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Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
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IOP elevation reduces Schlemm's canal cross-sectional area.
Larry Kagemann1, Bo Wang, Gadi Wollstein
1Department of Ophthalmology, UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
Investigative Ophthalmology & Visual Science
|February 15, 2014
Summary
Acute intraocular pressure (IOP) elevation significantly reduces Schlemm's canal cross-sectional area (SC-CSA) in healthy eyes. This dynamic response may aid in glaucoma management.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Ocular Imaging
Background:
- Previous studies showed reduced Schlemm's canal cross-sectional area (SC-CSA) with increased perfusion pressure in cadaveric models.
- Understanding SC-CSA's response to intraocular pressure (IOP) is crucial for glaucoma management.
Purpose of the Study:
- To determine the effect of acute IOP elevation on SC-CSA in living human eyes.
- To investigate the dynamic changes in SC-CSA in response to IOP fluctuations.
Main Methods:
- Spectral-domain optical coherence tomography (SD-OCT) was used to image the temporal limbus of 27 healthy eyes.
- Intraocular pressure (IOP) was elevated using an ophthalmodynamometer and measured with Goldmann applanation tonometry.
- Schlemm's canal cross-sectional area (SC-CSA) was measured at baseline and during IOP elevation using ImageJ software.
Main Results:
- A mean IOP increase of 189% resulted in a significant mean SC-CSA decrease of 32% (P < 0.001).
- The estimated SC-CSA response to IOP change was -66.6 μm²/mm Hg.
Conclusions:
- Acute IOP elevation significantly reduces SC-CSA in healthy eyes.
- The acute dynamic response of SC-CSA to IOP elevation could be a valuable tool for characterizing ocular health and managing glaucoma.
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