Eyes in Space, a Good Idea?

Blog vol 5.32. Eyes in Space, a Good Idea?


When it comes to the subject of physics and space, I get really interested. You start talking about eyes and space, watch out. 


You can imagine what I felt when I read the latest issue of the IEEE Open Journal of Engineering in Medicine and Biology,  which had just published an article on the impact of space missions on an astronaut’s eyes!


Prolonged microgravity has a negative effect on the eye and vision. The ocular changes that occur are known as space-flight-associated neuro-ocular syndrome (SANS). It’s postulated that the weightlessness experienced in space causes blood and cerebrospinal fluid (CSF) to travel toward the head (known as the “water-hammer effect”). 


40-70% of astronauts traveling to the International Space Station (ISS) experienced some amount of swelling in the back of the eye.


This swelling can cause optic disc edema, global flattening, choroidal and retinal folds, hyperopic refractive error shifts, and even focal areas of retinal ischemia, i.e. problems.  Throw in individual genetics, metabolism, and nutrition, and these changes in the eye can be quite serious.


The latest research from Canadian Space Agency in Quebec looked at 13 astronauts that were part of long-duration space missions on the ISS. The study looked at ocular rigidity, intraocular pressure, and ocular pulse amplitude. All three findings showed significant changes in the astronauts’ eyes from pre-space:  SANS. In many cases, this shift can be corrected with spectacles during the mission, but some experience significant problems.


The researchers in Quebec have concluded that at-risk astronauts need to be identified in order to prevent exposure and serious damage in a prolonged mission. The good news is that once the astronaut returns to Earth and Earth’s gravity, the eyes return to normal.  The changes are not permanent however debilitating SANS was in space (Read more here).


All very interesting, but it does make you wonder if Buzz Lightyear can make it to infinity and beyond.




The good doctor


By Dr. Mark Germain May 1, 2026
The good doctor discusses how the eye is a window to the heart with the help of the OCT.
The good doctor take a deeper look at how gut health is connected to eye tissues.
By Dr. Mark Germain April 29, 2026
Blog vol 6.40. The Gut and the Eyes. One of my biggest jobs is to keep abreast of new research and advances in eye health. Most recently, we have seen new stem cell research, gene therapies, as well as new drugs for dry and wet macular degeneration. In January of this year, there was an article in the journal, Cell Death and Disease, that looked at cell apoptosis, specifically with the photoreceptors of the eye. (Read the article here ). Apoptosis is the genetic programming of deliberate and constructive cell death, allowing for the maintenance of healthy structures and systems in the body. Some estimates have the body replacing 50 to 70 billion cells daily by this process. Necrosis, on the other hand, is unplanned cell death caused by injury, toxins, or other negative outside factors; this causes inflammation and disrupts the body’s balance of things. There are stressors that speed up cell turnover. The study looked at photoreceptors in the retina and were able to demonstrate cellular recovery, even in late stages of apoptosis, recovery not breakdown. When certain stressors were reduced, by working with the mitochondria, there was recovery of the photoreceptor cells. How? Mitophagy, the mitochondria’s own process of programmed breaking down and then repurposing the recycled components for new ones. This mitochondrial repair helps to reverse the sequence of apoptosis for the photoreceptors. Mitochondria, how cool. How is this helpful for our eyes? Conditions like retinitis pigmentosa or macular degeneration directly involve the photoreceptors and may be slowed or reversed by helping the mitochondria. So, let’s take care of those mitochondria. There is some evidence for nutritional support for the mitochondrial system. The nutrient, Urolithin A (UA), which is a compound made in our gut from fiber found in pomegranates, berries, and nuts is the only clinically proven substance known to trigger mitophagy, made in the gut no less. Vitamin B3 is critical for mitochondria function, however vitamin B3 based supplements are still to be clinically tested for their support of cell recovery. Nutrients Coenzyme Q10 and L-carnitine are known to help the mitochondria generate energy, and interestingly, infrared light therapy has also been shown to benefit mitochondrial function. Again, food for thought. The gut and its function needs a lot of research. How do probiotics and nutrient precursors affect eye tissues? It is so interesting that the gut can be a factor in eye health. Maybe adding Urolithin A as a supplement is wise, along with the antioxidants in Lutein and Zeaxanthin we use to combat photoreceptor degeneration. Will keep you posted on any new developments.  The good doctor
By Dr. Mark Germain April 16, 2026
The good doctor focuses in on visual processing. Why do we miss things that are right in front of our eyes?
By Dr. Mark Germain April 10, 2026
The good doctor discusses the Artemis II mission, space travels affects on the eyes, and "the dark side of the moon"
By Dr. Mark Germain April 3, 2026
The good doctor discusses exciting new and emerging options to treat nystagmus.
By Dr. Mark Germain March 27, 2026
The good doctor reflects on The Country of the Blind, a book by Andrew Leland which gives insight into the experience of vision loss.
More Posts