Kai Xiong Cheong1, Colin S Tan2,3. 1. Singapore National Eye Centre, Singapore Health Services, Singapore, Singapore. 2. Department of Ophthalmology, Tan Tock Seng Hospital, Singapore, Singapore. Colintan_eye@yahoo.com.sg. 3. Fundus Image Reading Center, National Healthcare Group Eye Institute, Singapore, Singapore. Colintan_eye@yahoo.com.sg.