1. Department of Pediatrics, Juntendo University School of Medicine, Tokyo, Japan
2. Department of Pediatrics, Anjo Kosei Hospital, Anjo, Japan
3. Department of Pediatrics, Juntendo Urayasu Hospital, Urayasu, Japan
4. Department of Pediatrics, University of Tokyo, Tokyo, Japan
5. Department of Pediatrics, Chiba University Graduate School of Medicine, Chiba, Japan
6. Department of Radiology, Teikyo University Hospital, Tokyo, Japan