SANSORI-2: Protecting astronaut eye health in microgravity
The SANSORI-2 experiment will seek to discover the factors involved in vision changes that some astronauts experience on the International Space Station (ISS).
Background
Microgravity is a unique environment and causes astronauts who live and work on the ISS to experience changes to their bodies. One change, experienced by almost 70% of astronauts, is how eyesight can become altered over a long mission.
This condition is called Spaceflight-Associated Neuro-Ocular Syndrome (SANS). Researchers believe SANS could be linked to fluid redistribution in the body due to the low gravity environment. The extra fluid that builds up in the head creates pressure, which affects the astronaut's eyesight.
SANSORI-2 builds on Canadian experiment SANSORI. Canadian researchers will investigate how the eye's mechanical properties affect vision in microgravity.
Objectives
This study will:
- analyze how changes in tension within the eye tissues contribute to SANS
- examine how the eye's blood vessels contract when holding breath or straining and determine if this is a contributing factor to SANS
- study long-term changes in the eye's mechanical properties, especially in astronauts who have had SANS before. This may be a predictor to understand why astronauts who have had SANS are more susceptible to getting it again on future space missions
- increase the number of astronaut participants to acquire a larger data set
Impacts on Earth
Although SANS is a condition that applies specifically to vision changes in space, the knowledge we gained from the first SANSORI experiment has led researchers to better understand vision problems on Earth.
SANSORI-2 will collect more data to better understand and assess eye conditions caused by alterations of blood pressure in the body. Specifically, techniques to assess the symptoms of SANS are similar to those used to assess glaucoma and vice versa. This research can also help us understand the effects of pressure changes in patients' heads and eyes when they are on prolonged bedrest.
How it works
- Researchers will collect data about astronauts' eyesight and the physical properties of their eyes before, during and after their spaceflights. Researchers will:
- use scans of the back of the eye as it deforms, driven by blood flow
- use measurements to assess how the pressure inside the eye changes over time
- analyze changes to the anatomy of the eyeball
- Researchers will use data sharing to access as much information about the astronauts' vision as possible, and to ensure they have a complete picture of the astronauts' medical history.
Researchers plan to gather data from 18 astronauts.
Timeline
SANSORI-2 began in , and scientists will continue to analyze data through .
European Space Agency (ESA) astronaut Alexander Gerst takes optical measurements on board the International Space Station. (Credit: NASA)
Research team
Principal investigator
- Dr. Santiago Costantino, Université de Montréal
Co-investigator
- Dr. Mark Lesk, Université de Montréal