1. National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore
2. Department of Ophthalmology, Faculdade de Medicina and Hospital São Geraldo/Hospital das Clínicas da Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
3. Medical Research Foundation, Sankara Netralaya, Chennai, Tamil Nadu, India
4. Eagle Eye Centre, Mt Alvernia Hospital, Singapore, Singapore