Eclipses may be beautiful, but they sure aren't easy on the eyes. Staring at the sun is dangerous at any time, unless you happen to be in the right spot to witness the brief moments of totality, when the moon perfectly covers up most of the sun and the ghostly corona can be seen.
For those who witnessed the Great American Eclipse on Monday and are wondering whether they could have developed vision issues, here are a few things to know about post-eclipse eye health.
First, if you used proper eclipse glasses to view the sun, you should be fine, according to Dr. Avnish Deobhakta, an ophthalmologist at the New York Eye and Ear Infirmary of Mount Sinai. That hasn't stopped some observers from worrying that their vision may be off, however.
Deobhakta, a retinal specialist, said Tuesday that some 15 patients had come in complaining of such post-eclipse issues as blurred vision and light sensitivity. But only a couple of those patients had what appeared to be eclipse-related eye damage, he added.
If you didn't use the glasses, that could be another story. Even glancing at the sun for a few seconds can do significant damage to your retinas, the layer of light-sensitive cells at the back of your eyeball. Specifically, it damages the fovea — the cells in a tiny part of the retina responsible for sharp vision.
"If you're looking at the sun you're actually focusing, intentionally, the light of the sun onto the spot where you want the most precise vision," Deobhakta said of the fovea. "So almost preferentially, everyone gets damage in probably the worst location, which is that part of the retina."
That means any visual activity that involves focusing, such as reading, could potentially be impaired, he said. If you didn't wear proper protection, other possible signs of damage include blurry vision, light sensitivity, or spots or "holes" in your vision.
"In general, damage from the sun to the retina is permanent," Deobhakta said.
There's a similar phenomenon known as laser retinopathy, which often happens when kids shine lasers in people's eyes, he said.
The silver lining is that if you have a solar retinopathy, you'll probably know very shortly after the eclipse, said Dr. Hossein Ameri, an ophthalmologist and a vitreoretinal surgeon at the USC Roski Eye Institute.
"Generally, the symptoms are more severe at the beginning," he said. "And even in permanent cases, they may see a slight improvement, but not significant improvement."
If you looked at the sun without appropriate protection, Ameri recommends seeing an ophthalmologist, who can run a number of tests.
"The longer you look, the more likely the eye gets damaged, that's for sure," Ameri said.
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