1 Children's Clinic, St Olavs Hospital University Hospital in Trondheim, Trondheim, Norway martin.leth-olsen@ntnu.no.
2 Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, NTNU-Norwegian University of Science and Technology, Trondheim, Norway.
3 Department of Paediatric Surgery, St Olavs Hospital University Hospital in Trondheim, Trondheim, Norway.
4 Children's Clinic, St Olavs Hospital University Hospital in Trondheim, Trondheim, Norway.