As NASA astronaut Scott Kelly returns to earth today after 340 days in space, and heads in for physical tests in Houston, ophthalmologists here on earth are eager to examine his eyes. “If you go up and stay a long time, many things start happening to the eye,” says Dr. Alex Huang. “The biggest change is microgravity, which is long known to affect other parts of your body: muscles, bones, possibly how the fluid distributes in your body.”

Huang says for the eyes, the prolonged exposure to antigravity can cause nerves to swell, resulting in a range of issues. “Folds appear in a part of the eye called the choroid, your prescription can change, and parts of the retina act as if there isn’t enough oxygen.” Huang says those conditions are exacerbated the longer one stays in space.

Here on earth, eye patients could stand to benefit from the astronaut’s extended stay in space, as doctors gather data about changes to the astronaut’s eyes. Huang is working to finalize a collaboration with NASA right now to study impact of microgravity on the eye over time, hoping to find ways to simulate the conditions on earth to enhance eye treatments.

Stay tuned!

Alex Huang MD/PhD
Assistant Professor
Doheny Eye Center of Pasadena
Department of Ophthalmology
Doheny and Stein Eye Institutes
David Geffen School of Medicine
University of California, Los Angeles