Retrobulbar (intraconal) anesthesia with a curved needle: technique and results

We report the results of two prospective studies of retrobulbar anesthesia using curved 25 mm and 28 mm needles. These studies were prompted by our experience with the 25 mm needle in more than 13,000 cases of intraconal anesthesia in which one case of postoperative ischemic neuropathy was the only complication. The technique involves the transcutaneous introduction of the curved needle at the middle of the lower lid, following a curved track close to the inferior orbital wall, around the globe, parallel to the plane of the medial orbital wall (i.e., in a strictly sagittal plane lateral to the optical axis in primary gaze). No complications were noted in the prospective studies. Side effects were chemosis in 30% of cases, subconjunctival hemorrhage in 5%, and lid hemorrhage in 2%. Since these comparative studies, we have used the 28 mm needle without significant complications in more than 8,000 cases. This method of retrobulbar anesthesia is superior to peribulbar anesthesia, and because of its safety and reliability, is preferable.