Daniel Shu Wei Ting1, Tien Yin Wong2. 1. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; Duke-NUS Medical School, National University of Singapore, Singapore. 2. Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; Duke-NUS Medical School, National University of Singapore, Singapore. Electronic address: ophwty@nus.edu.sg.