About the Volume Editors:Kieran Murphy, MD is Vice Chair and Vice Chief of Radiology and Medical Imaging at the University of Toronto, and Chair of the Advisory on the technology transfer offices and commercialization of intellectual property for the university health network. Previous positions include the Director of Interventional Neuroradiology at Johns Hopkins Hospital, and Director of Research in the neuroradiology section of the Albany Medical College in New York. His research focuses on the use of imaging techniques to guide surgical intervention, particularly brain aneurysms and carotid artery disease. Fergus Robertson, MD is a Consultant Neuroradiologist at the National Hospital for Neuroradiology and Neurosurgery (part of University College London Hospital). He is a well-known expert in the field.