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Updated: Mar 1, 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
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Astronaut ophthalmic syndrome
Sara R Zwart1, Charles R Gibson2, Jesse F Gregory3
1Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas, USA.
Summary
Astronauts experiencing vision problems in space may have a genetically predisposed condition, "astronaut ophthalmic syndrome," linked to 1-carbon pathway metabolism and oxidative stress.
Area of Science:
- Space Medicine
- Ophthalmology
- Genetics
- Metabolomics
Background:
- Astronauts aboard the International Space Station frequently experience ophthalmic changes, including optic disc edema and globe flattening.
- Elevated plasma concentrations of 1-carbon metabolic pathway metabolites are observed in astronauts with these ophthalmic issues.
Purpose of the Study:
- To investigate the potential genetic underpinnings of metabolite differences observed in astronauts with ophthalmic issues.
- To propose a mechanistic hypothesis for "astronaut ophthalmic syndrome" linking genetics, metabolism, and vision changes.
Main Methods:
- Analysis of plasma metabolite concentrations in astronauts.
- Assessment of genetic factors and B vitamin status as predictors of ophthalmic conditions.
- Development of a mechanistic hypothesis for astronaut ophthalmic syndrome.
Main Results:
- Genetic differences and B vitamin status were significant predictors of ophthalmic issues in astronauts.
- A hypothesis was developed linking 1-carbon pathway genetics to astronaut ophthalmic syndrome.
Conclusions:
- Astronaut ophthalmic syndrome is likely a genetically predisposed condition.
- The syndrome may involve endothelial dysfunction induced by oxidative stress, leading to increased intracranial pressure and optic nerve impingement.
- Further research can elucidate the roles of 1-carbon metabolism, homocysteine, oxidative stress, and endothelial dysfunction in spaceflight-induced ophthalmic changes and related diseases.
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