1. Department of Neurosurgery, Yokohama City University School of Medicine, Yokohama, Kanagawa, Japan
2. Division of Neuroradiology, Department of Medical Imaging, Joint Department of Medical Imaging, University Health Network and Toronto Western Hospital, University of Toronto, ON, Canada
3. Department of Neuroradiology, National Neuroscience Institute, Singapore
4. Division of Neurosurgery, Sprott Department of Surgery, Toronto Western Hospital, University of Toronto, ON, Canada