1. Department of Radiology, Service of Neuroradiology, Centre Hospitalier de l’Université de Montréal (CHUM), Montreal, Quebec, Canada
2. Department of Neuroradiology, Service de Neuroradiologie Diagnostique et Thérapeutique du CHU de Toulouse, University Hospital of Toulouse, Toulouse, France
3. Department of Neurological Surgery, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
4. Department of Surgery, Division of Neurosurgery, University of Alberta hospital, Mackenzie Health Sciences Center, Edmonton, Alberta, Canada