1. Health Education and Improvement Wales’ School of Surgery, Nantgarw, UK
2. Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Treforest, UK
3. Department of Surgery, University Hospital of Wales, Cardiff, UK
4. Department of Surgery, Morriston Hospital, Swansea, UK
5. School of Medicine, Swansea University, Swansea, UK