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Color vision and contrast sensitivity changes in patient with primary angle closure and primary angle closure
Hennaav Kaur Dhillon1, Parul Ichhpujani1, Uday Pratap Singh Parmar1
1Department of Ophthalmology, Government Medical College, and Hospital, Chandigarh, India.
Oman Journal of Ophthalmology
|November 13, 2025
Summary
Color vision and contrast sensitivity are impaired in patients with primary angle closure (PAC) and primary angle closure glaucoma (PACG). Early screening of these visual parameters is crucial for timely intervention.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Visual Neuroscience
Background:
- Primary angle closure glaucoma (PACG) and primary angle closure (PAC) are significant causes of vision loss.
- Understanding the early functional changes in these conditions is critical for effective management.
Purpose of the Study:
- To evaluate color vision (CV) and contrast sensitivity (CS) in patients with PACG and PAC.
- To compare these visual parameters with age-matched controls.
- To correlate visual changes with optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) data.
Main Methods:
- Color vision assessed using D-15 and Ishihara tests.
- Contrast sensitivity measured with Spaeth Richman Contrast Sensitivity Test (SPARCS) and Pelli Robson tests.
- OCT RNFL and Humphrey visual field testing performed on patients and controls.
Main Results:
- Significant color vision defects, particularly protan and tritan, were observed in both PACG and PAC groups compared to controls.
- A substantial number of patients in both PACG and PAC groups exhibited reduced contrast sensitivity.
- No statistically significant difference in central and peripheral CS was found between PACG and PAC groups.
Conclusions:
- Functional vision deficits in color vision and contrast sensitivity occur even in the early stages of primary angle closure.
- Regular screening of these visual parameters is recommended for early detection and management of PAC and PACG.
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