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  • Date :
  • 9/4/2011

Space journeys can damage eyes


Researchers at the Alaska Native Medical Center have found that long space journeys can damage the eyes and affect the astronauts' vision.

The team examined more than 300 astronauts in the US space program who served on long and short missions, Reuters reported.

Results showed that about 50 percent of those who had spent six months or more in space experienced new problems with their ability to see objects near to them while in space and for some time after returning to Earth.

They also revealed that around 23 percent of astronauts who spent shorter periods in orbit got problems with their near vision during their missions and after getting home.

The NASA-funded team also did physical exams on seven male astronauts who suffered from vision problems after spending six months in space.

The tests explored several signs of eye stress in astronauts, including a buildup of fluid around the optic nerve, development of folds in the bed of vessels that supply blood to the retina and flattening of the eyeballs.

"It’s very hard for us at this point to define exactly what is causing all of this," said leader of the study Dr. Tom Mader.

”The effects may be due to increased pressure of the fluid surrounding the brain, the result of less gravity than on Earth that fails to drain well back into the body, but the precise mechanism is still unclear,”‌ he added.

NASA is conducting follow-up studies, including research on the International Space Station, to determine the definite mechanism behind the development of vision problems in astronauts.

Researchers will also carry out more sophisticated studies on astronauts such as MRI scans to carefully assess their vision and eye anatomy before and after missions.

Source: presstv.ir

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