ADVERSE-EFFECTS OF TOPICAL ANTIGLAUCOMA MEDICATION .2. THE OUTCOME OFFILTRATION SURGERY

Objective: To determine the effect of long-term topical antiglaucoma t herapy on the results of glaucoma filtration surgery and to relate any differences to the cell population profile of the conjunctiva. Method s: Filtration surgery was performed in 124 patients (trabeculectomy in 112 and triple procedures [trabeculectomy, cataract extraction, and i ntraocular lens implantation] in 12), and the outcome of these procedu res was assessed after a minimum follow-up of 6 months. A conjunctival biopsy specimen was obtained at the time of surgery. The patients wer e divided into four groups according to the type of topical therapy ad ministered. The duration of therapy tended to be greater for the patie nts treated with a greater number of medication types. The outcome of trabeculectomy was assessed in 106 of the patients. Results: In compar ison with the briefly treated-primary surgery group, the success rate of trabeculectomy (90% [n=28]) was similar to that in the group treate d with beta-blockers (93% [n=29]). The trabeculectomy success rate for patients treated with beta-blockers and miotics was significantly low er (72%, P<.01 [n=29]), and that for the group treated with beta-block ers, miotics, and sympathomimetics was even lower (45%, P<.001, [n=20] ). Conclusions: Various treatment regimens were associated with differ ential effects on the success rate of trabeculectomy. Long-term topica l combination therapy was identified as a significant risk factor for failure of trabeculectomy. Preoperative conjunctival cell counts from patients whose trabeculectomies were successful were compared with tho se whose trabeculectomies failed. Failure was associated with signific antly more pale cells (P<.01), macrophages (P<.05), and lymphocytes (P <.05) in the epithelium; fibroblasts (P<.05) and macrophages (P<.05) i n the superficial substantia propria; and both macrophages and lymphoc ytes in the deep substantia propria (P<.01). Thus, preoperative subcli nical conjunctival inflammation induced by previous topical medication was identified as a risk factor for failure of trabeculectomy.