Evaluation of laser iridectomy in angle-closure glaucoma: provocative tests.

An argon laser iridectomy was performed on 18 eyes of 14 patients with closed-angle glaucoma. The intraocular pressure (IOP) was controlled in all but one eye within normal limits. Variable amounts of pigment were found on gonioscopy in all cases. The mydriasis test was positive in one eye (5.5%) after homatropine and in 5 eyes (28%) after tropicamide drops. 80% of the positive results occurred in lightly pigmented irides. The dark-prone position test was positive in 7 eyes (38%), 71% of the positive results occurring in heavily pigmented irides. Tomography was also performed; the possibility of trabecular damage is discussed.