[Laser trabeculoplasty in glaucoma chronicum simplex. Results of a prospective, clinical study]

Between 1984 and 1986, 104 patients with open-angle glaucoma of various etiologies were treated by laser trabeculoplasty (LTP) in a prospective clinical study. In order to ensure that the group of patients studied was homogeneous, only the 85 consecutive patients (85 eyes) with primary open-angle glaucoma were included, using a specially designed software program. The number of patients with pseudoexfoliation glaucoma, aphakic glaucoma, and congenital glaucoma was too small to allow statistical comparison with those who had chronic open-angle glaucoma. Criteria for success were defined as follows: no progression of disk cupping or visual field defects, mean intraocular pressure below 24 mm Hg as calculated by a day profile, and no increase in medication. These conditions were satisfied by 76% of the patients after six months and by 64% after 12 months. Initially, coagulations were performed over 180 degrees in the inferior circumference. If this did not suffice, the upper 180 degrees were also coagulated. If LTP is to be effective, thorough coagulation with tender blanching effects is mandatory. Average preoperative pressure values of over 22 mm Hg and a postoperative pressure increase of between 5 and 14 mm Hg are favorable prognostic signs. None of the parameters age, sex, duration, intensity of glaucomatous disease, or preoperative medication had any influence on the efficacy of LTP. In 14 of the 45 patients in whom only one eye was treated a simultaneous decrease in pressure was also observed in the untreated eye. The side effects of LTP bear no relation to its benefits, so that LTP is very suitable as a therapy between medication and surgery. Careful follow-ups of the patients are necessary because of possible increases in intraocular pressure in the course of time.