1. Department of Otolaryngology—Head and Neck Surgery University of Cincinnati College of Medicine Cincinnati Ohio U.S.A.
2. Department of Otolaryngology Harvard Medical School Boston Massachusetts U.S.A.
3. Division of Otolaryngology Beth Israel Deaconess Medical Center Boston Massachusetts U.S.A.
4. Department of Otolaryngology Massachusetts Eye and Ear Infirmary Boston Massachusetts U.S.A.