Computed Tomography and Radioisotopic Study in the Diagnosis of the Adrenal Diseases

The normal appearance of the adrenal glands on computed tomography (CT) was evaluated. The roles of CT and radioisotopic (RI) study in adrenal tumor detection were compared. On the 50 normal cases, bilateral adrenal glands were identified by CT in 42 (84%). The margins of the normal glands were straight or concave. Seven cases of pheochromocytoma, 5 cases of Cushing's syndrome, 5 cases of primary aldosteronism and 4 cases of metastatic adrenal tumor were evaluated. CT is the first choice of examination in the localization of a pheochromocytoma. CT and RI study can play important roles in localizing cortisol-secreting tumor. CT and RI study should be the initial investigation for the localization of aldosterone-secreting adenoma. However, as the adenoma may be quite small, tests other than CT and RI study may be required. The change in the margin of the gland is valuable criterion for adenoma on CT. CT is also useful for metastatic adrenal tumors. CT and RI study are easy to perform and noninvasive, and recommended as the radiographic procedure in the evaluation of adrenal tumors.