Tunneled scleral incision to prevent vitreal reflux after intravitreal injection

Purpose: To investigate the efficacy of tunneled scleral incision compared with standard straight scleral incision to prevent vitreal reflux after intravitreal (IVT) injection. Design: Prospective comparative controlled nonrandomized clinical study. Methods: Eighty-eight eyes undergoing IVT-injection were allocated into four groups to compare the vitreal reflux after injection of 0.1 ml of triamcinolone acetonide (TA) and Avastin using a tunneled vs straight injection technique. The amount of intraoperative drug reflux was estimated by measuring the width of the subconjunctival bleb. Results: The mean measured reflux of volume was statistically less with the tunneled scleral incision (1.13 mm standard deviation [SD] +/- 1.16 for TA; 1.13 mm SD +/- 1.39 for Avastin) than in eyes undergoing the straight scleral injection (3.00 mm SD +/- 1.77 for TA; 3.18 mm SD +/- 1.68 for Avastin) for both Avastin and TA IVT-injections groups (P < .001). Conclusions: The tunneled scleral incision promotes statistically significant less vitreal reflux for IVT drug injection.