Long-term follow-up of 700 trabeculectomies

Abstract

A major focus of our study was to determine the value of postoperative intraocular pressure (IOP) in predicting the outcome of trabeculectomy (TE). The medical charts of 547 patients undergoing glaucoma filtering surgery at the Department of Ophthalmology of the University of Cologne from 1987 to 1996 were reviewed. The eyes with congenital glaucoma and those treated with anti-metabolites were excluded. Defining the qualified criteria for success of trabeculectomy as an IOP </21 mm Hg throughout the entire study period, no evidence of progressive disc damage or further visual field loss, no decrease in visual acuity and no additionally required surgical intervention due to glaucoma, there was a success rate of 44.4%. In 50% the tonometric failure took place within the first 34 days trabeculectomy. No significant difference in survival by sex (p = 0.53), surgical technique, limbal versus fornix-based flap (p = 0.28) and by type of glaucoma (p = 0.26) was shown. But the patient group with prior argon laser trabeculoplasty had a significant lower success rate in terms of normalization of IOP (p = 0.03). There was no significant difference in the outcome of trabeculectomy between the first and second eye. The identification of patients at risk of failure in terms of IOP in the early post-operative period is possible, thus, closer follow-up and early medical or surgical intervention may be indicated. Should trabeculectomy be the therapy of first choice in the early stage of glaucoma and in case of failure in the first eye, this would allow options, such as the use of anti-metabolites in the second eye.