Ahmed Glaucoma Valve Implantation: Graft-Free Short Tunnel Small Flap versus Scleral Patch Graft after 1-Year Follow-up: A Randomized Clinical Trial

Purpose: To compare the efficacy and safety of the graft-free short tunnel small flap (STSF) technique with that of the scleral patch graft (SPG) in Ahmed glaucoma valve (AGV) (New World Medical Inc, Rancho Cucamonga, CA) implantation. Design: Randomized clinical trial. Participants: A total of 203 eyes of 203 patients with medically uncontrolled glaucoma, including 102 in the STSF group and 101 in the SPG group. Methods: Patients were enrolled and assigned randomly to STSF or SPG. Main Outcome Measures: Tube exposure, intraocular pressure (IOP), number of glaucoma medications, best-corrected visual acuity, surgical complications, and success rate (defined as IOP >5 mmHg, ≤21 mmHg, and IOP reduction ≥20% from baseline at 2 consecutive visits after 3 months, no reoperation for glaucoma). Results: Only 1 patient in the SPG group developed tube exposure at 1-year follow-up. The cumulative probability of success during the first year of follow-up was 70% in the STSF group and 65% in the SPG group (P = 0.36). The IOP decreased significantly from 29.6±8.6 mmHg at baseline to 16.4±3.6 mmHg at the final follow-up in the STSF group (P = 0.001). The corresponding numbers for the SPG group were 30.9±11.2 and 15.8±4.7, respectively (P = 0.001). The final IOP was comparable between both groups (P = 0.65). Mean ± standard deviation of the number of glaucoma medications was 1.8±0.9 in the STSF group and 1.6±0.9 in the SPG group at final follow-up (P = 0.32). Postoperative complications developed in 8 patients (19%) in the STSF group and 9 patients (23%) in the SPG group (P = 0.81). Conclusions: The STSF and SPG techniques had a comparable complication rate at the 1-year follow-up. Both techniques were comparable in terms of success rate, postoperative IOP, and glaucoma medications.