A 2-year NASA health study analyzing the decreased visual acuity that astronauts seem to experience as a result of long exposure to microgravity in space is currently underway aboard the International Space Station, according to an Oklahoma Association of Optometric Physicians press release.
A digital eye chart known as the Acuity Pro will be used to measure the astronauts’ visual acuities during the study. The chart was invented by Oklahoma optometrists Dan Bintz, OD, and Jerry Carter, OD, according to the release.
Jerry Carter (left) and Dan Bintz (right)
This is the first experiment to investigate microgravity-induced visual impairment/intracranial pressure or VIIP syndrome. According to NASA, about 20% of astronauts who have flown to the International Space Station have reported some type of vision changes with varying degrees of severity and permanence, the release said.
“Scientists are aware that astronauts have developed vision modifications while in space,” Bintz said in the release. “In the past, this issue has not been able to be addressed until astronauts return to earth. Now, with Acuity Pro, NASA has the ability to monitor visual alterations in real time to determine when changes begin, how they progress and specific astronauts who are affected.”
The Acuity Pro was developed to replace the bulb projector used to check visual acuity. By using a computer, doctors can randomize the eye chart, vary the number of letters shown and perform many functions that bulb projectors do not allow, the release said.
NASA successfully uploaded Acuity Pro to the International Space Station earlier this year and it is now installed on all the laptops there, according to the release.