[1] Manchester Royal Eye Hosp, Dept Ophthalmol, Manchester M13 9WL, Lancs, England
[2] Natl Specialist Ophthalm Pathol Serv, Dept Histopathol, Manchester, Lancs, England
[3] Chinese Univ Hong Kong, Dept Ophthalmol & Visual Sci, Kowloon, Hong Kong, Peoples R China