1. Department of Radiology, Toho University Ohashi Medical Center; Tokyo, Japan
2. Department of Radiology, National Center for Child Health and Development; Tokyo, Japan
3. Department of Neurosurgery, Kyorin University; Tokyo, Japan
4. Department of Radiology, Fujisawa Municipal Hospital; Fujisawa, Japan
5. Department of Pediatrics, Fujisawa Municipal Hospital; Fujisawa, Japan