Central Retinal Artery Occlusion in Patients with COVID-19: Imaging for Underlying Causes.

Abstract

HomeRadiologyVol. 300, No. 1 PreviousNext CommunicationsFree AccessLetters to the EditorCentral Retinal Artery Occlusion in Patients with COVID-19: Imaging for Underlying CausesSunny Chi Lik Au* , Callie Ka Li Ko†Sunny Chi Lik Au* , Callie Ka Li Ko†Author AffiliationsDepartment of Ophthalmology, Tung Wah Eastern Hospital, 9/F, MO Office, Lo Ka Chow Memorial Ophthalmic Centre, 19 Eastern Hospital Road, Causeway Bay, Hong Kong, HKSAR, ChinaDepartment of Ophthalmology, Tung Wah Eastern Hospital, Hong Konge-mail: [email protected]Sunny Chi Lik Au* Callie Ka Li Ko†Published Online:Mar 30 2021https://doi.org/10.1148/radiol.2021210479MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack Citations ShareShare onFacebookTwitterLinked In Editor:We read with interest the research article published online in Radiology on February 16, 2021, by Dr Lecler and colleagues (1) that discussed hyperintense nodules in the macular region at fluid-attenuated inversion recovery–weighted imaging in patients with COVID-19. We are particularly interested in the central retinal artery occlusion (CRAO) case, which was highlighted by the authors but lacked details regarding whether there was unilateral or bilateral ocular involvement. COVID-19 systemic infection is prone to endothelial insult with vasculitis tendency, in which bilateral CRAO would not be unusual. The section on correlations between MRI and ophthalmologic findings listed features separately without identifiable correlation. We are interested in whether the CRAO case was the same patient having multiple infarcts in the anterior cerebral artery territory, or the one with frontal hematoma, or others.Ocular manifestation of COVID-19 is a hot topic given that the eye is optically clear to allow for direct inspection of the microvascular structures without biopsy. Regarding retinal vascular diseases, only a handful of cases were published on CRAO in patients with COVID-19 (2–6), identified by searches over PubMed, Medline, EMBASE, Scopus, Web of Science, Cochrane library, and Google Scholar with the terms [“central retinal artery occlusion” OR “CRAO”] AND [“COVID” OR “coronavirus”] on February 16th, 2021. Cases reported by Acharya et al (2), Montesel et al (3), and Turedi et al (5) had unremarkable neuroradiologic findings, whereas Murchison et al (4) and Sweid et al (6) mentioned the neuroimaging findings of unilateral internal carotid artery obstruction causing secondary CRAO. The unique case of CRAO at MRI in patients with COVID-19 in the work by Dr Lecler and colleagues was the sixth in the literature, and the third such report with positive radiologic findings.Stroke is associated with COVID-19 because of its hypercoagulability and thromboembolic tendency, yet the evidence is uncertain in CRAO, limited by small number of reported cases. CRAO is a blinding ocular emergency and patients present with acute visual loss. Resultant retina ischemia causes neurosensory retinal edema, thus retinal whitening at ophthalmoscopy. At diffusion-weighted MRI in patients with CRAO, there are some reports of retinal hypersignal diffusion of the papilla or scattered diffusion restriction over the retina. As Dr Lecler and colleagues mentioned, there were no patients with optic nerve abnormalities. We would be interested in whether the patient with CRAO underwent concomitant cerebrovascular stroke or vasculitis features at neuroimaging.Disclosures of Conflicts of Interest: S.C.L.A. disclosed no relevant relationships. C.K.L.K. disclosed no relevant relationships.