Role of preoperative iodocholesterol scintiscanning in patients undergoing adrenalectomy for Cushing's syndrome.

Abstract

Iodocholesterol scintiscanning (IS) is a noninvasive, functional diagnostic test. We report our experience with IS as an adjunct for adrenal surgery for Cushing's syndrome. Between April 1983 and October 1994, 23 patients with Cushing's syndrome from benign primary adrenal disease underwent IS and computed tomography (CT) and/or magnetic resonance imaging (MRI). Twelve patients had unilateral adrenal involvement with a solitary adenoma (n = 11) or unilateral multinodular disease (n = 1), and 11 patients had bilateral adrenal disease. In patients with Cushing's syndrome caused by unilateral adrenal disease, IS was 100% specific and 100% sensitive, whereas in two cases CT/MRI incorrectly showed bilateral disease. In patients with Cushing's syndrome with bilateral adrenal involvement, IS had one false-negative result with nonvisualization. CT/MRI showed unilateral disease in four cases and no abnormalities in two. All patients in this series were cured of Cushing's syndrome after unilateral adrenalectomy in 11 cases and bilateral adrenalectomy in 12 cases. IS is a highly sensitive and specific imaging modality and is an essential adjunct to biochemical testing in planning adrenal resections for Cushing's syndrome caused by primary adrenal disease.