THE DIAGNOSIS OF CUSHING'S SYNDROME USING131I-19-IODOCHOLESTEROL UPTAKE AND ADRENAL IMAGING

Abstract
Uptake measurements and visualization of the adrenal glands were performed using 131I-19-iodocholesterol in 10 healthy subjects and 14 patients suffering from Cushing''s syndrome (9 hyperplasias and 5 adenomas). The normal range in healthy subjects (averaged uptake value .+-. 2 SD [standard deviations]) is 0.12-0.27% for both adrenals. In patients with Cushing''s syndrome the uptake values ranged from 0.321-1.497%. Normal bilateral images were obtained in all the healthy subjects as well as in 8 of the patients with hyperplasia. The remaining patient with hyperplasia showed distinctly enlarged glands. An image of the diseased side only was obtained in patients with adrenal adenomas. Radiocholesterol studies in Cushing''s syndrome allow confirmation of the diagnosis, definition of the pathophysiologic type of disease and lateralization of adrenal adenomas.