1. Department of Ophthalmology, Trauma Centre, St. Barbara Hospital, 41-200 Sosnowiec, Poland
2. Optegra Clinic in Katowice, 40-101 Katowice, Poland
3. Collegium Medicum, WSB University, 41-300 Dabrowa Gornicza, Poland
4. Optegra Clinic in Poznań, 61-101 Poznań, Poland
5. Clinical Department of Ophthalmology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 40-760 Katowice, Poland
6. Department of Ophthalmology, District Railway Hospital, 40-760 Katowice, Poland
7. Optegra Clinic in Krakow, 30-347 Krakow, Poland
8. Department of Ophthalmology, Central Clinical Hospital of the Ministry of National Defense, Military Institute of Medicine in Warsaw, 04-141 Warsaw, Poland
9. Optegra Clinic in Warszawa, 02-366 Warszawa, Poland