Randomized clinical trial evaluating reflux, IOP, and pain, following intravitreal anti vascular endothelial growth factors injections using 30g and 32g needles

Purpose : To assess the differences in reflux, IOP and pain scores, between intravitreal injections (IVI) performed with 30g and 32g needles. Methods : A prospective, randomized interventional study of patients who required bilatetal intravitreal anti‐VEGF injection (n=61). One eye was randomized to receive a 30g needle and the contralateral eye to 32 g. Immediate postinjection reflux, our primary outcome, was noted at he time of injection and recorded as a binary outcome (yes or no); pain was quantifled using a VAS pain scale and IOP pressure was measure before and 5 minutes after IVI. Our study was designed to detect a 10% difference in the proportion of patients with reflux, assuming an alpha of 0.05 and power of 80%. Results : Postinjection reflux was present 40% in 30G and 24% in those who recieved injection with a 32G needle (x2=4.5; p‐value = 0.033). A trend was noted whereby eyes randomized to 32 g needle had less pain (31% reported no pain as compared to 23% in the 30 g Group). A trend was noted for a higher IOP with a 31% elevation in the 32 g Group, as compared to 25% in the 30 g Group. On average, patients preferred the 32 g needle. Conclusions : In this study, 32 g Needles are associated with less postinjection reflux, a trend toward less pain, but a trend towards a transient increase in IOP. A patient preference for 32 g Needles was noted.