1. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
2. Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Shatin, Hong Kong
3. Department of Ophthalmology and Visual Sciences, Hong Kong Eye Hospital, Kowloon, Hong Kong
4. Department of Ophthalmology, Caritas Medical Centre, Sham Shui Po, Hong Kong