1. Research Unit of Clinical Medicine and Medical Research Center, Department of Ophthalmology, Oulu University Hospital and University of Oulu, 90029 Oulu, Finland
2. Medical Research Center, PEDEGO Research Unit, Department of Ophthalmology, Oulu University Hospital and University of Oulu, 90029 Oulu, Finland
3. Research Service Unit, 90220 Oulu, Finland
4. The Research Unit of Surgery, Anesthesia and Intensive Care, Oulu University Hospital and University of Oulu, 90029 Oulu, Finland