Evaluation Of Peripapillary Nerve Fiber Layer Thickness And Macular Perfusion After Subscleral Trabeculectomy With And Without Mitomycin By OCT And OCT Angiography

Abstract

Objectives: Evaluation of peripapillary nerve fiber layer thickness and macular perfusion after sub-scleral trabeculectomy with and without mitomycin by OCT and OCT angiography. Subjects and Methods: An interventional study conducted from May 2020 to end of December 2021 in the ophthalmology department at Beni-Suef University Hospital, on ninety-nine patients with glaucoma, participants were within three groups: (33 patients underwent sub-scleral trabeculectomy without use of antimetabolite, 33 patients underwent sub-scleral trabeculectomy with use of sub-scleral Mitomycin 0.02% and 33 patients underwent sub-scleral trabeculectomy with use of subconjunctival Mitomycin 0.02%) to assess peripapillary nerve fiber layer thickness and macular perfusion after sub-scleral trabeculectomy with and without mitomycin by OCT and OCT angiography. Results: The three techniques were effective in lowering IOP significantly, compared with preoperative levels, there was a statistically significant difference between the trabeculectomy alone and trabeculectomy + MMC groups, regarding the degree of decrease in IOP that was significantly lowest among trabeculectomy alone group (p-value =0.031, 0.042), there was non-statistically significant difference between group (B) and group (C) (sub-scleral or sub-conjunctival MMC), with regard to the mean decrease in IOP. Superior and Inferior RNFL were slightly decreased in all studied groups in post- as compared with pre-operative assessment; however, this reduction was of non-statistically significant difference. The superficial and deep macular vessel densities were significantly increased in some (not all sectors), in pre- and post-assessment in the three studied groups, however the improvement in VD (%) was more among groups (B) and (C) as compared with group (A), (p-values <0.05).  Conclusions: Measurable changes occur in Vessel Density (%) but not in RNFL thickness after trabeculectomy as conducted by the three techniques (trabeculectomy, trabeculectomy + sub-scleral MMC and trabeculectomy+ sub-conjunctival MMC).