Astronauts enjoy huge perks but may suffer the irreversible downside of staying in space – flat eyeballs and cloudy vision.
After spending some time on a space mission, astronauts come home with a cloudy vision that progresses in time and after years of study, researchers have gathered some clues.
The liquid inside the brain gets concentrated in cavities where eyeballs are lodged, irreversibly flattening them.
Nearly 67 percent of astronauts staying at the International Space Station during long space missions suffer from visual impairment intracranial pressure.
This was uncovered after astronaut John Phillips came home from a six-month space mission and underwent a physical examination. His tests reveal that his pre-mission 20/20 vision deteriorated to 20/100. More tests showed that his eyeballs became flat, inflaming the nerves around it.
Noam Alperin who heads the study said that the discovery was alarming, more so because these physical changes are irreversible on earth.
Initially, experts from NASA couldn’t pinpoint exactly what causes this flattening but they held on to the theory that it had something to do with the behavior of body fluids while in space.
While in orbit, more than 60 ounces of body fluid gravitate to an astronaut’s head. According to experts, this causes undue pressure on the brain and the eyes.
A year ago, this phenomenon has been reported by a team of researchers who took vital signs of people who rode the Vomit Comet. Experts discovered that weightlessness decreases intracranial pressure and this runs counter to the earlier theory.
Professor Alperin of the University of Miami said that the concentration of vascular fluid around the brain and eye isn’t the real culprit.
He explained that the cerebrospinal fluid or CSF causes flat eyeballs and impaired vision. CSF acts as a cushion that protects the brain from changes in pressure arising from a change in body position.
His team studied the MRIs of astronauts before and after their long space mission and compared these with those of astronauts who had spent a shorter time in orbit. The first group had higher CSFs in their eye cavities, pushing the eyeballs from the back and flattening its natural curve.
At the moment, there’s no definite action taken to mitigate the damage caused by this syndrome, particularly flat eyeball and impaired vision. However, experts in artificial gravity could lend a hand to solve this and other possible ailments suffered by astronauts coming home from a space mission.