posted 02-12-2012 03:15 AM               

In the past few years, about half of the astronauts aboard the international space station have developed an increasing pressure inside their heads, an intracranial pressure that reshapes their optic nerve, causing a significant shift in the eyesight of male astronauts. Doctors call it papilledema.

Female space travelers have not been affected.

Some of the astronauts slowly recover. Others have not.

Space station astronauts typically spend about six months in orbit.

Barratt is one of 10 male astronauts, all older than 45, who have not recovered. Barratt returned from a six-month stint aboard the station in October 2009 and has experienced a profound change in his sight.

He used to be nearsighted. But now, the space veteran says he’s eagle-eyed at long distance but needs glasses for reading. There is no treatment and no answers as to why female space flyers are not affected.

posted 02-12-2012 07:20 AM               

If NASA ever wants to send astronauts to Mars, it first must solve a problem that has nothing to do with rockets or radiation exposure.

A newly discovered eye condition -- found to erode the vision of some astronauts who've spent months aboard the International Space Station -- has doctors worried that future explorers could go blind by the end of long missions, such as a multi-year trip to Mars.

posted 02-12-2012 11:39 AM            

1. Male astronauts going to Mars should not be older than 40 at launch;

2. Male astronauts picked for future Mars missions should have completed a long-duration Earth orbital flight to determine if their eyes are affected by this condition;

3. I doubt if Michael Barratt is complaining too much if he has been rendered "eagle-eyed" for long-distance viewing. A man of his age should expect to be long-sighted and needing reading glasses. Perhaps this suggests that male astronauts who DON'T need reading glasses should take a precautionary pair to Mars, just in case (assuming the problem hasn't been detected as per (2) above;

4. At least one female crew-member should have commanded a space mission and should either take charge, or be trained to be able to take charge, during the re-entry and splashdown phase.

posted 02-13-2012 02:13 AM               

Main thing to keep in mind is although no female astronauts have apparently developed the condition, the ratio of male astronauts to females that have flown 6 month assignments on stations going back to Mir is rather lobsided in favor of the men (Shannon Lucid was the first woman to do a long duration spaceflight on Mir). So just because it hasn't developed in women astronauts sampled doesn't necessarily mean it will not.

posted 02-13-2012 11:34 AM               

quote:

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Originally posted by moorouge:
Isn't this a case of the media being sensationalist once again?

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Yes, there are other biomedical challenges facing humans flying to Mars, but those are understood to the point that countermeasures are being, if not having already been, developed.

This is a problem that is not well understood and for which no countermeasures have been developed as of yet. And it's not just affecting potential future missions to Mars, but crew availability for space station flights now (it was one of the factors that the Astronaut Office used to justify its current 2013 astronaut recruiting effort).

posted 02-14-2012 02:03 AM               

Perhaps NASA should talk to the Navy where vision problems of those serving in nuclear submarines have led to crew members not being allowed to drive for several days when they return to port.

posted 07-09-2016 05:31 PM               

Visual impairment intracranial pressure syndrome (VIIP) is named for the leading theory to explain it. On Earth, gravity pulls bodily fluids down toward the feet. That doesn't happen in space, and it is thought that extra fluid in the skull increases pressure on the brain and the back of the eye...

Here on Earth, the most similar condition is idiopathic intracranial hypertension (IIH). Patients with this condition also have increased pressure in their heads, and they experience visual changes such as those of the astronauts. Another condition, papilledema, involves optic nerve swelling.

But they are not perfect models for the astronauts’ disorder. "Idiopathic" means that no one knows what causes it. It comes with a deluge of other symptoms, including nausea, dizziness and severe headaches, that astronauts with VIIP do not experience. And the medication for papilledema, optic-nerve swelling, does not work on astronauts with VIIP.