1. Department of Pediatrics; Yamanashi Prefectural Central Hospital; Yamanishi Japan
2. Department of Pediatrics, Faculty of Medicine; University of Yamanashi; Yamanishi Japan
3. Department of Pediatric Surgery; Yamanashi Prefectural Central Hospital; Yamanishi Japan
4. Department of Otorhinolaryngology; Yamanashi Prefectural Central Hospital; Yamanishi Japan