Success and complication rates of trabeculectomies augmented with MMC in the management of glaucoma

Abstract

Glaucoma unresponsive to medical treatment is managed by surgery. Augmentation with mitomycin C (MMC) is considered in patients at high risk of surgery failure. Aim: In this paper we assess and compare the success and complications of this procedure performed in the local state hospital with those of larger international centres. Methods: A retrospective study of the surgery performed between 2003 and 2007 at St. Luke's Hospital by one surgeon (FM) was conducted. The total number of eyes considered in this analysis was 32. Intraocular pressures and complications up to one year post-operatively were recorded. Results: The mean intraocular pressure decreased from 30mmHg pre-operatively to 18mmHg post-operatively. The mean IOP drop registered was 42%. Of the 32 eyes that underwent trabeculectomy augmented by MMC, 23 were classified as a complete success with IOP remaining below 21mmHg at 1 year post-surgery. Six eyes were considered as a partial success since they had an IOP under 21mmHg but this had to be kept under control with the administration of medications. Failure of surgery was classified as uncontrollable UOP, although also on medications. This was seen in 3 eyes. Using the central limit theorem, the significance of the difference in means and difference in percentages of IOP drop and complication rates, between the local state hospital procedures and international centres were calculated. Conclusions: Incidences obtained from this analysis compare very favourably with results from international studies showing no significant differences.