The prevalence and implications of ocular hypertension and glaucoma in thyroid-associated orbitopathy

Purpose: The authors determined the prevalence of ocular hypertension and its association with progression to glaucomatous damage in patients with thyroid-associated orbitopathy (TAO). Methods: The charts of 500 consecutive patients with TAO seen at the Allegheny General Hospital (Pittsburgh, PA) between 1985 and 1995 were analyzed, The amount of proptosis, degree and duration of myopathy, exposure to corticosteroids, prior glaucoma treatment, and family history of glaucoma were evaluated. Results: One hundred twenty (24%) patients with TAO were noted to have an intraocular pressure (IOP) greater than 22 mmHg but less than 30 mmHg. This ocular hypertensive group was composed of 34 men and 86 women with a mean age of 55 years and mean follow-up of 4 years. Seven patients were defined as glaucoma suspects, based on increased but nonprogressive cup-to-disc ratios or nonprogressive, atypical visual field changes in the presence of increased IOP. Two patients demonstrated progressive visual field abnormalities and cupping, Of the factors evaluated, only the duration of active orbital involvement was statistically associated with progression to glaucomatous damage. The mean duration of TAO was 3, 8, and 12 years for ocular hypertensives, glaucoma suspects, and glaucomatous damage, respectively, Conclusions: Only a prolonged duration of active TAO in association with ocular hypertension correlated with progression to glaucomatous damage, These patients with chronic TAO deserve special attention and close follow-up to prevent optic nerve damage.