Effect of timolol on intraocular pressure elevation following argon laser iridotomy

Argon laser iridotomy was performed in 123 eyes of 83 patients with primary angle-closure glaucoma. Sixty-three eyes received argon laser iridotomies with timolol pretreatment and the other 60 eyes served as controls. There were 43 eyes (71.7%) in the control group and 32 eyes (50.7%) in the timolol-pretreated group, whose intraocular pressure increased significantly over baseline level 2 hours after laser treatment. There was statistical difference in the incidence of intraocular pressure elevation in these two groups. Seven eyes (11.7%) in the control group and 4 eyes (6.2%) in the timolol-pretreated group had intraocular pressure elevation at least 11 mmHg over baseline. Additional 28 patients, who received argon laser iridotomy bilaterally, one eye with timolol pretreatment and the other eye served as a matched control, revealed that eyes which were timolol pretreated had statistically significant less intraocular pressure elevation.