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Updated: May 29, 2026
09:11
Assessment of Global Ocular Structure Following Spaceflight Using a Micro-Computed Tomography (Micro-CT) Imaging Method
Published on: October 27, 2020
AstroOphthalmology: Basic and Pathophysiological Concepts of Space-Induced Ocular Changes.
Kasra Cheraqpour1, Mansoor Shahriari2, Mahya Ghazi3,4
1Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Eye and Brain
|May 28, 2026
Summary
Spaceflight poses significant eye health risks due to microgravity and cosmic radiation. These stressors cause oxidative stress and mitochondrial dysfunction, leading to visual impairment and spaceflight-associated neuro-ocular syndrome (SANS).
Area of Science:
- Ophthalmology
- Space Medicine
- Aerospace Medicine
Background:
- Long-duration space missions present significant risks to astronaut eye health.
- Visual dysfunction is a primary health concern for astronauts.
- This review integrates current insights into the pathophysiological consequences of the space environment on the eye.
Purpose of the Study:
- To review the effects of space on the eye, focusing on pathophysiology.
- To identify key space-specific stressors and their impact on ocular tissues.
- To summarize current in-flight evaluations and suggest future research directions.
Main Methods:
- Literature review of existing studies on spaceflight and ocular health.
- Analysis of pathophysiological mechanisms induced by microgravity and cosmic radiation.
- Summary of current in-flight ocular evaluation techniques.
Main Results:
- Microgravity causes fluid shifts, leading to vascular congestion, altered hemodynamics, and increased intracranial pressure, contributing to spaceflight-associated neuro-ocular syndrome (SANS).
- Cosmic radiation increases the risk of cataracts, retinal cotton-wool spots, and optic neuropathy.
- Ocular damage is a result of synergistic interactions between fluid shifts and radiation, impacting cellular components and ocular tissue function.
Conclusions:
- Spaceflight-induced ocular damage is multifactorial, involving microgravity and cosmic radiation.
- Current in-flight evaluations include optical coherence tomography and fundoscopy.
- Future research must prioritize combined countermeasures and predictive biomarkers for lunar and Martian missions.
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