1 Division of Neurosurgery, Department of Surgery, University of Toronto, Canada; Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada.
2 Division of Neurosurgery, McGill University, Montreal, Quebec, Canada.
3 University Health Network, Toronto, Ontario, Canada.
4 University Health Network, Toronto, Ontario, Canada; Joint Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada.
5 Division of Neurosurgery, Department of Surgery, University of Toronto, Canada; University Health Network, Toronto, Ontario, Canada.
6 Division of Neurosurgery, Department of Surgery, University of Toronto, Canada; Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada. Electronic address: george.ibrahim@sickkids.ca.