Risk of postoperative visual loss in advanced glaucoma.

The incidence of sudden visual loss after an intraocular procedure in patients with glaucoma and visual field defects has been disputed for over a century. We examined the risk of sudden visual loss associated with trabeculectomy in glaucoma patients with advanced visual field defects. Fifty-four filtering operations performed on 44 patients were reviewed. All patients had visual field defects encroaching on or splitting fixation, a visual acuity of 20/100 or better, and a follow-up period of at least two months. Thirty-one of the 54 preoperative visual fields (57%) disclosed a fixation-splitting defect. Sudden visual loss was not observed in any patient during the two-month postoperative period. These findings suggest that the incidence of sudden postoperative visual loss is lower than previously reported.