1. Department of Otolaryngology Head and Neck Surgery, University of Minnesota, Minneapolis, Minnesota, USA.
2. University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, USA.
3. Department of Hyperbaric Medicine, Hennepin County Medical Center, Minneapolis, Minnesota, USA.
4. Department of Ear, Nose, Throat and Facial Plastic Surgery, Children's Minnesota, Children's Specialty Center, Minneapolis, Minnesota, USA.