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Updated: May 9, 2026
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Assessment of Global Ocular Structure Following Spaceflight Using a Micro-Computed Tomography (Micro-CT) Imaging Method
Published on: October 27, 2020
Optic disc edema in an astronaut after repeat long-duration space flight.
Thomas H Mader1, C Robert Gibson, Anastas F Pass
1Department of Ophthalmology, Alaska Native Medical Center, Anchorage, Alaska 99507, USA. tmader@acsalaska.net
Summary
Astronauts may experience worsening eye conditions after repeat space missions. Previous microgravity exposure may predispose astronauts to new pathological eye changes during subsequent flights.
Area of Science:
- Ophthalmology
- Aerospace Medicine
- Space Physiology
Background:
- Long-duration space flights are associated with various ophthalmic findings in astronauts.
- Previous research indicates optic disc edema, globe flattening, and choroidal folds post-flight.
- This study focuses on an astronaut with pre-existing postflight ophthalmic abnormalities experiencing new changes after a repeat mission.
Observation:
- A case study involving an astronaut with two 6-month exposures to microgravity.
- Comprehensive eye examinations were conducted before and after each mission, including advanced imaging techniques.
- In-flight monitoring was also performed during the second mission.
Findings:
- The astronaut initially presented with unilateral choroidal folds and a cotton wool spot after the first mission.
- During the second mission, the astronaut developed more extensive choroidal folds and new-onset optic disc edema in the same eye.
- These findings indicate a progression of ophthalmic abnormalities.
Implications:
- Microgravity-induced anatomical changes from the first mission may increase susceptibility to further changes.
- Repeat space flight and associated physiological stress can exacerbate pre-existing ophthalmic conditions.
- This highlights the need for continued monitoring of astronaut eye health, especially for those with prior abnormalities.
