Doctors are warning that covid-19 may be capable of causing lingering eye problems. A new study suggests that some people who survive a severe infection can develop growths in the back of their eyes that could lead to vision loss. It is not yet clear how covid-19 might cause these growths, or if people with milder covid-19 are also at risk of this complication.
Researchers at the French Society of Neuroradiology looked at medical records from certain patients with severe covid-19. These patients had all gotten a brain MRI at some point during their illness, which allowed the researchers to look for potential abnormalities in and around the eye.
In total, they looked at data from 129 patients across 16 hospitals who were infected during the first wave of the pandemic in France, between March and May 2020. Nine of these patients (7%) had evidence of nodules around the back of the eyeball, with most having growths on both eyes. Eight patients had also been in the intensive care unit.
There have been occasional reports of people with covid-19 with abnormal test results or health issues related to the eye, such as conjunctivitis (pink eye). But the authors say theirs is the first study to try estimating how commonly this might be happening through MRI data. The findings should be enough to convince doctors to look for potential eye problems in patients with severe illness, they add, especially since they could be hard to spot at first.
“Severe eye problems might largely go unnoticed as these patients are often treated in intensive care units for much more severe, life-threatening conditions,” they wrote in their paper, published Tuesday in the journal Radiology. “Our data support the need for a screening and follow-up of these patients to provide appropriate treatment and improve the management of potentially severe ophthalmological manifestations.”
The results do have their limitations. They can’t conclusively show that having covid-19 led to these eye growths, nor can they explain how it might have happened if the disease was responsible. One theory voiced by the authors is that the infection reached the eyes and directly damaged the retina. Another is that inflammation indirectly caused by infection is the main culprit. It’s even possible that the practice of laying patients on their stomachs (the prone position)—a common intervention that’s been shown to help patients breathe more easily—could have contributed to faulty drainage of veins connected to the eye. Pre-existing circulation problems, common in patients with diabetes, might also be a factor.
The researchers are already working on future studies to better understand these potential complications. This includes proactively studying severe covid-19 patients from more recent waves of the pandemic, which would confirm whether these growths and other eye problems are really the result of the illness and not an earlier, hidden issue. Survivors with these growths are also being tracked to see if they’re at increased risk for long-term vision problems. And the researchers are pursuing a similar study, focusing on patients with mild to moderate covid-19.
“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,” said lead author Augustin Lecler, a radiologist and associate professor at the University of Paris, in a statement released by the Radiological Society of North America, which publishes Radiology. “Therefore, we will be able to know whether our findings were specific to severe COVID patients or not.”