1. Department of Diagnostic Radiology, University of Toronto, 263 McCaul St, 4th Fl, Toronto, ON M5T 1W7, Canada.
2. Department of Diagnostic Radiology, QEII Health Sciences Centre, Dalhousie University, Halifax, NS, Canada.
3. Department of Diagnostic Radiology, London Health Sciences Centre, Western University, London, ON, Canada.
4. Department of Diagnostic Radiology, McGill University Health Centre, McGill University, Montreal, QC, Canada.
5. Department of Diagnostic Radiology, Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada.
6. Department of Cardiovascular and Interventional Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
7. Department of Radiology, Foothills Medical Centre, Calgary, AB, Canada.