key: cord-0950816-vjlvftzv authors: Fotiadou, Aggeliki; Tsiptsios, Dimitrios; Mavraki, Eleni; Psatha, Evlampia A.; Iliopoulos, Ioannis title: Cerebral venous thrombosis: an unexpected Brissaud-Sicard syndrome mimicker date: 2022-03-14 journal: Neurol Sci DOI: 10.1007/s10072-022-05977-1 sha: 96c6a74991db8e4ea18a28ccd74643358ecc307c doc_id: 950816 cord_uid: vjlvftzv nan A 55-year-old male presented to our emergency department with a 24-h history of new onset headache and altered level of consciousness (GCS 11/15). His past medical history was unremarkable. Recent COVID-19 infection or vaccination was not mentioned. He was afebrile with no signs of meningeal irritation. Neurological examination revealed right HFS not accompanied by facial paresis or diminished corneal reflex and contralateral hemiparesis (MRC grade 3/5) alongside brisk tendon reflexes (+ 3) and Babinski's sign. Sensory examination including light touch, pinprick, vibration, and proprioception was unremarkable. Due to the fact that BSS was suspected, urgent brain MRI was performed in order to trace relevant pontine pathology. Interestingly, an extensive right cerebral hemorrhagic infarct sparing brainstem secondary to transverse, sigmoid sinus, and internal jugular vein thrombosis was imaged (Fig. 1) . Thus, the patient was diagnosed with cerebral venous thrombosis (CVT). In an attempt to exclude epilepsia partialis continua causing right facial cramps urgent EEG was also ordered, but did not reveal epileptiform activity. Lower extremities' venous ultrasound was unremarkable. Hypercoagulable workup including homocysteine, antithrombin III, protein C, and protein S deficiency; lupus anticoagulant, antiphospholipid, and anticardiolipin antibodies; factor V Leiden gene mutation and resistance to activated protein C; and prothrombin G20210A mutation was negative. Tumor markers (CA 125, CA 15.3, CEA, PSA), thorax, and abdominal CT scans were negative. Blood testing for autoimmune rheumatologic diseases (RF, C3, C4, pANCA, cANCA, ANA), serum protein electrophoresis, and immunofixation were also normal. HFS did not respond to treatment with either carbamazepine or levetiracetam. Anticoagulant treatment, initially with therapeutic dose of tinzaparin (14,000 IU daily) and oral warfarin afterwards, was commenced. On 3-month follow-up, the patient's symptoms, including HFS, were fully resolved. We present a rare case of BSS mimicker due to CVT resulting in extensive right cerebral hemorrhagic infarct able to explain contralateral hemiparesis, but not ipsilateral HFS. HFS is most often due to aberrant/ectatic blood vessels in the posterior cranial fossa causing facial nerve root exit zone (FNREZ) compression. Offending vessels in descending frequency are the anterior inferior cerebellar artery, posterior inferior cerebellar artery, and vestibular artery. Dual compression of FNREZ by arteries and veins is mentioned; however, HFS caused solely by a venous offender is extremely rare, as only few cases associated with brainstem developmental venous anomaly [3] and a single case of HFS related to straight sinus occlusion in a 10-month infant [4] are mentioned. Congested and dilatated brainstem veins lying in close proximity to the FNREZ could be the irritants. Such is the vein of the middle cerebellar peduncle that successively drains into the superior petrosal vein, the superior petrosal sinus, and the transverse sinus, the latter being thrombosed in our case [5] . To our knowledge, this is the first case report of a patient presenting with BSS semiology related to CVT and not intristic pontine pathology. Moreover, it constitutes the first reported case of HFS complicating CVT in adults. The online version contains supplementary material available at https:// doi. org/ 10. 1007/ s10072-022-05977-1. Ethical approval All procedures performed in the studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Informed consent Informed consent was obtained from the patient. The authors declare no competing interests. Brissaud-Sicard syndrome caused by a diffuse brainstem glioma A rare differential diagnosis of hemifacial spasm Klassische alternierende Syndrome der Brücke Eine historisch-kritische und topodiagnostische Analyse Hemifacial spasm caused by the brainstem developmental venous anomaly: a case report and review of the literature Hemifacial spasm in infancy Bridging veins and veins of the brainstem in microvascular decompression surgery for trigeminal neuralgia and hemifacial spasm Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations