1. Glaucoma Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
2. Faculty of Ophthalmology, College of Medicine, University of Ha’il, Ha’il, Saudi Arabia
3. Faculty of Ophthalmology, College of Medicine, Imam Abdulrahman bin Faisal university, Al Khobar, Saudi Arabia
4. Epidemiology Section, Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia