1. Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
2. Department of Neurosurgery, Oslo University Hospital – Rikshospitalet, Oslo, Norway
3. Center for Biomedical Computing, Simula Research Laboratory, Lysaker, Norway
4. Oslo Centre of Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, Oslo, Norway
5. Department of Mathematics, University of Oslo, Oslo, Norway
6. Department of Radiology, Oslo University Hospital – Rikshospitalet, Oslo, Norway