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Test retest variability of TonoPen AVIA
Shibal Bhartiya1, Shveta J Bali, Mathew James
1Department of Ophthalmology, Glaucoma Facility, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India, Vision Eye Institute, Chatswood, Australia, .
Indian Journal of Ophthalmology
|March 22, 2013
Summary
The Tonopen AVIA demonstrates excellent intra-session repeatability for measuring intraocular pressure (IOP) in both glaucoma patients and healthy individuals. This device offers reliable IOP readings for clinical use.
Area of Science:
- Ophthalmology
- Medical Devices
- Glaucoma Research
Background:
- Accurate intraocular pressure (IOP) measurement is crucial for glaucoma diagnosis and management.
- The Tonopen AVIA is a widely used handheld tonometer, but its intra-session repeatability requires robust evaluation.
Purpose of the Study:
- To assess the intra-session repeatability of IOP measurements using the Tonopen AVIA.
- To compare the repeatability in glaucoma patients versus healthy controls.
Main Methods:
- An observational study involving 180 eyes from 180 patients (50 with glaucoma, 130 controls).
- Three consecutive IOP measurements were taken using the Tonopen AVIA.
- Intraclass correlation coefficient (ICC) and coefficient of variation were calculated.
Main Results:
- The Tonopen AVIA showed high intra-session repeatability with ICC values ranging from 0.958 to 0.996.
- Coefficients of variation were 3.47% for glaucoma patients and 8.10% for controls, with an overall 6.07%.
- Coefficients of repeatability were 2.96 mmHg (glaucoma), 3.35 mmHg (controls), and 3.24 mmHg (overall).
Conclusions:
- The Tonopen AVIA exhibits good intra-session repeatability for IOP measurements.
- This repeatability is consistent across both glaucomatous and healthy eyes, supporting its clinical utility.
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