New evidence released Tuesday documented so-called nodules in the eyes of patients battling severe COVID-19, with scientists hypothesizing causes like virus-related inflammation and positioning patients face down to improve oxygenation.
A team of French researchers published findings in the Radiology journal, drawing on 129 patients with severe COVID-19 who had brain MRIs across 16 hospitals from March 4 to May 1. Nine patients, or 7%, had at least one so-called “hyperintense nodule” toward the back of the eye in the “macular region,” key for clear vision. Nearly all patients in the small subset had nodules in both eyes.
It is still unclear exactly what causes the nodules, though scientists suggested virus-related inflammation or the prone position (when patients are placed face down for better oxygenation) for an extended period. Seven of the nine patients were in the prone position, and researchers therefore hypothesized issues related to “inadequate drainage of the veins of the eyes.”
The team is following up with patients to check for any vision loss, and have since started another study in mild-to-moderate COVID-19 patients to see if the issue affects these patients too.
Six of the patients in the study were obese, two had diabetes and two had hypertension, study authors said. Eight patients underwent intensive care due to their severe bout of COVID-19. Six patients had brain MRIs done because they were slow to wake after sedation was stopped.
“We showed that a few patients with severe COVID-19 from the French COVID-19 cohort had one or several nodules of the posterior pole of the globe,” Dr. Augustin Lecler, study lead author and associate professor at the University of Paris and neuroradiologist from the Department of Neuroradiology at the Foundation Adolphe de Rothschild Hospital in Paris, said in a related release. “This is the first time these findings have been described using MRI.”
The study authors suggested screenings may help in managing these potentially serious manifestations affecting the eyes.
The study had several limitations, like lack of a control group and samples testing for SARS-CoV-2 in the eyes and conjunctiva, or the membrane covering the eye and eyelids. Due to these limitations, the scientists wrote, in part, “it is impossible to assess the direct causality of the virus in our findings.”