1. Department of Surgical, Microsurgical, and Medical Sciences; Ophthalmology Unit; University of Sassari; Sassari Italy
2. Azienda Ospedaliero-Universitaria di Sassari; Sassari Italy
3. Department of Biomedical Sciences; Section of Clinical Biochemistry; University of Sassari; Sassari Italy
4. Department of Biomedical Sciences; Laboratory of Epidemiology and Biostatistics; University of Sassari; Sassari Italy