Vision Changes on Space Station
When astronauts began to spend six months and more aboard the international space station, they started to notice changes in their vision. For example, many found that, as their mission progressed, they needed stronger reading glasses. Researchers who study this phenomenon have identified swelling in the optical disc, where the optic nerve enters the retina and the flattening of the shape of the eyes. These symptoms have become known as neuro-occurred syndrome associated with space (SAN).
The microgravity causes the displacement of the blood and cerebrospinal fluid of a person and studies have suggested that these fluid changes could be an underlying cause of without. A current investigation, the thigh of the thigh examines if the wrists of the tight legs change the way the liquid moves inside the body, especially around the eyes and in the heart and blood vessels. If this is the case, the wrists could serve as a counterattack against problems associated with fluid offsets, including SAN. A simple and easy -to -use tool to counter the lag towards the head of body fluids could help protect astronauts during future missions to the Moon and Mars. The wrists could also treat the conditions on earth which make the liquid accumulate in the head or upper body, such as rest in bed in the long term and certain diseases.
The survey of fluid offsets, carried out from 2015 to 2020, was the first to reveal changes in the way the blood flows from the brain in microgravity. The alteration of vision and intracranial pressure (VIIP) began to test the role that these liquid changes and an increase in the resulting brain liquid pressure could play in the development of without. This research used a variety of measures, including clinical examinations with and without dilation, imagery of the retina and associated blood vessels and nerves, non -invasive imaging to measure the thickness of retinal structures and magnetic resonance imaging of the eye and optic nerve. In addition, around 300 astronauts have fulfilled questionnaires to document vision changes during their missions.
In an article published from research, scientists described how these imaging techniques have improved the understanding of the SAN. The authors summed up the emerging research on the development of a virtual reality display mounted on the head which can perform a multimodal and non -invasive assessment to help diagnose SANs.
Other researchers have determined that the measurement of the diameter of the optic nerve sheath is promising as a means of identifying and quantifying the changes in the eyes and vision during space flight. The document also makes recommendations to normalize imaging tools, measurement techniques and other aspects of study design.
Another article reported an individual astronaut that had more serious changes than usual after a six -month space flight and certain factors that have contributed. Researchers have also observed an improvement in the symptoms of the individual who could be due to the supplementation of B vitamins and the lower cabin carbon dioxide levels after the departure of certain crew members. Although only one case does not allow researchers to determine the cause and effect, the extent of improvements suggests that this person can be more affected by environmental conditions such as carbon dioxide. This may have been the first attempt to alleviate SAN with vitamin supplementation in flight flight.
Sansori, a CSA (Canadian Space Agency) survey, used an imaging technique called optical consistency tomography to examine whether the reduction in the rigidity of the eye tissue contributes to the SAN. On Earth, changes in rigidity of the fabric around the eyeball have been associated with aging and conditions such as glaucoma and myopia. The researchers found that long -term space flight affected the mechanical properties of eye tissue, which could contribute to the development of Sans. This observation could improve the understanding of eye changes during space flights and in aging patients on earth.
The MHU-8 survey of Jaxa (Japan Aerospace Exploration Agency), which examined the changes in the expression of DNA and genes in mice after a space flight, found changes in the optic nerve and the retinal tissue. Researchers have also found that artificial severity could reduce these changes and could serve as a countermeasure on future missions.
These studies and others could ultimately help researchers prevent, diagnose and process vision disorders in crew members and people on earth.
