Ahmed glaucoma valve implantation for secondary glaucoma post-vitrectomy

Int Ophthalmol. 2021 Oct 5. doi: 10.1007/s10792-021-02050-2. Online ahead of print.


Background and objective: Ahmed glaucoma valv (AGV) implantation is one of the successful surgical methods in secondary glaucoma that develops after pars plana vitrectomy (PPV). In our study, we aimed to evaluate the 1-year results of AGV implantation in patients with a history of PPV.

Study design: A total of 26 patients who underwent AGV implantation after PPV were included in our retrospective study. Fourteen of 26 patients had AGV implantation due to neovascular glaucoma (NVG) and 12 of them had secondary refractory galucoma. Data of these two groups of patients were evaluated in terms of IOP reduction, number of medication use, surgical complete and qualified success, surgical failure, and complications.

Results: The mean IOP was 29.54 ± 4.87 mmHg at the preoperative of AGV implantation and 12.88 ± 4.17 at the twelfth month visit in overal group. There was no statistically significant difference between two groups in terms of IOP in preoperative and all postoperative visits (p > 0.05). The mean intervals between PPV and AGV implantation were 67 ± 34 days in NVG and 391 ± 500 days in non-NVG group (p = 0.017). In overall group, 91.7% of patients had improvement in BCVA at the twelfth month visit. Complete and qualified surgical success rates were 75%, 83.3% in NVG group and 50%, 91.7% in non-NVG group, respectively. There was no devastating complication in both groups.

Conclusion: AGV implantation is a safe and effective surgical method in uncontrolled IOP elevations after PPV. While surgical success and failure rates were similar between etiologies, the time required for AGV implantation after PPV was shorter in NVG etiology.

Keywords: Ahmed glaucoma valv; Neovascular glaucoma; Pars plana vitrectomy; Secondary glaucoma.