1. Department of Otolaryngology and Bronchoesophagology, Rush University Medical Center, Chicago, Illinois
2. Department of Otolaryngology, Advanced Center for Specialty Care, Advocate, Illinois Masonic Medical Center, Chicago, Illinois
3. Department of Otolaryngology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan