1. Department of Otolaryngology–Head & Neck Surgery University of Utah School of Medicine Salt Lake City Utah USA
2. Department of Radiology National Jewish Health Denver Colorado USA
3. Department of Otolaryngology–Head & Neck Surgery Oregon Health Sciences University Portland Oregon USA
4. Department of Otolaryngology–Head & Neck Surgery Medical University of South Carolina Charleston South Carolina USA
5. Department of Otolaryngology–Head & Neck Surgery Indiana University School of Medicine Indianapolis Indiana USA