Effect of Needle Gauge Size on Pain During Intravitreal Anti-VEGF Injection: A Systematic Review and Network Meta-Analysis

Abstract

Abstract Introduction Concerns related to pain from intravitreal injections are one of the key factors mentioned by patients when asked about therapy. In this systematic review and network meta-analysis, we evaluate the literature of comparative clinical trials on the relationship between needle gauge size and pain experience during intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy. Methods We searched 12 literature databases on 14 October 2023 for comparative studies of gauge sizes for intravitreal anti-VEGF injections. The primary outcome of interest was the reported pain experience immediately after the injection. All outcomes of pain were transformed into standardized effect sizes using Cohen’s d. Using a network meta-analysis approach, we were able to compare all gauge sizes and rank them according to the reported pain experience. Results We identified nine eligible studies with data on a total of 998 patients and 1004 eyes. Needle sizes studied were 26-gauge, 27-gauge, 29-gauge, 30-gauge, 32-gauge, 33-gauge, and 34-gauge. A complete network was present, which allowed for a network meta-analysis. We used the thickest (26-gauge) needle as the reference group and observed a clear trend of lower pain experience with thinner gauge sizes (d: −0.4, d: −2.7, d: −3.8, d: −4.8, d: −4.5, and d: −5.3; respectively, for 27-gauge, 29-gauge, 30-gauge, 32-gauge, 33-gauge, and 34-gauge). Conclusion A gauge size of 30 or thinner may minimize patient discomfort related to intravitreal anti-VEGF therapy.

Keywords

• Intravitreal injection
• Anti-VEGF
• Pain
• Systematic review
• Network meta-analysis