Exophthalmos and iatrogenic Cushing's syndrome.
A 38-year-old physician presented with a 9-month history of progressive self-administration of oral prednisone < or = 160 mg per day for Addison's disease. Examination demonstrated typical Cushingoid features and bilateral proptosis with elevated intraocular pressure. Computed tomography disclosed increased intraorbital adipose tissue. We hypothesize that the increased intraorbital adipose deposition was due to the differential binding of glucocorticoids to adipose tissue receptors and an enhancement of lipoprotein lipase activity. We conclude that the findings in this case may be related to glucocorticoid-induced changes in the ocular and periorbital structures. Cushing's syndrome should be considered in the differential diagnosis of acquired exophthalmos and elevated intraocular pressure and findings of increased orbital fat on orbital imaging.