THE ROLE OF ADJUNCTIVE MITOMYCIN-C IN SECONDARY GLAUCOMA TRIPLE PROCEDURE AS COMPARED TO PRIMARY GLAUCOMA TRIPLE PROCEDURE

Objective: This study aimed to investigate whether previously failed g laucoma filtration surgery is a risk factor for filtration failure of subsequent trabeculectomy combined with cataract surgery and to determ ine the role of adjunctive mitomycin C (MMC) in the secondary glaucoma triple procedure (SGTP) as compared to primary glaucoma triple proced ure (PGTP). Design: A prospective, controlled study that was randomize d with respect to assignment to adjunctive MMC and a case-control desi gn with respect to comparisons between SGTP and PGTP was studied. Part icipants: The SGTP group consisted of 49 eyes of 49 consecutive patien ts with primary open-angle glaucoma with a history of glaucoma filtrat ion surgery requiring glaucoma medical therapy and in need of cataract surgery, randomized to adjunctive MMC (SGTP MMC subgroup of 21 eyes) and no adjunctive MMC (SGTP control subgroup of 28 eyes). The PGTP gro up consisted of 49 PGTP cases closely matched to the SGTP cases with r espect to age, race, gender, MMC use, C:D ratio, and systemic diseases . Intervention: Trabeculectomy combined with phacoemulsification and a small incision (5 x 6 mm), all polymethylmethacrylate posterior chamb er intraocular lens implantation with or without adjunctive MMC (0.5 m g/ml for 1 minute), was performed. Main Outcome Measures: Surgery fail ure was defined as the need of an additional intraocular procedure or the need of more than one medication to achieve intraocular pressure c ontrol to the target level. intragroup and intergroup comparisons were made with respect to filtration outcome among the SGTP and PGTP patie nts. Results: Without adjunctive MMC, filtration success was significa ntly less in SGTP than in PGTP (P = 0.03). Adjunctive MMC significantl y increased the success rate of SGTP (P = 0.02) but not that of PGTP ( P = 0.89) over the average follow-up period of 2 years. Conclusions: P reviously failed glaucoma filtration surgery is a significant risk fac tor for the filtration failure of combined surgery. Intraoperative use of adjunctive MMC significantly improves the filtration success rate of SGTP.