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Trabecular Meshwork Response to Pressure Elevation in the Living Human Eye
Published on: June 20, 2015
Technical note: a comparison of central and peripheral intraocular pressure using rebound tonometry
A Queirós1, J M González-Méijome, P Fernandes
1Department of Physics (Optometry), School of Sciences, University of Minho, Braga, Portugal.
Summary
Peripheral intraocular pressure (IOP) measurements using rebound tonometry show good agreement with central readings. Nasal and temporal IOP measurements are reliable alternatives when central readings are not feasible.
Area of Science:
- Ophthalmology
- Biomedical Engineering
Background:
- Intraocular pressure (IOP) is a critical metric in diagnosing and managing glaucoma.
- Rebound tonometry offers a non-invasive method for IOP measurement.
- Accurate IOP assessment is vital for effective ocular health monitoring.
Purpose of the Study:
- To evaluate the correlation between central and peripheral intraocular pressure (IOP) readings obtained via rebound tonometry.
- To determine the reliability of peripheral IOP measurements in comparison to central measurements.
Main Methods:
- Utilized the ICare rebound tonometer to measure IOP in 153 adult patients.
- Recorded IOP at the corneal center, and 2 mm nasal and temporal to the limbus.
- Analyzed data for differences and correlations between central and peripheral IOP readings.
Main Results:
- Peripheral IOP readings were slightly lower on average than central readings (nasal: 0.75 mmHg lower, temporal: 0.37 mmHg lower).
- Highly significant correlations were observed between central and peripheral measurements (nasal r²=0.905, temporal r²=0.879).
- Approximately 80% of patients had nasal IOP values within +/-1 mmHg of the central reading.
Conclusions:
- Peripheral IOP measurements using rebound tonometry, particularly in the nasal region, are highly correlated with central readings.
- Both nasal and temporal peripheral IOP measurements provide a reliable estimate of central IOP.
- Peripheral readings serve as a valuable alternative for IOP assessment when central measurements are unobtainable.
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