1. Division of Neuroradiology, University of Calgary, Calgary, AB, Canada
2. Department of Radiology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
3. Department of Radiology, QEII Health Science Centre, Halifax Infirmary Hospital, Dalhousie University, Halifax, NS, Canada
4. Department of Mechanical Engineering, University of Calgary, Calgary, AB, Canada
5. Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
6. Division of Radiation Oncology, University of Calgary, Calgary, AB, Canada