Kai Xiong Cheong1, Colin S H Tan2,3. 1. National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore. 2. National Healthcare Group Eye Institute, 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.