Comparative study of ultrasound, 131I-19-iodocholesterol scintigraphy, and aortography in localising adrenal lesions

Twenty-seven consecutive patients with endocrinological disease necessitating adrenal surgery underwent blind preoperative investigation with ultrasound, renal aortography, and adrenocortical scintigraphy for an adrenal lesion. Nine patients had pituitary-dependent Cushing's syndrome, five had pituitary-independent Cushing's syndrome, four had an adrenocortical androgenic excess, and nine had a preoperative diagnosis of phaeochromocytoma. The predictive value of preoperative ultrasound was 100% for a positive finding and 79% for a negative result. Preoperative aortography had a predictive value of 83% for a positive finding and 64% for a negative result; and the predictive value of adrenocortical scintigraphy was 100% for a positive finding and 85% for a negative finding. In localising biochemically suspected adrenal lesions ultrasound should be the first choice, since it is rapid, noninvasive, cheap, and reasonably accurate. Adrenocortical scintigraphy has a similar diagnostic value, especially in Cushing's syndrome, but it is time consuming. Nevertheless, it may be preferable for diagnosing small glucocorticoid-secreting adenomas. Aortography should be reserved for cases with inconclusive diagnoses and suspected extra-adrenal phaeochromocytomas.