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Hypobaric hypoxia: effects on intraocular pressure and corneal thickness
Marcella Nebbioso1, Stefano Fazio1, Dario Di Blasio2
1Department of Sense Organs, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy.
Thescientificworldjournal
|February 20, 2014
Summary
Hypobaric hypoxia (HH) significantly reduces intraocular pressure (IOP) and increases corneal thickness. This study suggests HH enhances aqueous humor outflow through the trabecular meshwork, offering insights into glaucoma mechanisms.
Area of Science:
- Ophthalmology
- Aerospace Medicine
- Physiology
Background:
- Ocular hydrodynamics are crucial for understanding intraocular pressure (IOP) regulation.
- Glaucomatous disease is linked to abnormal IOP and aqueous humor dynamics.
- Hypobaric hypoxia (HH) effects on ocular parameters require further investigation.
Purpose of the Study:
- To investigate the impact of hypobaric hypoxia (HH) on ocular hydrodynamics.
- To elucidate the mechanisms of IOP changes under HH conditions.
- To gain insights relevant to glaucomatous disease management.
Main Methods:
- Twenty male Italian Air Force subjects (32±5 years) were exposed to a hypobaric chamber simulating 18,000 feet.
- Subjects used standard jet pilot oxygen masks and helmets with automatic mixers.
- Intraocular pressure (IOP) and corneal thickness were measured at baseline, during HH, and upon return to sea level.
Main Results:
- Mean IOP decreased significantly from 16±2.23 mmHg at baseline to 13.7±4.17 mmHg at 18,000 feet and 12.8±2.57 mmHg at sea level (P<0.05).
- Corneal thickness showed a statistically significant increase under hypobaric conditions (P<0.05).
Conclusions:
- Hypobaric hypoxia appears to increase aqueous humor (AH) outflow through the trabecular meshwork (TM).
- Observed IOP reduction under HH may be attributed to enhanced AH drainage.
- Findings provide a basis for understanding ocular responses to environmental stress and their implications for glaucoma.
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