Ultrasonography in the diagnosis of aldosterone-producing adenoma: is it useful?

The usefulness of ultrasonography (US) in the diagnosis of aldosterone-producing adenoma(s) (APA) was compared with computed tomography (CT) and adrenal scintigraphy in 13 patients. The initial examination with US could demonstrate four of seven right APA. Repeat examinations later in two patients whose tumors were initially not detectable did reveal a tumor in one patient. On the other hand, two left APA were delineated on the initial trial. The other seven left APA, except two small APA in one patient, could be delineated during repeat US examinations performed on other days. With CT, all APA were detected during the first or second trial except for the smallest one. The rate of localization by adrenal scintigraphy with dexamethasone pretreatment was 11 of 13 patients. CT had the highest localization rate. However, US was shown to be useful in the localization diagnosis of APA on repeat examinations with a high delineation rate comparable to CT.