A study has discovered eye abnormalities in a small group of severe coronavirus patients after a systematic review of brain MRI scans performed during their treatment.

Researchers analysed the ocular MRI scans of 129 patients who were being treated for acute Covid-19 between the 4th of March and 1st of May 2020. Within this group, 7% had one or more hyperintense nodules in the macular region of the eye.

Although researchers don't know the exact cause of the nodules, it's possible that they could be linked to inflammation caused by the virus. Another theory is that the nodules could have been caused by the prone position itself as all of the affected patients in the study had been lying on their stomachs when in an intensive care.

The lead author of the study, Dr. Augustin Lecler from the University of Paris, says, "We did not think that we would discover any ophthalmological abnormalities, since ophthalmic involvement related to Covid-19 is very rare. Rapidly, we found these intriguing nodules of the posterior pole of the globe [the eyeball] which were visible only in the most severe patients: those placed in the prone position, intubated on high-flow supplemental oxygen, and sedated."

There may be many other patients who have these nodules, but because the focus was rightly on monitoring and managing the most urgent symptoms during their time in intensive care, these patients were not subjected to these other precise tests that would give us a deeper insight.

As with other newly discovered potential side effects of Covid-19, the long-term risks are still being assessed.

Sources:

1. RSNA.
2. AOP.
3. Health.com.
4. Healthline.
5. Webmd.