Outcomes of Ahmed Glaucoma Valve Implantation with Subsequent Trans-Scleral Diode Cyclophotocoagulation as the Main Intervention if IOP Remained Medically Uncontrolled

Abstract

Purpose: To evaluate the efficacy and safety of Ahmed glaucoma valve (AGV) implantation with subsequent trans-scleral diode cyclophotocoagulation (CPC) as the main intervention if IOP remained medically uncontrolled.

Patients and methods: Charts of 108 consecutive eyes (90 patients) that underwent AGV implantation from 2003 to 2018 at a single clinical practice were retrospectively reviewed. The procedure was considered a failure if any of the following occurred: additional incisional glaucoma surgery, IOP >21 mmHg or < 20% reduction from baseline on 2 consecutive study visits after 3 months, IOP ≤ 5 mmHg on 2 consecutive study visits after 3 months, loss of light perception, or AGV removal.

Results: The mean follow-up time was 5.4 ± 3.1 years. Diode CPC was performed in 32%. The mean IOP was 24.8 ± 8.2 mmHg before intervention, and 12.5 ± 5.6 mmHg at last follow-up (p<0.0001). The mean logMAR VA decreased by 0.24 (p=0.002). The success rate was 68%. The reasons for failure were additional incisional glaucoma surgery in 7%, AGV removal in 4%, loss of light perception in 4%, inadequate IOP reduction in 13%, and IOP ≤ 5 mm HG in 6%. The probability of survival by Kaplan Meier analysis was 88%, 76% and 69% at 1, 3, and 5 years after the procedure, respectively. Complications of AGV and CPC were comparable to those previously reported in the literature.

Conclusion: The treatment approach of AGV implantation with subsequent trans-scleral diode CPC, as needed, was successful in over 2/3rd of subjects. This study adds to the literature supporting the use of CPC when IOP is medically uncontrolled after AGV.

Keywords: cyclodestruction; laser; surgery; valved glaucoma implant.

Figure 1

Intraocular pressure (IOP) after Ahmed Glaucoma Valve (AGV).

Figure 2

Kaplan Meier Curve showing survival probability after AGV. The procedure was considered a failure if any of the following criteria were met: additional IOP lowering incisional surgery (CPC was not considered a failure), IOP >21 mmHg or less than 20% reduction below baseline on 2 consecutive study visits after 3 months, IOP ≤ 5 mmHg on 2 consecutive study visits after 3 months, loss of light perception, or AGV removal.

Figure 3

Kaplan Meier Curve showing survival probability after AGV. The procedure was considered a failure if any of the following criteria were met: additional IOP lowering procedure (including CPC), IOP >21 mmHg or less than 20% reduction from baseline on 2 consecutive study visits after 3 months, IOP ≤ 5 mmHg on 2 consecutive study visits after 3 months, loss of light perception, or AGV removal.