Too much space travel is hazardous for your eyeballs

By Sarah Kaplan

Something strange has been happening to people who stay too long in space: The backs of their eyeballs start to flatten. Spider-web-like marks called choroidal folds crisscross the thin layer of blood vessels and connective tissue that surround their retinas. Their vision goes blurry, their optic nerves become inflamed. The damage can last long after the astronauts return to Earth. And scientists haven’t been able to explain why.

“People initially didn’t know what to make of it, and by 2010 there was growing concern as it became apparent that some of the astronauts had severe structural changes that were not fully reversible upon return to earth,” notes Noam Alperin, a professor of radiology and biomedical engineering at the University of Miami Miller School of Medicine.

Now Alperin may have found the source of this mysterious syndrome. In a study presented this week at the annual meeting of the Radiological Society of North America, he suggests that the problem might be caused by pressure from the fluid that cushions the brain.

Continue reading by clicking the name of the source below.