Re-Elevation of Intraocular Pressure after Peripheral Laser Iridotomy in Patients with Closed Angle

ABSTRACT

PURPOSE: To investigate the long-term effects of maintenance of intraocular pressure (IOP) after peripheral laser iridotomy (PLI) in patients with closed angle. METHODS: The patients who received PLI were assessed and divided into 2 groups. There were 38 patients (41 eyes) with a history or ocular findings of acute angle-closure attack in Group A, and 54 patients (70 eyes) who underwent prophylactic PLI in Group B. IOP over 18 mm Hg was considered to be re-elevated. The number of patients with re-elevated IOP and the duration until the re-elevation was investigated. RESULTS: The amount of IOP elevation immediately after PLI at 6, 24, and 48 months was 0.9, 2.5, and 2.6 mm Hg in Group A, and 0.1, 0.5, 0.5 mm Hg in Group B, respectively. The IOP re-elevation rate was 26.8, 40.0, and 51.4% at 6, 24, and 48 months in Group A and 8.6, 27.2, and 30.4% in Group B with statistically significant difference (p = 0.02, log-rank test). CONCLUSIONS: Close, long-term observation for patients who receive PLI is recommended because there is a high risk of IOP re-elevation within 1 year after PLI. After prophylactic PLI, IOP was maintained under 18 mm Hg for a longer period than after acute angle-closure attack, thus performing preventive PLI should be considered.