1 Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahi-Machi, Abeno-Ku, Osaka, 545-8585, Japan.
2 Department of Pediatrics, Detroit Medical Center, Children's Hospital of Michigan, Wayne State University, Detroit, MI, 48201, USA.
3 Department of Neurosurgery, Osaka Metropolitan University Graduate School of Medicine, 1-4-3 Asahi-Machi, Abeno-Ku, Osaka, 545-8585, Japan. udat@omu.ac.jp.
4 Department of Pediatric Neurosurgery, Osaka City General Hospital, 2-13-22 Miyakojimahondori, Miyakojima-Ku, Osaka, 534-0021, Japan. udat@omu.ac.jp.
5 Department of Pediatric Neurosurgery, Osaka City General Hospital, 2-13-22 Miyakojimahondori, Miyakojima-Ku, Osaka, 534-0021, Japan.