Effect of laser peripheral iridotomy on contrast sensitivity using Spaeth/Richman Contrast Sensitivity test

Laser peripheral iridotomy (LPI) is the current standard of care for primary angle-closure glaucoma. The existing literature lacks evidence regarding the effects of LPI on contrast sensitivity (CS) after the procedure.

This study evaluates central and peripheral CS in patients undergoing LPI using the computer-based, Spaeth/Richman Contrast Sensitivity (SPARCS) test.

We performed a pilot, prospective, interventional cohort study including 30 patients of primary angle-closure suspect (PACS) or primary angle closure (PAC) in both eyes. LPI was performed after a detailed history and clinical examination using standard procedure in all eyes. Intraocular pressure (IOP) and CS testing using SPARCS was performed before, 2 weeks and 3 months after LPI.

Data analyses revealed female predominance (66.67%, 20/30); the mean age of enrolled patients was 49.93 ± 10.43 years, and presenting acuity was 0.02 ± 0.06 (Log of Minimum Angle of Resolution [LogMAR]). The mean vertical cup-to-disc ratio (VCDR), mean deviation (MD in dB) and pattern standard deviation (PSD in dB) were 0.34 ± 0.09, -2.36 ± 1.72 and 2.34 ± 0.81, respectively. There was a statistically significant decrease between the pre- (15.17 ± 3.83 mmHg) and 2 weeks post-LPI (11.70 ± 1.53 mmHg) IOP (p < 0.001). However, CS in the pre- (73.47 ± 9.88) and 3 months post-LPI (75.20 ± 11.98) SPARCS scores did not reveal any statistical difference. The group-wise analysis showed a similar trend between PAC and PACS patients.

LPI does not affect central as well as peripheral CS assessment in patients with the primary angle-closure disease.