Prevalence, Diagnostic Features, and Response to Trabeculectomy in Exfoliation Glaucoma

Abstract

The "true" prevalence and clinical attributes of exfoliation glaucoma remain controversial. The authors studied these characteristics in glaucoma patients requiring trabeculectomy. One hundred consecutive patients undergoing trabeculectomy for open-angle glaucoma were investigated by clinical examination (biomicroscopy and gonioscopy) and classified into three categories: exfoliation glaucoma, possible exfoliation glaucoma, and primary open-angle glaucoma (POAG). A definitive diagnosis of exfoliation glaucoma was provided by pathologic examination of iris tissue. All 22 patients with clinical evidence of exfoliation glaucoma and 4 of 18 patients with possible exfoliation glaucoma on clinical examination had ultrastructural evidence of exfoliation material. The prevalence of exfoliation glaucoma, therefore, was 26%. The clinical examination for the diagnosis of exfoliation glaucoma had an 85% sensitivity rate and a 100% specificity rate. In comparison with POAG, patients with exfoliation glaucoma had higher untreated intraocular pressure (IOP), higher IOP with medical therapy, and shorter duration of medical therapy. They were more often operated on for unacceptably high IOP. Exfoliation glaucoma patients exhibited significantly lower IOP after surgery. Exfoliation glaucoma is common in patients requiring trabeculectomy for open-angle glaucoma. This condition differs from POAG by a poorer response to medical therapy and a better response to trabeculectomy.