title: Reply.
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
authors.forename: Arun
authors.initials: A
authors.lastname: Narayanaswamy
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore.
authors.forename: Mani
authors.initials: M
authors.lastname: Baskaran
authors.affiliation: Singapore Eye Research Institute and Singapore National Eye Centre, Singapore; Department of Ophthalmology, National University Hospital, National University Health System, Singapore. Electronic address: aung.tin@snec.com.sg.
authors.forename: Tin
authors.initials: T
authors.lastname: Aung