1. Brain and Circulation Research Group, Department of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
2. Department of Ophthalmology, Nordland Hospital, Bodø, Norway
3. Research Group of Epidemiology of Chronic Diseases, Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
4. Department of Ophthalmology and Neurosurgery, University Hospital of North Norway, Tromsø, Norway
5. Department of Ophthalmology, Odense University Hospital, Odense, Denmark
6. Department of Neurology and Neurophysiology, University Hospital of North Norway, Tromsø, Norway