Trabeculectomy with releasable sutures in primary glaucoma: A comparative study with the conventional technique

Aim: To compare the short term and long term efficacy of using releasable sutures versus the conventional permanent sutures for scleral flap suturing in trabeculectomy in terms of incidence of short term hypotony and its related complications, short term shallowing of anterior chamber, long term IOP control after operations by both techniques and post-operative bleb scores. Materials and Methods: This is a prospective study carried out to compare the safety, efficacy and long term success rate of trabeculectomy with releasable suture verses trabeculectomy with permanent sutures. 60 eyes of primary uncontrolled glaucoma were subjected to trabeculectomy surgery, 30 using permanent sutures and 30 using releasable sutures. Patient were randomly assigned into 2 groups for conventional trabeculectomy with interrupted suture (group 1) and trabeculectomy with releasable suture (group 2). Patients were assessed postoperatively on visual acuity, intraocular pressure, anterior chamber depth, immediate complications, anterior chamber depth, post-operative lens changes. Results: Majority patients were male. Age occurrence of open angle glaucoma was between 51-60 years while angle closure glaucoma was between 40 to 50 years. None of the eyes had severe hyotony (IOP less than 6 mmHg in trabeculectomy with releasable suture, while hypotony was a major complication in trabeculectomy with permanent sutures group. Post-operative mean IOP from the end of 3 months till 12 months was found to be equivalent in both groups. In group 1, 5 eyes (16.66%) anterior chamber was well formed compared to 21 eye in group 2. Bleb scores in both the groups suggested, none of the patients in Group 1 had high bleb score between 2-5 days while 13 patients (43.33%) in group 2 had high bleb score. Visual field loss progressed in 5 eyes, 16.66% in group 1. While none of patients had progressive field loss in group 2. Gross hypotony in immediate post-operative period was observed in group 1 while none pts in group 2 showed post-operative hypotony. Conclusion: Suture release after trabeculectomy has been a useful adjunctive to conventional filtration surgery. It enables the filtration capacity to increase post operatively, decreasing the IOP without another invasive procedure or special instrumentation. It allows surgeon to achieve tighter closure of scleral flap with the assurance that filtration capacity can be increased as needed during post-operative period. Keywords: Glaucoma, Releasable sutures, Trabeculectomy.