Neurologic Involvement of Patients with Coronavirus Disease 2019: Making the Most of MRI.

Abstract

HomeRadiologyVol. 297, No. 1 PreviousNext CommunicationsFree AccessLetters to the EditorNeurologic Involvement of Patients with Coronavirus Disease 2019: Making the Most of MRIYvonne Purcell , Augustin Lecler, Edouard Saragoussi, Emilie Poiron, Guillaume Poillon, Julien SavatovskyYvonne Purcell , Augustin Lecler, Edouard Saragoussi, Emilie Poiron, Guillaume Poillon, Julien SavatovskyAuthor AffiliationsDepartment of Radiology, Fondation Ophtalmologique Adolphe de Rothschild, 29 rue Manin, Paris 75019, Francee-mail: [email protected]Yvonne Purcell Augustin LeclerEdouard SaragoussiEmilie PoironGuillaume PoillonJulien SavatovskyPublished Online:Jun 9 2020https://doi.org/10.1148/radiol.2020202466MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Editor:We read with interest the recent article by Dr Mahammedi and colleagues (1) describing a spectrum of neuroimaging features of patients positive for coronavirus disease 2019 (COVID-19) at CT and MRI. There was a pressing need for a useful study such as this that reported on the largest patient population to date with neurologic symptoms because of COVID-19. None of their cases showed abnormal parenchymal or leptomeningeal enhancement, although half (10 of 20) of the patients who underwent brain MRI also underwent postcontrast agent–enhanced imaging.However, Helms et al (2) reported leptomeningeal enhancement on MRI in 62% of their patients. Critically, Helms et al performed both three-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) and 3D T1-weighted sequences after injection of gadolinium chelate. In their supplemental figures (2), foci of abnormal leptomeningeal enhancement were most clearly demonstrated on the contrast-enhanced FLAIR sequence rather than the noncontrast-enhanced FLAIR or T1-weighted postcontrast sequences.In our practice, leptomeningeal enhancement appears to be a common feature in patients with COVID-19 with neurologic symptoms. We noticed that such abnormalities are usually not visible by using CT alone, noncontrast-enhanced brain MRI, or even after gadolinium chelate–enhanced 3D T1-weighted imaging. Conversely, adding a contrast-enhanced 3D FLAIR sequence for patients suspected of having COVID-19 improves the conspicuity of abnormalities in the leptomeningeal compartment.The value of contrast-enhanced FLAIR for the detection of leptomeningeal enhancement is well established and considered up to fourfold more sensitive than T1-weighted imaging in detecting low concentrations of contrast agent in cerebrospinal fluid (3). This superiority has been demonstrated in diseases such as meningeal carcinomatosis (4) and Susac syndrome (5). Furthermore, performing 3D FLAIR allows for good suppression of CSF in healthy areas, increasing the contrast with potential leptomeningeal abnormalities.We hypothesize that the low rate of leptomeningeal abnormalities in the study by Dr Mahammedi and colleagues may be because of the lack of contrast-enhanced FLAIR sequence, which is not the standard of care in many institutions.In conclusion, we advocate the integration of a contrast-enhanced 3D FLAIR sequence to brain MRI protocols for the investigation of COVID-19 patients presenting with any neurologic symptom, including confusion and headaches.Disclosures of Conflicts of Interest: Y.P. disclosed no relevant relationships. A.L. disclosed no relevant relationships. E.S. disclosed no relevant relationships. E.P. disclosed no relevant relationships. G.P. disclosed no relevant relationships. J.S. related to the present article: disclosed no relevant relationships. Activities not related to the present article: disclosed payment for lectures from Biogen, Sanofi, Medtronic, and Philips. Other relationships: disclosed no relevant relationships.