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Comparing retinal sensitivities on blue-on-yellow and green-on-yellow perimetry in glaucoma suspects
Upasana Pokal1, N Swathi1, A R Rajalakshmi1
1Department of Ophthalmology, Mahatma Gandhi Medical College and Research Institute, Sri Balaji Vidyapeeth University, Puducherry, India.
Indian Journal of Ophthalmology
|October 3, 2022
Summary
Blue-on-yellow perimetry (BYP) and green-on-yellow perimetry (GYP) show good agreement for glaucoma suspects. GYP demonstrated higher sensitivity and specificity in detecting perimetric changes suggestive of glaucoma compared to BYP.
Area of Science:
- Ophthalmology
- Visual field testing
- Glaucoma diagnostics
Background:
- Glaucoma diagnosis relies on detecting subtle visual field defects.
- Short-wavelength automated perimetry (SWAP), also known as blue-on-yellow perimetry (BYP), is a visual field test sensitive to early glaucomatous damage.
- Green-on-yellow perimetry (GYP) is another visual field test that may offer diagnostic advantages.
Purpose of the Study:
- To compare the diagnostic performance of blue-on-yellow perimetry (BYP/SWAP) and green-on-yellow perimetry (GYP) in identifying glaucoma suspects.
- To evaluate the agreement between BYP and GYP in patients with varying degrees of nuclear sclerosis.
- To assess the sensitivity and specificity of GYP relative to BYP in detecting glaucomatous visual field defects.
Main Methods:
- A cohort of glaucoma suspects underwent both BYP and GYP visual field testing after a comprehensive ophthalmic examination.
- Visual field parameters, including mean retinal sensitivity, mean defect, pattern standard deviation, and foveal threshold, were recorded and compared between the two perimetric methods.
- Bland-Altman analysis was used to assess the agreement between BYP and GYP parameters.
Main Results:
- Fifty-five eyes from 39 patients were analyzed, including eyes with clear lenses, pseudophakia, and varying grades of nuclear sclerosis.
- No statistically significant difference was found in mean retinal sensitivity between BYP (22.08 ± 5.02 dB) and GYP (23.84 ± 5.50 dB) (p = 0.08).
- GYP demonstrated high sensitivity (92.86%) and specificity (95.12%) in identifying eyes with perimetric changes suggestive of glaucoma when compared to BYP.
Conclusions:
- Blue-on-yellow perimetry (BYP) and green-on-yellow perimetry (GYP) exhibit good agreement and are comparable across different grades of nuclear sclerosis.
- Green-on-yellow perimetry (GYP) offers superior sensitivity and specificity for detecting glaucomatous visual field defects compared to BYP.
- Both perimetric techniques are valuable tools in the comprehensive evaluation of glaucoma suspects.
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