1. Department of Health, Medicine and Caring Sciences, Linköping University , Building 511, Entrance 75, Room 13.1309 Campus US, 581 83 Linköping , Sweden
2. Department of Biomedical Engineering, Linköping University , Linköping , Sweden
3. Perimed AB, Järfälla , Stockholm , Sweden
4. Centre of Medical Image Science and Visualization (CMIV), Linköping University , Linköping , Sweden