Laser peripheral iridotomy across the spectrum of primary angle closure

BACKGROUND: To study the effectiveness of Nd:YAG laser peripheral iridotomy (LPI) for primary angle closure in Asian Indian patients. METHODS: Retrospective analyses of patients who underwent LPI and completed a minimum follow-up of 2 years. Eyes were classified as primary angle-closure suspects (PACS), primary angle closure (PAC), and primary angle-closure glaucoma (PACG).The indications for LPI, requirement of medication, and subsequent clinical course were studied in each group. RESULTS: 103 eyes of 55 patients were analyzed.The mean (SD) follow-up was 45.6 (2) months. The mean age in women was less than in men (55.7 [8.3] vs. 62.1 [7.8] years).Twenty-seven eyes were classified as PACS, 43 eyes as PAC, and 33 eyes as PACG. After LPI, no eye with PACS progressed to PAC or PACG. Four of 43 eyes (9.3%) with PAC progressed to PACG.Twenty-five of the 33 eyes (75.8%) with PACG did not progress after LPI during the study period. Patients with 2 quadrants of angle closure (risk ratio 12.9). INTERPRETATION: After LPI, the rate of progression from PAC to PACG was less than expected from the reported natural course of the disease, and the majority of eyes with PACG remained stable. LPI appears to alter the natural course of PACS, PAC, and PACG favourably.