1. University of Oslo, Oslo Urological University Clinic, Aker University Hospital, Oslo, Norway.
2. Department of Urology, St. Olavs Hospital/University Hospital of Trondheim, Trondheim, Norway.
3. Norwegian University of Technology and Science, St. Olavs Hospital/University Hospital of Trondheim, Trondheim, Norway.
4. The Research Center, Aker University Hospital, Oslo, Norway.