1 Department of Ophthalmology, United Christian Hospital, Kowloon East Cluster, Hong Kong; Department of Ophthalmology, Tseung Kwan O Hospital, Kowloon East Cluster, Hong Kong.
2 Department of Medicine and Geriatrics, United Christian Hospital, Kowloon East Cluster, Hong Kong.
3 Department of Pathology, United Christian Hospital, Kowloon East Cluster, Hong Kong.
4 Department of Ophthalmology, United Christian Hospital, Kowloon East Cluster, Hong Kong; Department of Ophthalmology, Tseung Kwan O Hospital, Kowloon East Cluster, Hong Kong. Electronic address: kennethli@rcsed.ac.uk.