We compared the surgical successes of limbus- and fornix- based trabeculectomies in open- angle glaucoma ( OAG) eyes that had prior ocular surgery in the Collaborative Bleb- Related Infection Incidence and Treatment Study ( CBIITS), Japan. From the 1,098 glaucoma eyes in 34 clinical centers in CBIITS, 195 OAG eyes that had undergone previous trabeculectomy and/ or lens extraction were included. Limbus- or fornix- based trabeculectomy with mitomycin C were performed. Surgical failure ( IOP $ 21, 18, or 15 mmHg for criterion A, B or C, respectively;,20% decrease from baseline; reoperation for glaucoma; or loss of light perception vision) was counted. There were 106 and 89 eyes treated with limbus- and fornix- based trabeculectomies, respectively. At 3 years, IOP ( mean 6 SD) was 12.5 6 5.9 and 14.1 6 6.4 mmHg and the cumulative probabilities of failure during 3 years were 30.2% and 50.5% for criterion A, 40.3% and 57.4% for criterion B, and 57.9% and 65.8% for criterion C in the limbus- and the fornix- based group, respectively. Fornix- based incisions were associated with surgical failure in Cox- proportional multivariable analysis for criterion A [ relative risk ( RR) 5 1.96], and B [ RR 5 1.60]. Limbus- based trabeculectomy had a higher probability of success in OAG eyes with prior ocular surgery.
