1. Department of Neurosurgery, Oulu University Hospital, Oulu;
2. Research Unit of Clinical Neuroscience, Neurosurgery, Oulu University Hospital and University of Oulu;
3. Neurosurgery of KUH NeuroCenter, Kuopio University Hospital, and Faculty of Health Sciences, School of Medicine, Institute of Clinical Medicine, University of Eastern Finland, Kuopio;
4. Division of Surgery and Cancer Diseases, Department of Otorhinolaryngology–Head and Neck Surgery, Turku University Hospital, Turku Finland and University of Turku;
5. PEDEGO Research Unit, University of Oulu, MRC Oulu, and Department of Children and Adolescents, Oulu University Hospital, Oulu;
6. Department of Biomaterials Science, Institute of Dentistry, University of Turku and City of Turku, Welfare Division, Turku;
7. Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, Turku; and
8. Department of Neurology, University of Turku, Finland