Original PaperNon-invasive adrenal imaging in primary aldosteronism. Sensitivity and positive predictive value of radiocholesterol scintigraphy, CT scan and MRILUMACHI, F1; MARZOLA, M C2; ZUCCHETTA, P2; TREGNAGHI, A3; CECCHIN, D2; FAVIA, G1; BUI, F2Author Information 1Endocrine Surgery Unit, Department of Surgical and Gastroenterological Sciences, 2Nuclear Medicine Service and 3Radiology Unit, Department of Diagnostic Medical Sciences, University of Padua School of Medicine, 35128 Padova, Italy Address all correspondence to F. Lumachi, Endocrine Surgery Unit, Department of Surgical and Gastroenterological Sciences, University of Padua Medical School, via Giustiniani 2, 35128 Padova, Italy. Tel.: +39-049-821 2388. Fax: +39-049-656 145. e-mail: [email protected] Received 23 October 2002 and accepted 21 November 2002 Nuclear Medicine Communications: June 2003 - Volume 24 - Issue 6 - p 683-688 Buy Abstract The aim of this study was to evaluate the sensitivity and positive predictive value (PPV) of dexamethasone-suppression norcholesterol scintigraphy (NCS), computed tomography (CT) scanning and magnetic resonance imaging (MRI) in patients with primary aldosteronism (PA) who had undergone unilateral adrenalectomy. A series of 49 patients with confirmed PA was reviewed. There were 18 (36.7%) men and 31 (63.3%) women, with a median age of 47 years (range, 23-66 years). NCS was performed in all patients, and 46 (93.9%) and 31 (63.2%) underwent CT scan and MRI, respectively. Final pathology showed an aldosterone-producing adenoma in 45 (91.8%) patients, unilateral nodular cortical hyperplasia (NCH) in two (4.1%) and unilateral microscopic cortical hyperplasia (MCH) in two (4.1%). No aldosterone-producing carcinoma or bilateral adenomas were found. The greatest diameter of the removed adrenal tumour was in the range 8-40 mm (median, 14 mm). The PPV of adrenal imaging was 97.6% for NCS, 85.0% for CT scan (P = 0.04) and 83.3% for MRI (P = 0.03), and the sensitivity was 85.4%, 85.0% and 74.1%, respectively (P = NS). The age and the main biochemical parameters did not differ significantly (P = NS) between patients with true positive and false negative results of the imaging procedures. NCS accurately depicted all patients with NCH and MCH, whilst CT scan and MRI failed to diagnose such unilateral adrenal gland hyperfunction in two and three patients, respectively. The overall sensitivity of combined NCS and CT scan was 100%. In conclusion, in patients with PA, both NCS and CT scan are necessary to confirm the exclusive unilateral adrenal hyperfunction and, subsequently, to establish the appropriate treatment. © 2003 Lippincott Williams & Wilkins, Inc.