AIM: To evaluate the safety and efficacy of Ahmed glaucoma valve implantation for refractory glaucoma after sequential failed trabeculectomy.

METHODS: Thirty-six patients(36 eyes)with prior failed sequential trabeculectomy who underwent Ahmed glaucoma valve implantation were included. The intraocular pressure(IOP), best corrected visual acuity(BCVA)and complications were ovserved and all the patients were followed up at least for 12mo.

RESULTS: Mean preoperative IOP was 35.20±7.28mmHg and reduced to 10.15±3.34, 11.23±3.56, 15.63±5.72, 17.17±5.47, 17.73±6.23,19.76±5.43mmHg at 1, 2wk, 1, 3, 6 and 12mo after surgery, which was significant different from the preoperative level(t=12.643, 11.837, 10.324, 8.839, 8.462, 8.046, all P<0.05). Visual acuity was not significantly different between pre-operation and 12mo post-operation(Z=-0.420, P>0.05). At 12mo after operation, the complete success rate reached 78% and the conditional success rate reached 92%. There were 5 eyes complicated with shallow anterior chamber, 3 eye complicated with anterior chamber hemorrhage, which all recovered after additional treatments. Late complications included valve exposure and encapsulated cystic blebs around the plate. Severe corneal endothelium loss occurred in 1 patient.

CONCLUSION: Ahmed glaucoma valve implantation is effective in reducing IOP at 1-year follow-up in refractory glaucoma patients with prior sequential failed trabeculectomy, but we should fully understand and attach great importance to all kinds of complications that may occur.