1. Department of Urology, Swansea Bay University Health Board, Swansea SA6 6NL, UK
2. Department of Urology, Imperial College Healthcare NHS Trust, London W6 8RF, UK
3. School of Medicine, Centre for Medical Engineering and Technology, University of Dundee, Dundee DD1 9SY, UK
4. Urological Surgery Department, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
5. Department of Urology & Nephrology, Dartford, and Gravesham NHS Trust, Dartford DA2 8DA, UK