1. Department of Surgery/Otolaryngology; UCSD School of Medicine and Veterans Administration Medical Center; La Jolla CA 92093-0666 U.S.A.
2. Department of Otolaryngology—Head and Neck Surgery; Julius-Maximilians-Universität; 97080 Würzburg Germany
3. Department of Neurosciences; UCSD School of Medicine and Veterans Administration Medical Center; La Jolla CA 92093-0666 U.S.A.