1336
Spaceflight, particularly prolonged exposure to microgravity, causes significant changes in the structure of the eye, leading to neuroocular syndrome associated with vision impairment in astronauts, according to research by Canadian scientists.
About half of astronauts experience vision problems after returning to Earth, which were previously attributed to increased intracranial pressure in weightlessness. However, the results of an analysis conducted by the University of Montreal have changed these ideas. Studying the structure of the eyes of 13 astronauts before and after the flight, scientists found an 11% decrease in intraocular pressure after returning to Earth, as well as a serious decrease in the rigidity of the eyeball by 33%. Such changes reduce the eye's resistance to deformation.
One important finding was the discovery of a thickening of the choroid, which is likely a result of increased blood flow to the upper body in weightlessness. This leads to a pooling of venous blood in the eyes and an influx of cerebrospinal fluid, which stretches the outer membrane of the eye — scleraAlthough the choroid largely recovers upon return to Earth, changes in the sclera remain, which may affect long-term vision.
These findings are important not only for space medicine, but also for ophthalmology in general. They help to understand the mechanisms of the impact of microgravity on the eyes and potentially develop methods for correcting vision problems. As the researchers note, for flights to Mars in the 2030s, which will last more than two years, predicting and preventing such changes will be critically important, because even the weak gravity of Mars (38% of Earth's) may not completely prevent these complications.
Understanding these changes allows us to develop more effective means of adapting and protecting astronauts on long-duration space missions, which is key to successfully exploring distant planets and overcoming the challenges of the space environment.
Scientists Learn Why Weightlessness Spoils Astronauts' Vision appeared first on Curiosity.
