A COMPARISON OF TOPICAL AND RETROBULBAR ANESTHESIA FOR CATARACT-SURGERY

Purpose: To evaluate and compare the efficacy of topical and retrobulb ar anesthesia for cataract extraction with intraocular lens implantati on. Methods: One hundred thirty-eight patients prospectively were assi gned to the topical (group 1; n = 69) or retrobulbar (group 2; n = 69) anesthesia groups by permuted block restricted randomization. Group 1 received topical 0.75% bupivacaine and intravenous midazolam and fent anyl for anesthesia. Group 2 received intravenous methohexital followe d by retrobulbar block with an equal mixture of 2% lidocaine and 0.75% bupivacaine plus hyaluronidase (150 U). A visual pain analogue scale was used to assess the degree of pain during the administration of ane sthesia, during surgery, and postoperatively. The degree to which eye movement, touch, and light caused patient discomfort was assessed. Com plications and surgical conditions were recorded. Results: There was n o difference in the surgical conditions (P = 0.5) or pain during surge ry (P = 0.35) between the two groups. There was more discomfort during administration of topical anesthesia (P < 0.0001) and postoperatively (P < 0.05) in the topical group. Chemosis, subconjunctival hemorrhage , and eyelid hemorrhage were seen almost exclusively in the retrobulba r group. One patient in group 2 had a retrobulbar hemorrhage. Although eyeball movement and squeezing of the eyelids were present more frequ ently in the topical group, neither was a problem to the surgeon. Conc lusion: Topical anesthesia can be used safely for cataract extraction. The degree of patient discomfort is only marginally higher during adm inistration of the anesthesia and postoperatively. However, surgical t raining and patient preparation are the keys to the safe use of topica l anesthesia.