1. Department of Otolaryngology-Head and Neck Surgery; University of Texas Health Science Center San Antonio; San Antonio Texas U.S.A
2. Department of Anesthesiology; University of Texas Health Science Center San Antonio; San Antonio Texas U.S.A
3. Department of Otolaryngology; Massachusetts Eye and Ear Infirmary; Boston Massachusetts U.S.A
4. Department of Surgery; Uniformed Services University; Bethesda Maryland U.S.A