Comparison of Subconjunctival Injection vs. Sponge Application of Mitomycin C in Two-Site Phacotrabeculectomy: A Randomized Controlled Trial (Code-T0066)

Background: Phacotrabeculectomy, a combined procedure for cataract and glaucoma surgery, often requires the use of Mitomycin C (MMC) to enhance the success of filtration surgery by preventing scarring of the trabeculectomy site. MMC is traditionally administered through subconjunctival injection or sponge application, both of which aim to inhibit fibrosis and improve surgical outcomes. However, the efficacy and safety of these two methods remain a subject of debate.

Aims and objectives:

Primary

To compare the IOP control and complications of subconjunctival Mitomycin-C injection vs sponge application of Mitomycin-C in two-site phacotrabeculectomy surgery

Secondary

To compare the bleb morphology clinically (MBGS classification) and by imaging (ASOCT) between the two techniques of phacotrabeculectomy surgery.

Methods: This randomized controlled trial included 100 patients undergoing two-site phacotrabeculectomy for cataract and glaucoma management. Patients were randomly assigned to receive either subconjunctival injection (Group A) or sponge application (Group B) of Mitomycin C during the procedure. Primary outcomes included IOP reduction, the need for additional medications, and the occurrence of postoperative complications, such as hypotony, infection, or bleb leaks. Follow-up assessments were conducted at 1 week, 1 month, and 6 months post-surgery.

Results: Both groups demonstrated significant reductions in IOP post-surgery, with no significant difference in overall IOP control between the two groups. However, the sponge application group had a higher incidence of postoperative complications, including bleb leaks and hypotony (p < 0.05), while the subconjunctival injection group showed fewer complications and better bleb formation. The success rate was higher in the subconjunctival injection group at 6 months.

Conclusion: Subconjunctival injection of Mitomycin C in two-site phacotrabeculectomy appears to be more effective in terms of postoperative complication rates and bleb formation compared to sponge application. Both methods are effective in controlling IOP, but the injection method may offer a safer and more reliable approach.

Keywords: Phacotrabeculectomy, Mitomycin C, Subconjunctival Injection, Sponge Application, Glaucoma Surgery, Cataract Surgery.