Affiliation: | 1. Department of Internal Medicine, Institute of Digestive Disease and Nutrition, Korea University College of Medicine, Seoul, South Korea;2. Department of Anatomy, Korea University College of Medicine, Seoul, South Korea;3. Department of Otolaryngology–Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea;4. Department of Internal Medicine, Kangwon National University College of Medicine, Chuncheon‐si, Gangwon, South Korea |