EFFECT OF ANESTHESIA DURATION ON INTRAVITREAL INJECTION PAIN A double-blinded, randomized, comparative study

Purpose:To determine the effect of different durations of topical anesthesia on intravitreal injection (IVI) pain.Methods:This was a double-blinded, randomized, comparative study. Three hundred and twelve sequential eyes undergoing IVI were randomized to one of six groups according to the duration of topical anesthesia (from 1 to 30 minutes, one group for every 5-minute range, Groups 1-6). Topical anesthesia before IVI was standardized. Patients graded their pain using the visual analog scale and the Wong-Baker FACES scale at 15 minutes after the procedure.Results:The pain scores among the six groups were significantly different for the visual analog scale (P = 0.013) and Wong-Baker FACES scale (P = 0.024). The mean pain scores for Group 4 were 1.97 & PLUSMN; 1.04 (visual analog scale) and 2.02 & PLUSMN; 1.08 (Wong-Baker FACES scale) and were significantly lower than those of Group 1, 2, 5, or 6.Conclusion:The duration of topical anesthesia significantly correlated with IVI pain. Preoperative 0.5% proparacaine hydrochloride drops were most effective in relieving IVI pain 11 to 20 minutes after topical administration.