Combined Viscocanalostomy-Trabeculectomy for management of Advanced Glaucoma – A Comparative Study of the Contralateral Eye: A Pilot Study

PURPOSE To compare combined viscocanalostomy-trabeculectomy (VISCO-TRAB) to trabeculectomy (TRAB) for the management of advanced glaucoma. MATERIALS AND METHODS The study cohort comprised of 18 subjects with bilateral advanced glaucoma who underwent VISCO-TRAB surgery (VISCO-TRAB group) in the right eye and TRAB (TRAB group) in the left eye. VISCO-TRAB constituted lamellar scleral flap, deep scleral flap dissection with deroofing of Schlemm's canal (SC), viscodilation of SC, penetrating trabeculectomy, peripheral iridectomy, and tight flap closure. All eyes received subconjunctival mitomycin. Success criteria included intraocular pressure (IOP) < 14 mmHg or > 30% lowering of IOP with no devastating complications. A P value less than 0.05 was considered statistically significant. RESULTS Mean IOP was significantly lower after VISCO-TRAB compared to TRAB at 1 week and 3 months postoperatively (P<0.05). No eyes lost more than two lines of Snellen acuity. There were more hypotony-related complications after TRAB than VISCO-TRAB surgery. Target IOP was achieved in 83.3% in the VISCO-TRAB group compared to 55.6% in the TRAB group. CONCLUSION Combined VISCO-TRAB is effective in reducing IOP to the target level for advanced glaucoma with lower postoperative complications.