Visual-evoked potentials: Assessment of retrobulbar and peribulbar anesthesia

Purpose: To assess the effects of retrobulbar and peribulbar anesthesia on nerve function as detected by visual-evoked potentials (VEPs). Setting: University hospital in southern Brazil. Methods: in a prospective study, 7 patients had peribulbar anesthesia and 9 had retrobulbar anesthesia for extracapsular cataract extraction. Visual-e voked potentials with pattern reversal and flash stimulation were performed at least 1 month before and 1 month after surgery. Study participants did not have ocular pathology other than cataract. The Lens Classification Syst em III was used to grade the opacities before surgery. Results: No significant difference was found between preoperative and posto perative evaluations in VEP flash and pattern-reversal amplitude and latenc y in either group (P > .05). Postoperative amplitude and latency was not si gnificantly different between the peribulbar and retrobulbar groups. Two ca ses in the peribulbar group had altered wave morphology without clinical ma nifestation postoperatively. All patients had a final best spectacle-correc ted visual acuity of 20/20. Conclusion: Block anesthetic procedures were safely used in cataract surger y,with no clinical sequelae to the optic nerve. J Cataract Refract Surg 200 0; 26:1529-1532 (C) 2000 ASCRS and ESCRS.