THERE IS A MYSTERIOUS SYNDROME THAT HAS BEEN DAMAGING ASTRONAUTS’ EYE SIGHT ON THE ISS

There is a mysterious syndrome that has been damaging astronauts’ eye sight on the International Space Station, causing permanent shortsightedness that remains for months even after they have come back to Earth. The problem is so complex and bad that, two-thirds of the astronauts inform having depreciated eyesight problem after spending some time in the orbit. Now as scientists says that they finally have some answers for this problem and it is not looking good for our predictions of getting to the Mars.

"Nobody is gone two years with exposure to this bad issue, and the concern is that we had have loss of visions that is the most necessary requirement for research," Mr. Dorit Donoviel from the United State of National Space Biomedical Research Institute told The Guardian, "That is disastrous for an astronaut in the space station."

In the start of this year, NASA informed that, something in the space has been creating trouble with its astronauts’ perfect vision, causing long-term weakening to their excellence of vision.

Scott Kelly the astronaut, whose outstanding vision was part of the reason that he was selected to be America’s first astronaut to spend a full year in space station, says he is been force to must wear reading glasses since coming home only for the safety of eyesight .

Astronaut John Phillips, who spent time on the International Space Station (ISS) in year 2005, carried his sudden attacks of blurry vision home with him and through his post-flight physical NASA confirmed that his eyesight had gone from 20/20 to 20/100 within just six months.

NASA suspected that the situation called eyesight weakening inter cranial pressure syndrome was caused by the lack of gravity in the space.

The assumption was that the micro gravity of the ISS was building up the pressure in astronaut’s heads, causing almost 2 liters of cerebrospinal fluid (CSF) to shift towards their head. They say that pressure was blamable for the destruction of eyeballs and exacerbating of optic nerves experiential in returned astronauts, both of which have been related to the onset of shortsightedness.

"On the Earth, gravity pulls bodily fluids down towards the feet. That does not happen in the space, and it is thought that extra fluid in the head increases pressure on the back of the eye (optic nerves) and on the brain as well, Shayla Love informed for The Washington Post.

Now, a team of researchers from the University of Miami United States has conducted the first study to test this idea, and found that something else has been affecting eyesight problems in the astronauts.

The researchers matched before and after brain scans from 7 astronauts who had spent many months in the International Space Station (ISS), and compared these scans to the 9 astronauts who had just made short trips to and from the United State space shuttle, which was discharged in the year 2011. The one of the big difference between the two brain scans data was that the long duration astronauts had expressively more cerebrospinal fluid (CSF) in their skulls as compared to the short-trip astronauts, and the researchers say this is not vascular fluid that is responsible for the shortsightedness.

While under the normal circumstances, cerebrospinal fluid (CSF) is most important for mitigating the brain and spinal cord system, while also allocating nutrients around the body and helping the body to remove waste. It can easily adjust to changes in pressure that our bodies experience when transitioning from lying down to sitting or standing, but in the constant microgravity of space, it starts to falter.

"On earth, the cerebrospinal fluid (CSF) system is built to provide accommodations to these pressure variations, but in the space the system is jumbled by the lack of the attitude related pressure variations," says one of the researchers’ team members, Noam Alperin.

Based on the high resolution orbit and the brain MRI scans taken of their sixteen astronauts, the researcher’s team found that the long stay duration astronauts had far higher orbital cerebrospinal fluid (CSF) volume, cerebrospinal fluid (CSF) pooling around the optic nerves in the part of the head that holds the eyes.

They also had significantly higher ventricular cerebrospinal fluid volume, which means that they had more CSF accruing in the craters of the brain where the fluid is actually produced.

"The research delivers, for the first time, measurable evidence found from short and long stay duration astronauts directing to the major and direct role of the cerebrospinal fluid in the globe distortions seen in the astronauts with eyesight weakening syndrome," according to Alperin. The results of this research were presented at, annual meeting of the ‘Radiological Society’ of North America in Chicago, and have yet to be peer revised, so we have to wait for the outcomes to be simulated by an independent team of researchers before we can know for sure that this is the right answer.

But even if this or NASA's original theory turns out to be more precise, we still have a large problem on our hands. Very few astronauts that have spent more than a full year in the space and astronauts are already facing at least 18 months in the space to get to and from Mars. And that is if they flew home instantaneously after arriving, if we want to think about colonization or lengthy stays on Mars, we are going to have to ponder sightlessness as a potential difficulty.

Right now, there are no solutions to this vision problem and for how to treat or prevent cerebrospinal fluid moving toward brain in the space, and with the brain damage that is also predictable to come from long term space flight, Elon Musk's cautionary that the first Mars migrants should be "ready to die" has never been more striking.