiative has not been systemically demonstrated in stroke patients undergoing mechanical thrombectomy. Objectives: We sought to understand the relationship between functional independence and time to reperfusion. We then systemically investigated the time intervals spent during discrete patient process steps including patient transport, selection and treatment delivery in patients treated in the SWIFT PRIME trial. Design, Setting, and Participants: Data was analyzed from the SWIFT PRIME trial, a global, multi-center, prospective, randomized, open, blinded endpoint (PROBE) IDE study comparing the functional outcomes in AIS subjects treated with either IV t-PA alone or IV t-PA in combination with Solitaire device. The trial enrolled 196 patients between Dec 2012 and Nov 2014. Patients were equally randomized to 98 in control and 98 in intervention arm. Each patient enrollment was analyzed for workflow and direct feedback was provided to the enrolling site. Main Outcomes and Measures: Analysis of relationship between time from onset to reperfusion and outcome; time from imaging to reperfusion (in the mother ship patients) and outcome. Analysis of time intervals of discrete steps in patient workflow. Results: In the treatment arm, onset to reperfusion treatment time of 150 minutes lead to 87% estimated probability of good outcome which decreased by 10% with every 60 minute delay. . The median time from Emergency Department (ED) arrival to groin access was 90 minutes (interquartile range [IQR] , 69 -120) and ED arrival to reperfusion time was 139 minutes (IQR, 108 -169). In all patients, the median ED to imaging start time was 16 minutes (IQR, 10-23.5), imaging start to qualifying image time was 9 minutes (5-19.5) and qualifying image to randomization was 30 minutes (IQR, . In the patients undergoing endovascular therapy, randomization to puncture time interval was 22 minutes (IQR, 12-32), puncture to device deployment was 24 minutes (IQR, (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) , and deployment to reperfusion was 8 minutes (IQR, 5-23). Patients who initially arrived to a referring facility ('drip and ship' patients) had slightly faster rates of workflow once they arrived to the endovascular capable center compared to patients presenting directly to the endovascular capable center ('mothership' patients) but the 'drip and ship' patients had significant overall delays in treatment as compared to 'mothership' patients (onset to puncture-time, 179.5 minutes versus 275 minutes, p < 0.001). Puncture to device deployment interval was longer in patients with left sided lesions versus right sided lesions (32.5 vs 22 minutes, p = 0.046) and in patients with severe vessel tortuosity (29 vs 22 minutes, p=0.21). Conclusions and Relevance: Detailed attention to workflow with iterative feedback and aggressive time goals leads to highly efficient workflow. This study was performed across 39 centers and 7 countries and supports the generalizability of rapid workflow implementation. Future steps for improvement include faster triage and transport of patients to endovascular capable centers as well as advancements in treating patients with difficult anatomical features.

Thomas Anderson (Sweden)

In the recently published randomized controlled studies on intravenous thrombolysis followed by thrombectomy against thrombectomy alone (MR CLEAN, ESCAPE, EXTEND-IA, SWIFT-PRIME and REVASCAT), stent retrievers were steadily utilized. In conclusion, these studies all showed superiority on stroke patient outcome by adding endovascular treatment with stent retrievers in the treatment of large vessel occlusions. Still, many controversies remain regarding both patient selection and the optimal technique. Which imaging modality is the best for properly selecting the patients that would benefit from the treatment? What is important in the pre-and posttreatment care of the thrombectomy patients? Which technique is to be preferred in the actual treatment? In this presentation, these issues will be discussed with special focus on problems with different selection methods, general anaesthesia versus conscious sedation, the use of balloon guide catheters and intermediate catheters as well as on special occasions that require specific technical considerations like tandem occlusions and acute dissections. Finally, a brief discussion will be initiated regarding the importance of clot composition for the technical considerations and the possibility to achieve a sufficient revascularization.

Swift decision making and recanalization is crucial in acute ischemic stroke treatment. The work flow from symptoms onset to recanalization has to be optimized outside and within the hospital; a challenge, taking into account the complexity of the rescue chain and the number of different professions involved. The most recent study results have shown great benefit of endovascular treatment in combination with intravenous thrombolysis compared to sole intravenous thrombolysis the for proximal vessel occlusions. Under this new light of endovascular stroke treatment regime, a few periprocedural aspects seem to have major impact on either time span to recanalization, clinical outcome after treatment, or both. Namely the role imaging (CT vs. MRI) and imaging protocols (CTA, CTP/MRA, MRP), the application of conscious sedation versus general anesthesia during intervention and the use of additional protection devices (guide catheter vs. balloon occlusion catheter vs. distal aspiration) is discussed. Despite the lack of randomized controlled trial focusing on these questions, the available data illustrates the pathway for an individualized decision making as well as an generally optimized workflow.

Endovascular management of acute ischemic stroke started with superselective intraarterial injections of thrombolytic drugs, first Streptokinase, later Urokinase, However, since the intracranial vessels are difficult to access, it wasn't feasible until a new microcatheter with different softness, the Tracker appeared on the market in the late 80-ies.

In 1991, the electrically detachable coils were introduced in the endovascular treatment of cerebral aneurysms. One of the methods major complications, the intraarterial clotting could be readily diagnosed in the hyperacute phase, and interventional neuroradiologists tried to utilize mechanical devices like different snares, microguidewires or balloons to retrieve, degrade or compress the clot. The first mechanical device, the Merci, specifically developed to retrieve the clot, was introduced 2001. The first stentriever (= stent-retriever), the Solitaire, reached the market 2006. Since then, many new devices with similar design have been introduced, but none of them has changed the paradigm, like the ADAPT, that was described in April 2013, and consists of the following steps: 1. A 6 Fr. long sheath is placed as high as possible without provoking vasospasm in the ICA or VA. 2. A large ID aspiration catheter ( 5MAX/5MAX ACE) is navigated over a long microcatheter up to the level of the clot. 3. Aspiration with the large bore catheter and the Penumbra aspiration pump is applied for at least 90 seconds. 4. The aspiration catheter is slowly removed and the vessel's patency is evaluated by angiography The author's experience with this technique will be presented. 11.00-13.00 Advanced Imaging S18.1 Pediatric vascular malformation: EV treatment

Over the last 35 years a major evolution, if not a true revolution has occurred in our understanding the various types of intracranial vascular malformations, coupled with our exponential technical advances in treating them has opened the emerging field of "Pediatric INR". We will present and described the various type lesions, and the various EV techniques.

We will review Vein of Galen malformations. Pial AVMs. Dural AVFs, as the main lesions, and we will review the various access techniques, and embolic agents presently used.

Since 2008 our neuroendovascular team has performed intra-arterial chemotherapy (IAC) in the hope of salvaging more eyes with retinoblastoma, the most common primary intraocular malignancy in children. 97 pediatric patients (106 eyes with retinoblastoma) have been treated with melphalan alone or in association with topotecan (follow-up range 6-82 months). On the whole, we carried out 431 sessions of IAC, 362 (84%) through the ophthalmic artery (OA) and 69 (16%) via external carotid artery (ECA). Each patient underwent from 3 to 6 sessions. 9 patients affected bilaterally were treated in the same session. No major neuroendovascular periprocedural complications occurred. The most frequent local permanent complications were chorioretinal atrophies (in 7 eyes). 66% of eyes did not undergo enucleation. Tumor remission was achieved in 60,3% of eyes.

In our seven-year experience IAC has demonstrated to be a safe and feasible procedure. Better results are obtained when associated with other focal therapies. Infusion from OA is not always possible or there is inadequate flow for a variety of functional and anatomic reasons, i.e intraorbital anastomoses connecting the OA and ECA. In such cases, the hemodynamic balance between the OA and the ECA may be subtle. Even when previous catheterization of the OA has been successful, subsequent attempts to achieve an acceptable choroidal blush may fail secondary to a series of factors, including vasospasm or momentary unbalances of the local hemodynamic. We also demonstrated that different patterns of drug delivery did not determine a significant change in the clinical outcome nor in ocular complications.

According to the ISSVA classificacion the superficial vascular malformations are divided in vascular tumors (childhood emangiomas) and vascular malformations. The latter may be low flow (venous, lymphatic, capillary or mixed forms) or of high flow, represented by arteriovenous malformations and arteriovenous fistulas. The role of embolization in these injuries can be curative as in the case of certain low-flow malformations and certain arteriovenous malformations and fistulas; palliative as in the case of giant defects without surgical indication or radiotherapy; and finally complementary to other treatments such as laser therapy, radiosurgery or surgery. Embolization of low flow malformation and a big part of the high flow ones are nowaday performed by direct puncture access. This thecnique allows to reach more easily the malformation core in low flow and arteriovenous communication area. Endovascular navigation, in not accessible malformation by direct puncture, can be associated. About literature data on relapse or progressive aggressiveness of facial AVM, we think that although this concept is valid in a minority of cases actually in the majority of S18.4 Endovascular treatment of head and neck vascular lesions

During this presentation will review the various vascular lesions of the head and neck, and the various endovascular treatments. Purpose: Cerebral venous thrombosis (CVT) is a diagnostic challenge due to non-specific clinical and radiological symptoms. The first imaging modality is usually emergency brain CT. The purpose of the study was to retrospectively analyze emergency brain CT examinations in CVT cases and look for pitfalls. Methods: Emergency brain CT of 18 patients with CVT confirmed either in CTA, MRI or DSA were retrospectively analyzed. The study group consisted of 12 women and 6 men (mean age 37.9 yrs). The clinical symptoms were headache and seizures (12 cases), hemiparesis (4 cases) and loss of consciousness (2 cases). CVT causes were: oral contraceptives (3 women), hormonal infertility treatment (1 woman), cesarean section (1 woman), middle ear infection (2 children), nephrotic syndrome (2 subjects), advanced malignant disease (2 subjects), temporal bone fracture (1 subject) or unkown ( 5 cases). In 18 cases superficial CVT was diagnosed, in 2 cases additionally associated with deep venous thrombosis. Result: In 7 cases CVT was correctly diagnosed on the basis of CT showing hyperdense vessels and brain lesions in 4 cases and only hyperdense vessels in 3 cases. In 3 cases CT images were reported as normal due to very subtle radiological symptoms such as: hyperdense single cortical vein, hyperdense midline deep veins or subtle bilateral thalamic edema. In 6 cases hemorrhagic brain lesions due to CVT were misinterpreted as different pathologies and the hyperdense vessels were overlooked. In these cases bleeding vascular malformation, hemorrhagic brain tumors (2 cases), brain contusion and non-specific unequivocal lesions (2 cases) were reported. In 2 patients with pathologies of the temporal bone (middle ear infection and fracture) and no brain lesions CVT was not diagnosed during the first CT. Conclusion: CVT is underdiagnosed in the emergency brain CT. Clinical and radiological correlation with detailed CT image analysis is crucial especially in young patients with hemorrhagic lesions and non-specific clinical symptoms. cerebral venous thrombosis,emergency brain CT,pitfalls Conclusion: CJD exists in three forms: sporadic, hereditary and iatrogenic.It is rapidly progressive, characterized by dementia and always fatal. There is no single diagnostic test for CJD. Computerized tomography of the brain can help exclude stroke or brain tumor in emergency cases . MRI can reveal typical brain signal intensity abnormalities that can help diagnose CJD, and it is compulsory to use DWI with ADC map and FLAIR sequences in the protocol. The only way to confirm a diagnosis of CJD is by brain biopsy or autopsy. Purpose: Describe immediate intracranial complications seen on MRI after carotid stenting procedure and find potential associations with preprocedural brain MRI findings and carotid plaque characteristics. Methods: 22 patients with symptomatic internal carotid artery (ICA) stenosis were included. They were treated within the next 5 days of the acute event with stent with distal embolic protection and double antiplatelet therapy. Preprocedural Doppler and gray scale US of carotid stenosis were performed in all the patients. Plaques were classified in 4 groups based on echogenicity.

Brain MRI pre and post-procedural were performed in all of them within the previous and next 5 days. Complications were described.

Result: 22 patients were studied, 17 men and 5 women, average age 69.7 years (SD 11.04). Degree of carotid stenosis seen by pre-procedural Doppler was severe in 19 patients (86.5%), and moderate in 2 (9%). One patient had a thrombosed previous stent. The type of carotid plaques defined by US were heterogeneous 11 (50%), calcified 4 (18%), hypoechoic 5 (23%) and hyperechoic 2 (9%). Pre-stenting brain MRI showed that most patients had focal white matter lesions classified as grade I in 45%, and grade II in 27% (Fazekas scale). Only 2 (9%) patients had microbleeds, 12 (54.5%) patients showed chronic infarctions, and 19 (86%) patients showed acute minor infarction. Brain MRI findings after carotid stenting: Three patients developed territorial infarcts, two of them associated with heterogeneous carotid plaque on US, and the other one, which showed petechial hemorrhagic transformation, associated with hypoechoic plaque. Two patients showed parenchymal hemorrhage, one associated with heterogeneous carotid plaque and the other with hypoechoic plaque, which also presented signs of cerebral hyperperfusion. Eleven (50%) patients had cerebral microinfarcts in distal vascular territories of the affected carotid artery. Conclusion: Carotid stenting for symptomatic ICA stenosis was demonstrated to be a safe procedure in several past studies. However, in our experience, cerebral microinfarcts are frequently found finding after carotid stenting procedure but with no apparent clinical impact. Others MRI findings of major clinical importance were significantly small and include petechial hemorrhagic transformation, brain hematoma and cerebral hyperperfusion, which might have an association with the carotid plaque characteristics.

Carotid stenting,symptomatic carotid stenosis,minor stroke

W.Y. Yu 1 , C. Trivedi 1 , W. Lee 1 , Y.Y. Sitoh 1 1 National Neuroscience Institute, Singapore, SINGAPORE Purpose: Prior studies have suggested that in patients with acute ischemic stroke, vessel recanalization by intravenous thrombolysis alone is unlikely to succeed when the intravascular thrombus length is beyond 8 mm, and these patients may benefit from intra-arterial mechanical thrombectomy. In the case selection for patients that may benefit from such procedures, rapid, non-invasive imaging using CT or MRI to measure intravascular thrombus is desirable.

Methods: We retrospectively studied 10 patients with acute ischemic stroke who underwent initial assessment with CT or MRI, followed by digital subtraction angiography (DSA) and intra-arterial mechanical thrombolysis within the same day. Two non-blinded radiologists reviewed all non-enhanced CT (NECT)/CT angiography ( Purpose: Cerebrovascular accidents involving small vessel disease is common in Asia. Dual energy unenhanced CT brain with monochromatic reconstruction can provide superior image quality for the detection of acute pathology from small vessel disease by depiction of the subtle differences in contrast density. Methods: Patients referred for unenhanced CT brain study to exclude acute pathology were scanned on a 128 slice dual energy CT scanner with gemstone spectral imaging and adaptive statistical iterative reconstruction algorithm for radiation dose savings. Images were reconstructed at different monochromatic levels ranging from 40 to 70 keV levels. The scans were assessed independently by 2 experienced neuroradiologists for image quality and detection of small vessel disease with acute pathology, consensus readings were made when there were differences in opinion. Subsequent imaging and clinical final diagnosis was used as the reference standard. Result: There were 43 patients scanned. Images at the lower 40keV level had superior contrast to noise ratio (CNR) but were impaired by poor signal to noise ratio (SNR). Images at 50 keV and 70 keV were generally comparable for image quality, with 50 keV superior for depiction of subtle differences in CNR in acute small vessel pathology. Conclusion: Dual energy unenhanced CT brain with monochromatic reconstruction at 50 keV maximises image quality for the depiction of small vessel disease. Purpose: The purposes of this study are to evaluate the depiction of brain ischemic stroke by using double inversion recovery (DIR) to compare the lesion-to-normal ratio (LNR) of DIR with that of diffusion-weighted images (DWI) and fluid-attenuated inversion recovery (FLAIR) images. Methods: Seventy five patients underwent the MRI scans with FLAIR, DWI with b-value of zero (T2WI) and 1000 s/cm2 (DWI), and DIR sequences within 96 hours of onset. To obtain signals, two regions-of-interest were set in an infarction lesion (L) and a contralateral normal area (N) for each patient. The lesion-to-normal ratio (LNR), defined as LNR= 100(L-N)/N, was calculated for each sequence including the apparent diffusion coefficient (ADC). Patients were categorized into five groups according to the symptom onset time, which were Group I (onset less than 3 hours), Group II (onset more than 3 hours but less than 6 hours), Group III (onset more than 6 hours but less than 24 hours), Group IV (onset more than 24 hours but less than 48 hours), and Group V (onset more than 48 hours but less than 96 hours). To find effects of LNRs among imaging sequences in each group, , Friedman test was performed followed by post-hoc analysis. Purpose: Purpose: Neurodevelopmental outcome of children is a very serius issue which causes anxiety and inconvenience to parents of children who presented with cerebral infarction the first days of birth. We studied the neurodevelopmental outcome of children with cerebral infarct in relation to localization of the brain lesion. Methods: Methods: Our study includes three cases of children who were born with caesarian section and presented with clonic seizures during the first days of life. All of them underwent a brain MRI scan which revealed the presence of ischemic lesions at brain regions of middle cerebral distribution. They were also assessed for neurocognitive and neurodevelopmental disorders. Result: Results: Brain MRI scans demonstrated: a) for the first newborn a recent ischemic lesion at the isle of Reil which is perfused from the right middle cerebral artery, b) for the second one acute ischemic infarct of the left thalamus, lenticular nucleus and isle of Reil, and c) for the last one cortical and subcortical infarct at the area of the left parietal lobe. Despite the severity of the brain lesions neurocognitive and behavioral assessment was normal in all cases. Conclusion: Conclusions: In our series the neurodevelopmental assessment of the children with infract in the distribution area of middle cerebral artery showed no neurodevelopmental impairment. This means that not all the cerebral infarcts have adverse effects on the brain development and cognitive function of the children and therefore counseling of the parents should be based on the exact involved anatomic area of the brain and not on the insult itself. NEONATAL STROKE,SEIZURES,NEURODEVELOPMENTAL OUTCOME Purpose: To evaluate the use of diluted iodinated contrast agents with normal saline or blood on magnetic resonance imaging (MRI), especially T1-weighted images (T1WIs), T2WIs, and gradient echo (GRE) images, for distinguishing contrast staining from a hyperacute hemorrhage, which could occur after transarterial thrombolysis in acute stroke patients. Methods: On 3.0T MRI, T1WIs, T2WIs, and GRE images were scanned using a phantom with five different kinds of diluted nonionic iodinated contrast agents at different concentrations (0, 0.1, 0.4, 0.6, 1.2, 2, and 2.4 M I mole/L). The contrast agents were diluted with normal saline or venous blood sampled within 6 h. We compared the signal intensity (SI) of the phantom visually and quantitatively calculated the T1-and T2relaxation times. Result: The iodinated contrast agents had a T1-and T2-shortening effect. With increases in the concentration of the contrast agents, the effect of T1 and T2 shortening became more prominent. The T2shortening effect of the iodinated contrast agents was much weaker than that of venous blood. Although the SI of diluted iodinated contrast agents with normal saline was intermediate on GRE images, the SI of blood with/without iodinated contrast agents was dark on GRE images. Conclusion: On 3.0T MRI, the SI of iodinated contrast agents diluted with normal saline was different to that of blood or blood with contrast agent on T2WIs and GRE sequences.

Purpose: Large proportion of post-stroke patients has to deal with problems in walking. To specify the neuroanatomical correlation of walking ability in patients with stroke is important. We therefore aimed to reveal the correlation with the lesion location from MRI and walking ability at 3 months from attack Methods: 374 patients with first onset acute stroke (within 7 days after onset) were enrolled and took the MRI who visited the Severance hospital from August 2012 to December 2013. Brain MRI scans included fluid attenuated inversion recovery (FLAIR) and diffusion images obtained with standard parameter on a 3.0T Philips intera scanner, First, region of interest (ROI) surrounding the diffusion image lesion was drawn manually with a generous margin at each affected slice, using MRIcro software. The accuracy of lesion delineation was inspected visually at each slice, and the corresponding FLAIR was checked for confirming plausibility and extent of infarct ROI. Second, it was transformed to the standard brain MRI template using Statistical Parametric Mapping 8 (SPM8) running under Matlab. The normalized lesion images were used as ROI for subsequent analysis in MRIcro and voxel-based statistical analysis. We examined walking ability measured by the FAC score(0-5) after 3 months and the patients were divided into two groups according to their independent walking ability at 3 months; the ambulatory group(FAC 3,4,5) and the nonambulatory group.(FAC 0,1,2), and then compare the lesion in the ambulatory and non-ambulatory group, using voxel by voxel chi square statistics. Purpose: Bilateral thalamic infarcts are rare presentations of stroke. They are the result of a complex combination of risk factors and a predisposing vessel distribution. Such infarcts are seen almost exclusively in the setting of vascular anomalies where a single artery supplies both sides of the brain. The occlusion of a rare arterial variant called the artery of Percheron(AOP) results in bilateral thalamic infarcts, with or without midbrain involvement. Methods: A 30-year-old man was admitted in Military Medical Academy in Belgrade, one day after experiencing occipital headache,decrease of consiousness and visual disturbance. The patient had no past medical history.On admission day his symptoms improved and the only abnormality on the physical and complete neurological examination was confusion.Initial brain CT performed in regional hospital was normal.

The day after admittance we performed brain MSCT with MSCT angiography,and two days later MRI of the brain .Follow-up MRI was performed six weeks later. Result: Brain MSCT showed bilateral thalamic hipodensities more prominent on the left side consistent with acute ischemic stroke.MSCT angiography showed patent posterior arterial circulation , including the tip of the basilar artery and both posterior cerebral arteries, as well as deep venous system( internal cerebral veins, Vein of Galen and streight sinus), making the case compatible with occlusion of the artery of Percheron. MRI of the brain showed bilateral thalamic areas of low signal intensities on fast spin echo T1weighted and high signal intensity on fast spin-echo T2 weighted and FLAIR images. At the same level, restricted diffusion on diffusion weighted images(DWI), was confirmed on the apparent diffusion coefficient (ADC)maps , suggestive of acute ischemic injury.Follow up MRI showed tipical ischemic stroke evolution. Conclusion: Bilateral thalamic infarction represents a relatively rare stroke syndrome and presents with varying symptoms. The anatomic etiology is presumed to be the occlusion of Percheron artery, an uncommon vascular variation. The AOP is rarely visualized, even with conventional angiography, because it is too small. However, this can be utilized to roll out the involvement of larger vessels. This type of infarct has a favorable prognosis, although some patients experience persistent visual field deficits. Purpose: The superiority of the newer generation of endovascular devices over previous devices is well established. However it is important to update evaluations of the technical efficacy of these devices including quality of recanalization and the number and nature of complications from the procedure. The current study provides a detailed analysis of the catheter angiographic outcomes using the Solitaire revascularization device within the endovascular arm of a multicenter, international, randomized trial. Methods: The SWIFT PRIME trial is an RCT comparing IVtPA versus IVtPA + endovascular treatment using the Solitaire FR or Solitaire 2 devices. The trial was put on hold after enrollment of 196 patients over 39 sites by the DSMB. Use of suction either through a balloon guide catheter or through a distal access catheter in conjuction with the Solitaire device was recommended. All angiographic images were centrally adjudicated by a core lab regarding quality of reperfusion (TICI scale), quality of recanalization (AOL scale), and presence of angiographic complications. The number and size of device deployments was documented. Presence of intracranial hemorrhage subsequent to the procedure was documented and whether this was likely due to a complication from the angiographic procedure was centrally adjudicated by two experts. Result: Shall be presented at the meeting. Conclusion: The findings will provide insight into the technical success and complication rate of Solitaire FR device for endovascular treatment of stroke in multiple centers in the United States and Europe. The indications for CAS were symptomatic carotid-artery stenosis 60% and asymptomatic stenosis of at least 80%. There were 74 men and 22 women and their age range was 50-79 years (mean 71.1). Self expanding stents with cerebral protection devices were used in all cases. Acetylsalicylic acid (100mg/d) and clopidogrel (75mg/d) were applied for at least 4 to 5 days prior to procedure. Weight-adjusted (70U/kg) heparin was used. Atropine (1mg) was given intravenously, if needed, to reduce bradycardia and hypotension potentially associated with carotid dilation. Acetylsalicylic acid (100mg/d) and clopidogrel (75mg/d) was continued for 3 months after the interventional procedure. Mono antiplatelet therapy (aspirin, clopidogrel, or ticlopidine) was continued indefinitely. One hundred six stents (56 Protégé, 37 Precise stent, 12 Wallstent, and 2 Acculink) and distal filters (94 Spider Rx, 9 Filter-wire, 3 Embo-shield) were used.

Result: There were one death (huge ICH), 4 minor strokes (3.7%), 9 bradycardia (8.4%), and 3 groin hematoma(2.8%)as peri-procedural complications. Follow-up angiography was done in 78 patients (73.5%) for 6-58 months (mean 17.3), there was only one restenosis (0.9%). Clinical follow-up was done for 94 patients (88.6%) for 6-60 months (mean 32), there were two deaths (1.8%), one myocardial infarction, one rectal cancer, one major stroke (basilar artery, 21 months), and one minor stroke (cerebellum, 10 months). Conclusion: CAS is and effective treatment modality and as safe as CEA for carefully selected patients. Judicious selection of the procedure is made on a case-by-case after considering the patient (physiological), lesion, and access (anatomical) factors that increase the risk of CAS and CEA in that particular patient.

ischemic stroke,carotid artery,stent Purpose: Cerebrovascular disease complicated with coronary, aortic, or peripheral artery disorder has a high incidence rate. The optimal management of these patients remains unclear. Methods: We retrospectively studied 7 patients (5 men, 2 women, mean age, 74.1 years) with concomitant coronary, aortic, or peripheral artery disorder and cerebrovascular disease, treated between 2011 and 2014 at two hospitals. Result: None of the patients underwent simultaneous treatments. Three underwent carotid artery stenting (CAS) followed by coronary artery bypass grafting, femoral arterypopliteal artery bypass, and aortic aneurysmal repair (AAR). Furthermore, two underwent percutaneous coronary intervention (PCI) followed by carotid endarterectomy, one underwent PCI followed by extracranial arteryintracranial artery bypass surgery (EC-IC BS), and one underwent EC-IC BS followed by AAR. The mean interstage interval of these seven cases was 2.4 months. There were no major adverse events (MAE) in the interstage interval of these or cerebrovascular treatments. One patient treated with EC-IC BS followed by AAR died due to major cerebral infarction after AAR. Conclusion: There were no MAE in the interstage interval of these treatments, and there were relatively few MAE in the perioperative period. MAE can lead to fatal complications, and therefore we should carefully consider the indications and sequence of treatments through multidisciplinary discussion. As it is unnecessary to discontinue antiplatelet therapy and have long interstage interval, a neuroendovascular approach may be preferable in patients in whom PCI is not an option. Pathophysiological mechanism is vasoconstriction which leads to reduced brain perfusion and result is vasogenic edema. Mortality rate is up to 15% of cases due to complications as acute hemorrhage and ischemia. Methods: 73-year-old men was admitted in Stroke hospital Sveti Sava in Belgrade with symptoms of headache, instability, loss of balance and discreet left sided hemiparesis. The symptoms started five days before admittance. He had a history of hypertension and chronic renal insufficiency. We performed brain MSCT, MRI of brain with contrast, MR angiography and MRI spectroscopy. Result: Brain MSCT showed the presence of bilateral frontal and parietal patchy hypodense foci, more prominent on the right and in subcortically region. MRI scanning showed cortico-subcortical temporopolar, parieto-occipital, posteriorparietal and frontal bilateral lesions more dominant on the right. Those lesions were hyperintense in T2W /FLAIR sequence with mild compressive effect on occipital horn and body of the right lateral ventricle. There was no postcontrast enhancement of lesions. On DWI sequence there were no changes in signal intensity, but on ADC map hyperintensity of the signal was observed in parieto-occipital and frontal regions bilaterally. That implicated the existence of vasogenic edema and suggested PRES. MR angiography was normal. Using 2D multivoxel spectroscopy the obtained spectra showed slightly higher values of choline and creatine (Cho/Cr), and NAA was mildly decreased. After diagnosing the patient was regularly treated with antihypertensive, antilypemic and rehydration therapy and was discharged two weeks later with normalized neurological findings. Follow up MR scanning, two months after the initial one, showed complete regression of T2W/FLAIR hyperintense changes which had previously affected cortex and subcortical white matter. Conclusion: Until recently it was thought that PRES tipically affects bilaterally and simetrically white matter, predominantly in occipital and posterior parietal areas. Less frequent, changes were described as asymmetric, involving frontal and temporal lobes, basal ganglia and cortical grey matter. Magnetic resonance scanning is crucial for diagnosing, monitoring and assessing the treatment effectiveness of this syndrome. Purpose: The purpose of this study was to determine the relationship between clinical response with and without computed tomography perfusion (CTP) mismatch in stroke patients. Methods: We retrospectively reviewed 130 patients presenting with hyperacute stroke within the first 6 hours after symptom onset, in Stroke hospital Sveti Sava in Belgrade, from March 2010 to March 2015. All patients on admission underwent multimodal cerebrovascular computed tomography (CT) imaging protocols, including parenchymal imaging-noncontrast head CT, vascular imaging-CT angiography and penumbral imaging-CTP. One hundred patients from experimental group were treated with intravenous tissue plasminogen activator (rtPA) and thirty patients from control group were not treated with rtPA. Mismatch was defined as a perfusion lesion (CBF lesion) > 20% larger than the core lesion (CBV). CTP was used to categorize patients into Mismatch versus Absence of mismatch subgroup. Good clinical outcome was defined by improvement of NIHSS > 3 points, and excellent outcome was defined as reduction in NIHSS > 7 points at day 30. CT perfusion,acute stroke,mismatch Purpose: Efficacy and safety of Solitaire stent thrombectomy in acute occlusion of intracranial artery has been proved in many previous studies. However, most of these studies were focused on occlusion of proximal vessels such as distal ICA (T-segment), M1 segment of middle cerebral artery (MCA), or basilar artery (BA), and there are not many studies about usefulness of Solitaire stent in small intracranial vessel occlusion such as M2 segment occlusion. Therefore, our study aimed to retrospectively assess the efficacy and safety of mechanical thrombectomy using Solitaire stent in patients with small vessel occlusion (M2 segment of MCA). Methods: We conducted a retrospective review of 28 patients who underwent Solitaire stent thrombectomy for treatment of M2 occlusion between November 2014 and March 2014. We evaluated immediate angiographic results and clinical outcomes through reviewing of patient's electrical medical records. Result: The ratio of patients' sex was 1: 1 (man = 14, women = 14) and mean age was 71. 32 (range, 51 -84). The rate of successful recanalization (TICI grade > 2b) was 71.43% (20/28). Among these 20 patients, 16 patients were treated with Solitaire thrombectomy as the single treatment technique and 4 patients were treated in combination with urokinase. Mean initial NIHSS score was 12.80 (range, 2-21) and was 8.24 (range, 0-30) at discharge. Favorable clinical outcomes (mRS score at 3 months < 2) were seen in 17 patients out of 28 (60.71%). Migration of tiny emboli was observed in 2 (7.14 %) but 1 of them presented no neurologic symptom (mRS score at 3 months = 0). Post-procedural symptomatic intracerebral hemorrhage has occurred in 1 patient (3.57 %). Conclusion: Mechanical thrombectomy using Solitaire stent appears to be safe and is capable of achieving high rate of successful recanalization and favorable clinical outcomes in patients with distal cerebral vessel occlusion (M2). Acute stroke,Thrombolysis,Angiography Purpose: Background: The importance of 'time is brain' is well known. Rapid workflow targets were established for the SWIFT PRIME trial. Targets for time from acquisition of qualifying parenchymal imaging to groin puncture were: optimalwithin 70 minutes, acceptablewithin 90 minutes. Targets for time from groin puncture to reperfusion were optimalwithin 20 minutes, acceptablewithin 30 minutes. This study provides a detailed analysis of this workflow within the endovascular arm of the trial. . Methods: Methods: The details of the SWIFT PRIME trial have been previously described. The process of ensuring and improving workflow efficiency in the endovascular arm was based on the following: 1. Site selection: only those sites were chosen to participate who could successfully demonstrate CT head to recanalization in < 90 minutes in at least 5 patients. 2. Extensive training in workflow including teamwork and parallel proces

The data will be analyzed for the following: Purpose: Agenesis, aplasia, and hypoplasia of the internal carotid artery (ICA) are rare congenital anomalies, occurring in less than 0.01% of the population. ICA agenesis was first described in 1787, after a postmortem examination of a patient and there are approximately only 100 cases reported in the literature. When a unilateral ICA is absent, collateral circulation can be sufficient to maintain cerebral function with few or no neurologic symptoms.The purpose of this work is to describe a very rare case, as it is the internal carotid artery agenesis. Methods: We report a case of a 46 years old woman who was evaluated in our department for bilateral action tremor. A Magnetic Resonance (MR) and a computed tomography (CT) were performed. Result: The MR showed agenesis of the right ICA, clinically asymptomatic. Further investigation with CT confirmed the absence of the right carotid canal. The vascular supply of the anterior cerebral hemisphere was possible due to collateral circulation via Circle of Willis and no parenchymal abnormalities were seen on MR. Conclusion: The term absence has been chosen to incorporate agenesis, aplasia, and hypoplasia of the ICA. Agenesis is defined as complete failure of an organ to develop, aplasia as lack of development (but its precursor did exist at one time), and hypoplasia as incomplete development of the organ. Although an exact cause of these developmental anomalies has not been established, all three variations are thought to represent the sequela from an insult to the developing embryo.

Most patients with ICA agenesis present with focal neurologic signs, such as convulsions, headache, or transient ischemic attack, and ICA agenesis may be associated with aneurysm, hemorrhage, cerebral hypoplasia, hemangioma, anomalous vascular anastomosis and rarely Horner`s Syndrome. However they can be asymptomatic and it can be only an incidental finding as it was in our case.

J. Amorim 1 , J. Jacinto 2 , M. Rita 2 , I. Fragata 2 , J. Reis 2 1 Hospital de Braga -Neuroradiology Department, Braga, PORTUGAL, 2 Hospital de São José -Neuroradiology Department, Lisboa, PORTUGAL Purpose: In acute intracranial arterial occlusion with sudden neurologic deficit, limited time is available to obtain information for carefully directed treatment. CT angiography (CTA) is commonly used in most stroke centres to obtain information on the clot location and presence of collaterals. This data can influence treatment decision and clinical outcome in the setting of acute ischemic stroke. CTA is a static technique, that gives little information on the flow direction of collaterals. Transcranial Doppler and digital subtraction angiography (DSA) complement CTA and provide dynamic information on collateral circulation and flow direction in the circle of Willis. Methods: A 55-year-old man, previously asymptomatic, was assessed in the emergency room with a history of aphasia, right sided hemiparesis and sensory loss lasting for one hour. CT scan upon arrival revealed the presence of an hyperdense Middle Cerebral Artery (MCA) (superior M2 division), with no apparent acute ischemic lesions. CTA was performed showing a severe stenosis of the distal cervical segment of the left ICA. A strong hyperattenuation of the ICA, immediately after the stenosis and extending to the supraclinoid segment was found and could not be explained. Both MCAs showed symmetric density and a left M2 occlusion was confirmed. DSA confirmed occlusion of the left superior division of M2, and the severe cervical stenosis was in fact a dissection of the ICA. Collateral perfusion of the left MCA was done through the anterior communicating artery, with no significant circulatory delay.

Result: CTA finding of a hyperattenuating segment of the ICA in this patient was better understood after DSA, and reflected two phenomena:

(1) a severe cervical ICA stenosis, and (2) presence of collateral flow coming from the anterior communicating artery, washing out the contrast from the distal ICA and leaving a "sequestered" segment with no signs of clot formation. This sign was most probably related to contrast stasis and to a longer acquisition time of the CTA. Purpose: Correct evaluation of the degree of carotid stenosis in DSA is a crucial factor when deciding for revascularization treatment. We sought to compare the accuracy of "naked eye" assessment of the degree of carotid stenosis by an experienced neurointerventionalist, a neuroradiology resident and a stroke unit physician, with the calculated NASCET score. Methods: We reviewed our institution imaging archive and chose forty cases of suspected carotid stenosis. Standard PA and lateral projection DSA images were presented to an experienced neurointerventionalist, a neuroradiology resident (4th year) and a stroke unit physician for them to estimate the degree of internal carotid artery (ICA) stenosis. The NASCET score was calculated for each ICA in the angio suite workstation. Observers were blinded to the NASCET score results. Interobserver agreement was analyzed with Pearson correlation coefficient and kappa statistic. Result: Forty carotid bifurcations were studied. Stenosis degree ranged from 0% to total occlusion. Interobserver correlation coefficients ranged from 0,866 to 0,950. Correlation of eye estimation with NASCET measurements was high (from 0,878 to 0,950), being highest with both neuroradiologist observers. Interobserver agreement was slight to fair (kappa ranged from 0,166 to 0,33). Interobserver agreement was higher for high grade stenosis (>70%) especially between consultant and resident (kappa 0,510). There was total agreement for occlusions between the three observers. Seven significant discrepancies were identified, all of which were overestimation of low grade stenosis. The consultant had the lower number of discrepancies (only two). One external carotid stenosis was mistaken for the internal carotid by the stroke physician. Purpose: Tentorial artery arises from the dorsal aspect of the cavernous portion of the internal carotid artery. This vessel often play role as the feeder of dural arteriovenous fistulae or skull base brain tumors. Embolization from tentorial artery is rarely required for curative or palliative transarterial embolization for shunt disease, or preoperative embolization with subsequent tumor removal. We report technical tips and potential risks of transarterial embolization using n-butyl cyanoacrylate from tentorial artery. Methods: Between 2009 and 2014, 3 patients were treated by transarterial embolization using n-butyl cyanoacrylate from tentorial artery under general anesthesia. The etiologies consisted of two tentorial dural arteriovenous fistulae and a cavernous sinus dural arteriovenous fistula. Mean follow-up period of three cases was 7 months, 14 months and 37 months. Result: In all patients, superselective catheterization to tentorial artery was successfully achieved. Transarterial embolization was performed with n-butyl cyanoacrylate, ranged from 20% to 40% concentration. Balloon assist technique was applied for catheterization of the microcatheter by positioning the balloon just distal to the branch, and protection of the internal carotid artery from reflux of the glue by inflating the balloon at the orifice of the branch in all cases. Transient abducens palsy occurred in 1 case as a complication related to the procedure. N-butyl cyanoacrylate did not migrate into the internal carotid artery, therefore there were no ischemic complication associated with procedures. During the follow-up period we confirmed no recurrence of the shunt by cerebral angiography or 3-Tesla magnetic resonance angiography in all cases. Conclusion: Vascular network around the cavernous portion of internal carotid artery has many variations, and wedged glue injection causes the opening of undesirable vascular channel and the glue migration associated with significant complications, therefore a wedged position of the microcatheter should be avoided. As microcatheter tends to be wedged more easily in low flow feeders, particular attention should be paid in embolization of these feeders. A stable position of the microcatheter and a careful protection of the internal carotid artery using the balloon support may lead to effective embolization from tentorial artery. Purpose: We encountered a case of arteriovenous shunt of the trigeminal nerve root. This shunt was fed mainly by a branch from basilar artery, and also by right caroticotympanic artery. In the literature this type of lesions were described as "arteriovenous malformation (AVM) of trigeminal nerve" in some cases, and "dural arteriovenous fistula (AVF) of Meckel's cave" in other cases. We discuss the etiology of this kind of lesions. Methods: Case: A 42 year-old male was referred to our hospital with suspicion of brain AVM, which was incidentally pointed out by MR. The patient was totally asymptomatic. The MRA revealed small arteriovenous shunt fed by a branch from basilar artery, draining into superior petrosal sinus. Angiography demonstrated that this shunt was also fed from right caroticotympanic artery. The main feeder was branching from upper third of bailar artery, above the AICA. It seemed to be a remnant of trigeminal artery. The nidus was confirmed to be within the nerve root of the trigeminal artery by the axial reconstruction of 3D angiography. Purpose: To find out if any changes of brain regions functional interaction take place in patients with cryptogenic temporal lobe epilepsy during seizure-free period. Methods: All 15 patients with CE (10 men, 5 women) and 15 healthy controls (HC) (10 men, 5 women) underwent MRI (incl. resting state fMRI) on 3,0T field strength MR system. Functional images were acquired using an echo planar imaging sequence aligned along the anterior commissure-posterior commissure line were acquired. In each session, a total of 80 volumes were collected, resulting in a total scan time of 480 s. For each patient, one or two sessions were acquired. Subjects were instructed simply to rest with their eyes closed, not to think of anything in particular, and not to fall asleep. Data were analysed using Matlab-based software (SPM12, CONN14 Purpose: Epilepsy is a common presenting or complicating feature of the neurocutaneous syndromes. This poster presentation will educate the reader in the spectrum of neuroimaging findings in a range of phakomatoses and develop an understanding of their association with epilepsy. We aim to provide a structure for the accurate diagnosis of neurocutaneous syndromes and to enhance the readers' appreciation of how neuroradiology can assist in the management of epilepsy in these conditions. Methods: We will review the current literature and illustrate cases from our own epilepsy surgery surveillance program. These include tuberous sclerosis, Sturge-Weber syndrome, neurofibromatosis type 1 and incontinentia pigmenti. Methods: We retrospectively reviewed clinical records and imaging studies of three patients who met diagnostic criteria for Leigh syndrome at our institute in the last 5 years. The age of the patients ranged from 9 months to 3 years at the time of diagnosis. Result: Two patients presented with motor and intellectual developmental delay. One of them also had seizures. Interestingly, the other patient presented with symmetrical flaccid paralysis and was previously diagnosed as acute inflammatory demyelinating polyradiculoneuropathy (AIDP). But SURF1 mutation was later identified in this patient. Elevated lactate was found in the serum of all patients and one cerebrospinal fluid (CSF) sample. MRI and MR spectroscopy were performed in all patients. Symmetrical hyperintense lesions on T2-weighted images were found at the subthalamic nuclei, brainstem, periaqueductal gray matter, dentate nuclei, and medulla in all patients. Two patients also had abnormalities at the basal ganglia. Some of these lesions showed restricted diffusion and variable enhancement. MR spectroscopy in 2 patients showed reduced N-acetylaspartate (NAA), elevated lactate and elevated choline. Conclusion: Symmetrical brainstem lesions in specific location with or without basal ganglia abnormalities in a child with neurological problems should prompt the clinician and radiologist to consider Leigh syndrome.

Leigh syndrome,SURF1,Brainstem lesions We study all the patients with T1-weighted image (T1WI) sequences in both axial and coronal planes, and T2-weighted short-tau inversion recovery (STIR) in axial plane in 1.5T Magnet. T1WI are used to evaluate the decrease in muscle volume and to show the signal changes from fat infiltration into muscle grading it according to the well-stablished rating scales. STIR helps in muscle edema detection. Result: We show some of the WB-MRI muscle patterns of patients with proven CM, CMD and LGMD, such as Nebulin (NEB), Ryanodine Receptor-1 (RYR1), Caveolin-3 (Cav3), Collagen-6 (Col6), Dynamin-2 (DNM2), Myotubularin-1 (MTM1), Titin (TTN), Selenoprotein N-1 (SEPN1), Four and a half LIM domains protein-1 (FHL1), Lamin A/C (LMNA), Laminin alpha-2 (LAMA2), and some LGMD, among others. We are able to show WB-MRI of patients from infancy to adulthood, their evolution and progression, trying to help in diagnosing these diseases in early stages for preventing further related complications. Furthermore, WB-MRI helps in targeting the appropriate muscle for biopsy. Conclusion: WB-MRI is of great value in providing useful additional information not only to target the most appropriate genetic investigations, but also to monitorize disease evolution in Neuromuscular Disorders. Therefore, this late-onset type is classified as a cardiac variant in the literature. The neurological involvement of this late-onset type is still unclear. The study was aimed to understand the brain MRI of this lateonset type. Methods: Two neuroradiologists retrospectively analyzed all brain MRI findings from IVS4 Fabry patients, the sex-age matched stroke patients and normal control (NC) group in our hospital. Result: 29 patients (18 males and 11 females) of IVS4 mutations, the sex-age matched stroke patients and normal control group underwent MRI at mean age of 55.3, 55.3 and 55.6 years, respectively. Infarction was found in 8 (28%) IVS4 Fabry patients, 29 (100%) in stroke patients, and 0(0%) in NC. The positive pulvinar sign were 6 (21%) in IVS4 Fabry patients, 0 (0%) in stroke patients, and 0 (0%) in NC group (p<0.05). No significant difference was found in the Fazekas scores among all groups. The basilar artery diameter was significantly higher in the stroke group, 2.90 (± 0.56) mm, but there was no difference between IVS4 group and other two groups. The height of basilar artery bifurcation were at the dorsum sellae, within suprasellar cisterns, at third ventricular floor for 6(21%), 10(34%), 13(45%) IVS4 patients; 4(14%), 20(69%), 4(14%) stroke patients; and 11(38%), 12(41%), 6(21%) normal control (p<0.05). Conclusion: Patients with late-onset Fabry disease presented with higher incidence of pulvinar sign than stroke and NC group. Purpose: Homocystinuria (HCU) due to cystathionine beta-synthase deficiency is a recessively inherited metabolic disease caused by an inborn error of the transsulfuration pathway of methionine metabolism. Untreated patients have a 30% risk of a thromboembolic event before the age of 20 years. The purpose of our study is: 1. To illustrate the abnormalities demonstrated on MRI brain in HCU patients with cerebrovascular complications. 2. To compare the frequency of such abnormalities in long-term treated patients with well-and poorly-controlled disease, as indicated by serum free homocystine (fHcy) and total homocysteine (tHcy) levels.

Methods: Twenty-two patients; 15 of whom were detected at newborn screening and 7 who were diagnosed later, with a total of 419 patient years of treatment underwent neurological examination and brain MRI with MRV. Image analysis was performed independently by two experienced neuroradiologists. Good biochemical control was as previously defined as a lifetime median free homocystine of 11 umol/L. Biochemical control of these patients during long-term treatment was calculated as lifetime median of fHcy for each patient. For each group, a mean is obtained from the lifetime medians of fHcy. Result: The mean age of the study group was 22.6 years (15-36) yrs. There were no reported neurological or radiological abnormalities in the 'newborn screened, good control' group. Ten patients in the 'newborn screened, poor control' and 'late-detected' groups combined had abnormal appearances consistent with microinfarcts on MRI. One of these patients had superior sagittal sinus thrombosis. Of the ten patients with radiological abnormalities 2 had cerebrovascular accidents and 7 had positive findings on neurological examination. Conclusion: MRI can be used to demonstrate the cause of stroke symptoms in HCU patients, as well as silent cerebrovascular disease in this cohort. Our study shows that radiological abnormalities are more common in patients with poor biochemical control. Brain imaging therefore has useful roles in the diagnosis of microinfarcts and/or cerebral venous sinus thrombosis in HCU patients presenting with stroke, in the detection of 'silent' cerebrovascular complications in poorly controlled disease, and also in reassurance of asymptomatic HCU patients who are at increased risk. Prasat Neurological Institute, Bangkok, THAILAND Purpose: Prasat Neurological Institute has been using the X-ray machine for more than 10 years.However,they are now worn-out and need to be replaced.Nowadays,medical technology exists in a variety of highly advance forms.Therefore,the decision to purchase an expensive medical equipments must concern about the benefit of patients along with an appropriate budget that need regard of technology assessment. The digital radiography system are classified into 2 main types, Digital Radiography (DR) and Computed Radiography(CR). The objective of this study is to compare the advantages and disadvatages between them to obtain and increase new knowledge in present and future. Methods: To gather knowledge,we search from academic journals in internet.We also make questionnaire to know satisfactory levels of users such as technologist in X-ray department of Ratwithi hospital and two other private hospital using digital radiography system. Result: After we have analyzed the information,the research shows that Digital Radiography system is better than Computed Radiography in the aspects of lower x-ray exposure to patients and better quality of X-ray image. The patients also receive faster and more convenient service. Purpose: Radiation exposure is inherent in neurovascular interventional radiology (IR). A potential exposure of 1 mSv has been suggested as a cutoff for provision of risk information, as it corresponds to a 1 in 10000 increased cancer risk. Informed consent requires disclosure of rare yet potentially significant risks, yet patient and non-radiologist physician knowledge of these risks is lacking. Neurovascular IR patient perception and knowledge of these risks remains unknown. The purpose of this study is to explore neurovascular IR patient perception of cancer-related radiation risk exposure and whether radiation consent is warranted. Methods: A multiple-choice survey was administered to 42 adult patients undergoing a non-emergent neurovascular IR procedure at a tertiary care centre. 67% of patients had previously undergone a neurovascular IR procedure. Statistical analysis of with Fisher Exact test was performed based on patient past neurovascular IR history (p<0.05).

Result: Almost all subjects (90%) wanted to be informed if the radiationrelated increased cancer risk was 1 in 100. Most (82%) wanted to be informed if the risk was moderate, 1 in 1000, or low, 1 in 10000 (70%). Only half of the patients were aware that they were exposed to radiation during their procedure, irrespective of previous neurovascular IR history. The majority (74%) believed that the ordering physician should be responsible for informing patients about radiation exposure. Most (85%) believed radiation consent should include radiation-related cancer risks, and that both verbal and written radiation consent should be obtained (74%). No significant difference was present based on past neurovascular IR history (p>0.05). Conclusion: Neurovascular IR patient awareness of radiation exposure is suboptimal. Based on this survey, most patients want to discuss cancerrelated radiation risks with the ordering physician in order to make informed decisions. This is potentially concerning as non-radiologist ordering physicians may not be as knowledgeable on radiation-related cancer risks. Neurointerventional radiologists should consider obtaining informed consent for procedures with anticipated doses of 1 mSv or greater. Overall, the rate of procedure-related complications was 6.4% (10/156). Follow-up angiography more than 1 year after the coil embolization was obtained in 42 patients with 43 aneurysms. Of these, recanalization was observed in 5 aneurysms (11.6%); 34 aneurysms (79.1%) unchanged; and 4 aneurysms (9.3%) showed progressive thrombosis. Conclusion: In our experience, removal and reposition of the Solitaire stent allowed for reducing thromboembolic complications and making the coiling procedure faster and easier in selected patients. Considering the good clinical outcome with the low rates of both procedural complication and recurrence, Solitaire stent-assisted coil embolization seems to be safe and effective in the treatment of wide-neck intracranial aneurysms. Fenestration, early bifurcation, and duplication of the PCA are rare. So-called hyperplastic anterior choroidal artery (AChA) can be regarded as a PCA variation. Methods: We reviewed intracranial MR angiographic images of 2256 patients examined using a 3 T scanner (Achieva 3T, Philips). MR angiographic images from the skull base to the intracranial region were obtained using the standard time-of-flight technique without contrast media. Excluding 51 patients whose MR angiographic image quality was insufficient or whose PCA(s) was occluded, we retrospectively evaluated the images of 2205 patients using a PACS system. Result: PCA fenestration was found in 11 (0.50%) patients. Most were found at the P1 segment, P1-P2 junction, or P2 segment, and the majority of the fenestrations were small in size. Early bifurcation at the P1-P2 junction or proximal P2 segment was detected in 8 (0.36%) patients. Complete duplication was diagnosed in one patient. Hyperplastic AChA was found in 12 (0.54%) patients. Ten of the 12 supplied the temporal branch of the PCA, and the remaining 2 supplied entire branches of the PCA. Conclusion: PCA variations were found in 32 (1.45%) patients. Because the name hyperplastic AChA seems to be inadequate, we propose calling this variation accessory PCA or replaced PCA. Keywords ARTERIAL VARIATIONS, POSTERIOR CEREBRAL ARTERY, MR ANGIOGRAPHY

S. Suh 1 1 Gangnam Severance Hospital, Yonsei University, Seoul, SOUTH KOREA Purpose: Several definitions have been proposed to distinguish from the daughter sac in treatment decision of the unruptured intracranial aneurysms. The aim of this study was to evaluate interobserver variability of aneurysm morphology, including the daughter sac, from the International Study of Unruptured Intracranial Aneurysms (ISUIA) and The Unruptured Cerebral Aneurysm Study of Japan (UCAS). Methods: After approval by the institutional review board, we analyzed 4 morphological definitions (daughter sac, lobulation and irregular margin) from the ISUIA and UCAS using angiographic images of 102 saccular aneurysms. 4 independent readers interpreted each morphological criterion with the dichotomized scales (existence or not). The kappa statistics were performed to measure interobserver agreement and kappa > 0.6 was considered substantial agreement.

Result: In discrimination of the daughter sac, interobserver agreement among 4 readers was substantial for the UCAS (kappa = 0.626 in 2D and 0.659 in 3D images) and not for the ISUIA (kappa =0.487 in 2D and 0.473 in 3D), which had a significant difference. Irrespective of the used images, pairwise pooled kappa values for the UCAS were more than 0.6 except one case (score of 0.54 between reader A and B). In proportion of positive reads, there was significant difference between reads of daughter sac by the UCAS and those by the ISUIA. Conclusion: In discrimination of the daughter sac, the UCAS definition showed a higher reliability than the ISUIA. However, a further prospective study is necessary to validate this definition as treatment standard for the unruptured intracranial aneurysm. Purpose: Endovascular embolization is a well-established treatment of ruptured and unruptured intracranial aneurysms, but concern about its long-term stability are still present. To date, few data is available about the long term anatomical results after coil embolization and there is no evidence on how long it is necessary to sustain imaging follow-up. The present study aimed to address whether it is necessary to pursue late imaging follow-up, by comparing recanalization, retreatment and newly detected aneuryms in a prospective cohort of patients harboring coiled aneurysms imaged 5 and 10 years after treatment.

Methods: This was a retrospective analysis based on a prospectively collected cohort of patients with intracranial aneurysm treated by endovascular embolization from January 2001 to December 2004. In our center, since January 2001, a systematic follow-up procedure was proposed to each patients, with clinical and imaging (angiography and MRI) assessment. Here, we included all patients who fulfilled the following inclusion criteria: 1/ ruptured or unruptured intracranial aneurysm; 2/ treated by endovascular coiling only; 3/ imaging follow-up available at 5 and 10-years after treatment; 4/ without severe artifacts. We tested whether there was a difference in clinical and imaging data at 5 and 10-years of follow-up. Result: Among the 240 aneurysms (178 ruptured, 62 unruptured) treated during the inclusion period, 120 completed the 10-years imaging followup (80,0% of the survivors). Recanalization occured more frequently before 5-years than thereafter (between 5-10 years) (21,7%vs8,3%,P<0, 0001). This result was sustained in ruptured and unruptured subgroup analysis. Retreatment was more frequent before 5-years than thereafter (16,3%vs5,8%,P=0,01), and there was one case of rebleeding. The proportion of newly detected aneurysm was small and comparable at 5 and 10-years (1,5%vs3,3%,P=0,43). We identified ruptured aneurysms (P=0, 02 ;OR not assessable due to only positive cases) and development of a neck remnant during the first 5-years (OR 6, 35[1, 1] ;P=0,01) as potential predictors of recanalization at 10-years. Conclusion: Recanalization and retreatment are more likely to occur within the first 5-years after coiling. However they are not so infrequent 10years after treatment. This was particularly true for ruptured aneurysms and those developing neck remnant within 5-years, so that delayed follow-up seems mandatory at least in these cases. Purpose: In Japan, this coil called ED coil-10 Extra soft (EDC-10 ES) is frequently used as a finishing coil for emobolization of cerebral aneurysms. Its very soft and flexible 30mm tip prevents kicking back of the micro catheter from the neck of the aneurysm. This presentation discusses some advantages of this ED coil. Methods: This ED coil is frequently used as a finishing coil for emobolization of cerebral aneurysms. The smallest 1.5mm size coil is available with 1cm, 2cm and 3cm primary coil lengths. In the final stage of cerebral aneurysm embolization, we often find that some detachable coils with a small primary diameter are not able to detach, because the coil and the microcatheter are kicked back outside of the aneurysm. However, even if such kicking back occurs once or twice, eventually it was often possible to detach the coil with EDC-10 ES. It is extremely soft, therefore I think the coil efficiently searches for open space inside the aneurysm and fills these spaces in. This contributes to achieve high VERs. I want to present a few cases of neuro endovascular treatment with ED coils, and consider the effectiveness and diversity of them. eg. SAH case due to basilar trunk perforating aneurysm, SAH case due to Right BA-SCA aneurysm Result: Finally, EDC-10 ES is also able to be used with a flow guide catheter, for example Magic catheter or Marathon catheter. Marathon was originally developed as a liquid delivery catheter with a 1.5-F smaller distal tip , which could be navigated further to the intracranial arteries.

Only EDC-10 ES is available for Marathon, since this microcatheter has only one marker, preventing its use for the delivery of detachable coils except EDC-10 ES. EDC-10 ES are rapidly detachable , with an alarm sound notification from the generator. Therefore, it is not necessary to adjust the coil to the second marker of the microcatheter. Conclusion: ED coil is extremely soft and shows good performance , therefore it will effectively provide easy to perform endovascular operations for not only beginners but also skilled operators.

Japanese made emobolic coil,ED coil-10 Extra soft,extremely soft coil Purpose: Whilst sufficient data is readily available concerning mortality and neurological morbidity; neurocognitive outcome have been reported less frequently in patients with cerebral AVM. Alteration of sexual functioning this group is almost unheard of. The aim of the study is to elucidate and establish pre existing neurocognitive deficits and sexual functioning in AVM patients and their post intervention status alterations. Methods: This is a prospective study of male patients with cerebral AVMs who underwent neuroimaging prior to treatment work up . Detailed neurocognitive assessments for both pre and 6 months post intervention were performed (surgical excision, neuroendovascular procedures) and also those who were conservatively managed. The neuropsychological performances were measured using the Screening-Neuropsychological Assessment Battery while the sexual functioning of these patients were assessed using the Nowinski and Licocopolo's Sexual History Form. Anatomic imaging details of the AVMs were documented for association study and analysis. Result: There were 11 male patients recruited (mean age : 35.5 years).Significant alteration in both neuropsychological performance and sexual functioning were seen among these patients. Patients who were surgically managed and those who underwent endovascular procedures performed poorly in most domains including attention, memory and executive function. Impaired preoperative sexual functioning status were mostly unchanged post procedures. Structural anomaly or architectural alteration to the frontal, extrastriate, posterior parietal cortexes and as well as the anterior cingulate,ventral striatum, septal nuclei and corpus callosum were noted. Conclusion: Changes in neuropsychological performance and sexual functioning among patients with cerebral AVM is more common than previously thought. Changes in sexual functioning are more common in frontal AVM than other substructures in the limbic circuitry. While some improvements were noted some functions, further deterioration of cognitive functions were also seen. Periodic pre-operative and post operative assessment may enabling better prognostication, patient management and rehabilitation. Patients' age, sex, Hunt-Hess score at presentation and vasospasm evaluated with TICI (Thrombolysis in Cerebral Ischemia: grade 0 (no flow) grade 3 (normal flow)) and regional leptomeningeal score (rLMs) were recorded and correlated using a multiple logistic regression analysis (p<0,005 

C. Pinheiro Ferreira Alves 1 , A. Carlos Maia Junior 1 , A. José da Rocha 1 1 Santa Casa de Misericórdia de São Paulo, São Paulo, BRAZIL Purpose: The aneurysmal subarachnoid hemorrhage is a common and serious condition. Vasospasm in its critical period (3-10 days after the ictus) is consider a relevant find for poor prognosis. The present study evaluated the accuracy of CT angiography for moderate / severe vasospasm detection in its critical period and the incidence of cerebral ischemia. Also evaluate possible subgroups of patients with imaging findings imposing greater risk of developing ischemic stroke after acute SAH.

Methods: The study included 36 patients with CT or laboratorial diagnosis of aneurysmal SAH<72 hours after applied exclusion criteria. Angio-CT control study performed in the critical period were subsequent correlated with digital angiography as the gold standard method.The first CT exam was evaluated by two neuroradiologists which later also evaluated the control Angio-CT and CT. The neuroradiologists were unaware about digital angiography. Comparative analysis was performed between the methods for vasospasm diagnosis and determined the incidence of delayed ischemic stroke and distribution in subgroups according Fisher graduate. Result: Were diagnosed 26 cases of moderate / severe vasospasm (72, 2%), with agreement between the methods presented 92,8 % sensibility and 90,9% specificity for CT angiography. The presence of ischemic stroke resulting from the delayed vasospasm is demonstrated in fourteen patients (53,8%). The occurrence of SAH Fisher 3 or 4 related to higher incidence of vasospasm and delayed ischemic stroke Patients with acute SAH Fisher 1 or 2 showed no moderate / severe vasospasm on Angio-TC or digital angiography. No patient in this subgroup had delay ischemic stroke. Conclusion: Our data indicate that CT angiography is highly specific for the diagnosis of moderate or severe vasospasm. As an additional finding was observed an incidence of ischemic stroke in about one-half of this cases demonstrating a relatively low correlation between moderate and severe cases of vasospasm and presence of delayed cerebral ischemia. The diagnosis of moderate / severe vasospasm (> 50 % ) with Angio-TC , regardless of the location of the aneurysm, was predictor of delay ischemic stroke.

Neuroradiology (2015) 57 (Suppl 1):S1-S169 S111 Purpose: The rupture of intracranial aneurysms is most commonly presented as subarachnoid hemorrhage (SAH). However, there are atypical clinical and radiological presentation described. The imaging findings of ruptures of intracranial aneurysms have close correlation with bleeding sites and the correct diagnosis can greatly interfere in the conduct. We have reviewed the atypical radiological presentations of bleeding related to intracranial aneurysms to facilitate the correct diagnosis of its various forms.

Methods: We reviewed the records of a series of patients that evaluated and intracranial CT angiography performed and diagnosis of intracranial hemorrhage due an aneurysmal rupture between 2011, january to 2014, december, in those patients with surgical confirmation on digital angiography. Result: The various presentations were exposed in a didactic way and our results confronted with available literature data. Conclusion: Atypical presentations of rupture of intracranial aneurysms are infrequent, despite this, the radiologist plays a crucial role in the recognition of all forms of this serious condition, whose prognosis depends directly on the early diagnosis and right conduct. Purpose: Small cerebral aneurysms are technically challenging to embolize because of difficult catheterization and high risk for intraoperative rupture. Because of the unfavorable sac/to/neck ratio, it is almost always necessary to use stent-assisted coiling. We analyzed our data for seven patients treated by stent-assisted coiling for wide-necked small intracranial aneurysms to evaluate the feasibility and efficacy of endovascular treatment for these lesions. Methods: Five patients were treated for unruptured aneurysms sized 3 -4 mm, while two cases were ruptured, blister-like aneurysms (Image 1). There were six women and one man aged from 37 to 67 years. The localization of aneurysms was supraclinoid ICA in 5 cases and posterior circulation in 2 cases (one origin of SCA and one P1 segment). We used LEO+ stent in four cases, LVIS stent in one case and Enterprise stent for 2 cases in posterior circulation.

Result: In five cases the procedure was successfully completed without complications. In one case in-stent thrombosis developed after placement, that was treated by thrombolytic intraarterially; the procedure was interrupted without coiling. On the control angiography stent was normally patent and the most part of small aneurysm spontaneously thrombosed, so we decided that no other treatment was necessary. In one case of blister-like aneurysm, after stent placement the aneurysm shrinked to size under 2 mm, so we interrupted the procedure. Conclusion: Although technically difficult, stent assisted coiling of small aneurysms may be an efficient approach for their treatment. The presence of stent may induce spontaneous thrombosis of aneurysm in some cases.

Small aneurysms,Stent-assisted coiling,Blister-like aneurysms

Methods: We prospectively retrieved records of 26 consecutive patients with ruptured radiation-induced carotid artery pseudoaneurysms that were treated endovascularly from 1999 to 2015. Clinical records and imaging findings were retrieved and analyzed after treatment.

Result: Most pseudoaneurysms were arising from petrous segment of ICA (46%), followed by cervical segment (33%) and lacerum segment (17%). Therapeutic complete occlusion of the affected artery was performed in 7 patients, and stenting was performed in 19 patients. Immediate hemostasis was achieved in all patients. 21 (81%) patients were discharged successfully from hospital, and 19 patients (73%) without any major neurological defects (mRS <2). There were total 7 complications encountered. Two patients rebleed and five patients encountered cerebral infarctions. Three (16%) complications occurred in patients with stenting performed; whereas, four (57%) cerebral infarctions occurred in parent artery occlusion. Five mortalities (19%) happened within 30 days postop, three were from parent artery occlusion technique, whereas two were treated as parent artery stenting. The result of this study showed statistical significant differences in complication rates (p<0.05) and mortality (p<0.05) between the two procedures. Conclusion: Post-radiotherapy related carotid artery pseudoaneurysms formation is a rare and life-threatening condition. Long term results from this study showed lower complication and mortality rates for endoluminal vascular stent reconstruction than parent artery occlusion in treating these pseudoaneurysms. Aneurysm, false;,endovascular therapy;,ruptured Purpose: -To present two cases of symptomatic edematous enhancing brain lesions following endovascular treatment of aneurysms and describe the MRI features -To highlight the difficulty of the diagnosis and discuss differential diagnosis -To discuss the pathophysiology of this newly-described pathology presumably due to granulomatous foreign body reaction against emboli of hydrophilic coating polymer of catheters -To discuss the treatment and the outcome of the pathology Methods: From 2013 to 2015, we retrospectively reviewed two cases of remotely-appearing brain enhancing lesions, following endovascular treatment of an aneurysm. We described the clinical, biological and imaging features as well as the materials used during the procedures. We performed a comprehensive review of the literature.

Result: Our first patient was a female patient aged 56 and our second patient a male aged 45. The enhancing brain lesions appeared respectively two months and one month following the endovascular procedures. The lesions were discovered following seizures in the first patient and phasic disorders in the second. The enhancing lesions were peripheral with a cortico-meningeal topography, within the territory where the vascular procedure was performed (respectively the right and left internal carotids), making embolic phenomenon very likely. They consisted of nodular or micronodular enhancing lesions with peripheral edema and micro-abcesses in one patient A comprehensive enquiry allowed to rule out infectious or neoplastic lesions and other granulomatous affections like sarcoidosis. Brain biopsy was performed in one patient and showed lymphocytic inflammatory infiltration with slight vascular lesions. Corticosteroid treatment allowed the regression of the lesions and the symptoms in both patients. Conclusion: Brain enhancing lesions following endovascular treatment of aneurysms are rare. However, due to the increasing number of these procedures, their incidence may increase in the years to come. Though some cases have been described to be asymptomatic, both of our patients were highly symptomatic and required a specific treatment. The imaging patterns must be known from radiologists because the diagnosis is difficult and they may be mistaken for infectious or neoplastic lesions. The purpose of the present study was to report our experience with endovascular treatment of 20 patients with ruptured intradural vertebral dissecting aneurysm. Methods: Between November 2007 and August 2014, 20 patients with ruptured intradural vertebral dissecting aneurysms were treated with endovascular modalities, which consisted of internal coil trapping, stent-assisted coil embolization and multiple stents overlapping placement. Post-procedural complications including infarction and recurrent hemorrhage were retrospectively reviewed and clinical outcomes were evaluated at discharge and follow-up clinics 6 months later using mRS. Result: Twenty patients with ruptured vertebral dissecting aneurysm were enrolled in the present study. Internal coil trapping was performed 14 patients and stent-assisted coil embolization was applied to 2 patients. Multiple stents placement was used for 4 patients. Combined surgical bypass with coil trapping was used for managing 1 patients. Two patients underwent stent-assisted coil embolization showed post-treatment infarction and hemorrhage with mRS score 6. Among 14 patients managed with internal coil trapping, 9 patients showed post-treatment infaction and post-treatment hemorrhage was occurred in 1 patient. Four patients were treated with multiple stent placement( > 3) and non of the patients experienced ischemic or hemorrhagic complications. Nine patients with infarction showed excellent or favorable clinical outcome of mRS from 0 to 3. Three patients with rebleeding and concomitant infarction were revealed poor outcomes of mRS 4 or 6. Imaging follow up was obtained in 17 survived patients, which revealed complete obliteration or stable of the dissecting aneurysm.

Conclusion: Even high-frequency of post-treatment ischemic complication, clinical outcome of deconstructive endovascular treatment for ruptured vertebral dissecting aneurysms was favorable. Poor clinical outcome was rather associated with incomplete reconstructive treatment and recurrent hemorrhage. Multiple stent placement may be an alternative to deconstructive endovascular treatment with lower morbidity and favorable treatment outcome. Purpose: The purpose is to describe the preliminary experience with the use of Pulserider in the treatment of unruptured intracranial aneurysms in 4 patients treated at our institution Methods: 4 patients (2 M, 2 F, mean age 62.4 y.o.) underwent endovascular treatment for an unruptured intracranial aneurysm (1 MCA, 2 ACoA, 1 BA) with the intention-to-treat of a PulseRider-assisted coiling. All procedures were performed under general anesthesia and full heparinizarion. All patients were premedicated with dual anti platelet therapy at least 10 before procedure (Clopidogrel 75 mg/day or Ticlopidine 500 mg/day + ASA 300 mg) and in vitro aggregation tests were performed the day before the procedure. Clinical and NeuroRadiological data were collected Result: In 3/4 cases the intention-to-treat was respected and the PulseRider-assisted coiling allowed to achieve a complete occlusion. In 1 case a perforation of the sac during the positioning of the device occurred and the procedure was rapidly converted to Remodelling Technique, obtaining a complete occlusion of the sac. All patients were discharged without neurological deficits.

No DSA follow-ups are available yet, because of the recent treatments. Conclusion: The PulseRider device allowed to achieve the occlusion in complex unruptured intracranial aneurysms located at a bifurcation. Long-term follow-up and a larger number of patients are necessary for the assessment of effectiveness, safety and stability.

Intracranial aneurysms,Unruptured,PulseRider Purpose: Intracerebral mass occasionally manifest as intracerebral hemorrhage(ICH), which must be differentiated from spontaneous intracerebral hemorrhage, caused by hypertension or vascular malformation or other non-tumorous etiology. The purpose of this exhibit is to present various brain masses, initially manifesting as acute ICH, and suggesting differential imaging clues in hemorrhagic mass, compred with pure ICH.

Methods: We retrospectively reviewed clinical findings, and CT, MR images in patients with acute ICH. Among them, we selected pathologically confirmed brain masses with initial hemorrhagic manifestation, and classified them with intra-axial, extra-axial lesions. Many lesions were included in hemorrhagic intra-axial masses, such as glioblastoma, PNET(primitive neuroectodermal tumor), pleomorphic xanthoastrocytoma(PXA), pilocytic astrocytoma, hemangioblastoma, cavernous malformation and hemorrhagic metastasis(lung cancer, melanoma, choriocarcinoma, renal cell ca). Included extra-axial hemorrhagic masses were acoustic schwannoma, hemangiopericytoma, and meningioma. We will also present the differential imaging clues between the hemorrhagic mass and pure ICH. Result: Most hemorrhagic masses usually showed localized lesion, internal septa-like structure, or layering, relatively heterogeneous attenuation or signal intensity, and showed confined outer border, compared with pure ICH. Conclusion: There are many causes in intracerebral hemorrhage, and hemorrhagic tumor must be differentiated from pure ICH for different surgical treatment. Tumor bleeding may be differentiated from pure ICH with imaging clues, which are localized form, with internal septa-like structure, or layering, relatively heterogeneous attenuation or signal intensity, and showing relatively confined outer border. Purpose: Differentiation between tumors and tumor-like lesions in the brain is essential for planning adequate treatment and for estimating outcome and future prognosis. The radiologist should be aware of all non-neoplastic pathologies and diseases that may mimic tumors. Sometimes, high-end integrating multiple modalities and clinical correlation is mandatory. A broad spectrum of non-neoplastic conditions can mimic a brain tumor, or on the contrary neoplasm can mimic a non-neoplastic lesion, both clinically and radiologically. Although tumor is often the most likely diagnostic consideration in a patient presenting with a contrast-enhancing mass lesion with surrounding edema and mass effect, that is not always the case, there can be significant overlap in the radiologic presentation between neoplastic and non-neoplastic diseases.

In this exhibit, we will present many cases of tumor-mimicking lesions, and non-tumor looking tumor lesions, and suggest differential imaging clues, with pathologic correlation.

Methods: In tumor-mimicking lesions, we included brain abscess, septic embolic infarction, enhancing subacute arterial or venous infarction, organizing chronic capsular hematoma, tumefactive multiple sclerosis or tumor-like vasculitis, neurosarcoidosis, Langerhans cell histiocytosis and inflammatory pseudotumor are included, as well as included a stroke-looking low-grade glioma, inflammatory granuloma-or vasculitis-looking brain tumors.

Result: There were included in many tumor-mimicking lesions, such as brain abscess, septic embolic infarction, enhancing subacute arterial or venous infarction, organizing chronic capsular hematoma, tumefactive multiple sclerosis or tumor-like vasculitis, neurosarcoidosis, Langerhans cell histiocytosis and inflammatory pseudotumor, and in non-tumormimicking tumor lesions, stroke-looking low-grade glioma, inflammatory granuloma-or vasculitis-looking brain tumors were also included. It is, sometimes very difficut for differential and correct diagnosis in these mimicking lesions only on imaging findings. Conclusion: How to escape from misdiagnosis in these mimicking lesions? It is very important to initially first categorize the lesion, such as tumor or nontumorous lesion. It may be as like fastening first button or tee-shot in golf. If we consider clinical information (symptom onset, progression) sufficiently, and then finding imaging clues, sometimes refering to a high-end special study information, we will escape grave misdiagnosis in a large part. Purpose: Intraventricular pilocytic astrocytomas are rare, with only a few case reports in the literature. High grade gliomas (usually glioblastomas) and highly vascularized tumors, such as hemangioblastoma, have been reported to have AV shunting and can mimic high-flow arteriovenous malformations (AVMs). Presurgical embolization of these tumors is frequently necessary to allow complete resection; however, tumors with high-flow shunts pose a therapeutic challenge and must be managed as high-flow AVMs. Methods: We present a case of an intraventricular low-grade glioma mimicking an arteriovenous malformation, and discuss angiographic findings and strategies for presurgical embolization.

Result: Here we report a case of a 22 year-old woman, who presented with severe headache and paresthesias of the right arm. Imaging revealed a heterogeneous enhancing intraventricular mass with midline shift and multiple flow voids, suggesting a highly vascularized tumor. There was no hydrocephalus. Digital subtraction angiography (DSA) showed an intratumoral high flow fistula, fed by distal branches of right anterior cerebral artery, draining to the vein of Galen and straight sinus (Fig.1 ). Endovascular embolization of two feeding pedicles of the AV fistula was performed using N-butyl cyanoacrylate. Most afferents were "en passage" feeders and, therefore, only a small component of the fistula was embolized. Polyvinil Alcohol (PVA) particles were used to embolize part of the remaining tumor blush, fed by postero-lateral choroidal arteries. A first partial resection was performed via interhemispherical approach, and pathology revealed pilocytic astrocytoma (grade I, World Health Organization (WHO)). Three weeks later, the patient was submitted to a second partial resection, via transcortical approach.

Conclusion: A review of the literature yielded 17 cases of intraventricular pilocytic astrocytoma. Only three reports described the coexistence of an AV fistula inside a pilocytic astrocytoma, similar to the findings we described. The endovascular management of these tumors with high flow AV fistulas is radically different from embolization of other tumors, such as meningiomas, usually done with PVA particles. Tumoral high flow fistulas should be managed as AVMs, with liquid agents (such as glue) and carry similar risks and technical challenges as true AVMs.

Pilocytic Astrocytoma,Arteriovenous Malformation,Intraventricular Purpose: Arterial spin-labeling (ASL) perfusion imaging has proved reliable and reproducible in the assessment of cerebral blood flow in various pathologic states, including brain tumor. The purpose of this study was to determine whether ASL can be used to detect hypervascular tumors as effectively as angiographical findings in meningiomas.

Methods: ASL study was performed at 3T-MRI in ten consecutive patients with meningioma. All patients underwent DSA before surgery. Two observers independently evaluated the overall image quality. They qualitatively graded the degree of tumor perfusion and tumor stain by using a 3-point grading system on each ASL and DSA findings.

Result: In overall quality of ASL and DSA, no images interfered with interpretation. In comparisons of the tumor blood flow identified by ASL and DSA, the grades coincided in 5 cases, and ASL grades were higher than DSA grade in 4 and lower in 1. Pearson correlation coefficient was 0.55. In this series, ASL grades tended to be higher than DSA grades, and 3 patients who exhibited DSA grade3 indicating hypervascular meningiomas were rated as ASL grade 2 or 3. Conclusion: ASL may predict angiographical findings of meningiomas and may be useful in determining the indication of preoperative embolization for hypervascular meningiomas.

arterial spin-labeling,meningioma,angiography

M. Takata 1 , T Sugino 2 , Y Arakawa 1 , T Kunieda 1 , Y Takagi 1 , S Miyamoto 1 1 Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, JAPAN, 2 Department of Neurosurgery, Sapporo Medical University, Sapporo, JAPAN Purpose: Arterial spin-labeling (ASL) perfusion imaging has proved reliable and reproducible in the assessment of cerebral blood flow in various pathologic states, including brain tumor. The purpose of this study was to determine whether ASL can be used to detect hypervascular tumors as effectively as angiographical findings in meningiomas. Methods: ASL study was performed at 3T-MRI in ten consecutive patients with meningioma. All patients underwent DSA before surgery. Two observers independently evaluated the overall image quality. They qualitatively graded the degree of tumor perfusion and tumor stain by using a 3-point grading system on each ASL and DSA findings. Result: In overall quality of ASL and DSA, no images interfered with interpretation. In comparisons of the tumor blood flow identified by ASL and DSA, the grades coincided in 5 cases, and ASL grades were higher than DSA grade in 4 and lower in 1. Pearson correlation coefficient was 0.55. In this series, ASL grades tended to be higher than DSA grades, and 3 patients who exhibited DSA grade3 indicating hypervascular meningiomas were rated as ASL grade 2 or 3. Conclusion: ASL may predict angiographical findings of meningiomas and may be useful in determining the indication of preoperative embolization for hypervascular meningiomas. Tumors were characterized as either enlarged (>10% volume increase), stable (follow-up volume ±10% of the initial volume), or decreased (<10% volume decrease). Result: Within the first month following SRS a decrease was observed in 52% of the tumors in the extent of 63% in size.

Tumor reduction varied according to histopathological subtype with 38% of non-small cell lung carcinomas, 40% of breast carcinomas, 14% renal cell carcinoma and 8% of melanomas. At 2 months 20% of the lesions had a transient tumor volume increase followed by tumor regression at 3 months.

At 12 months 37% of lesions increased in volume in the extent of 41% in size. There was a significant higher tumor reduction in those carcinoma types that are considered as radiation sensitive. The best timing for follow-up imaging is at 1, 2 and 3 months to provide clinicians useful information. Conclusion: Serial MR imaging during stereotactic radiosurgery allows demonstration of volume reduction/control in many brain metastases and it may provide clinicians useful patient information aimed to make treatment decisions.

Brain metastases,stereotactic radiosurgery,MRI Result: Pre-operative MRI evaluation of tumors indicated that micro/ macroadenomas (MM 29/75; 39%) were significantly smaller than those with cavernous sinus invasion (CS; 46/75; 61%) across all measured axes (AP p<.001; CC p<.001; ML p<.001) and overall tumor volume (p<.001). Achievement of GTR, >99.5% resection as measured by post-operative MRI, was greater for the MM cohort (p=.002). Within our cohort, 80% of those classified as MM achieved GTR, while only 39% of those classified as CS achieved GTR (p=.002). Surgical evaluation of GTR (op note) was significantly overestimated (p=.002; <54%) when compared to post-operative MRI verification. MM pre-operative classification was significantly associated with surgical morbidity such as post-operative CSF leak requiring surgical intervention (10%; p=.02). Incidence of postoperative complications including diabetes insipidus (24% MM vs 8% CS; p=.05), sinusitis (17% MM; 2% CS; p=.02) and headache (41% MM; 20% CS; p=.03) were greater in the MM group (p=.02).

Overall, the CS group had a significantly better immediate postoperative course but was associated with re-growth/recurrence (p=.002). Conclusion: Precise pre-op measurements of PA verified that MM are smaller tumors than CS along each axis and that smaller tumors achieve GTR more frequently, with its advantages and morbidity. Pre-op radiologic classification of PA significantly predicted GTR, allowing radiologists to advise surgeons on pursuing GTR, altering the goal from achievement of GTR to de-bulking, potentially sparing morbidity. Additionally, patients in which GTR is unlikely could be started on immediate post-surgical therapy to prevent tumor regrowth. Damage of the oligodendrocyts and endothelial cells by radiation leads to vasogenic edema, hypoxia, necrosis and decreasing of the cellularity, at the same time, recurrent tumor contains many neoplastic cells and has an increased cellularity. This morphological specifics can be used to discriminate TR from PRI. The aim of the study was to determine the diagnostic value of diffusion magnetic resonance imaging (DWI) in differential diagnosis TR and PRI. Methods: We retrospectively reviewed 42 patients with proven cerebral rumors after radiation therapy. Entry criteria included new or progressive MR imaging enhancing lesions after treatment of brain tumor. The total 55 enhancing lesions were analyzed. The lesions were grouped according to MR enhancement that was due either TR (n=29) or PRI (n=26). Diagnosis was proven histologically in 17 cases after biopsy or surgical resection. Other lesions were considered to be RT or PRI on the basis of MRI and PET with [11C]methionine findings during follow-up period on average 17 months. Conventional MRI (T1, T2, FLAIR, post-gadolinium T1-weighted images) and DWI were performed. The data analysis consisted of apparent diffusion coefficient (ADC) maps formation from echo-planar DW images and calculation of the mean ADC values in each enhancing lesion. Regions of interest (ROI) were set manually onto ADC maps in the area corresponding to the enhancing region on the T1-WI. Recurrence and non-recurrence groups were compared by means of Mann-Whitney U test. The level of P<0,05 was set as significant.

Result: The average value for ADC was 1438±300 in RT and 998±167 in PRI. The recurrence group showed statistically significant lower ADC values than group with PRI. Threshold value equal to 1056 provided a distinction between the RT and the PRI with 69% sensitivity and 92,3% specificity. Conclusion: Thus, DWI has low sensitivity in distinction RT from PRI and should be complemented by other MRI functional technics. Result: As previosuly reported, grade tumor cellularity inversely correlates with apparent diffusion coefficient (ADC) value. However, there is some overlap between high and low grade tumors according to their ADC values. ADC is also useful to evaluate the therapeutic response and therapy-related tumor changes. MRS results do not differ from previously reported. High Cho/ NAA and Cho/Cr ratios are usually associated with fast growth and high grade, but nevertheless there is no established cutoff because of overlapping between high and low grade tumors. The presence of lipids reflects tumor necrosis and aggressiveness, almost exclusively of High-Grade gliomas. Choline reduction has been observed after chemotherapy treatment.

All the 3 perfusion techniques are complementary. Arterial-spin labeling (ASL) is acquired before gadolinium injection, whereas dynamic-susceptibility contrast-enhanced magnetic resonance imaging (DSC) and dynamic contrast-enhanced magnetic resonance imaging (DCE) are performed after the administration of contrast media. Increased tumor vascularisation is not synonymous with malignancy. In the follow-up of these tumors, PWI helps differentiating radionecrosis from tumor recurrence. DTI, MRS and fMRI may serve as a surgical guide to biopsy. Conclusion: Integration of anatomical and advanced MRI techniques is the best approach in high grade CNS children's tumors' management and monitoring.

EPO:077 Methods: A phantom using dilutions of SMOFlipid® 20% ranging from 1-20%; and a clinical study of 18 patients with glioma (grade II n=9, Grade III n=3, Grade IV n=6) were carried out using single voxel spectroscopy (SVS) using LC model to correctly classify and quantify the different component of lipids. Chemical shift gradient echo in-and opposed-phase imaging was also performed on the phantom as well as the 18 patients in a 3 T MRI. Signal loss ratios ( SLR) were obtained from the in-oppose phase images using region of interest method.

Result: The phantom study showed strong positive linear correlation between lipid 0.9 ppm and 1.3 ppm lipid concentration with signal loss ratios (SLR) obtained from the in-oppose phase (r=0.72 to 0.96, p <.001) ( Figure 1 ) . The clinical study, using three group ROC analysis based on volume under the receiver operating characteristic surface (VUS), to evaluate the discriminative ability of the SVS and SLR in differentiating the tumour grades found that SLR at solid tumour portions was the best measure for differentiation and was more reliable than SVS (highest VUS value of 0.889, 100% correct classification probabilities of grade II and IV respectively and 67% of grade III). Purpose: To present 2 cases of meningioma associated with radiologic signs of SIH (Dural Hyperintensity on FLAIR, and small ventricles and sulci). SIH occurs after spontaneous CSF leak, usually from a dural tear in the spinal canal. Methods: Retrospective review of 2 cases. Result: One of the patients had symptoms consistent with SIH, and brain and spinal MRI were solicited. A meningioma in the posterior fosa was under medical followup. The patient had orthostatic headach. Multiple radiologic signs of SIH were present intracranially and multiple radicular cysts were detected in the cervical and dorsal spine, The patient improved with medical treatment and MRI normalized.

In the other case a presurgical 3D MRI study for meningioma revealed asymptomatic signs of SIH, and surgery was un eventful, without detection of dural abnormalities. CSF pressure was not registered but appeared normal at surgery and there were no complications. Conclusion: Meningiomas are the most frequent intracranial tumor. The association of meningioma and SIH has not been described. The relationship of a dural tumor and SIH may be coincidental, but dural pathology associated with SIH seems to be increasing as non invasive highr resolution MRI advances. Purpose: The lymphoma of the central nervous system (CNS ) may present as primary disease (PCNSL) but more often as a secondary disease. The imaging features of lymphoma have a wide spectrum and can be used to narrow the differential diagnosis, and the different finds are discussed.

Methods: We reviewed the records of a series of patients with brain MRI performed and diagnosis of CNS Lymphoma by posterior histopathological confirmation. Result: Various presentations were exposed in a didactic way and our results confronted with available literature data.

Conclusion: This review and pictorial essay demonstrated the different presentations of CNS lymphoma. The radiologist plays a crucial role in the recognition of all forms of this serious condition whose prognosis depends directly on the early diagnosis and right conduct.

Imaging features,Differential diagnosis,Lymphoma Methods: 55 year-old male patient admitted with symptoms of headache and gradually worsen visual impairment in right eye. There was no pathology in physical examination therefore intravenous (IV) contrast enhanced magnetic resonance imaging was performed (MRI).

Result: There was a lesion in right cavernous sinus with relative heterogeneous mixed intensity in T2 weighted images(WI) on MRI. There was diffuse homojen enhecament of the lesion. The lesion invaded meckel cave, enfolded carotid artery approximately 180 degrees, extended to pterygopalatine fossa along with nerve traces. Lesion also extended to infraorbital region and erased the fatty planes around lateral rectus muscle. There was proptosis in right eye secondary to intraorbital extension.Primarily malignant tumor was considered and there were no additional pathologies on low dosage abdomen and thorax computed tomography (CT) and bone scintigraphy. Patient underwent surgical operation and lesion was confirmed as LCH histopathologically. Conclusion: LCH is a clonal, pleomorphic, idiopathic neoplastic disease which causes damage on various tissues with solitary and widespread accumulation of atypical histiocytic cells. Frequent between 1-3 years. Although it can appear on all age groups, appearance above 20 years of age is rare.Solitary lesions usually appears on vertebral bodies, costal bone, calvarium and long bones like femur.Usually parietal bones and rarely temporal, mandibular and maxillary bones are affected in calvarium. Involvement of sphenoid and frontal sinus, petrous apex and mastoid process are rarely reported. Cavernous sinus involvement is extremely rare and there is only a few cases in literature. in the lesion after contrast administration (Fig). Angiographic and hystopathologic evaluations of the lesion were compatible with CH.

Conclusion: CH should be considered as a probable differential diagnosis of extraaxial space-occupying lesions throughout the cranial nerves. CHs are angiographically occult vascular malformations with an incidence of 0.3 to 0.5%. They comprise 10 to 20% of all vascular malformations. They may seem sporadically or in a familial pattern.

Most of them are located intracerebral, however they have also been reported in the peripheral nervous system. CH rarely involve the cranial nerves; space-occupying lesions along the course of the cranial nerves are generally schwannomas. The differential diagnosis can be confusing. Further investigation and longer follow-up are required to better understand the natural history of CHs involving the cranial nerves.

Third cranial nerve,Hemangioma,Magnetic Resonance Imaging Purpose: Hydatid cyst is an endemically-seen parasitic disease in various countries that is caused by the larval form of Echinococcus parasites. It is endemically seen in Middle East, Mediterranean countries, Africa, South America and Australia. The disease have a course with the liver and lung involvements. Cranial involvement is relatively rare. Cyst hydatid is generally diagnosed after the radiologic examinations. In this article, the findings of a cranial hydatid cyst initially presented with restricted diffusion that mimics acute infarction is discussed. Methods: Cranial diffusion weighted and contrast enhanced conventional cranial MRI examinations was performed. Result: A 58 year-old female patient was applied to our hospital with the complaint of seizure and weakness in the hands and arms. Diffusionweighted MRI examination was applied due to suspicion of acute infarction. A restricted diffusion was suspected in left cerebellar hemisphere, left occipital lobe and right frontal lobe on diffusion weighted examination suggestiive of acute infarction (Figure 1 a, b) . The follow-up cranial examinations revealed cystic lesions with periferal enhancement in the same areas (Figure 1c, d,e) . Thorax and abdominal computed tomography examinations were performed to rule out other organ involvement. Interatrial septal cystic lesion, renal and splenic cystic lesions were also detected. The cranial hydatid cyst diagnosis was confirmed after surgery with pathologic and serologic evaluation.

Conclusion: Hydatid cyst disease is an endemically seen and the most localization of disease is liver and lung. But it can be seen in all areas and the cranial involvement is rarely seen. Hydatid cyst should be considered in the differential diagnosis of the cystic lesions of cranium. To our knowledge, our case is the first report of the hydatid cyst disease with initially presented with restricted diffusion. Purpose: A broad spectrum of intracranial cystis lesions can be identified on imaging studies.They can be neoplastic, infectious or non-neoplastic etiology. The purpose of this presentation is to prove that CT and MR imaging are highly sensitive and complementary methods for differential diagnosis of intracranial cystic lesions. Methods: A 79-year-old women presented at emergency department with sudden onset of right side weakness and speech disorders. In past history she has high blood pressure and angina pectoris. Baseline vital signs: only hypertensia. Neurologic status: dysphasia and demaged power of right upper and lower extremities. Neuroradiological imaging included Computed Tomography (CT) examination, which has been made on GE maschine, Bright Speed type. Magnetic Resonance Imaging (MRI) was done on GE maschine, type SIGNA, 1,5T, using next sequences: T1W/SE without and postcontrast, T1W/SE with fat saturation (T1W/ SEfs), T2*GE and DWI with ADC map in axial plane, T2W/SE in axial and sagital, T2/ FLAIR in coronal and postcontrast T1W/SE in axial plane.

Result: CT examination presented acute cerebral ischemia left paraventricular and well-delineated cystic extraaxial lesion, parasellar and frontobasal on the left side, fat density with peripheral calcifications. Small lesions of fat density were in basal cisterns and supratentorial sulci, too. MR imaging confirmed acute cerebral ischemia supraventricular frontal on the left. There was well delineated extraaxial lesion frontobasal, temporobasal and parasellar left, T1/T2 inhomogeneous hyperintense, diameters 23x36x24mm (AP, LL, CC), with restriction of diffusion on DWI and peripheral calcifications on T2*GE. Also, there were fat droplets in basal cisterns and supratentorial sulci. T1W/SEfs confirmed that it was ruptured dermoid cyst. Postcontrast there was no enhancement of lesion, but pial blood vessels were prominent, probably as a part of initial chemical meningitis. Patient was forwarded to a neurosurgeon for further treatment. Conclusion: We presented the patient with neurological symptoms and CT and MRI findings of acute cerebral ischemia, but incidentally we discovered very serious pathology, such as ruptured dermoid cyst. Purpose: To assess the early response changes within tumourous tissue in patients with glioblastoma multiforme (GBM) during radiotherapy treatment by use of diffusion tensor imaging (DTI) parameters, including fractional anisotropy (FA), mean diffusibility (MD), axial diffusibility (Dax), and radial diffusibility (Drad). Methods: Eleven patients with GBM underwent the brain MRI exam on 3T MRI unit (Magnetom Trio, Siemens, Erlangen, Germany), including DTI scanning. DTI scans were acquired by use of 30 diffusion encoding directions, with 3 b values (0/1000/ 2000 s/mm2), 40 axial slices, and isotropic resolution of 3 mm. The exams were performed before the radiotherapy treatment (control point (CP) 0), after 16 fractions (delivered 28.8Gy) (CP1) and at the end of radiotherapy treatment after delivered 60Gy (CP2). ROIs for DTI measurements were placed at the same position within the solid tumourous tissue in the same patient at all CPs. Average FA, MD, Dax, and Drad values were statistically analyzed and evaluated by Student T-test and Tuckey test with Statistica software package (v.12.0), with the level of confidence determined at p<0.05. Result: Statistically significant differences were observed in FA and Drad average values obtained at CP0 and CP1, with detected decrease of FA (p=0.0294) and increase of Drad at point 1 (p=0.0307). Tuckey test for all measurement at CP0 and CP1 also revealed statistically significant difference (p=0.0296) between FA and Drad average values. Statistic significance has been found for the FA (p=0.0260) and Drad (p=0.0246) average values between CP0 and CP2 as well. Tuckey test in the time interval between CP0 and CP2 confirmed the presence of statistically significant difference in FA and Drad average values (p=0.0261). We have not noticed any significant differences between MD and Dax average values in the examined group of patients between CP0 and neither CP1, nor CP2. Conclusion: Since we found FA and Drad average values responsive to intratumorous tissue changes during the radiotherapy treatment, we are of opinion that it should be considered if and how their further use may potentially contribute to detection of early response tumourous tissue changes to the radiotherapy treatment in GBM patients at the larger group of subjects.

Glioblastoma multiforme,Diffusion tensor imaging,Radiotherapy treatment Purpose: Necrotic glioblastomas multiforme can simulate intracranial necrotic metastasis in MRI appearance. The purpose of this study was to compare findings of Susceptibility-Weighted Imaging (SWI) with those of the apparent diffusion coefficient (ADC) for this differential diagnosis. Methods: SWI was performed in 31 patients with rim-enhancing glioblastomas and 21 patients with rim-enhancing metastases at 1.5 Tesla. Two observers evaluated the degree of intralesional susceptibility signal (ILSS) seen on SWI. Chi-square test was used to assess the association between rimenhancing lesion and the degree of ILSS. Average ADC was calculated in the cystic cavity. To analyze ADC between rim-enhancing lesions, ANOVA was performed. After receiver operating characteristic (ROC) analysis, area under ROC curve (AUC) was compared between SWI and ADC.

Result: The grade of ILSSs was significantly different between rimenhancing lesions in the differentiation of glioblastoma from metastasis (P=.009). When distinguishing glioblastoma from metastasis, the percentage of ILSS grade 3 was 61.3% in glioblastoma and higher than metastasis (28.6%). There was no significant difference of the ADC value between glioblastoma and metastasis. For distinguishing glioblastoma from metastasis, AUCs of SWI and ADC were 0.73 and 0.51, respectively. SWI was significantly better than ADC (P = .039). Conclusion: ILSS was useful for differentiating between necrotic glioblastomas and necrotic metastatic brain tumors. A high-grade ILSS may help distinguish glioblastomas from solitary metastatic brain tumors. ADC was limited in differentiating between necrotic glioblastomas and necrotic metastatic brain tumors.

Tumors,Susceptibility-Weighted Imagin,Apparent Diffusion Coefficient Purpose: We report two cases of late onset glioma in the surrounding surgical margin several years after focal cortical dysplasia (FCD) surgery. A literature review was also performed. Methods: The first patient is a 36-year-old female. Her right frontal lobe FCD was resected 16 years ago and she was followed up thereafter. A high intensity area in the surrounding surgical margin on a T2 weighted image (T2WI) and a fluid-attenuated inversion recovery (FLAIR) image had gradually enlarged. The second patient is a 53-year-old male. His right parietal lobe FCD was resected 5 years ago and he was followed up thereafter. A high intensity area in the surrounding surgical margin on a T2WI and a FLAIR image had gradually enlarged. Result: In the first patient, the high intensity lesion on the T2WI and FLAIR was resected and diagnosed as oligoastrocytoma.

In the second patient, the high intensity lesion on the T2WI and FLAIR was resected and diagnosed as pilocytic astrocytoma.

Conclusion: Although it is rare, it is important to note that a glioma may occur after FCD surgery.

cortical dysplasia,glioma,MRI The University of Texas MD Anderson Cancer Center, Houston, USA Purpose: Rates of psuedoprogression (PsP) following chemoradiotherapy can be as high as 30% within the months following treatment and in larger treatment centers this population can present a significant clinical and diagnostic burden. Early differentiation between true progression (TP) and PsP often affects management decisions particularly in the era of progressive individualized glioma treatments. We sought to review the clinical performance characteristics of dynamic susceptibility contrast (DSC) and dynamic contrast enhanced (DCE) perfusion imaging in a group of high-grade glial based neoplasm presenting for differentiation of PsP from TP.

Methods: A series of clinical adult patients with high-grade glial neoplasm (GBM or AA) imaged with MRI of the brain including diagnostic quality DSC and DCE perfusion imaging were evaluated. Patients were required to have either pathology follow-up or at least six-months of clinical and imaging follow-up to assess for accuracy. Only perfusion imaging was evaluated without review of current or prior anatomic imaging. DCE metrics considered were the positive enhancement integral and degree of lesion contrast leakage. DSC metrics evaluated were the negative enhancement integral, relative cerebral blood volume and the percentage of signal recovery. Result: 38 cases were reviewed of which 17 revealed findings of PsP and 21 revealed high grade glial neoplasm. (see tables) DCE performance characteristics were: Sensitivity = 30% ; Specificity = 82.4% ; PPV = 66.7% ; NPV = 48.3%. DSC performance characteristics were Sensitivity = 42.9% ; Specificity = 94.1% ; PPV = 90% ; NPV = 57.1%. A chi-squared analysis revealed a statistically significant difference between the two tests (chisquare test = 16.1 ; p < 0.05). Conclusion: Clinical performance of DSC and DCE perfusion imaging showed robust specificity, but poor sensitivity in separating TP from PsP. The performance of DSC was superior although post-processing may not have been optimal and rigorous cutoffs were not required during case evaluation, as is more typical during clinical evaluation. This experience is not at odds with some prior reports about difficulties differentiating PsP from TP versus the higher accuracy of differentiating radiation necrosis from progression. This data will be used to drive further internal QA/QC and direct future diagnostic endeavors.

Advanced Imaging,High grade glioma,Pseudoprogression Purpose: Although MR perfusion evaluation of adult tumors is well established, in pediatric population the performance of Dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion places a series of challenges, especially to produce a very compact bolus for optimal DSC imaging, requiring patient immobility, appropriate venous accesses, high-flow contrast injection. We investigate the feasibility of DSC in pediatric brain tumor using a lower bolus injection rate (3/4 mL/s), different venous access (arm, foot, hand), with and without sedation, and a standard dose (0.1 mmol/kg) of gadolinium (gadobutrol). Methods: Prospective, multicenter study evaluated DSC imaging of 12 consecutive pediatric patients with histologically proven brain tumor, imaged with 1.5T and 3T scanner (GE-EPi sequence, TR 1000-1500ms, TE 45ms, matrix 128×128, thickness 4 mm, 60 image volumes). Patient age and weight, catheter gauge and site of placement, sedation, contrast infusion parameters were recorded. Quantitative assessment of rCBV measurements of gray and white matter was performed, and percentage of signal drop and full width half maximum (FWHM) of ROI signal time curves were quantified. Qualitative analysis rCBV maps was also assessed. Result: DSC was performed in all subjects (4M, 6F, age range 3-16 ys, weight range14-50 kg), in 8 pts with flow rate of 4 mL/s and 20-ga catheter (venous access arm, hand), in 4 pts with flow rate of 3 mL/s and 22-ga catheter (venous access arm, foot, hand). Under the age of 8ys, sedation was always performed. The flow rate of 3 mL/s displayed very similar results than 4mL/, both with respect to the quantitative evaluation parameters and in the qualitative assessment of the calculated parametric maps. 

Methods: We retrospectively identified patients between January 2011 and July 2013 that met the following criteria: age >18; glioma grade 3 or 4; treatment with radiotherapy or chemoradiotherapy; new or progressive enhancement on post treatment MRI; FDG PET within 4 weeks of MRI. Absolute and relative (to contralateral white matter) values of SUVmax and SUVpeak were determined in new enhancing lesions on MRI. The outcome of PD or TIN was determined by neurosurgical biopsy/resection, follow-up MRI, or clinical deterioration. The association between FDG PET and outcome was analyzed with univariate logistic regression and ROC analysis for: all lesions, lesions >10mm, >15mm, and >20mm. Result: We included 30 patients (5 grade 3 and 25 grade 4), with 39 enhancing lesions on MRI. Twenty-nine lesions represented PD and 10 TIN. Absolute and relative values of SUVmax and SUVpeak showed no significant differences between PD and TIN. ROC analysis showed highest AUCs for relative SUVpeak in all lesion sizes. Relative SUVpeak for lesions >20mm showed reasonable discriminative properties (AUC 0.69 (0.41-0.96)). Purpose: The hemangioblastoma is benign brain tumor, however, it frequently mimics metastatic brain tumor. Diffusion weighted image (DWI) and dynamic susceptibility contrast (DSC) perfusion weighted image (PWI) is often used to differentiate brain tumor. Recently, dynamic contrast enhanced MRI (DCE-MRI) is used to evaluate microvascular changes in tumor. The aim of this study was to differentiate hemangioblastoma from metastatic brain tumor using DCE-MRI and compare the diagnostic performance with DWI and PWI. Methods: Between May 2013 and October 2014, DCE-MRI were performed in 7 patients with hemangioblastoma. For comparison, 15 patients with metastatic adenocarcinoma with DCE-MRI was selected (total 22 patients, 11 males; ages, 24-79 years; mean, 53 years). Regions of interest (ROI) were drawn on the contrast-enhanced T1-weighted images including whole enhancing lesions on each slices. DCE-MRI parameters (Ktrans, kep, ve, and vp) were calculated with philips IntelliSpace Portal software (extended Tofts model). ADC, relative cerebral blood volume (rCBV) and DCE-MRI parameters were compared between two groups. The diagnostic performances of each parameters were evaluated with receiver operating characteristic (ROC) curve analysis. We suspected a primary CNS tumor. The patient underwent surgery and the histology was B-cells primary lymphoma. Result: One of the major issues physicians face while dealing with PCNSL, is that it is not a frequent possibility in CNS pathology. There are characteristic imaging features, which may help to raise the suspicion. PCNSL typically involves the supratentorial brain. It predilects the periventricular and superficial regions, often in contact with ventricular or meningeal surface. It can also be deeply seated in the parenchyma, (deep gray nuclei,corpus callosum). Due to its high cellularity, At MR imaging DWI is often restricted and ADC values decreased. But despite these imaging features are characteristic, none of these can unequivocally differentiate CNS lymphoma from other brain lesions. Conclusion: PCNSL is a highly malignant tumor, which requires different approach in diagnosis and management compared to other high-grade malignant brain tumors. Although PCNSL has no pathognomonic imaging features, it often has a characteristic appearance on both CT and MR imaging. New imaging techniques (MRS, PWI and DWI) play important role in the diagnosis of PCNSL and differentiating it from other primary and secondary brain tumors (high-grade gliomas and metastases). This is especially important when the characteristic imaging features on traditional imaging General Hospital, Aosta, ITALY Purpose: Intracranial dermoid cysts are uncommon lesions with characteristic imaging appearances. They arise from a developmental anomaly, in which embryonic ectoderm is trapped in the closing neural tube between the 3th-6th weeks of gestationic. Their presentation is quite variable. Occasionally they are incidental findings, discovered on brain Computed Tomography (CT) or Magnetic Resonance (MR) for otherwise unrelated clinical complaints.Often there is a long history of vague symptoms, headache being a prominent feature.They become symptomatic when they comprime adjacent structures or when they rupt. Rupture of an intracranial dermoid is a rare event with considerable associated morbidity and potential mortality. Methods: We describe the case of a 41 years-old woman, occurring at emergency for minor head trauma. She presented with headache, not responsive to therapy and vomiting. CT well defined low attenuating, extra-axial mass, extending from right parasellar region to clivus.Scattered foci of hypodensity were disseminated within the subaracnoid space. MR demonstrated T1-T2 hyperintense lesion, without Gadolinium enhancement, in the middle cranial fossa, intimately associated to the right cavernous sinus and middle cerebral artery.Hypophyseal stalk and optic chiasm were slightly compressed. Scattered foci of T1 high signal intensity, suppressed in T1 fat-sat ,were disseminated throughout the subarachnoid space. CT and MR features were characteristic of a ruptured dermoid. Result: Many intracranial dermoids are asymptomatic, incidentally found. Often there is a long history of vague symptoms, headache being a prominent feature.They may become symptomatic when they comprime adjacent structures or when they rupt: the leakage of sebum into the subarachnoid space may result in an aseptic chemical meningitis.They're often first detected on CT, low attenuation values consistent with fat being suggestive for the diagnosis. MR is the preferred diagnostic procedure, for optimal depiction of the location of the tumor and the involvement of adjacent structures. Fat droplets in the subarachnoid spaces, due to dermoid rupture, are also well detected. Conclusion: Although the imaging appearance of dermoid tumors is characteristic, several intracranial lesions must be considered in the differential diagnosis: epidermoids, teratomas, lipomas, craniopharyngiomas, and occasionally arachnoid cysts. A review of all available CT and MRI images allows the radiologist to offer an accurate preoperative diagnosis. Purpose: Restoring disrupted blood-brain barriers within a glioma due to the effects of bevacizumab (BEV) occasionally leads to false favorable responses (pseudo-response) on magnetic resonance images (MRI) with contrast medium. To clarify the frequency of the pseudoresponses on MRI at the early stage of BEV treatment for glioblastomas, we compared therapeutic responses between MRI and positron emission tomography (PET) with 11C-methionine (MET). In addition, we determined when MET-PET should be performed to predict prognosis.

Methods: MRI and MET-PET were performed before, and at 4 and 8 weeks after starting biweekly treatment with BEV plus temozolomide in 14 patients with recurrent glioblastoma. The response on MRI was identified as either complete or partial response according to the Response Assessment in Neuro-Oncology criteria. The MET-PET response was defined as the tumor-to-normal brain ratio of a standardized uptake value (SUV) of < 1.6. Therapeutic responses between MRI and MET-PET were compared at each 4 or 8 weeks. Progression-free survival (PFS) rate was then compared between patients with true-and pseudoresponses at each time point. Result: Frequencies of patients whose MRI was response but MET-PET was not response (pseudo-responders) were 28.6% at 4 weeks and 35.7% at 8 weeks, respectively. Frequencies of patients whose both MRI and MET-PET showed response (true-responders) were 42.9% at 4 weeks and 28.6% at 8 weeks, respectively. The PFS was significantly prolonged among true responders at 8 weeks, but did not significantly differ between true and pseudo-responders at 4 weeks. Conclusion: The frequency of pseudo-responses on MRI within 8 weeks after starting BEV treatment was around 30%. Prognosis can be predicted more precisely by MET-PET at eight weeks, than four weeks after starting BEV treatment. Purpose: Introduction Central nervous system (CNS) involvement in cases of bone and soft tissue sarcomas in children is considered rare. In case of quite common metastases to bones the skull/vertebral column may also be involved and secondarilyepidural space and the meninges as a result of extension from the affected bones. Primary involvement of the brain and spinal cord is much rarer. Purpose To check whether CNS involvement is as rare as descried indeed. To present various morphological forms of bone and soft tissue sarcomas' metastases to the CNS.

Methods: Brain and spinal canal magnetic resonance imaging (MRI) with use of a 1.5 T scanner or computed tomography were performed in all the cases suspicious for metastatic spread of bone and soft tissue sarcomas to CNS. Skull and vertebral column metastases were excluded from the study even if the meninges and/or the nervous tissue were secondarily affected.

Result: MRI revealed CNS metastases in 15 patients, 4 girls and 11 boys, aged 5 -25 years. The incidence of CNS metastases in our material was 3% (15/520). There were 8 cases of osteosarcoma (OS) metastases, two of Ewing's sarcoma's (ES), one of chondrosarcoma (ChS), three of rhabdomyosarcoma's (RMS) and one case of malignant mesenchymoma's (MM). There were 6 cases of a single metastasis and 7 cases of multiple ones. In 2 RMS cases we dealt only with leptomeningeal spread in the brain and in the spinal cord. Calcified metastases were found in 3 patients, hemorrhagic ones in 4. In one child with RMS there were numerous solid, cystic and hemorrhagic lesions as well as leptomeningeal spread of the disease. Conclusion: CNS metastases are a rare and late form of spread of the pediatric bone malignant neoplasms, especially OS, although in our material they were much more frequent (3%) than in other, very few reports (0,7% Pathological criteria for classification as grade II include brain invasion, specific histologic patterns, increased mitoses and the presence of some atypical features. The purpose of this communication is to study common radiological findings for atypical meningiomas in order to optimize the preoperative diagnosis to decide the optimal approach and surgical agressiveness. Methods: We have retrospectively reviewed initial and follow-up brain MRI studies of 23 patients with histological diagnostic of atypical meningioma. All MRI examination had standard sequences with and without contrast and diffusion imaging. Perfusion and spectroscopy were included on isolated cases. Radiological findings analysed on primary meningiomas and recurrences were tumour size, location, margins tumor, associated brain oedema, tumour contrast enhancement pattern, presence of intratumoral necrosis, invasion of adjacent cranial structures, number of lesions and diffusion coefficient values. Result: The mean age of patients with atypical meningiomas was 53 years (range 18-79 years), 12 males and 11 females. All of them were supratentorial, with convexity and parasagital the most common locations. Fourteen patients underwent one or multiple recurrence meningiomas, mostly in the previous surgical bed. Time to recurrence ranged from 12 to 121 months and 8 patients died in a period of five years.

Large size (56%), heterogeneity of enhancement with macroscopic necrosis (47%), multiplicity (42%) and invasion of adjacent cranial structures (42%) were the most common radiological findings for these meningiomas. Conclusion: Some radiological features on MRI are very common, but nonspecific, for atypical meningioma. Therefore, presence of these radiological markers can help to predict the diagnosis and recurrence of these tumors and may directly impact their treatment decisions, specially surgical approach. Purpose: Maximal resection and preservation of neurological function are key principles in surgery for brain tumours. Resting state (task-free) functional magnetic resonance (RS-fMRI) has provided a powerful tool for description and investigation of networks underlying neurological functions, by measuring low frequency spontaneous neural activity. The aim of the tis study was to correlate motor, language and vision RS-FMRI networks with neurological dysfunctions. Methods: 67 patients with intra-axial mass lesions were recruited. RS-fMRIs (ICA method) and clinical data in 37 patients with tumors near motor cortex, 23 with tumors near Broca's area and 7 patients with tumors in temporal-occipital region were analyzed for identification of motor, speech and visual networks respectively. Result: Regarding motor function, a strong positive correlation (r=0.65) between ipsilesional motor cortex activation and finger tapping performance was observed in non-paretic patients. Statistically significant differences in motor network activation was also found when paretic patients compared to non-paretics (p<0.01) and when ipsilesional motor network was compared to contralesional one (p<0.01). Regarding speech function, a strong positive correlation (r=0.75) between left inferior frontal gyrus activation and verbal fluency performance was observed in non-aphasic patients. Statistically significant differences in left inferior frontal gyrus activation was also found when aphasic patients were compared to nonaphasics (p<0.01). Regarding, finally, visual function, a statistically significant difference (p<0.01) was found between left and right lingual gyri activation in patients with alexia-an inability to recognize letters. Conclusion: To the best of our knowledge this is the first study to validate RS-fMRI motor, speech and visual networks in patients with brain tumors. RS-fMRI is a promising tool for identification of eloquent areas in tumor surgery. Purpose: Leigh syndrome, infantile subacute necrotizing encephalomyelopathy, is a genetically heterogeneous, progressive neurodegenerative disease with characteristic bilateral symmetric lesions in basal ganglia and subcortical brain regions. Although many patients used to die without an etiologic diagnosis, a mitochondrial energy metabolism deficiency can frequently be found. Methods: The files of the patients diagnosed with Leigh syndrome during the last 25 years in Hospital Pediátrico de Coimbra were retrospectively reviewed, with particular emphasis on the brain imaging.

Result: Sixteen patients were included (10 males; 6 females). All presented in the first 3 years of life, (median age: 16 moths), except a previously healthy boy who had a severe psychotic crisis at the age of 17 years. The most common clinical features were hypotonia, pyramidal and extrapyramidal signs, respiratory rhythm abnormalities, ophthalmoplegia and psychomotor development delay. Diagnosis of a mitochondrial disease was achieved in 12 patients. It was based on molecular findings in 4 patients, 3 with a mtDNA mutation [8993T>G (2) and 14487T>C (1)] and the fourth with a SURF1 mutation (c.868_869insT) and a deletion in heterozigosity. In the others, a severe enzymatic deficiency was found: respiratory chain complex IV (4), complexes I and IV (1) and pyruvate dehydrogenase complex (1), but the molecular studies have so far been inconclusive. Evolution was severe in most patients, with 30% of them deceased in 45 months (7-180) due to brainstem involvement. In two children, CT scan was the only brain imaging available. MRI and proton spectroscopy were performed in 14 patients. T2-weighted spin echo hyperintense lesions were found in the basal ganglia of 86% (symmetric in 60%) and in the brainstem of 64% of the cases. In 5 patients there were lesions in the white-matter, supratentorial (3) or infratentorial (2). The involvement of the subthalamic nucleus was found in the SURF1 deficient patient. Lactate peaks in the basal ganglia were found in 5 cases.

The prognosis was more severe in those patients with brainstem lesions. Conclusion: Our data contributes to the knowledge of Leigh syndrome in our population. As expected, brainstem lesions in the MRI studies correlate with a worst prognosis. Purpose: Stroke is relatively rare in the paediatric population with a spectrum of aetiologies that differs from the adult population. Therefore, there can often be delay in diagnosis, leading to poor outcomes. The aim of this presentation is to provide a comprehensive review of the imaging features of paediatric strokes of varying aetiologies.

Methods: We describe, explain and illustrate the spectrum of imaging abnormalities encountered in paediatric stroke.

Result: There is a wide range of causes of paediatric stroke and the differential of underlying pathology varies with both presentation and age. We include cases from our institution of vascular aetiologies (such as Moyamoya and arteriovenous malformations), thrombosis (both arterial and venous), trauma (including arterial dissection) and infection. We also briefly examine the importance to identify any metabolic contributions to help the clinicians reach a diagnosis. Conclusion: It is important for radiology residents to recognize stroke in the paediatric population and to be aware of the wide range of underlying causes. This exhibit provides a detailed review of the imaging features of a range of conditions leading to ischaemic and haemorrhagic stroke.

Pediatric,Stroke,Emergency In this study, we investigate regional difference of brain Aβ accumulation between in subtype of LBD and in AD. Methods: We recruited 26 normal controls (NR), 33 AD, 4 dementia with Lewy body common form (DLBc), 3 dementia with Lewy body pure form (DLBp), 5 pure autonomic failure (PAF) and 3 Parkinson's disease without dementia (PD). 11C-PiB PET images were coregistered to the 18F-FDG PET of each subject. Two PET images were corrected for partial volume effect (PVC) with MRI three-dimensional spoiled gradient-recalled echo. We also placed the VOIs in 18F-FDG PET images before PVC using Automated Anatomical Labeling (AAL), and the VOIs were also applied in 11C-PiB and 18F-FDG PET images after PVC. The value of VOIs was corrected for individual differences in uptake by proportional scaling using the cerebellar VOI value (= SUVR). Group differences in SUVR of 11C-PiB and 18F-FDG PET were examined using Kruskal-Wallis test with Steel-Dwass post hoc test (for comparisons involving 6 groups) and with Steel test (for comparisons between NR and the other groups). Figure. 11C-PiB PET before and after PVC and AAL Result: Regional 11C-PiB uptake of DLBc was similar to that of AD, and that there was no area with distinctive 11C-PiB uptake in the patients with DLBc. Conclusion: There was no area with significant Aβ accumulation in the LBD groups other than DLBc.

Lewy body disease,pure autonomic failure,PET Most kinetic studies included T2 TSE or volumetric T2 SPACE sequences in the sagittal plane in neutral position, and in flexion and extension and/or with lateral movements. Thirty-five cases from our hospital practice were selected to illustrate the clinical value of the method, and included degenerative, congenital and traumatic pathology, pre and postsurgical cases and inflammatory diseases. Result: The distribution of the patient cases was the following: os odontoideum (n=1), pseudoxanthoma elasticum (n=1), monomelic amyotrophy (n=1), post-surgery of Chiari I (n=1), post-surgery of meningioma of the cervico-occipital junction (n=1), trauma (n=3), post-arthrodesis syndromes (n=6), rheumatoid arthritis (n=4), clinically unexplained syndromes/surgery planning (n=17). Qualitatively, there was a slight loss of signal in the obtained images, but this was considered not to be relevant in the overall interpretation of the exams. DMRI added information to the static exams, unravelling movement-dependent occult disease. Conclusion: We believe the described cases are paradigmatic of the potential clinical utility of dMRI of the cervical spine and the cranio-vertebral junction, particularly in selected cases and if tailored to each patient. Methods: 40-year-old female presented with a history of chronic lumbar pain and difficulties to walk. Neurological examination revealed spastic bihemiparesis, and a LP was performed as part of the diagnostic evaluation. In the next three days patient complained of headache, nausea and she vomited several times. Superficial sensibility level was at Th 9. 3T MRI of whole spine was performed.

Result: MRI showed an epidural, large, dorsal collection from C2 to S2 level, and ventral epidural collection from C2 to C6, distal thoracic and all lumbar levels. There was a slight elevation of epidural fat in lumbar, and dural compression, mainly in thoracic region. Also, there were two disc extrusions, at the levels T6 and 7, with medullary compression. 7th day after LP epidural drainage was attempted, but no fluid content was drained. Probably the catheter was mall positioned. The patient was feeling recovered. Three days after MRI was preformed again, and reviled resorption of fluid collection.

Conclusion: LP is a common neurological diagnostic procedure with a very low risk. Complication such as epidural CSF leaking after LP is relatively common in neonates and children, but there is only few cases reported in adults. In our case epidural drainage was attempted, but without any fluid drained through epidural catheter, so spontaneous resolution of this large collection occurred. Purpose: is to prove that MR imaging is superior method for detection a pathological changes in the bone marrow, in some cases more sensitive than CT and X-ray examination.

Methods: A 75-years-old women came in our hospital for the MR imaging of the lumbal spine, because of long history of lumbal pain. Previously, she had not done any other examination. Neuroradiological imaging included: 1) X-ray examination was done on VISARIS VISION C maschine; 2 Computed Tomography (CT) examination which has been made on GE maschine, Bright Speed type; 3) Magnetic Resonance Imaging (MRI) was done on GE maschine, type SIGNA, 1,5T, using next sequences: T1W/SEfs with and without contrast in axial and sagital, T2W/FSE in axial and sagital, T2/ STIR in sagital and T2W/frFSE in coronal plane. Result: MR imaging showed that the corpus of L3 vertebra is completely changed architectonics, as well as posterior elements on the left. These structures were T1W hypointense, T2W isointense, T2/STIR highly hyperintense. There was extension of the lesion to the paravertebral soft tissue on the left and to the spinal canal, with consequent minimal compression effects to the dural sack. Also, we detected propagation to the left foramen, with mass effect on left L3 nerve root. This lesion showed intensive postcontrast enchancement, so we suspected that it was metastasis. Tomorrow we done CT and X-ray imaging, which surprised us. Corpus of L3 vertebra was completely intact! Patient was sent for further examination, biopsy proved that it is metastasis of colon cancer, so she was sent to chemotherapy. Conclusion: We presented the patiend with long history of lumbal pain.

CT and X-ray imaging were practically normal, but MR examination showed very serious pathological changes, which have been proven that it was metastasis, so patient got adequate therapy. presents an advanced MR imaging technique that may provide early microstructural changes of the spinal cord, even before these are identified on conventional MR images. In our study we present our DTI data of the spinal cord in patients with cervical spondylosis, before and after surgical decompression. Methods: A total of 25 (16 males and 9 females) patients diagnosed with CS, were included in our prospective study. Their age ranged between 56-80 years. Their preoperative radiological evaluation included MRI, with sagittal T1 and T2 weighted images as well as multi-slice spin-echo DTI, measuring qualitatively but also quantitatively the Fractional Anisotropy (FA) and mean diffusivity (MD). MRI scans were repeated at 6, 12, 24 months after surgical intervention. Moreover, Japanese Orthopedic Association (JOA) scale scores were recorded. All participants had at least 24-month follow-up.

Result: The mean pre-operative JOA score was 5.1, while the mean postoperative at 3m was 6.7, at 6m was 7.9, at 12m was 8.4, and at 24m was 8. Purpose: We propose a mTLICS score for diagnosing and grading thoracolumbar spinal trauma that is based on findings that are more objective and measurable than those used in the current TLICS system. We evaluated the performance of the mTLICS system by measuring the agreement between scores determined by radiologists using both systems and actual treatment procedure delivered. Methods: We retrospectively evaluated 134 patients with acute lumbar and thoracic spinal trauma after undergoing MRI. In mTLICS, a compression fracture with height loss less than 50% was scored as one point and more than 50% was scored as two points. A burst fracture with height loss and spinal stenosis less than 50% was two points, and all other burst fractures were assigned three points. For injuries to the posterior ligament complex, the points were subdivided into three categories: an intact PLC was 0 points and definite disruption was three points. If the PLC showed focal enhancement in the soft tissue on enhanced MRI, the injury was scored as one point. If the PLC had an enhancing lesion in the bony structures, it was scored as two points. Interobserver agreements of TLICS and mTLICS scores were analyzed using the kappa statistic. Nonparametric correlation analysis was used to determine correlation among each score and the surgical intervention. Result: The correlation coefficients for total scores based on the TLICS system were moderately correlated, while those from the mTLICS system showed slightly higher correlation. If we consider a total score of 4 to be a negative surgical indication, mTLICS showed higher sensitivities than TLICS, and if we consider a total score of 4 to be a positive surgical indication, mTLICS showed significantly higher specificities than TLICS. Conclusion: The mTLICS score corrects deficiencies in the TLICS system that lead to ambiguity in the radiological diagnostic criteria. mTLICS is a more suitable scoring system than TLICS for predicting surgical management accurately, especially for morphological injuries. Purpose: We propose a mTLICS score for diagnosing and grading thoracolumbar spinal trauma that is based on findings that are more objective and measurable than those used in the current TLICS system. We evaluated the performance of the mTLICS system by measuring the agreement between scores determined by radiologists using both systems and actual treatment procedure delivered. Methods: We retrospectively evaluated 134 patients with acute lumbar and thoracic spinal trauma after undergoing MRI. In mTLICS, a compression fracture with height loss less than 50% was scored as one point and more than 50% was scored as two points. A burst fracture with height loss and spinal stenosis less than 50% was two points, and all other burst fractures were assigned three points. For injuries to the posterior ligament complex, the points were subdivided into three categories: an intact PLC was 0 points and definite disruption was three points. If the PLC showed focal enhancement in the soft tissue on enhanced MRI, the injury was scored as one point. If the PLC had an enhancing lesion in the bony structures, it was scored as two points. Interobserver agreements of TLICS and mTLICS scores were analyzed using the kappa statistic. Nonparametric correlation analysis was used to determine correlation among each score and the surgical intervention. Result: The correlation coefficients for total scores based on the TLICS system were moderately correlated, while those from the mTLICS system showed slightly higher correlation. If we consider a total score of 4 to be a negative surgical indication, mTLICS showed higher sensitivities than TLICS, and if we consider a total score of 4 to be a positive surgical indication, mTLICS showed significantly higher specificities than TLICS. Conclusion: The mTLICS score corrects deficiencies in the TLICS system that lead to ambiguity in the radiological diagnostic criteria. mTLICS is a more suitable scoring system than TLICS for predicting surgical management accurately, especially for morphological injuries. Purpose: To assess the one-year clinical and radiographic outcomes, in terms of pain-relief, bone remodeling of the treatment of Aneurysmal bone cyst (ABC) involving the spine using a new osteoconductive cement Methods: 6 consecutive patients (4 women and 2 men, mean age 28+/-10.5) were treated with using new osteoconductive bio-active cement (Cerament) for a total of 6 vertebra. All the patients complained of a pain syndrome resistant to medical therapy and all procedures were performed under fluoroscopy control with neuroleptoanalgesia using bipedicular approach. All patients were studied by MR and MDCT and were evaluated with the visual analogue scale (VAS) and the Oswestry disability index (ODI) before treatment and at one and 12 months after the procedure. Result: A successful outcome was observed in 90% of patients, with a complete resolution of pain. Differences in pre and post treatment VAS and ODI at one-year follow-up were significant.No disk and venous leakage were observed.At 1 year follow-up in all patients a bone remodeling of the vertebra was observed. Conclusion: The using of osteoconductive bioactive cement is a good option treatment with normal bone regrowth effect in patient affected by ABC Purpose: To evaluate the faisability and accuracy of vertebral augmentation with Spine Jack system in vertebral fractures older than 1month. Methods: 19 patients with vertebral fracture with important kyphosis (11 cases) and/or intra spinal bone fragments (17 cases) were treated with spine jack expansion device between one month and one year after the fracture. The vertebral augmentation was realized under general anesthesia during a short hospitalisation of 2 days. Result: vertebral augmentation was realized in all cases with a spine Jack followed by PMMA ciment injections (6-9cc) in the vertebral body. A significant reduction of kyphosis( > or = 25%) was obtained in 9/11 patients. Satisfactory stabilization was obtained in all cases. No immediate nor delayed complication occured. All patients were discharged from the hospital the day following the procedure. All patients, except one were reviewed at one month with a very good pain relief and improvement of functional disability. Purpose: Spondylolysis and spondylolysthesis are a common cause of low back pain (LBP). Our purpose was to functionally evaluate symptomatic pediatric patients with AL-MRI. Methods: In last 19 months we studied 12 Patients aged 10-18yo. All referred LBP; 7/12 had sporadically sciatic pain in L5 territory. At plain X-ray a spondylolysis was suspected/detected and a spondylolysthesis was present in 10/12. The AL-MRI examinations consisted of basic acquisitions without load followed by the same with the use of the "Axial Loader" (at least ALSagT2 and AxialT2) after administration of 50% of body weight; a post-processing allowed cine-loop of the similar images in order to obtain "functional" Cine-AL/MRI images of the lumbar spine. Result: All Patients referred the comparison/increment of their symptoms during AL. Spondylolysis was well identified and we observed an increment of the spondylolysthesis (1 to 4 mm) in 10/12 Patients). Always we could evaluate the compression of L5 roots inside the foramina.

Conclusion: In this still limited group of Patients AL-MRI seems to be a good method for an anatomical and functional evaluation of the pediatric lumbar spine; in particular in spondylolysis and spondylolysthesis we could well study the dislocation of L5 body and directly and functionally evaluate the compression of L5 roots with cine AL-MRI. The examination is easy to perform and easily repeatable. If this data will be confirmed in more numerous series of Patients, since the absence of radiological exposition, this examination could become a reference one in the study of pediatric spondylolysis. AL-MR,Spondylolysis,Pediatric spine Conclusion: Standing cone beam CT myelography is an excellent adjunct to conventional CT myelography, and can demonstrate posturally dependent changes not seen using conventional technique. Standing myelography is inherently more physiologic than using compression devices in the recumbent position or even upright MRI which is often performed in sitting position; not standing. . They were submitted with low back pain and their MRI were read with at least a 14-day interval between assessments. Radiologists were blinded to clinical and demographic characteristics of the patients and to their colleagues' assessments. Disc degeneration (DD), disc contour abnormalities (DC) and spinal stenosis (SE) were classified following standard criteria. A semiautomatic CAD software was developed with same criteria and tested twice in the same 53 patients by an engineer unaware of previous findings. Fleiss kappa (k) statistic was used to assess intra-and interobserver agreement as well as reliability. From radiologists readings, using a latent class analysis, a final judgment was established on the existence of DD, DCA or SE (two latent classes -2LC-), at different spine level of each subject. Against this judgment the result of software was analyzed. A multiple regression model (MRM) explored how this agreement (kappa) between software-2LC varied with reading moment, location, lesion type and degree of agreement between radiologists. Reliability was defined as agreement between two results of the software test in the same patient. Result: Software reliability ranged from substantial for DD (range, according to location: 0.65-0.81) to perfect for DC and SE (range 0.84-1). The software-2LC agreement followed a pattern similar to the agreement between radiologists: tend to be slight for EE (range 0.04-0.05), between slight and fair in DD (range 0.03-0.33) and between fair and substantial in DC (range 0.11-0.72). The agreement was significantly worse for SE than DC (coefficient in MRM: -0.22), and was influenced directly by the degree of consensus of information from which the classification is constructed (coefficient rater-kappa 0.75 Clinicians were blinded to assessments made by their colleagues and to their own previous readings. No assessment criteria were established before the study. The SINS score agreement was tested by Intraclass Correlation Coefficient (ICC). Fleiss kappa statistic was used to assess intra and inter-observer agreement. Subgroup analyses were performed according to clinicians' specialty, years of experience, and type of hospital. Result: For metastases location inter-observer agreement was "almost perfect" at lumbar spine, and substantial at the other levels. Overall agreement with the tumor board classification was "substantial" (k=0.71) Inter-observer agreement was almost perfect for the Tomita score and substantial for the Bauer one. Regarding, SINS, inter-observer agreement was "moderate" (ICC=0.55). Intra-observer agreement in SINS category was "substantial" (k=0.61), while inter-observer was "moderate" (k=0.42). Concerning, ESCC inter-observer agreement was "substantial" (k=0.63). Although medical oncology scored the lowest agreement (k=0.448), no statistical differences were found with other specialties. In general, results were similar across specialties, years of experience and hospital category. Conclusion: Agreement on the assessment of SINS score is moderate. However agreement in the assessment of other metastatic spine disease scores and location is high. These scores can help improve communication among clinicians in oncology care. COI This abstract contains information from a paper accepted and two others submitted for publication, neither of them yet on paper. This study was funded by the Kovacs Foundation, a not-for-profit Spanish institution specializing in neck and back pain research, and with no links to the health industry. was performed with a dual-source scanner between two days from MRA and was used as reference standard to assess MRA's accuracy. Evaluation was performed in an off-site blinded read. The two gadolinium-based contrast agents (GBCA) were compared in terms of image quality, the degree of stenosis, plaque length and morphology. Accuracy evaluation and ROC curve analysis were performed using CTA as reference standard; Z-statistics was used to compare accuracy of the two GBCAs. SNR values were compared using the Independent-Samples T Test.

Result: Images quality was adequate to excellent for both GBCAs, according to the Mann-Whitney test there wasn't a statistically significant difference between the GBCAs (p=0.165). Gadoteridol enhanced MRA's accuracy for he degree of stenosis was 93% whilst to detect ulcerated plaques was 76%. Gadobutrol enhanced MRA showed an accuracy of 94% to determine the degree of stenosis and 94% in detection of ulcerated plaques. According to zstatistic there was not a statistically significant difference in the diagnostic performance of the GBCAs (p=0.936 Purpose: Extotoxic neurotransmitter, glutamate (Glu), is released from glutamatergic neurons into synapse, which is taken up by surrounding astrocytes through Glu transporters (GLT1 and GLAST in mouse brain). The excessive Glu results in excessive activation of NMDA receptors, triggering various processes resulting in necrotic cell death or apoptosis. The excitotoxicity of Glu has been proposed to underlie the pathogenesis of neurologic and neuropsychiatric disorders, including epilepsy, neonatal hypoxic-ischemic encephalopathy, autism spectrum disorders, and obsessive-compulsive disorder. To evaluate the neurochemical derangements resulting from synaptic Glu accumulation, we examined astrocyte-specific GLT1 inducible knockout (GLASTCreERT2/+/GLT1flox/flox, iKO) mice brain. Methods: We performed proton MR spectroscopy (1H-MRS, PRESS; TR/TE/NEX=4000/20/256) of the thalamus and cortex of GLT1 iKO mice (n=2), which exhibit excessive self-grooming (143 and 138 dur-ing10 mins), and wild-type mice (n=5, grooming 6-17 during 10 mins), with a 7.0 tesla magnet (Avance-II, Bruker Biospin). 1H-MRS was quantitatively analyzed using the water scaling method of LCModel, and the concentration is estimated abnormal when it is over or under mean±2SD of wild-type mice. LFB staining and immunohistochemical analysis with anti-GLT1, NeuN, Gfap antibodies were also performed. Result: In the thalamus and cortex of GLT1 iKO mice, 1H-MRS revealed decreased concentration of choline (Cho) , creatine (Cr), and myo-Inositol (mIns) and taurine (Tau), and increased glutamine (Gln) with normal Glu and N-acetylaspartate. GLT1 immunostaining in GLT1 iKO mice showed sparse and weak staining. LFB, GFAP, and NeuN staining showed no difference between GLT1 iKO and wild-type mice. Conclusion: Decreased GLT1 activity results in increased intrasynaptic Glu, which is taken up by astrocytes through GLAST or residual GLT1, and is amidated to a harmless compound, Gln, by Gln synthetase present only in astrocytes. Increased Gln on 1H-MRS may, therefore, result from the increase Gln concentration in astrocytes. Decreased Cho, mIns and Tau may be explained by volume-regulatory release in response to astrocyte Gln accumulation, which is also observed in patients with hepatic encephalopathy or the urea cycle disorders, both having anmonia-induced astrocyte Gln accumulation. , whose AN had been in progress for less than 6 months, drug naive and with no other psychiatric disorders were included in this study. A group of 12 right-handed, age-matched healthy female adolescents (mean age: 15,9; SD 1,8) were studied as control group. All subjects were assessed using structural clinical interviews and a battery of self report questionnaires. Functional magnetic resonance imaging scans at rest were obtained from all subjects. Functionally relevant resting state networks (RSNs) were identified using independent component analysis (ICA) and a dual regression technique was used to detect between-group differences in the detected RSNs.

Result: Significant between-group differences in the voxel-wise spatial distribution of the functional connectivity maps were found in the executive control network (ECN) (p < 0.05 corrected for FWE). Significantly decreased temporal correlation was observed in AN patients relative to healthy controls between the ECN functional connectivity map in a region of the anterior cingulate. The decreased RSFC found in this region in AN patients were negatively correlated with harm avoidance and body image scores (p < 0.05 uncorrected), and positively correlated with BMI (p < 0.05 uncorrected). Conclusion: Reduced executive function network activity in AN adolescents may be a trait-related biomarker of the disease and could explain the altered cognitive flexibility and decision making processes of these Conclusion: The present study shows a reduction in the thalamic and cerebellar FC in both groups of patients, suggestive of corticosubcortical disconnection. Moreover, the greater cerebellar disconnection in PSP patients reveals a different functional impact of tau-related degeneration in the two pathologies and suggests a possible role of FC changes as a biomarker for the differential diagnosis. We calculated contrast ratios of medial region of substantia nigra pars compacta (mSNc) and lateral region of SNc (lSNc) by region of interest (ROI) analysis on NMRI. We also measured specific binding ratio (SBR) defined as (striatum-whole brain) / whole brain on DaTSCAN by using QSPECT package.

Result: The lSNc contrast ratio of NMRI showed significant correlation with SBR on DaTSCAN, while there was no significant correlation between mSNc contrast ratio and SBR. processing pipelines leading to results with minimal user interaction. Still, the lack of agreement on an optimal processing pipeline makes comparison of results difficult. We aimed to determine the optimal processing pipeline for rs-fMRI analysis using a data driven approach.

Methods: Resting-state fMRI data were collected on a 3T Philips Achieva scanner (TR/TE: 2000/30ms , 36 slices, 3x3x4mm voxels, 260 volumes) in 32 healthy participants (age: 25.3±5.3, 20 males). Data was processed with different combinations of smoothing, band-pass filtering, motion correction, mean white matter / mean cerebrospinal fluid /global signal regression, anatomically-derived principal component regression. Data-driven comparison of the different processing pipelines was based on the maximization of derived correlation metrics within subdivisions of the default mode network and the dorsal attention system and a concurrent minimization of correlation metrics between primary motor, visual and auditory cortices. Result: We observed high, albeit non-specific correlations in our networks of interest even without preprocessing, however a proper increase of specific and decrease of non-specific correlations can only be achieved with band-pass filtering and noise-signal regression. We found a saturation of correlation specificity and a decrease in correlation sensitivity above removing >5 principal components, while robust anticorrelated networks also start to appear at the same level of filtering. Despite the tuning, motion regression cannot fully eliminate motion-derived spurious correlations. Conclusion: The optimal pipeline consists of spatial smoothing, bandpass-filtering, motion regression, and the filtering of 5-5 principal components derived from white matter and cerebrospinal fluid compartments. It is possible to tune rs-fMRI processing by concurrently maximizing correlations in connected networks and minimizing correlations between unconnected regions of interest. It is easy to generalize our method to assess other possible processing pipelines. Nevertheless, residual motion-derived signal fluctuations need further investigation. More interestingly, some have symptoms for CM even without enough tonsillar herniation. Thus, cine cerebrospinal fluid (CSF) flow study may be more robust to make a diagnosis of CM. This study, however, is usually performed additionally after obtaining routine brain imaging, and needs longer acquisition time. Three-dimensional T2 sampling perfection with application-optimized contrasts using different flip-angle evolution (3D T2 SPACE) is very sensitive to CSF bulk motion. We, therefore, hypothesized that this imaging can be used to stratify patients with CM and may find patients without tonsillar herniation but with CSF flow disturbances at the foramen magnum.

Methods: We retrospectively enrolled patients who showed CSF flow disturbances at the foramen magnum on 1-mm isovoxel sagittal 3D T2 SPACE or showed tonsillar herniation on 5-mm 2D T1-weighted sagittal imaging (T1WI). CSF flow disturbances on 3D T2 SPACE were determined when there were areas of dark signal intensity superimposed on lower cerebellum and/or cervical spinal cord (mild) or areas of dark signal intensity completely obliterating the surrounding brain structures (severe were calculated for each DCE-MRI. In addition, rotarod testing was performed before tMCAO, and on days 1-9 after tMCAO. Myeloperoxidase (MPO) immunohistochemistry was performed to identify infiltrating neutrophils associated with the inflammatory response in the rat brain.

Result: There was a statistically significant decrease in Ktrans and Kep at the infarction site in the cold-saline group compared with the control group (P < 0.05) and a decrease in Kep that approached significance in the cold-saline group compared with the warm-saline group (Kep: cortex, P = 0.0892 basal ganglia, P = 0.0925). The percentage of MPO-positive cells in the cold-saline group was significantly lower than those in the control and warm-saline groups (P < 0.05). However, behavioral testing did not reveal a statistically significant difference among the three groups. Conclusion: Localized brain cooling can inhibit the increase in BBB permeability that follows transient cerebral ischemia and reperfusion in an animal model. had the shortest ATT. Conversely, ABZ and PBZ showed the lowest CBF and the longest ATT. In MCA territory, absolute CBF values were not correlated with CAS severity. However, the ATT in the MCA territory ipsilateral to CAS was longer than in the contralateral side, and the ATT ratio ( ipsi-/contralateral) was significantly higher in patients with >90% stenosis compared to those with a <70% CAS. ABZ and PBZ angles in the hemisphere ipsilateral to CAS were larger than in the contralateral hemisphere, and significantly correlated with the stenosis degree. Conclusion: Downstream territories in CAS show longer ATT and larger borderzone angles, increasing with the stenosis severity. This suggests an increased territory at risk of heamodynamic stroke in patients with CAS, despite preserved CBF possibly through autoregulation and collateralisation. Purpose: Brain temperatures (BT), which mainly depends on the imbalance obeying the heat removal theory, can change abnormally in hemodynamic impairment diseases such as Moyamoya disease and stroke patients. Carbon monoxide (CO) poisoned patients can also show the imbalance between cerebral perfusion and metabolism in the early phase after CO exposure. Cerebral white matter (CWM) damage, which reduces the brain metabolism, was observed in CO-poisoned patients, BT may thus depend on the extent of damage. Mean diffusivity (MD) and fractional anisotropy (FA), which are quantitative parameters calculated from diffusion tensor imaging (DTI) dataset, are used for assessing BT and the extent of CWM damage, respectively. Here, we investigated whether relationship BT and CWM damage in the subacute CO-poisoned patients can be assessed using only DTI. Purpose: There are increasing reports of cognitive and psychological declines related to occupational stress in subjects without psychiatric premorbidity or major life trauma.The underlying neurobiology is unknown.The aim of our study is the evaluation of cerebral volumetric and cognitive function abnormalities in patients with chronic occupational work related stress to identify a pattern of volumetric and psychological alterations which could characterize this disorder. Methods: We have submitted to our study 20 patients who have accessed to the center of Work Related Psychopathology. An assessment protocol lasting at least six months was administered to the patients in which clinical, psychopathological and working dimensions were examined.The psychopathological dimensions were measured through the use of the Hamilton Anxiety Scale (HAM-A), the Hamilton Scale for Depression (HAM-D) and the Snaith-Hamilton Pleasure Scale (SHAPS). The perception of the occupational stress was assessed by administering the Work Distress (nQ-WD).The patients were divided through these criteria into two groups: with an high pathogenesis working (group A) and with a moderate or poor working pathogenesis (group B). We have included a group of 15 subjects adjusted for sex, age and schooling as a control sample (6 F, 9 M) without any history of psychological and / or significant mental disorders.We administered the same neuropsychological tests to al subjects , represented by MMSE, FAB, BICAMS battery in order to assess their cognitive function especially in the memory domain. We investigated the volumetry in stressed subjects and unstressed controls using the international harmonized protocol developed for the manual segmentation of the hippocampus on MR images,SIEANAX and VBM analyses. Result: The stressed subjects showed a bilateral reduction in the hippocampal volume, especially in the left hippocampus(p<0.05). No significant correlations was found with the neuropsychological data Conclusion: The present study expands upon the data from animal experiments and reports from PTSD patients, and focuses on the involvement of the hippocampus in chronic stress. The finding of atrophy in regions known to be associated with chronic psychosocial stress confirms our previous conclusion that subjects reporting stereotyped symptoms from occupational stress have a medical condition requiring careful investigations and a targeted treatment. Methods: Sixty-three RRMS were enrolled in the study and classified as fatigued (F-RRMS; FSS score > 45; N=33) and non-fatigued (NF-RRMS; FSS score < 36; N=30). Thirty-one age-and sex-matched healthy controls (HC) were used as control group. All subjects underwent a 3T MRI including conventional and DTI sequences. Gray (GM) and white matter (WM) volumes were estimated using SIENAX software. WM focal lesions were identified and lesion volume (LV) and Lesion Probability Maps (LPM) were computed. The microscopic NAWM damage was explored by Tract Based Spatial Statistic (TBSS) analysis, using LPM to exclude voxels were WM lesion frequency was higher than 5%. Result: F-RRMS and NF-RRMS showed no significant differences in age, gender, disease duration, disability, LV and normalized GM/WM volumes.DTI-derived metrics of the NAWM skeleton were significantly and diffusely altered when comparing RRMS with HC. A widespread FA reduction and MD increase was found in the NAWM of F-RRMS when compared to NF-RRMS. These findings mostly located at the level of thalamus and WM tracts connected to motor/pre-motor cortices, predominantly in the right hemisphere. In the correlation analysis a significant relationship was found between DTI-derived measures of the NAWM skeleton, particularly in fronto-parieto-insular regions, and FSS scores. Conclusion: A widespread microstructural NAWM damage, especially located in the right WM tracts connected to motor/pre-motor cortex and thalamus, might be a critical factor in determining fatigue in RRMS patients. The relevance of such finding is further emphasized by the lack of significant differences in GM/WM atrophy and LV between F-RRMS and NF-RRMS. Recently emphasis has been placed on the use of analysis of eigenvalues (λ1, λ2, λ3) that are elements of the DTI to access brain development. In particular, the concept of RD has gained importance, that is as a measure of microscopic water motion perpendicular to the direction of axons. components correspond to areas of increase in isotropic (blue) and extraneurite (red) diffusion components, respectively. The information added might be helpful to guide biopsy sampling and treatment planning. Moreover, NODDI color map seems to distinguish specific patterns of diffusion compartment redistribution in case of acute ischemic stroke or hyperosmolarity injury, both characterized by restricted diffusivity on conventional diffusion weighted imaging. Conclusion: NODDI color maps represent a feasible and useful way to visualize the information provided by NODDI analysis in a practical single image summarizing brain microstructural complexity in normal appearing white matter as well as in brain pathology. Purpose: The purpose of this study is to present a protocol developed for the surgical management of lesions located in left premotor region, where fMRI and tractography-integrated navigation are used in conjunction with direct electrical stimulations (DES). Methods: A multidisciplinary team composed of neuropsychologists, neurosurgeons and neuroradiologists agreed a protocol for easy preoperative handling of patients with lesions in left prefrontal region. All imaging is performed by using a 1.5-T (Philip, Intera). We studied 18 patients: 10 high-grade glioma, 5 low-grade glioma and 3 arteriovenous malformations. The protocol consists of three paradigms' blocks (2 motor and 1 linguistic), 3D image anatomic T2 or T1 depending on the type of lesion and DTI (16 diffusion gradient directions.) DTI and fMRI data are used in joint analysis, the results of analyzing different modalities are derived separately and then are combined together to perform statistical analysis with de Philips's workstation. The results are validated with intraoperative procedures. Result: In an attempt to develop an optimized and standardized protocol, fMRI examinations have been integrated into routine presurgical planning in our hospital. Complex finger opposition of the right hand alternating with rest paradigm generates a strong activation of cortical motor network in both hemispheres (primary sensorimotor cortex, premotor cortex and proper supplementary motor area). Complex finger opposition of the right hand vs left hand identifies primary motor cortex. The verbal fluency-verb generation paradigm that is complementary to the former one, allow us to identify presupplementary motor area, generally involved in linguistic planning, in addition to classic Broca and Wernicke area and cortex premotor. To be able to compare the sequences with standard protocol sequences the contrastenhanced GRASP sequence was additionally acquired in patients with suspicion of tumors and vascular pathologies. Two neuroradiologists analysed the GRASP images and compared them to sequences used in the standard protocols (T1w post contrast, 4D MRA) with respect to delineation of pathologies and artifacts. Result: 25 patients were examined with the GRASP sequence. No pathology was observed in 8 patients. The other 17 patients had the following reports: glioblastoma (1x), meningeoma (4x; Fig. 1 ), arteriovenous malformation (1x), aneurysm (1x), pituitary adenoma (2x); pleomorphic adenoma (3x), glomus jugulare paraganglioma (2x), cavernous hemangioma (2x), squamous cell carcinoma (1x). In the contrastenhanced GRASP sequence arrival of contrast media and distribution over time was well visible in all patients with additional high regional resolution. All pathologies could be evaluated in detail. Pulsation artefacts were not observed. The image quality was still quite good when the patient moved during acquisition. Furthermore having variable temporal sampling during retrospective reconstruction was a benefit. The arterial phase was not missed because it could be reconstructed by choosing a different reconstruction pattern from the continuously acquired data.

Conclusion: The GRASP sequence provided not only high temporal but also high spatial resolution showing all pathologies in detail. Even when motion artifacts appeared diagnostic images could be acquired with the GRASP technique.

golden-angle radial sampling,neurooncology,vascular malformations To show examples of how arterial spin labeling (ASL) perfusion imaging may improve the diagnostic capability in the daily practice, as it doesn't need the strict contrast media injection protocol, can be easily implemented in the magnetic resonance imaging (MRI) examination routine. Methods: We present cases from our archives of both tumoral and non tumoral conditions in which ASL provided important information for the correct diagnosis. Result: ASL can be used for provide useful information in tumoral conditions.

We show cases of correct grading of central nerve system (CNS) gliomas with this technic, and also cases of other tumoral conditions like meningiomas, oligodendrogliomas, neuroglial tumors and metastasis. Cerebral blood flow (CBF) maps provided by ASL can also be helpful in the post-treatment evaluation. Besides neoplastic lesions, the functional information from ASL may aid in the diagnosis of other conditions like stroke, brain atrophy and microangiopathic brain lesions. Epliptic patients may show both hyperperfusion patterns during crises and in the postictal state and hipoperfusion pattern in the interictal phase. Vascular malformations like brain AVMs and proliferative angiopathy may also be evaluated by this technic. Congenital diseases like Dyke-Davidoff-Mason show an diffusely hipoperfunded brain hemisphere. ASL information can also aid in pseudotumoral demyelinizating lesion, by showing an hypoperfusion pattern. Metabolic conditions like adrenoleucodistrophy can also be evaluated with CBF information provided by ASL. Conclusion: ASL is a technic that provide functional information about the cerebral perfusion without the need for contrast media injection. It can be easily applied to an MRI examination, and can help the radiologist in many situations, from tumoral conditions to stroke and epilepsy. Hence, its important for all radiologist be familiar with this technic and its capabilities. Methods: For each voxel (V) in the cortex, extracted from automatically segmented T1-weighted images (voxel size = 1 mm3), we computed two fractal geometry related properties by counting the number of boxes needed to cover a growing neighborhood of V up to a size r-max (parameter of the algorithm). With a linear regression we derived FD (slope) and Q (intercept). We tested our method on 19 healthy controls (12 males, mean age 9.65)(HC) and 9 patients affected by various MCDs (3 males, mean age 7.82). FD and Q maps were moved to a study-specific template built from the normal gray matter (GM). We computed the global norm one distance of the normalized histogram of each subject from the reference histogram built from HC. FD around V was modeled as normally distributed, then the local distance was computed as the norm one between the probability distribution functions of S and that of HC. Voxel V was finally classified as healthy or abnormal when one of the two distances exceeded the thresholds χl, and χh, tunable parameters of the algorithm. Result: HCs and patients showed a significant difference of FD (2.416 ±0.007 for the HCs, 2.386 ± 0.019 for PATs, p=1.44E-5) and Q (2.386 ±0.019 for the HCs, 2.827±0.059 for patients, p=9.21E-5) values and of shape distribution between normal and malformed areas (Fig.1) . With a leave-one-out approach, we tuned the parameters χl and χh on the HC to maximize the accuracy of lesions' detection and to minimize the false positive rate. The best set of parameters reached an accuracy, specificity and sensitivity of 83%, 85% and 80% respectively. The area under the curve was 0.88. Conclusion: The proposed method was able to discriminate between normal cortex and malformed areas in a wide spectrum of MCDs, ranging from polymicrogyria to pachygyria. The method, appropriately tuned on a single-subject level, could help neuroradiologists in the detection of small MCD, improving the diagnostic accuracy of MRI. Purpose: The aim of this study is to assess the ability of diffusion kurtosis imaging (DKI) in the characterization of microstructure of different brain regions in patients with multiple sclerosis (MS) and in healthy volunteers without any neurological pathology. Methods: 20 patients with MS and 5 healthy volunteers (mean age 35±9 and 32 years old respectively) underwent DKI measurements with a 3T MR-scanner, using b-values equal 0, 1000 and 2500 s/mm² and 60 gradient directions. The following diffusion tensor and diffusion kurtosis scalar parameters were evaluated: mean kurtosis (MK), axial kurtosis (AK), radial kurtosis (RK), kurtosis anisotropy (KA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), fractional anisotropy (FA), relative anisotropy (RA), axonal (intracellular) water fraction (AWF), axial extraaxonal diffusivity (AEAD), radial extraaxonal diffusivity (READ), tortiosity (TORT). Afterwards, these parameters were compared between patients with MS and healthy volunteers in frontal white matter, genu and splenium of corpus callosum, posterior limb of internal capsule, thalamus, parietal white matter, putamen and globus pallidus, centrum semiovale, head of the caudate nucleus (p<0.05).

Result: Different diffusion parameters significantly differed in all brain regions, except for thalamus and posterior limb of internal capsule between patients with MS and healthy volunteers. Purpose: MPS IVa is a lysosomal storage disorder caused by a deficiency of N-acetylgalactosamine-sulfatase. Main symptom is systemic skeletal dysplasia. Affection of the vascular system has not been described yet. Goal of this study is the analysis of the vascular system in patients with MPS IVa, based on the example of the aorta. Methods: In a retrospective study, 32 patients with MPS IVa aged 10-49 years (μ 22, 5; m 21) were included. All patients were of small stature (length 106 ±19 cm).The aorta in its course from 4th thoracic vertebrae to 10th was analyzed on the basis of 49 craniospinal axial plane MR and 4 axial plane CT examinations. To describe the course of the aorta, we divided the area around the vertebral body into 5 equal parts, each at an angle of 36°. Therefore, we connected the processi transversi with a straight line and numbered the segments from right (segment 1) to left (segment 5). High buckled arteries in relation to the length of the affected aortal part were indicated as aortal kinking, and a moderate twist in relation to the length of the affected aortal part as aortal coiling. Result: 12 of 32 patients had an aortal kinking, 10 of 32 patients an aortal coiling, 4 of these had moderate and 3 strongly coiled aortae. 7 patients had a normal aortal course, 4 couldn't be analyzed. One patient revealed both, aortal kinking and coiling. Conclusion: This study reveals for the first time the occurrence of aortic tortuosity in patients with MPS IVa. Although the etiology is still unknown, we suggest, that this complication could be due to glycosaminoglycane deposition in the aortic intima respectively media, which may be associated with an increased vulnerability of the vascular wall and a rupture of the elastic fibers. Therefore, we conclude that the examination of the vascular system should be included in regular followup protocols of MPS IVa patients. Purpose: To asses global brain volume changes during natalizumab therapy in patients affected by multiple sclerosis (MS). Methods: Magnetic Resonance Imaging (MRI) scans of 20 MS patients on natalizumab therapy were retrospectively estimated to assess the percentage of brain volume change (PBVC) at baseline, 6 and 12 months by using a SPM-SIENA software.

Result: There was a significant (p < 0.5) PBVC decrease during the first year. Differences were more marked in patients with gadolinium-enhancing MS lesions (p = 0.05). Mean GMF and WMF changes during the first year of treatment were significant (p < 0.5). There were a significant (p < 0.5) correlation between the presence of active lesions and PBVC changes with a more significant (p <0.1) correlation with WMF change during the first year of treatment. No predictors were found for GMF volume changes. Conclusion: Global brain volume loss during natalizumab therapy is mainly due to WMF volume loss and it is related to the inflammatory activity present at the onset of therapy.

Multiple sclerosis,brain atrophy,natalizumab Purpose: To assess the severity of white matter lesions, WML (as determined by conventional MRI parameters i.e. WML grades and volume) and microstructural integrity of specific white matter tracts (as determined by diffusion tensor imaging, DTI i.e. fractional anisotropy, FA axial diffusivity, AD and radial diffusivity, RD values) among older individuals with a history of falls compared to non-faller controls. Methods: 88 participants, aged 64-87 years, (46 fallers and 42 non-fallers) were recruited from the Malaysian Falls Assessment and Intervention Trial (MyFAIT) cohort. T1-weighted FSPGR, T2weighted, FLAIR and DTI sequences of the brain were obtained using a 3-Tesla MRI. Severity of WML was graded from 0 to 3 using the modified Fazekas scale. WML volume was calculated using Lesion Segmentation Tool in SPM8. FA, AD and RD values were obtained from selected WM tracts using combined tract-based spatial statistics (TBSS) and region-of-interest (ROI) methods. The threshold for significant clusters in TBSS was adopted as 0.05 and for significant fraction of voxels of TBSS in each ROI as 30%.

Result: The percentage of fallers compared to non-fallers was significantly higher in the group of high WML grades i.e. Fazekas Scale of 2-3, than in the group of low WML grades i.e. Fazekas Scale of 0-1 (85.2% vs. 37.7%, OR = 9.5, 95% CI 2.92-30.96, p<0.001). The WML volume of the fallers group (median = 18.41 cm3) was also significantly higher than the non-fallers group (median = 2.87 cm3) (p < 0.001). AD was identified as the most affected marker of microstructural integrity for specific WM tracts in the fallers. The AD values of middle cerebellar peduncle, genu of corpus callosum, (both) anterior limb, (right) posterior limb and (left) retrolenticular part of the internal capsules, posterior left corona radiata, both external capsules and right tapetum were significantly higher among fallers compared to non-fallers (p < 0.05). Both FA and RD values of these tracts were not significant. Conclusion: Our data suggests fallers have significantly higher WML burden than non-fallers in the older population. DTI data suggests loss of integrity of various WM tracts in the older population with falls with AD as the most sensitive marker.

Geriatric,Fazekas,tractography Purpose: To document the longitudinal changes in the microstructural integrity of white matter (WM) tracts in the mild-complicated traumatic brain injury and mild-uncomplicated traumatic brain injury patients using diffusion tensor imaging (DTI), Methods: We performed 3T MRI and DTI scans of the brain on 39 subjects [20 mTBI with 15 complicated and 5 uncomplicated) and 19 age matched healthy controls] at 72 hours post injury (acute) . Repeated scans at 6 months post injury (chronic) were performed for all subjects. The DTI dataset was post-processed by MRIConvert, FSL and AFNI. Median fractional anisotropy (FA) and mean diffusivity (MD) were measured in middle cerebellar peduncles, corona radiata, anterior and posterior limbs of internal capsule, cingulum, superior longitudinal fasciculus, posterior thalamic radiation, genu and splenium of the corpus callosum using ICBM DTI-81 atlas as a template. Result: At acute stage significantly higher MD involving corona radiata, anterior limb of internal capsule, cingulum and posterior thalamic radiation tracts with no significant FA changes in both mild-uncomplicated and mild-complicated TBI patients compared to healthy control . At 6 months, FA of mild-complicated TBI patients was significantly reduced in the corona radiata, anterior limb of internal capsule and splenium of corpus callosum; with increased MD of corona radiata, cingulum of the corono radiata and posterior thalamic radiation compared to healthy control. Longitudinal changes of lower FA were seen in within both complicated and uncomplicated mTBI WM tracts while longitudinal changes in MD were not signficant ( Purpose: To assess the prevalence of white matter injury and intraventricular/germinal matrix hemorrhage in very preterm (VPT) born neonates (<32/40 weeks gestation) and its impact on visual-motor outcomes. Methods: Eighty-six VPT neonates (46 males; mean age at birth: 28.9 weeks; range 24.7-32.9) underwent MRI scanning within 2 weeks of birth and were assessed for the presence and grade of germinal matrix/ intraventricular hemorrhage and white matter lesions to comprise three groups: no injury (morphologically normal MRI), mild/moderate injury (isolated, linearly punctate white matter lesions with or without IVH/ GMH grades 1 to 3), and severe injury (confluent punctate white matter lesions and/or PVHI/GMH grade 4). At 2 and 4 years of age, a subset of children underwent neuropsychological assessments to evaluate motor and visual-motor abilities. At 2 years, the Bayley Scales of Infant Development 3rd edition was performed to yield a standard score of motor ability. At 4 years, the Beery-Buktenica Visual-Motor Integration 6th edition was performed to yield standard scores of visual-motor integration, motor coordination and visual perception skills. The impact of each brain injury group on visual-motor outcome measures was determined by performing analyses of covariance, adjusting for sex and gestational age.

Result: Forty-one very preterm neonates exhibited no brain injury, 34 had mild/moderate brain injury, and 11 had severe brain injury shortly following birth. At 2 and 4 years of age, 41 and 44 children returned for neuropsychological assessments. At 2 years, no group differences were found between Bayley motor scores and the three injury groups (p > 0.05) although 10 children scored below average. At 4 years, again no group differences were found between visual motor integration, visual perception and motor coordination scores (p > 0.05) although 15 and 26 children experienced below average visual perception and motor coordination scores, respectively. Conclusion: In our longitudinal cohort of VPT children, no differences were found between brain injury groups and visual-motor outcome measures at 2 and 4 years of age. As functional impairments have been shown to arise from early brain injury, this finding indicates a mechanism for compensatory neuroplasticity in our population.

white matter injury,very preterm neonates,visual-motor outcomes Methods: 70 year-old male patient diagnosed with Philadelphiapositive CML 2 years ago. After diagnosis, complete remission was achieved with 4 months of 400 mg Imatinib treatment. Patient, who was receiving maintenance therapy for 1.5 years, admitted to hospital with symptoms like difficulty in walking, balance disorder, increased movement of his limbs in sleep, sleep talking, blurred vision continuing for 15 days. Cranial magnetic resonance imaging (MRI) was performed.

Result: There are increased signals in cortical grey matter, subcortical white matter, bilateral cerebellar peduncles, periaqueductal area, brainstem and around 4th ventricle on T2 weighted images and FLAIR sequences. Diffusion weighted images showed mild increase in intensity of these areas but there were no diffusion restriction. There were increased T2 signals expanding the dural sheath of the bilateral optic nerve and bilateral papillae protrude into the vitreous space of the globe because of increased intracranial pressure. After administering intravenous (IV) contrast, thickening and enhancement was seen in bilateral optic nerves, optic tractus, bilateral 3rd and 5th cranial nerves, 7th and 8th cranial nerves. In thoracal and lomber MRI, there were increased T2 signals and enhancement in spinal cord. Enhancement was seen in all nerve roots in neural foramina and around nerve roots. Also thickening and enhancement of cauda equina fibers was present. There were soft tissue thickening in paravertebral spaces. Cerebrospinal fluid (CSF) cytology was consistent with CSF involvement of CML. Patient was diagnosed with isolated central nervous system blast crisis and treated with IV pulse steroid and intrathecal methotrexat, cytarabine and dexamethasone. Control MRI showed that earlier findings were disappeared and there were no pathological findings. Conclusion: There are cases of isolated optic nevre infiltration which caused vision loss but a case like ours, involvement of all cranial nerves and spinal nevre roots is defined for the first time in literature. Purpose: Giant axonal neuropathy (GAN) is a rare genetic disease of childhood that affects both the peripheral and central nervous system (CNS) with clinical and genetic heterogeneity. Axonal loss with several giant axons filled with neurofilaments is the main histopathological feature of peripheral nerve biopsies in this disease. Methods: Cranial magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) was performed with 1.5T MR system (Siemens Magnetom Avanto, Erlangen, Germany). We present MRI and MRS findings of the patient. Result: A 10-year-old boy had delayed motor and mental milestones, weakness and wasting of distal muscles of upper and lower limbs, progressive clumsiness of gait and progressive decline in cognitive functions with dullness. He also presented with progressive walking difficulty and recurrent falls. Evaluation showed frizzy hair, dry skin, characteristic facies, sensory motor neuropathy, and ataxia. Performed MRI showed bilateral symmetric white matter signal changes in the dentat nucleus of cerebellum. On proton MRS, an increase in choline(Cho) /creatine(Cr) ratios, a reduction in the N-acetyl aspartate(NAA)/Cr ratio, and the presence of lactate and myo-inositol peak were observed (Figure 1 ). Figure. In MRI, axial T1-weighted (a), axial T2-weighted (b), coronal FLAIR (c) images showed bilateral symmetric white matter signal changes in the dentat nucleus of cerebellum (arrows). On proton MRS (d), an increase in Cho/Cr ratios, a reduction in the NAA/Cr ratio, and the presence of lactate and myo-inositol peak are observed. Conclusion: GAN is a rare, genetic, progressively fatal neurodegenerative disease characterized by mental retardation, progressive sensory motor neuropathy and CNS involvement. Histopathologically, enlarged axons with accumulation of neurofilaments, astrocytic degeneration, demyelination and the presence of Rosenthal fibers are characteristic features of this disease. The reported imaging findings on MRI include involvement of cerebellar and cerebral white matter with sparing of the subcortical U-fibers, a variable degree of cerebral atrophy, and thinning of the corpus callosum. In MRS, mostly expected findings are decreased NAA, increased Cho/Cr and increased lactate and myoinositol in white matter. In conclusion, GAN is a chronic disease with clinical and genetic heterogeneity. Although it is a well-known disease among adults, it is our aim to report our experience in pediatric patients and to highlight the value of MRI findings in the diagnosis and prognosis of this disease. Methods: From january 2010 until december 2014, 8 patients (5 girls and 3 boys) aged from 1 to 9 years old had a diagnosis of PRES based on clinical and MRI findings. All of them had underlying diseases for which they were receiving drug treatments. 4 patients were under inmunosupressive drugs after hepatic translplant, 2 were receiving treatment for Acute Linphatic Leukemia, one patient had a neuroblastoma and another one had hemodynamic compromise after a systemic infection. Result: All patients showed the characteristic hyperintense T2 and FLAIR lesions in subcortical white matter depicting vasogenic edema.

Most of them did not show restriction in Diffusion Weighted Images (80%). 20 % did show restriction in DWI caused by citotoxic edema and lesions were therefore not reversible. Both posterior and anterior circulation territories were involved in 80 % of patients with predilection for posterior areas whereas 20 % showed only posterior compromise._ Conclusion: PRES is an increasingly recognized clinicoradiological syndrome among pediatric patients and it is frequently associated with multiple clinical and toxic disorders. As neuroradiological findings are often characteristic, MRI has become an important clue in the diagnosis. MRI diffusion weighted sequences are useful in the diagnosis as well as in giving prognostic information concerning the outcome in each patient._ The prompt recognition of MRI findings has important prognostic implications because the reversibility of the lesions is contingent on early treatment. Parkinson's disease produces neuronal loss in the substantia nigra (SN) , basal ganglia(BSG) and subcortical gray in the human forebrain.Proton magnetic resonance spectroscopy (1H-MRS) has been previously performed in Parkinson's disease(PD) to evaluate in vivo concentrations of basal ganglia (BSG)and cerebral cortex metabolites.However, this technique has never been used to evaluate the substantia nigra (SN)in PD patients. In this study ,single voxel MRS of BSG and SN was performed in PD and normal control (non PD) to evaluate the usage of MRS in PD patients Methods: Material and method: 17 PD patients (12 men,5 women, mean age 60.5(SD9.4),mean duration of the disease 5.9 yrs(SD4.2 ) ,Hoehn&Yahr stage I-III An additional 14 healthy age-matched controls, including 8 men and 6 women of mean age 55.5 yrs(SD5.8)were enrolled . Patients with evidence of brain atrophy and cognitive impairment were excluded. Result: Results: A significant reduction in the NAA/Cr ratio was observed in the SN of PD compared with controls(P<0.05).BSG spectra did not allow any evaluation due to the presence of artifacts related to inorganic paramagnetic substances. Purpose: The aim of the exhibition is to review the currently used and widely accepted visual grading and scoring systems for magnetic resonance (MR) image of the brain in dementia work-up. In addition, we present the visual atlas of structural changes of brain in variable cause of dementia. Methods: We investigated various visual scores and scales for MR imaging of brain as a part of evaluation of dementia. Among them we compiled a list of currently used and generally accepted scores and scales. Then the atlas of those visual scores and scales for dementia was composed of MR images of patients with variable causes of dementia in our institute. Also, we displayed characteristic MR findings in individuals with different diagnosis of dementia.

Result: According to our investigation, the visual scores and scales which were widely accepted and currently used were GCA-scale for global cortical atrophy, MTA-scale for medial temporal lobe atrophy, Fazekas scale for WM lesions, normal ageing, strategic infarctions, and koedam score for parietal atrophy. MR images showing various structural changes of brain in the patients with Alzheimer's disease, vascular disease (in several forms), dementia with Lewy bodies, frontotemporal lobar degeneration, and normal pressure hydrocephalus in our institute were compiled. Conclusion: This comprehensive exhibition will offer aid in being aware of and practicing various visual scales and score in the field, for standardized assessment of MR images in patients with dementia. In addition, those various structural changes on MR images would help differentiate between the different causes of dementia. Purpose: The purpose of our study was to evaluate the relationship between clinical and immunoserological characteristics and brain MRI findings in patients presenting with neuropsychiatric systemic lupus erythematosus (SLE). Methods: Patients with SLE underwent brain MRI due to neuropsychiatric symptoms and a total of 93 patients were enrolled after exclusion of negative MRI results. Positive results of brain MRI were divided as follows; atrophy, infarction, posterior reversible encephalopathy syndrome (PRES), vasculitis and meningitis. Clinical charactersistics (age of SLE onset, disease duration, nephritis, antiphospholipid syndrome (APS), thrombocytopenia) and immunoserological markers (anti-double-stranded DNA (anti-dsDNA) antibody, anticardiolipin (aCL) antibody, C3 and C4) were correlated with brain MRI results

Result: The patients with features of PRES on brain MRI had younger age of SLE onset (17.7± 8.62, p=.03). The disease duration was not different among patient groups. Patients with nephritis had infarction and PRES more often than the others (p=.0272 and p=0.0006, respectively). Patients with APS had infarction more often than the others (p=.00003). Patients with thrombocytopenia had PRES more often than the others (p=.0017). Patients with negative anti-dsDNA Ab had vasculitis more often than the others (p=.01). Patients with positive aCL Ab had infarction more often than the others (p=.035). Patients with decreased C3 count had PRES more often than the others (p=.028). Conclusion: Brain MRI manifestations including infarction, PRES, and vasculitis in patients with neuropsychiatric SLE had significant relationship with clinical and immuoserological characteristics. Purpose: Acute viral encephalitis syndrome (AES) is commonly seen among hospitalized patients. But radiologic imaging is relatively liitle is reported on nonherpetic encephalitis, Japanese Encephalitis (JE) accounts for approximately one-quarter of cases. Although poor prognostic features for JE have been identified, and guide management, relatively little is reported on the remaining three-quarters of AES cases.So, the purpose of this study is to evaluate the characteristic radiologic findings of nonherpetic viral encephalitis , and to compare diagnostic performance between DWI and conventional MR. Methods: Patient with VE (n = 14) were identified through admission records (22 males; median age, 56 years; age range, 8-79 years) between 2010 and 2015. Nonherpetic VE was defined by fulfilling the clinical acute encephalitis symptoms and having a discharge diagnosis of suspicious viral encephalitis, supported by a CSF cell count <1000 cells/mm3 with a lymphocyte predominance and no positive identification of non-viral pathogens in the CSF or blood. AES patients with suspected viral etiology were classified, based on positive IgM antibody in serum or cerebral spinal fluid, as japanese encephalitis (n = 2), EBV (n=1), Mumps ( n=1), and VZV ( n=1) unknown viral aetiology (n = 9). MR imaging in 14 retrospectively identified patients was evaluated for the imaging patterns and MR scoring according to the involved or predominmant sites . We subclassified graymatter ,white matter, cortical patterns on DWI and MR.

Result: Most common imaging pattern on DWI was white matter ( 7) , cortical (6), gray matter ( 1) , and mixed pattern (3) , but on conventional MR ( T2/FLAIR) was cortical (11), white matter ( 8), gray matter (5) ,and mixed (9) Purpose: To compare thalamus volume and thalamus perfusion in RRMS, SPMS and healthy controls, to investigate the correlation between these measures. Methods: 15 RRMS patients (mean age 32y), 15 SPMS patients (mean age 43 y) and 13 healthy controls () underwent magnetic resonance imaging (MRI) and CT-perfusion with iodine contrast. Voxel-based morphometry was performed to assess thalamus volume in all patients. And CT-perfusion was made to evaluate CBF, CBV, MTT measures. Quantitative results were compared (T-test, Mann-Whitney U test). Result: RRMS, SPMS patients experienced significantly higher thalamus atrophy (p<0.05) compared to healthy controls, but there was no significant difference between both types of MS. Redused perfusion (CBF, CBV) was also observed in MS patients compared to healthy controls (p<0.05) in both thalamus. There were no correlations between blood flow and thalamus volume in any of groups. Conclusion: This study shows that deep grey matter atrophy is more pronounced in SPMS and RRMS patients than in healthy controls, and it is closely connected with cerebral blood perfusion. To understand what is primary, redused perfusion or atrophy, further studies are still needed.

multiple sclerosis,brain perfusion,atrophy Purpose: Intracranial calcifications refer to the deposition of crystalline calcium in the parenchyma at various sites in the brain. The localizations and characteristics of the calcifications are very important indicators for diagnosis and differential diagnosis. Although, MRI has been thought to be the best imaging modality in the central nervous system, there are occasions when a CT scan needs to be obtained to confirm the presence of calcifications suspected on MRI, when they become a critical signs in diagnosis.

Methods: 63-old -female was admitted at Military Medical Academy in Belgrade with symptoms of behavioral changes, several crisis of consciousness in last two months and movement disorders. No history of trauma, infections, malignancy and surgery. We performed first MRI of brain and after that we send patient to brain CT scan. Result: Brain MRI showed bilateral symmetric areas of high signal on T1W, isointense on T2W in globus palidus, head and body of caudate nuclei, putamen, thalami, dentate nuclei, corona radiata and subcortical white matter. T2W GRE magnetic resonance images demonstrated in the same areas low signal. That were calcifications, which were confirmed on CT scan. The whole white matter, were T2W/FLAIR/DWI hyperintense, but may not be related to calcifications. That reflected slowly progressive metabolic brain process. We proposed to do next blood analysis: hormonal status of thyroid and parathyroid gland, TSH, phosphorus and calcium blood test. Hormonal status of thyroid gland and TSH were normal after admitance. Blood tests showed: low blood calcium level ( 0,92 mmol/L, normal 2,14 -2,53 mmol/l ), high blood phosphate level ( 1,76 mmol/L, normal 0,79 -1,42 mmol/L ) with low parathyroid hormone concentration ( 0,6 pmol/L, normal 1,6 -6,9 pmol/L ). This indicates the idiopathic hypoparathyroidism. Conclusion: We conclude that cognitive and neurological deficits commonly occur in patients with chronic hypoparathyroidism and may be pathophysiologically related to the presence of intracranial calcifications.

A computed tomography scan allows earlier diagnosis, with high sensitivity and specificity. Magnetic resonance imaging is not useful, because the signal intensity of calcified lesions varies widely. CT remains the best method in the diagnosis of calcifications in the brain parenchyma. Purpose: Various disease entities can cause oculomotor nerve palsy, such as neoplasm, hemorrhage, infarction, inflammatory disease, vascular aneurysm. These lesions can developed at different sites of brain, brainstem, cistern, Meckel's cave, cavernous sinus, or orbital apex. Among these conditions, the microvascular ischemic injury of nerve is considered in patients who have abruptly developed oculomotor nerve palsy with preserved pupil function. Ischemic neuritis of oculomotor nerve is also clinically suspected in patients who have underlying vascular risk factors such as diabetus mellitus or hypertension. After proper management, dysfunction of extraocular muscles can be recovered in ischemic neuritis of oculomotor nerve. We demonstrate the positive MR findings of patients who were clinically diagnosed with ischemic neuritis of oculomotor nerve. Methods: We reviewed clinical and MRI findings of three patients who were clinically diagnosed with ischemic neuritis of oculomotor nerve. MR angiography and orbit MRI with thin section(coronal images: slice thickness 3mm with no gap, axial images: slice thickness 2mm with 0.2mm gap) were performed for all patients.

Result: MRI exams of three patients revealed subtle swelling with increased T2 weighted signal intensity swelling along affected oculomotor nerve. In postcontrast scan showed strong enhancement along involved nerve. This change of oculomotor nerve was prominently noted at the inferior division of intraorbital segment, orbital apex and cavernous sinus regions. These patients had risk factors of ischemic neuritis such as diabetes mellitus or dyslipidemia or hypertension. All of them were treated with aspirin and steroid and partial or complete recovered oculomotor palsy. Result: Leptomeningeal enhancement with small granulomas were present in 15 patients (88,2%; M:F; 5:10); 12 of them had leptomeningeal form in combination with cranial nerves involvement: in 11 cases optic nerve and chiasm; in 3 cases facial nerve were affected, infudibular involvement was in 6 cases; Robin-Virchow spaces of basal ganglia in 3 cases. Five patients (29,4%; M:F; 0:5) had dural involvement, 4 of them in combination with leptomeningeal granulomas; 2 with parenchymal foci. 8 patients (47%; M:F; 3:5) had non-enhancing parenchymal lesions. Simultaneous dural, parenchymal and leptomeningeal involvement was in one case. Most common neurological symptoms in patients with leptomeningeal involvement were headache (53, 3%), dizziness (40%). Cranial neuropathies correlated with MRI in 30%. Patients with leptomeningeal and parenchymal lesions did not have age or gender prevalence. Patients with dural granulomas were older; female prevalence was found. In follow-up MRI reduction of leptomeningeal enhancement was seen in 5 patients from 6; 2 patients had decrease of parenchymal lesion´s number; 3 patients had reduction in cranial nerves leptomeningeal enhancement; one patient had no changes. One patient who did not receive treatment regarding co-morbidities had worsening on MRI: granulomatous enhancement of cranial nerves and infundibulum became more intense. These data correlated with clinical picture. Conclusion: Most common neurosarcoid´s location is leptomeningeal, mostly in combination with optic nerves, tracts and facial nerves involvement. Follow-up MRI is adequate tool for treatment efficiency assessment but more data collection is necessary. Purpose: Down syndrome (DS) is the most common chromosome abnormality in humans. There are few brain imaging studies of DS in children.

In this study we aimed to analyze the white matter integrity of children with DS compared to controls as is reflected in the diffusion parameters derived from Diffusion Tensor Imaging (DTI). Methods: The study consisted of 10 children with DS (age 2.6±0.69) and 8 healty controls (2.5±0.707). DTI images evaluated with a whole brain voxelwise analysis using tract based spatial statistics (TBSS) and subsequently with a complementary atlas-based, region-of-interest (ROI) analysis. The fractional anisotropy (FA) and MD values were obtained for right cerebral pedicul (cp), bilateral anterior limb of internal capsul (alic), bilateral inferior frontooccipital(ifo) fasciculus (fas) and inferior longitudinal fasciculus (ilf), bilateral minor forceps of corpus callosum (CC), bilateral cingulum ( Purpose: Cerebral iron deposition plays a key role in pathophysiology of neurodegenerative processes. Iron concentrations are elevated in cortical and basal ganglia regions in Alzheimer Disease (AD), indicating a disruption of its homeostasis. Higher iron concentrations in AD may increase the possibility of free iron catalyzing lipid peroxidation leading to cell membrane damage and cell death. The aim of this study is to investigate the correlation of brain iron deposition with the severity of white matter microvascular damage evaluated by means of cerebral perfusion in mild-AD patients. Methods: 18 mild-AD patients evaluated by means of neuropsychological tests were enrolled in the study and compared with 18 aged matched healthy volunteers. Iron concentration was derived from R2* measurements obtained with multi-echo gradient echo sequences (1 mm in-plane resolution, slice thickness 4 mm; TR= 68 ms; TE1=4.9 ms, delta TE = 4.9 ms, 12 echoes) and data were collected from 14 ROI in cortical and subcortical grey matter. Regional Cerebral Blood Flow (CBF) was obtained by means of a pseudocontinuous Arterial Spin Labeling (pCASL) sequence (T2* EPI; TR/TE = 4000/11 ms, 3.5x3.5x6 mm3 resolution; label duration = 1650 ms, post label delay = 1600 ms, background suppression pulses). Vascular damage was also evaluated on conventional images according to Fazekas scale. Result: R2* shows a significant correlation with the severity of white matter microvascular damage in the right frontal cortex (p>0.05) and with Mini Mental State Examination (MMSE; p<0.02) in the left frontal cortex in mild AD group compared to controls. CBF modifications in mild-AD patients shows no significant correlation with MMSE and a significant correlation with vascular damage (p<0.05) in the left lateral orbito-frontal cortex. Moreover a significant decreased CBF was observed in bilateral nucleus caudatus in mild-AD group (p<0,05) compared to controls. Conclusion: Iron concentration positively correlates with the severity of microvascular white matter damage and negatively correlates with CBF in mild-AD patients, indicating that it may be used as biomarkers to evaluate the progression of AD. Quantification of brain metal content and distribution may be a predictive marker for early diagnosis, assessment of treatment strategies or therapeutic target in AD. generated for a ROI-based analysis using the software suite (www.mristudio.org, Johns Hopkins University; JHU) under an IRB protocol. Two neuroradiologists independently scored brain regions as having hyperintense signal or normal signal intensity. The parcellation process consisted of (1) skull-stripping of T2WI utilizing ROI Editor, (2) a normalization process in which skull-stripped images were re-sampled to the same image dimensions as the JHU-MNI "Eve" single subject atlas using DiffeoMap, (3) linear transformation of the patient T2WI using the JHU-MNI T2WI as our subject utilizing an atlas to subject transformation, (4) non-linear transformation using Large Deformation Diffeomorphic Metric Mapping applied to the White Matter Parcellation Map type II, which produced a parcellation map of 130 ROIs for each brain. Readers used a binary score of either normal or abnormal for each brain region. Inter-rater reliability was measured as the percent of the 130 regions on which the readers agreed that a specific region was either normal or abnormal. Result: Overall, the percent agreement for all 62 subjects was 75%. In this preliminary study, the most common regions on which the readers agreed as having abnormal signal intensity were in the corticospinal tract, deep white matter, cerebellar white matter, deep gray matter, and posterior corpus callosum. Conclusion: Inter-reader agreement for classifying brain regions based on an automated parcellation program was generally good. Further evaluation using a larger number of readers is presently being performed to validate exact regions of brain involvement in Krabbe disease. Purpose: Hashimoto thyroiditis is the most common autoimmune disease in humans frequently leading to hypothyroidism. It has been reported that among patients with hypothyroidism receiving biochemically adequate treatment, well-being and cognition performance remain reduced. The aim of the study was to evaluate metabolic changes within the normal appearing brain in patients with Hashimoto disease using MR spectroscopy (MRS) and to correlate MRS measurements with clinical data. Methods: Fifty-five patients with Hashimoto disease (HD) without central nervous system involvement (mean age 43.5yrs) and 30 healthy controls (mean age 42.5yrs) were enrolled in the study. The patients with HD were in the euthyreosis phase (normal TSH level), and were treated with levothyroxine. Only those patients and control subjects who had normal signal intensity of the grey and white matter without evidence of cerebral atrophy were included in our study. The MRS examinations were performed on a 1.5T scanner. Voxels were located in the posterior cingulate gyrus (PCG) and the left parietal white matter (PWM). The NAA/Cr, Cho/Cr and mI/Cr ratios were analyzed. The metabolite ratios and hormonal concentrations (TSH, fT3, fT4) as well as anti-TG and anti-TPO levels were also correlated.

Result: There was a significant (p<0.05) decrease of the NAA/Cr ratios in PCG and PWM in patients with Hashimoto disease compared to the normal subjects. Other metabolite ratios showed no significant differences. We also found significant positive correlations between NAA/Cr ratio in PCG as well as PWM and fT3 level (r= 0.344, p<0.05; r= 0.311, p<0.05, respectively). There was also a significant negative correlation between Cho/Cr ratio in PCG and fT4 level (r = -0.322, p<0.05).

Conclusion: The reduction of NAA/Cr ratios may suggest loss of neuronal activity within normal appearing gray and white matters in patients with Hashimoto disease. MRS could be a sensitive marker of early cerebral metabolic disturbances associated with Hashimoto disease. Our findings suggest that there is a biological link between thyroid dysfunction and cerebral metabolic changes. To the best of our knowledge, this study showing metabolic changes in patients with HD using MRS examinations is the first report in world literature. Purpose: To determine the incidence of brain microbleeds in patients with non-hemorrhagic stroke, their relationship with white matter disease and lacunae, their value as a predictor of new stroke events and their relationship with type of antithrombotic treatment Methods: We retrospectively reviewed 435 unselected consecutive patients with ischemic stroke in our Neurology Unit from January 2013 to May 2014. We excluded all patients without an MRI or with a nondiagnostic MRI due to non-sufficient quality and/or without 2D GRE T2*-weighted images. 258 patients had a diagnostic MRI with GRE T2* sequences. Microbleeds were defined as rounded well-delimited hypointense lesions up to one centimeter in size located within the brain parenchyma. Three independent radiologists classified the number and location of microbleeds, with the anatomical sites being the posterior fossa, deep grey matter and cerebral lobes. The findings were correlated with previous clinical ischemic events and type of treatment (antiplatelet or anticoagulant). Result: The overall incidence of microbleeds in patients with nonhemorrhagic stroke was 24.6%. The incidence of leucoaraiosis and lacunae in microbleed patients was 79% and 77.4%, respectively. In the nonmicrobleed group the respective incidence was 62.1% and 66.8%. A previous clinical ischemic event had been experienced by 31% of the microbleed patients but only 17% of the non-microbleed patients. Antiplatelet therapy had been received by 34% of the microbleed patients and 29% of the non-microbleed patients. However, anticoagulant therapy had been received by 11% of the microbleed patients whereas only 4% of the non-microbleed patients had received anticoagulant therapy Conclusion: Cerebral microbleeds are a biomarker of the incidence and recurrence of ischemic stroke and can play a role in treatment decisions about antiplatelet or anticoagulant therapy Purpose: To describe the pattern of white matter (WM) injury in motor and non-motor brain areas in a group of children with cerebral palsy (CP) due to periventricular leukomalacia (PVL), by means of Diffusion Tensor Imaging (DTI) and to correlate the damage with cognitive and clinical features.

Methods: Twenty-five patients (9 females, mean age yrs 11.8 ±3.1), with a diagnosis of spastic bilateral CP , and 25 healthy children (8 females, mean age yrs 11.8 ±2.8) were included in the study. Participants were classified according to the GMFCS and MACS, respectively as to gross motor and handling skills and IQ was assessed by the age-appropriate Wechsler Scale. All subjects underwent an MR examination on a 3T scanner equipped with a 32-channel coil, including a DTI sequence along 32-non collinear directions and with multiple b-values. Differences in DTI measures, both in terms of significance maps and magnitude, where assessed at voxel-level and ROI-level in the whole brain. Correlations between clinical, cognitive and DTI measures were evaluated.

Result: Voxel-level DTI analysis demonstrated a diffuse WM damage that involved both motor and non-motor areas, including commissural (corpus callosum CC), projective and sensory (optic nerves and chiasm) tracts (Fig1).

The ROI-level analysis demonstrated significant (p< 0.01) differences in FA values at the level of cerebellar peduncles (inferior, middle and superior), cortico-spinal tracts and posterior thalamic radiations, body and splenium of the CC, external capsules, anterior thalamic radiation, superior longitudinal fasciculi and coronae radiatae. The magnitude of FA differences was high (15%< δ FA <30%) in posterior coronae radiatae and thalamic radiations, cinguli, CC and superior cerebellar peduncles. 

08 Brook A. S14.4

138 Nakazawa

EPO:085 Pan M

068 Song CJ EPO:069 Song M EPO

Neuroradiology Department, San Raffaele Scientific Institute, Milan, ITALY, 2 Neuroradiological Academic Unit, UCL Institute of Neurology, London, UNITED KINGDOM Purpose: The mechanisms of stroke in Carotid artery stenosis (CAS) can be thrombo-embolic or haemodynamic, which may not be easy to distinguish in clinical practice. Our aim was to assess potential haemodynamic compromise in CAS, with quantification of cerebral blood flow (CBF) and arterial transit time (ATT) using QUASAR ASL . Methods: 22 patients with CAS enrolled in the ECST-2 (second European Carotid Endarterectomy Trial) with good quality baseline QUASAR ASL data. CAS severity was assessed on the basis of Contrast-Enhanced Magnetic Resonance Angiography. The vascular territories of Anterior Cerebral Artery (ACA), Middle Cerebral Artery (MCA), Posterior Cerebral Artery (PCA), Anterior and Posterior Border-Zones (ABZ, PBZ) were outlined on anatomical images, then transposed to measure CBF and ATT on corresponding maps. ABZ and PBZ angles were measured on functional ATT maps. Spearmann correlation, Kruskal-Wallis and Wilcoxon Signed Rank test were calculated (significant p-values<0.05). Result: Overall, the mean CBF of ACA, MCA, PCA territories was >40ml/min/100g, without significant inter-territorial differences; ACA Purpose: Optic nerve and optic chiasm are best imaged with MRI. The better the MRI protocol the best the result. We propose an overview of different abnormalities of the anterior optic pathways according to clinical data and selected sequences. Methods: Patients (adults and children) presenting with optic nerve and optic chiasm (AOP) impairment (visual loss, visual field alteration papilledema) underwent MRI examination. Among all the examination performed during the last 3 years, we selected those demonstrating abnormalities. MRI was performed on a Philips 3T ingenia. Patients were asked to keep their eyes shut. Protocol associated thin coronal T2 WI (2mm) and T1 post gadolinium FATSAT WI (3 mm ) focused on the AOP and brain 3D FLAIR and 3DT1 post gadolinium study. Complementary sequences such as diffusion, axial FATSAT T1 post gadolinium and T2 WI, PDW axial sequence, SWI or T2 GE, and MRA were added depending on the first images and clinical data. MRI were analyzed by two experts and abnormalities selected according to their shape, signal and location. Result: The most frequent AOP abnormalities described were HS T2, focal enhancement , atrophy, enhancement of the perioptic meningeal sheet. Dilatation of the perioptic CSF layer,compression of the nerve or the chiasm were more seldom. Rare hypertrophic optic chiasm was predominant on children. Purpose: Advanced diffusion MRI models such as Neurite Orientation Dispersion and Density Imaging (NODDI) have been recently developed to overcome DTI limitations. NODDI provides multiple compartmental fractions for a richer description of tissue microstructural properties. In this work we present the use of a single color-coded map to represent the information derived by NODDI. Methods: A two-shell NODDI protocol was implemented on 3T Siemens Skyra (30 directions at b=1000 s/mm2 and 60 directions at b=2000 s/mm2) and 3T Philips Achieva (35 directions at b=711 s/mm² and 60 directions at b=3000 s/mm²) and applied in several clinical contexts including demyelinating disease (i.e. multiple sclerosis, progressive multifocal leukoencephalopathy), tumor (i.e. low-and high-grade gliomas, lymphomas), stroke and toxic/metabolic diseases (i.e. hyperosmolarity injury). Diffusion datasets were fitted to the NODDI model in MATLAB. NODDI decomposes the signal of a voxel in three-compartments: neurites, extra-neurite and isotropic Gaussian diffusion. We created a single RGB color-coded map of the three-compartment model (red for extra-neurite, green for neurites and blue for isotropic Gaussian diffusion), in which the relative contributions of the different microstructural compartments could be easily appreciated. Result: The NODDI color map provides a simple and effective way to visualize the relative weight of each compartment. In multiple sclerosis NODDI color map enables better visual assessment of the underlying microstructural changes in normal appearing white matter as well as within lesions. In brain tumors, the NODDI color map better illustrates the tumor extension and different components within apparently homogeneous lesions on FLAIR: cystic/necrotic and infiltrative tumor 1 Neuroimaging Lab, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, ITALY, 2 Functional Neurorehabilitation Unit, Scientific Institute IRCCS Eugenio Medea, Bosisio Parini, ITALY, 3 Child Psychopathology