1. Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong
2. Department of Ophthalmology, Tung Wah Eastern Hospital, Hong Kong
3. Faculty of Medicine, Chinese University of Hong Kong, Hong Kong
4. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
5. Clarity Eye and Surgery Centre, Kowloon, Hong Kong
6. Department of Ophthalmology and Visual Sciences, Hong Kong Eye Hospital, Hong Kong
7. Dacryology Service, LV Prasad Eye Institute, Hyderabad, India