key: cord-0045769-k49e9vy6
authors: Inchingolo, Riccardo; Smargiassi, Andrea; Soldati, Gino; Demi, Libertario
title: Lung ultrasound as an extension of medical examination for COVID-19 pneumonia: much more than an imaging technique
date: 2020-06-19
journal: Am J Obstet Gynecol
DOI: 10.1016/j.ajog.2020.06.034
sha: 2cb89c9ffc52489291ce9aff4e9ca4362b148491
doc_id: 45769
cord_uid: k49e9vy6

nan

On April 2020, we reported our experience performing lung ultrasound (LUS) on the first pregnant woman admitted for COVID-19 pneumonia 1 However, this limitation is not very relevant, because lung involvement in COVID-19 is typically patchy, multifocal, peripheral and mainly localized in the postero-lateral sites, as CT-scan clearly demonstrates.

We agree with the statement that vertical artifacts represent simplistically a sort of "image error" generated by the interaction of ultrasounds on porous tissues. However, this interaction generates information, as documented in some our publications. This information does not refer to a specific disease, but rather to estimation of subversion of peripheral airspace geometry of lung, thus generating acoustic traps 3 . This finding must be interpreted on a clinical basis. COVID-19 pneumonia shows multiple and irregular peripheral alterations of lung density and structure, as evident from anatomo-pathological studies.

The authors claim to detect artifacts in intestinal loops and post-pneumonectomy. In our experimental models, we found artifacts in soaked synthetic foams and even in bullous suspensions.

This means that LUS artifacts signal the physical states of the explored surface. They carry information on the density and the distribution of air in a bubbly mean, as is the structure of the lung. Therefore, in our models, vertical artifacts can be documented, with their spectral identity, even in lungs with interstitial disease.

We do not agree with authors' statement that LUS in COVID-19 pneumonia "is limited and can be confusing" 2 . We have always stated that the role of LUS is to identify structural change of the assessable lung surface and, consequently, to support clinical hypotheses.

pneumonia is not pathognomonic, being identifiable in other diseases 2 . However, in an epidemic clinical context and in a pregnant woman, with low pre-test probability of underlying diffuse pulmonary diseases, even non-specific signs can help diagnostic process, especially in the absence of not perfectly reliable naso-pharingeal swabs and serological tests.

Awaiting further studies better explaining the accuracy of LUS in COVID-19 pneumonia, we believe that the categorical statement "ultrasound use [...] must be firmly discouraged" is not appropriate because it cannot express a correct scientific attitude.

The Diagnosis of Pneumonia in a Pregnant Woman with COVID-19 Using Maternal Lung Ultrasound

Diagnosis of COVID-19 pneumonia in pregnant women: 1 can we rely on lung ultrasound?

Artifactual lung ultrasonography: it is a matter of traps, order, and disorder

Title: Lung ultrasound as an extension of medical examination for COVID-19 pneumonia: much more than an imaging technique Statement of Authorship: All authors: Conceptualization, writing-original draft preparation, investigation