Comparison of 3 different anesthetic approaches for intravitreal injections: a prospective randomized trial
Purpose: To compare the anesthetic effectiveness of topical proparacaine drops, subconjunctival lidocaine, and 2% lidocaine gel. Methods: Ninety-two patients undergoing intravitreal injections were randomized to 1 of 3 groups: proparacaine 0.5% drops (Group Drops), proparacaine 0.5% drops plus subconjunctival lidocaine (Group SC), or 2% lidocaine gel (Group Gel). Patients were asked to score their pain experience using a visual analog scale of 0 to 10 immediately following the injections and 10 min, 1 h, 6 h, and 24 h after the injections. Patients also graded the overall injection experience as Excellent, Very Good, Fair, Poor, or Awful. The physician evaluated the patients’ eye movement during intravitreal injection on 3 levels: (0) none or minimal, (1) not compromising the injection, and (2) compromising the injection. Results: The patients in Group Drops had the worst mean pain scores during the injection and 10 min after, with the highest occurrence of movements compromising the procedure (Grade 2; 38.7%). The patients in Group SC had a higher percentage of good experiences (37.9%) but a higher incidence of chemosis (16.7%). The patients in Group Gel had similar overall pain scores to Group Drops patients but a higher incidence of keratitis (19.4%). There was no statistically significant correlation between the use of aspirin or anticoagulants and the occurrence of hyperemia or hyposphagma. Conclusion: Subconjunctival lidocaine was most effective in preventing pain and eye movements during intravitreal injections. Although 2% lidocaine gel produced a good overall experience for the patients, the incidence of keratitis was very high (19.4%). Therefore, we do not recommend 2% lidocaine gel as the first anesthetic choice for intravitreal injections. There is no evidence to suspend the use of aspirin or other anticoagulants drugs prior to intravitreal injections.