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Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
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Change in intraocular pressure during scleral depression
Richard Trevino1, Brandi Stewart1
1Rosenberg School of Optometry, University of the Incarnate Word, 9725 Datapoint Drive, San Antonio, TX 78229, United States.
Journal of Optometry
|December 3, 2014
Summary
Scleral depression in routine eye exams causes significant intraocular pressure (IOP) spikes, potentially affecting ocular perfusion. Further research is needed to understand the long-term effects of this common clinical practice.
Area of Science:
- Ophthalmology
- Ocular Physiology
Background:
- Scleral depression during eye exams is common.
- Previous studies show significant intraocular pressure (IOP) increases during surgical scleral depression (116-350 mmHg).
- Data on IOP changes during routine clinical scleral depression is lacking.
Purpose of the Study:
- To quantify IOP changes during routine clinical scleral depression in normal eyes.
- To assess the impact of scleral depression on IOP in a non-surgical setting.
Main Methods:
- 28 normal eyes from 28 subjects were analyzed.
- Tono-Pen tonometry was used to measure IOP.
- Scleral depression was performed in the superotemporal (ST) and inferonasal (IN) quadrants, with IOP measured post-procedure for each quadrant.
Main Results:
- Mean IOP during scleral depression was 65.3 mmHg (ST) and 47.8 mmHg (IN), with a maximum of 88 mmHg.
- Mean IOP increase was 51.9 mmHg (ST, right) and 46.4 mmHg (ST, left).
- Mean IOP increase was 45.3 mmHg (IN, right) and 16.8 mmHg (IN, left).
Conclusions:
- Routine scleral depression causes substantial IOP fluctuations.
- These IOP changes may compromise ocular perfusion.
- Long-term consequences of routine scleral depression require further investigation.
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