Brigitte Maria Happel MD, Presenter: Nothing to Disclose

Thomas Georg Mang MD, Abstract Co-Author: Nothing to Disclose

Wolfgang Matzek MD, Abstract Co-Author: Nothing to Disclose

Bruno Niederle MD, Abstract Co-Author: Nothing to Disclose

Klaus Kaserer MD, Abstract Co-Author: Nothing to Disclose

Gertraud Heinz-Peer MD, Abstract Co-Author: Nothing to Disclose

PURPOSE: To compare the diagnostic performance of MDCT and MRI in characterization of adrenal masses and to compare imaging findings with histopathologic results.

MATERIALS AND METHODS: 25 patients (8m, 17f, mean age 52y) underwent MDCT and MRI for evaluation of adrenal masses. CT was performed on either a 4 or 16 row scanner (Siemens). CT protocol included unenhanced scans, 1 min post contrast and 15 min delayed contrast enhanced series. All MR examinations were performed on a 1.5T unit (Siemens). MR protocol included chemical shift and Gd-enhanced dynamic imaging with delayed contrast enhanced series. CT- and MR images were independently reviewed by two radiologists, experienced in adrenal gland imaging, and blinded to patients' history. CT and MRI findings were compared to histologic results in all cases.

RESULTS: 26 adrenal masses (bilateral in 1 patient) were detected on MDCT and MRI (mean size 32mm, range 8-86mm). Histology revealed 17 adenomas, 5 pheochromocytomas and 4 metastases. On MRI 15/17 adenomas, 4/5 pheochromocytomas and 4/4 metastases were correctly diagnosed. In two atypical adenomas MR imaging findings were indicative for malignant lesions. Overall sensitivity for MRI was 88,5%. On MDCT 17/17 adenomas, 3/5 pheochromocytomas and 4/4 metastases were correctly diagnosed. Overall sensitivity was 92,3%.

CONCLUSION: Both, MDCT and MRI have high sensitivity in characterization of adrenal masses. MDCT seems to be more reliable in evaluation of atypical adenomas compared to MR imaging. In characterization of pheochromocytomas the diagnostic performance of CT and MRI can be improved by knowledge of the clinical history.

Happel, B, Mang, T, Matzek, W, Niederle, B, Kaserer, K, Heinz-Peer, G, Comparison of MDCT and MRI in Characterization of Adrenal Masses.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4411377.html