Comparisons of the short-term effectiveness and safety of surgical treatment for neovascular glaucoma: a systematic review and network meta-analysis

Author: Lin P, Zhao Q, He J, Fan W, He W, Lai M.

Geographical coverage: Not reported

Sector: Neovascular glaucoma

Sub-sector: Treatment

Equity focus: Not reported

Study population: Patients with glaucoma

Review type: Effectiveness review

Quantitative synthesis method: Network meta-analysis

Qualitative synthesis method: Not applicable

Background

Neovascular glaucoma (NVG) is a severe form of glaucoma caused by neovascularisation in the iris or anterior chamber angle. It is characterised by elevated intraocular pressure (IOP), pain, and vision loss. NVG treatment involves addressing the underlying cause, such as using intravitreal vascular endothelial growth factor (VEGF) inhibitors. When medical therapy proves insufficient, surgical interventions—such as glaucoma drainage devices (GDDs) and filtering surgeries—are commonly employed. While several studies have evaluated the effectiveness of these treatments, no clear consensus has been reached regarding the optimal approach.

Objectives

To compare the effectiveness and safety of six different surgical interventions for neovascular glaucoma.

Main findings

Overall, among six widely used treatment modalities for neovascular glaucoma, the Ahmed glaucoma valve combined with intravitreal anti-vascular endothelial growth factor (AGV+IVAV) and cyclophotocoagulation (CPC) were more effective in reducing IOP and improving success rates compared to the other four interventions.

A total of 9,658 articles were screened, and 23 studies involving 1,303 participants were included in the review. Of these, 19 were cohort studies and 4 were randomised controlled trials (RCTs). Six surgical techniques were evaluated across these studies.

The network meta-analysis indicated that, compared to AGV implant alone, both AGV+IVAV (MD = 4.74, 95% CI: 1.04 to 8.45) and trabeculectomy with mitomycin plus IVAV [Trab(MMC)+IVAV] (MD = 6.19, 95% CI: 0.99 to 11.40) resulted in more favourable IOP reduction six months post-surgery.

In comparison with cyclocryotherapy (CCT), the following treatments had significantly better success rates: AGV (OR = −0.17, 95% CI: −0.53 to −0.05), AGV+IVAV (OR = −0.10, 95% CI: −3.48 to −1.19), CPC (OR = −0.12, 95% CI: −0.53 to −0.05), Trab(MMC) (OR = 3.54, 95% CI: 1.15 to 10.91), and Trab(MMC)+IVAV (OR = 5.78, 95% CI: 2.29 to 14.61).

Efficacy rankings based on surface under the cumulative ranking curve (SUCRA) were as follows: Trab(MMC)+IVAV for IOP reduction at 6 months (SUCRA = 88.1), CPC at 12 months (SUCRA = 81.9), AGV+IVAV at 12 months (SUCRA = 79.9), and AGV+IVAV for success rate (SUCRA = 92.7).

Methodology

The literature search was conducted in PubMed, Embase, Web of Science, and the Cochrane Library. Eligible studies included RCTs and cohort studies reporting outcomes for NVG patients receiving surgical treatment, specifically evaluating intraocular pressure reduction (IOPR) or surgical success rates. Studies with fewer than 10 participants or less than six months of follow-up were excluded. Conference abstracts and comparative studies of similar procedures were also excluded.

Two reviewers independently screened studies and resolved disagreements with a third reviewer. Data extraction and quality assessment were also performed independently. Cohort studies were assessed using the Newcastle–Ottawa Scale, and RCTs were evaluated with the Cochrane risk of bias tool.

A network meta-analysis was conducted. Mean differences (MD) with 95% credible intervals were used for continuous outcomes, and odds ratios (OR) for dichotomous outcomes. Inconsistencies were checked using node-splitting and loop-specific methods. GRADE criteria were used to assess certainty of evidence. Funnel plot analysis was performed to evaluate publication bias.

Applicability / External validity

The review highlighted that the use of varied success criteria across studies poses challenges to the validity of pooled findings. Future research should prioritise high-quality randomised trials with standardised outcome definitions to support firmer conclusions.

Geographic focus

Studies were conducted in various regions, although specific locations were not detailed.

Summary of quality assessment

There is medium confidence in the conclusions of this review. While a comprehensive search strategy was used, the authors did not report checking reference lists and did not provide a full analysis of potential bias.