1. Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK
2. Department of Corneal and External Eye Diseases, St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
3. Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
4. Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania Luigi Vanvitelli, Naples, Italy
5. Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
6. Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
7. Moorfields Eye Hospital NHS Foundation Trust, London, UK
8. Department of Ophthalmology, Ankara University School of Medicine, Mamak Street Vehbi Koç Eye Hospital, Dikimevi, Ankara, Turkey
9. Unidad oftalmologia, departamento especialidades, Facultad de Medicina, Universidad de la Frontera, Temuco, Chile
10. Department of Biomedical Sciences, Humanitas University, Pieve Emanuele - Milano, Italy
11. Department of Ophthalmology, Humanitas Gavazzeni-Castelli, Bergamo, Italy