1. Department of Ophthalmology; Kymenlaakso Central Hospital; Kotka Finland
2. Helsinki Retina Research Group; University of Helsinki; Helsinki Finland
3. Patient Insurance Centre; Helsinki Finland
4. Tays Eye Centre; Tampere University Hospital; Tampere Finland
5. Department of Ophthalmology; Kuopio University Hospital; Kuopio Finland
6. Department of Ophthalmology; Institute of Clinical Medicine; University of Eastern Finland; Kuopio Finland