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Updated: Jan 11, 2026

Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
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.
Purpose:
The purpose of the study was to assess color vision (CV) and contrast sensitivity (CS) in patients with primary angle closure glaucoma (PACG) and primary angle closure (PAC) and to correlate these changes with age-matched controls. In addition, to asses this correlation with optical coherence tomography (OCT) retinal nerve fiber layer (RNFL).
Materials And Methods:
CV (using D-15 and Ishihara test) and CS (using Spaeth Richman Contrast Sensitivity Test [SPARCS] and Pelli Robson test) were analyzed in patients with PACG (Group 1) (33 eyes), PAC (Group 2) (27 eyes), and controls (Group 3) (60 eyes). OCT RNFL and Humphrey visual field testing was also done for cases and controls.
Results:
Out of a total of 33 eyes in Group 1, 2 (6%) eyes had no defect, 20 (60.6%) had protan defects, 2 (6%) had deutran defects, and 9 (27.3%) eyes had tritan defects. Of the 27 eyes in Group 2, 1 (3.7%) eye had no CV defect, 19 (70.3%) eyes had protan defects, and 7 (25.9%) eyes had tritan defects. None of the eyes in Group 2 had a deutran defect. Forty-seven (78.3%) eyes from Group 3 had no CV defect, 10 eyes (16.6%) had a protan defect, and 3 (5%) of the eyes showed a tritan defect. All Group 1 and Group 2 eyes had a C-Index of >1.4. Twenty-eight eyes had a total SPARCS score <70, 18 eyes belonged to Group 1, and 10 eyes belonged to Group 2. There was no statistically significant difference in central and peripheral CS (in all the quadrants) between Groups 1 and 2.
Conclusion:
Qualitative and functional vision parameters are affected even in PAC patients before PACG sets in clinically. Hence, early and regular screening of these parameters is required.
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