Surgical Outcomes of Trabeculectomy Alone versus Trabeculectomy with Manual Small Incision Cataract Surgery Following Acute Angle Closure Glaucoma: A Comparative Study

Acute Angle Closure Glaucoma (AACG) is an ophthalmic emergency and is managed medically. Therapeutic options for the management of the post congestive phase are varied and no procedure has a documented therapeutic superiority over the other. Two established procedures were therefore chosen and compared to determine their therapeutic efficacy. Aim: To compare the surgical results of combined manual Small Incision Cataract Surgery (SICS) and trabeculectomy with standalone trabeculectomy in patients following an attack of AACG, with a final aim to decide which would be the better therapeutic approach in such a situation. Materials and Methods: This was a prospective observational study done in Bankura Sammilani Medical College located in West Bengal, India. Sixteen patients presenting with AACG in a 19 months study period from October 2019-April 2021 and having 50% or more synechial angle closure on indentation gonioscopy were selected for this study after obtaining necessary ethical clearance. Eight of them underwent trabeculectomy alone (Group A) and the rest underwent a combined procedure of trabeculectomy and SICS (Group B). They were followed-up for a six-months period and compared on the basis of Intraocular Pressure (IOP) control, Anterior Chamber (AC) depth and the requirement for further surgery. Results: Mean IOP following surgery at the end of six weeks in Group A was 15.98±1.56 mmHg whereas in Group B it was 12.01±1.18 mmHg. Results were compared by unpaired t-test, and the difference was statistically significant (p<0.001). Three out of eight patients (37%) in Group A developed cataract which caused a reduction in visual acuity and needed cataract surgery within the six months follow-up period but none of the patients in Group B needed any additional surgery. One patient in Group A needed additional medications due to uncontrolled IOP after surgery but no such event was noted in Group B. Seventy five percent patients in Group A had Grade 2 angles whereas 87% patients in Group B had Grade 4 angles as estimated by Van Herrick’s method. Conclusion: Combined trabeculectomy and SICS offers a better level of postoperative IOP control than trabeculectomy alone, and perhaps offers a better therapeutic option following AACG. Also, the chances of postoperative cataract formation and associated visual debility are eliminated.