Manifest glaucoma in the aged I: occurrence nine years after a population survey.

The present study was based on already existing clinical data concerning 599 persons born before 1907, examined during a general ophthalmic survey 1969-72 and still remaining in the same district in July 1980. At the survey 1969-72, 19 out of 1057 persons had manifest glaucoma, 14 were already treated for ocular hypertension, 54 had an IOP greater than 20.5 mmHg and 970 were considered normal. Immediately after the survey, 17 patients were treated for manifest glaucoma and 19 for ocular hypertension. During the following 9 years treated persons were lost to a greater extent (64%) than untreated persons (43%). In July 1980 only 6 persons treated for manifest glaucoma since the survey remained, and 3 of them were socially blind. One out of 7 treated and 2 out of 28 untreated persons with ocular hypertension at the survey had developed visual field defects 9 years later. Manifest glaucomas, often advanced cases, were also detected in 9 persons considered normal at the survey. 5 out of 12 persons with manifest glaucoma detected after the survey had an IOP less than 20.5 mmHg at detection. The visual capacity of persons still remaining in the district 1980 was largely independent of all efforts to prevent blindness from glaucoma in the present population.