Anterior Segment Changes after Laser Iridotomy for the Treatment and Prevention of Angle-closure Glaucoma

Abstract

Purpose: To evaluate the changes and characteristics of the anterior segment of the eye after laser peripheral iridotomy (LPI) conducted on patients with acute angle closure crisis (AACC) for both therapeutic purposes and prophylactic purposes in the fellow eye. Methods: Anterior segments were examined by topography, laser interferometry, anterior segment optical coherence tomography, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), angle opening distance (AOD), central corneal thickness (CCT), and axial length as compared to prior procedures in 20 eyes with glaucoma (treatment group) and 20 contralateral eyes (prophylactic group) in 20 patients diagnosed with AACC. Results: Before laser treatment, there were no significant differences in pre-LPI ACV, ACA, AOD and axial length, although differences in the CCT and ACD existed between the groups. Compared to prior laser treatment at 1 and 3 months after laser treatment, the ACV, ACA, AOD 500, and AOD 750 increased in both groups. When both groups were compared 1 month after their laser treatments, the AOD 750 was increased in the treatment group. There were no significant differences between two groups 3 months post LPI. Conclusions: Other than changes in the ACD and CCT, no significant differences were observed in the anterior segment characteristics in AACC affected and contralateral eyes prior to LPI. After LPI, the treatment group showed greater changes in their anterior segments; however, the open angle was maintained at 1 month post treatment.