Seven percent of patients in the small study, conducted in France, had evidence of nodules, or abnormal tissue growth, in the macula of the eye, which is the area responsible for central vision.
Eight of the nine patients required treatment in a hospital intensive care unit for COVID-19 and eight also had nodules on both eyes, the data showed.
“We showed that a few patients with severe COVID-19 … had one or several nodules of the posterior pole of the globe,” study co-author Dr. Augustin Lecler said in a press release.
“Our study advocates for screening of all patients hospitalized in the ICU for severe COVID-19 [and] we believe those patients should receive specific eye-protective treatments,” said Lecler, a neuroradiologist at the Foundation Adolphe de Rothschild Hospital in Paris.
Although the coronavirus primarily attacks the lungs, it has been linked with eye abnormalities such as conjunctivitis, or “pink eye,” and retinopathy, a disease that causes a loss of vision.
Using brain magnetic resonance imaging, Lecler and his colleagues evaluated 129 patients hospitalized with severe COVID-19.
Of these patients, nine, or 7%, had abnormal MRI findings of the globe, or eyeball, with all showing one or more nodules on the back part of the eye.
All nine patients had nodules in the macular region and eight had nodules in both eyes, suggesting that they may experience vision loss.
Of the patients with eye nodules, two of the nine diabetes, six of the nine were obese and two of the nine had high blood pressure before contracting COVID-19.
How these nodules form in the eyes of those with the disease remains unknown, though it could be related to inflammation triggered by the virus, the researchers said.
Inadequate drainage of veins in the eyes, a problem found in patients who spend time in the ICU, also may be a factor. Seven of the nine patients with eye abnormalities had been placed in a prone position — lying on their stomach — in the ICU for an extended time.
These severe eye problems might go unnoticed in the hospital, as COVID-19 patients often are being treated for much more severe, life-threatening conditions, Lecler said.
The findings support eye screening for COVID-19 patients to provide appropriate treatment and management of potentially severe eye symptoms related to the virus, according to the researchers.
The research team is conducting follow-up clinical and MRI examinations in the nine patients, all of whom survived their battle with the virus, to determine whether they have experienced vision loss.
They also are performing MRI examinations on new patients with severe COVID-19 from the second and third waves of the pandemic in France.
“We have launched a prospective study with dedicated high-resolution MR images for exploring the eye and orbit in patients with light to moderate COVID-19,” Lecler said.
“Therefore, we will be able to know whether our findings were specific to severe COVID patients or not,” he said.