Superior subconjunctival anesthesia versus retrobulbar anesthesia for manual small-incision cataract surgery in a residency training program: a randomized controlled trial

PURPOSE To evaluate the effectiveness of subconjunctival anesthesia as compared to retrobulbar anesthesia for pain control during manual small-incision cataract surgery (MSICS) performed by third-year residents. DESIGN A randomized, controlled trial. PATIENTS AND METHODS A total of 150 patients undergoing routine cataract surgery were randomly assigned to receive either subconjunctival anesthesia (group 1, n = 75) or retrobulbar anesthesia (group 2, n = 75). Third-year residents performed MSICS using the modified Blumenthal technique. Subconjunctival anesthesia was administered by injecting 2% xylocaine with adrenalin into the superior conjunctiva, and retrobulbar anesthesia by injecting 2 mL of 2% xylocaine with adrenalin into the retrobulbar space. We studied the following variables: intraoperative pain score rated on a 100-point visual analog scale (VAS), operative time, and injection and operative complications. RESULTS A mean age of 69 vs 70 years, an operative time of 47.1 (SD, 9.9) min vs 47.7 (10.9) min, and a median (interquartile range) pain score of 40 (range, 20-70) vs 40 (range, 20-50) were observed in the subconjunctival and the retrobulbar groups, respectively. The injection complication of subconjunctival hemorrhage was significantly higher in the subconjunctival group (25.3%) compared to the retrobulbar group (1.3%). The operative complication rate between groups was not different (P > 0.05). CONCLUSION Both, superior subconjunctival anesthesia and retrobulbar anesthesia were effective during MSICS when used in a residency training program.