Ocular hypertension--a long-term follow-up of treated and untreated patients.

Sixty-one patients with ocular hypertension (1 17 eyes) were followed up for I to 11 years (average 40 7 months). Ten patients (12 eyes) developed visual field defects and optic disc lesions of glaucomatous type ( 10 2 %). Their average age was lower than the average of the sample, and the defect appeared between 1 and 5 years (average 41 3 months). The risk of developing glaucoma was related to the level of the intraocular pressure. Of the 75 eyes with pressures between 21 and 25 mmHg only 2 developed glaucoma, of the 25 cases with pressures of 26 to 30 only 3, but 7 of the 17 eyes with pressures of 31 mmHg or more did so. Prophylactic cryosurgery was carried out where indicated by the presence of lattice retinal degeneration or holes before starting miotic therapy. Fifty eyes were given antiglaucoma therapy and compared with 67 eyes not treated. Treatment did not prevent the development of glaucoma and did not seem to influence the course of the ocular hypertension. The response to treatment was also valueless in predicting future glaucoma. Two untreated patients with high pressures developed central vein occlusion. As no harmful effect of treatment could be detected in the 50 treated eyes, elderly patients (more than 70 years) with intraocular pressure higher than 26 mmHg in the presence of systemic vascular disease should have their intraocular pressure lowered if possible before the development of field defects. In those with intraocular pressure below 26 mmHg there is no advantage in prescribing treatment. In the range 26 to 30 mmHg it is our practice to treat elderly patients over the age of 70 years, while younger patients are treated only if their intraocular pressure exceeds 30 mmHg.