Vision results after glaucoma surgery in dogs after valve failure

Abstract

OBJECTIVE: The aim of this study was to retrospectively evaluate vision outcomes of dogs with primary angle closure glaucoma (PACG) that underwent Ahmed valve gonioimplantation (AVG) followed by lensectomy and endolaser cyclophotocoagulation (ECP) with or without bleb resection after AVG failure. PROCEDURE: Medical records from 2008 to April 2022 were reviewed. All patients selected had an AVG performed first. Following valve failure, lensectomy-ECP was performed in addition to bleb resection as indicated. Additional ECP and AVG replacement surgeries were performed as deemed medically necessary. Main outcomes evaluated included vision preservation, average IOP reduction, and the number of glaucoma medications (both oral and topical) at 6, 12, 24, and 36 months. RESULTS: Fourteen eyes from 13 patients were included in the study. Females were predominant (n = 9) compared with males (n = 4). Mean age at initial glaucoma diagnosis was 6.82 years. Following AVG and lensectomy-ECP, vision was preserved in 93%, 84%, 60%, and 48% of eyes at 1, 2, 3, and 4 years respectively. Following lensectomy-ECP, there was a significant reduction in mean IOP of 9.64 mmHg (p = .015) and 9.71 mmHg (p = .016) at 2 and 6 months, respectively. There was a reduction in mean IOP of 2.45, 7.25, and 12.25 mmHg at 12, 24, and 36 months, respectively, which was not statistically significant. There was a significant decrease in the number of glaucoma medications at all evaluated time points except 24 months. CONCLUSIONS: Combined AVG and lensectomy-ECP is successful in maintaining vision long term as well as decreasing IOP, and the number of glaucoma medications administered.