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Comparison of Three Different Tonometers in Eyes with Angle Closure
Tae-Eun Lee1,2, Chungkwon Yoo, Yong Yeon Kim2
1Department of Ophthalmology, Chonbuk National University Medical School and Hospital, Jeonju, South Korea.
The Tono-Pen underestimated intraocular pressure (IOP) in eyes with high IOPs compared to Goldmann applanation tonometry and rebound tonometry. Agreement among tonometers decreased with higher IOP readings in glaucoma patients.
Area of Science:
- Ophthalmology
- Medical Devices
- Glaucoma Research
Background:
- Accurate intraocular pressure (IOP) measurement is critical for diagnosing and managing glaucoma.
- Tonometry devices are used to measure IOP, but their agreement can vary, especially in eyes with elevated pressures.
Purpose of the Study:
- To compare IOP readings from Goldmann applanation tonometer (GAT), rebound tonometer (RT), and Tono-Pen (TP).
- To analyze the agreement among these tonometers in angle-closure eyes with high IOP before and after medical treatment.
Main Methods:
- Twenty-five eyes with angle closure and IOP > 30 mmHg were enrolled.
- IOP was measured using RT, TP, and GAT pre- and post-treatment.
- Bland-Altman analysis assessed agreement among the tonometers.
Main Results:
- Before treatment, TP significantly underestimated IOP compared to GAT (P < .001).
- No significant difference was found between RT and GAT (P = .79).
- After treatment, no significant differences were observed between GAT, RT, and TP (P > .05).
- Measurement error increased with higher IOP readings.
Conclusions:
- TP underestimates IOP in angle-closure eyes with high IOP (> 30 mmHg GAT-IOP).
- Tonometer agreement is reduced in eyes with elevated IOP.
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