1. Department of Otolaryngology-Head and Neck Surgery; Wexner Medical Center at The Ohio State University; Columbus Ohio U.S.A.
2. Department of Otolaryngology-Head and Neck Surgery; Wake Forest Baptist Medical Center; Winston Salem North Carolina U.S.A.
3. Department of Otolaryngology; German Hospital of Santiago; Santiago Chile
4. Department of Neurosurgery; Wexner Medical Center at The Ohio State University; Columbus Ohio U.S.A.