A One-Year Prospective Study To Evaluate The Efficacy Of Intraoperative Subtenon Injection Of 0.01 % Mitomycin-C As An Adjunct To Trabeculectomy In Patients Admitted To Shri Bm Patil Medical College And Research Centre, Vijayapura

Abstract

Background: Glaucoma, characterised by optic neuropathy and elevated intraocular pressure (IOP), is a leading cause of global blindness, affecting 3.54% of individuals aged 40 to 80. Trabeculectomy, enhanced with antimetabolites like Mitomycin C (MMC), has long been the gold standard filtering surgery for glaucoma. The conventional method of MMC application involves using soaked sponges over the subconjunctival space. However, this approach can result in complications such as blebitis and foreign-body granuloma due to residual sponges. Recent research has explored intraoperative MMC injection to improve outcomes and reduce complications. This study aims to assess the safety and efficacy of a low dose (0.1 mg/ml) of MMC administered through subtenon injection during trabeculectomy, with a follow-up period of over 6 months.

Materials and Methods: It is a prospective interventional study on patients who underwent trabeculectomy with a subtenon injection of 0.1mg/ml of Mitomycin C combined with Small incision cataract surgery with intraocular lens implantation and were followed up over 6 months. Efficacy was determined in terms of intraocular pressure reduction, bleb architecture was graded using the Indiana Bleb Appearance Grading System (IBAGS), and safety was commented upon regarding postoperative complications.

Results: Thirty patients were enrolled, with the majority having primary open-angle glaucoma (63.33%), while 36.67% had primary angle-closure glaucoma. Baseline intraocular pressure (IOP) was 31.40 (± 10.38) mmHg. It significantly reduced to 14.60 (± 3.75) mmHg on the first postoperative day, decreasing to 9.55 (± 1.57) mmHg by the 6th postoperative month (p = 0.001). The percentage reduction in IOP was substantial, 69.57%, by the 6th postoperative visit. Bleb morphology assessment using IBAGS revealed significant improvements in bleb height, extent, and vascularity over the 6-month follow-up (p = 0.001). Out of the total patients,93.33% achieved controlled IOP without antiglaucoma medications, while 6.67% required one medication for IOP control. Complications were minimal, with transient corneal oedema in six patients and manageable postoperative hypotony in one case.

Conclusion: A sub-tenon injection of MMC effectively reduces intraocular pressure and promotes favourable bleb architecture, offering a safe and minimally complicated alternative to the conventional approach. It can be safely considered in high-risk patients as an alternate route of MMC application during trabeculectomy.