Rectangular Versus Triangular Scleral Flaps in Sub-Scleral Trabeculectomy

Trabeculectomy is the standard surgical procedure for management of uncontrolled open angle glaucoma. Several technical modifications for trabeculectomy were applied to improve the outcome and to increase its safety. To evaluate and compare the outcomes of the triangular versus the rectangular shaped scleral flaps in the surgery of sub scleral trabeculectomy in terms of intraocular pressure control, anterior chamber depth, postoperative astigmatism and complications. This study is a prospective comparative interventional and non-randomized study. It was carried out between February 2022 and September 2022. It was conducted on 20 eyes of 18 patients with uncontrolled POAG who were prepared for surgical treatment in the form of sub scleral trabeculectomy at Al-Zahraa University Hospital. Patients were divided into two equal groups: Group A: (10 eyes of 9 patients) were subjected to trabeculectomy with a rectangular scleral flap. Group B: (10 eyes of 9 patients) were subjected to trabeculectomy with a triangular scleral flap. Age + SD in group A was 55.5 ± 9.1 years, while in group B it was 53.3 ± 11.7 years with a statistically non-significant difference between both groups. There were statistically non-significant differences between both groups as regards the changes in IOP and astigmatism. Also, there were statistically non-significant differences between both groups as regards postoperative complications. There was hypotony in 8 patients (80%) of group A, versus 7 patients (70%) in group B which resolved on its own within a week by using frequent steroid. There was tight scleral suture in 1 patient (10%) in group A, and was not reported in group B. There was shallow AC in 3 patients (30%) in group A, versus 5 patients (50%) in group B which resolved on its own within a week. Over-filtration was not reported in group A, while it was reported in group B in 2 patients (20%) which resolved on its own within a week by using tight bandage. Both triangular and rectangular scleral flaps in trabeculectomy are safe and effective as regards post-surgical IOP control, bleb characteristics and complications.