Astronauts returning from extended space missions are reported to experience significant changes in eye health, linked to prolonged exposure to microgravity. Researchers have identified that altered blood flow and space pressure conditions can lead to vision problems. These changes are mainly associated with a condition called neuro-ococular syndrome associated with space flight (Sans), affecting about 70 % of astronauts during stays of six to twelve months International Space Station (ISS). This raises possible challenges for longer missions, like a journey to Mars.
The study identifies the main eye changes
According to to study published in IEEE Open Journal of Engineering in Medicine and Biology, three critical eye parameters were analyzed: eye rigidity, intraocular pressure and ocular pulse amplitude. The measurements were performed in data from 13 astronauts, whose missions lasted 157 to 186 days. Researchers observed a 33 % reduction in eye stiffness, 11 % decrease in intraocular pressure and a 25 % decline in ocular pulse amplitude. These findings indicate biomechanical changes in the eye, accompanied by symptoms such as small eye size, optic nerve swelling and retinal folds.
Potential Long Term Effects
Dr. Santiago Costantino, Ophthalmologist at the Université de Montreal, highlighted Phys.org, that microgravity alters blood flow and venous circulation in the eye, potentially leading to structural changes in sclera and choroid. The observed changes may persist, raising concerns about the impact on the missions that exceed one year. While most astronauts studied returned to normal vision after their missions, corrective lenses were needed during recovery.
Mars Missions represent new risks
Experts remain cautious about the unknown implications of prolonged exposure to microgravity during prolonged missions like Mars. The research team emphasized that additional studies and preventive strategies are essential to addressing these risks. The findings serve as initial indicators to identify astronauts at risk, paving the way for more targeted solutions to ensure the safety of Spatial exploration Next border.