The effect of argon laser trabeculoplasty on the medical control of primary open-angle glaucoma.

Argon laser trabeculoplasty was performed in 33 eyes with primary open-angle glaucoma whose intraocular pressures were poorly controlled on medical therapy. Five eyes (three patients) were failures and underwent trabeculectomy within three months. The remaining 28 eyes were followed up for 18 months and received a complete examination at periodic intervals. Beginning three months after trabeculoplasty, an attempt was made to decrease medications in a prospective manner in order to determine the least treatment required to maintain a pressure of less than 22 mmHg. No medication could be discontinued in 39% of eyes, whereas 18% were "cured" by trabeculoplasty and required no further medical therapy for control. Nine of 14 eyes that had been treated with carbonic anhydrase inhibitors were controlled without these drugs after trabeculoplasty. In 57% of eyes, the miotic could be discontinued. A total of 82% of cases still required some medication for pressure control after laser trabeculoplasty.