1. Vanderbilt University Medical Center Dept. of Otolaryngology and Pulmonology; Nashville Tennessee
2. Baylor College of Medicine Dept. of Otolaryngology; Houston Texas
3. Imperial College Healthcare NHS Trust Dept. of Otolaryngology; London United Kingdom
4. Cleveland Clinic Dept. of Otolaryngology; Cleveland Ohio
5. Johns Hopkins University Dept. of Otolaryngology; Baltimore Maryland
6. Mayo Clinic Dept. of Otolaryngology and Pulmonology; Rochester Minnesota
7. Oregon Health and Science University Dept. of Otolaryngology; Portland Oregon
8. University of Utah School of Medicine Dept. of Otolaryngology; Salt Lake City Utah
9. University of Virginia Health System Dept. of Otolaryngology; Charlottesville Virginia U.S.A.