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Updated: Aug 9, 2026
09:03
Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
Effect of resisting tonometry on intraocular pressure
K A Frantz1, R J Peters, D M Maino
1Illinois College of Optometry, Chicago 60616.
Journal of the American Optometric Association
|October 1, 1994
Summary
Tonometry in uncooperative patients can yield unreliable intraocular pressure (IOP) readings. Simulated resistance significantly increased IOP measurements, suggesting caution is needed when interpreting results in difficult-to-measure patients.
Area of Science:
- Ophthalmology
- Medical Devices
- Patient Care
Background:
- Tonometry is challenging in children and patients with developmental delay.
- Stressful conditions can compromise the reliability of intraocular pressure (IOP) measurements.
- Factors like increased blood pressure and globe pressure affect IOP in uncooperative patients.
Purpose of the Study:
- To investigate the impact of simulated patient resistance on IOP readings.
- To determine if IOP measurements are significantly altered under conditions mimicking patient uncooperativeness.
Main Methods:
- Intraocular pressure (IOP) was measured using the Tono-Pen in 40 cooperative adults.
- Measurements were taken under both normal conditions and simulated resistant conditions.
Main Results:
- A statistically significant difference (p < 0.001) was found between IOP readings under normal and resistant conditions.
- IOP readings under simulated resistance showed greater variability.
- Average IOP was 6mmHg higher under simulated resistant conditions compared to normal conditions.
Conclusions:
- Caution is advised when interpreting IOP readings from resistant patients.
- False high IOP readings in resistant patients may lead to unnecessary glaucoma evaluations.
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