THE territory's first study on glaucoma, the second most common eye complaint to cause blindness, is shedding light on the spread of the disease. The report, to be completed in February, will reveal the pattern of glaucoma and examine its relationship with diabetes. About 4,000 people aged 50 and over were screened in a four-month programme which ended last week at Evangel Hospital, Kowloon City. Preliminary findings showed more than 900 people - or almost a quarter - were 'suspicious cases' who might have the disease which increases pressure within the eyeball and impairs sight. Evangel's medical director Dr Lam Ching-choi said the true number affected would be whittled down by more tests. International statistics on glaucoma reveal there is an 1:100 incidence for people aged over 50. The number jumps to 1:50 for the group aged above 60, and Hong Kong is thought to share the pattern.