1 Department of Pediatrics, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-0034, Japan.
2 Department of Pediatrics, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-0034, Japan. Electronic address: s.baba.ped@gmail.com.
3 Department of Radiology, Tokyo Medical and Dental University, Bunkyo, Tokyo, Japan.
4 Department of Pediatrics, Tokyo Medical and Dental University, Bunkyo, Tokyo, Japan.