Glaucoma surgery with soaked sponges with mitomycin c vs sub-tenon injection: Short-term outcomes

Aim: The aim of this study is to compare the outcomes, success rates, complications, and number of interventions of the trabeculectomy surgery with mitomycin C (MMC) in two different techniques: conventional soaked sponges and sub-Tenon injection. Materials and methods: An observational retrospective study was performed with 79 eyes of 64 participants who underwent a glaucoma surgery with MMC. The conventional sponge soaked with MMC 0.03% for 3 minutes over the scleral flap (group I) and the subtenon injection of 0.1 mL of MMC 0.03% (group II) techniques were used to deliver the MMC. The data collected were patient demographics, preoperative intraocular pressure (IOP), central corneal thickness (CCT), number of pre- and postoperative ocular hypotensive drugs, postoperative complications, number of interventions, and need of further glaucoma surgery. Results: Seventy-nine eyes were divided into two: 39 eyes (49.37%) in group I and 40 eyes (50.63%) in group II. Trabeculectomy was performed in 53.17% and phacotrabeculectomy in 46.83%. The IOP decreased from 18.0 ± 11.0 mm Hg at the baseline to 10.0 ± 3.0 mm Hg at the last visit in group I and, in group II, from 16.0 ± 10.0-13.0 ± 6.0 mm Hg (median ± ID), p < 0.001. There were no significant differences between the groups regarding demographics, median follow-up, IOP in baseline, CCT, drugs reduction, success criteria adopted, postsurgical interventions, surgical complications, and need for new procedures (p > 0.05). Conclusion: Sub-Tenon injection of MMC is a safe and as effective as the conventional soaked sponge method in trabeculectomies. This method reduces surgical time and sponge-related risks with equivalent surgical efficacy. Clinical significance: As trabeculectomy is still the most common surgical procedure to reduce IOP and scar formation is one of the main causes of surgical failure, it is important to develop surgical techniques to improve its outcomes.