1. Department of Radiology, Southend University Hopsital NHS Foundation Trust, Southend, United Kingdom
2. Department of Radiology, Norfolk and Norwich University Hospital NHS Foundation Trust, Norwich, United Kingdom
3. Department of Radiology, St. Bartholomew’s and the Royal London NHS Foundation Trust, London, United Kingdom
4. Neuroscience and Vascular Simulation Unit, Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, United Kingdom