A systematic review and meta-analysis of randomised controlled trials in the management of neovascular glaucoma: absence of consensus and variability in practice

Abstract

Abstract Purpose Neovascular glaucoma (NVG) is characterised by neovascularisation of the angle and therefore elevated intraocular pressure (IOP). This results in progressive optic neuropathy and loss of visual acuity. Treatment aims to reduce IOP in order to prevent optic nerve damage. A systematic review was completed synthesising results from randomised control trials (RCTs) comparing interventions for the management of NVG and their efficacy and safety. Methods Data was sourced from Web of Science, Embase and Medline after 1st January 2000. The primary outcome measures were mean IOP at follow-up and success rate. The secondary outcomes included mean IOP lowering medications and total complications. A meta-analysis was completed on comparative studies using Revman (version 5.4). Results For the two studies comparing Ahmed glaucoma valve (AGV) + pan-retinal photocoagulation (PRP) vs AGV + PRP + intra-vitreal bevacizumab (IVB), there was no difference in mean IOP or odds of success from the meta-analysis. From the 4 studies examining the utilisation of anti-vascular endothelial growth factor (anti-VEGF), one study showed lower mean IOP at 1 (p = 0.002) and 3 months (p = 0.033) for IVB vs sham injection. In the 2 studies studying transcleral diode laser (TDL), there were no significant findings. From the 4 studies looking at trabeculectomy (trab), lower mean IOP at 6 (p = 0.001), 9 (p = 0.01), 12 (p = 0.02) and 18 months (p = 0.004) was shown for intra-vitreal ranibizumab (IVR) + PRP + visco-trabeculectomy vs IVR + PRP + trab, and a significantly lower mean IOP was present in the Baerveldt group vs trab at 6 months (p = 0.03). In the 2 studies investigating the AGV, there was a lower mean IOP at 1 month (p = 0.01) in the AGV + triamcinolone (TCA) group. The risk of bias was low for 4 studies, high for 4 studies and 6 studies had some concerns. Conclusion This is the first meta-analysis of RCTs in the management of neovascular glaucoma. The lack of high-quality evidence contributes to the lack of consensus in managing NVG. Our results highlight modern treatment strategies and the need for better powered RCTs with long-term follow-up in order to establish optimal treatment modalities and true patient outcomes.