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Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
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High Altitude-associated Changes in Intraocular Pressure Abrogated by Trabeculectomy
William Foulsham1, Andrew J Tatham
1*Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Boston, MA †Princess Alexandra Eye Pavilion, Department of Ophthalmology, University of Edinburgh, Edinburgh, UK.
Journal of Glaucoma
|July 4, 2017
Summary
High altitude ascent increased intraocular pressure (IOP) in an untreated glaucoma eye, but not in a trabeculectomized eye. This suggests filtration surgery may protect against altitude-related IOP changes.
Area of Science:
- Ophthalmology
- Altitude Medicine
- Glaucoma Research
Background:
- Primary open-angle glaucoma (POAG) requires consistent intraocular pressure (IOP) monitoring.
- High altitude environments pose unique physiological challenges, potentially affecting ocular health.
- Previous intraocular surgery, like trabeculectomy, may alter ocular responses to environmental stressors.
Observation:
- A case report details a 66-year-old mountaineer with POAG and a history of trabeculectomy in one eye.
- The patient utilized self-tonometry with a rebound tonometer (Icare HOME) during a Himalayan expedition.
- Measurements were taken before and during ascent to 5000 meters.
Findings:
- The non-operated eye exhibited a statistically significant IOP increase with altitude (1.73 mm Hg per 1000 m).
- The trabeculectomized eye showed no significant IOP elevation during ascent.
- Correlation coefficients and p-values (R=0.790, P=0.001 for non-operated; R=0.219, P=0.172 for operated) support these observations.
Implications:
- Trabeculectomy may offer protection against significant IOP fluctuations at high altitudes.
- Self-tonometry is a valuable tool for remote IOP monitoring in glaucoma patients.
- Findings suggest careful consideration of glaucoma management for individuals ascending to high altitudes, especially those with prior ocular surgery.
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