1. Department of Surgical Sciences, Eye Clinic, University of Cagliari, Via Ospedale 48, 09124 Cagliari, Italy
2. Department of Ophthalmology, University ‘Magna Græcia’ of Catanzaro, Viale Europa, 88100 Catanzaro, Italy
3. Department of Ophthalmology, Broomfield Hospital, Chelmsford CM1 7ET, UK
4. Department of Ophthalmology, Southend University Hospital, Southend-on-Sea SS0 0RY, UK