1. Jones Eye Institute, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
2. Department of Ophthalmology, Scheie Eye Institute, Philadelphia, Pennsylvania, USA
3. Department of Ophthalmology, Moorfields Eye Hospital, London, UK
4. UCL Institute of Ophthalmology, University College London, London, UK
5. Department of Infectious Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
6. Department of Ophthalmology, Ain Shams University, Cairo, Egypt