1. MD, Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok 10330, Thailand
2. Department of Ophthalmology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
3. Department of Ophthalmology, King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand