Peritoneal tumor: MR imaging with dilute oral barium and intravenous gadolinium-containing contrast agents compared with unenhanced MR imaging and CT.

Abstract

To compare fat-suppressed, gadolinium-enhanced, breath-hold magnetic resonance (MR) imaging after administration of dilute oral barium solution with unenhanced MR imaging and computed tomography (CT) in the detection of peritoneal tumors. In 24 patients in whom peritoneal tumor was known or suspected, double-contrast MR imaging and CT were performed prospectively. MR imaging included T1-weighted, fast spin-echo T2-weighted, and immediate and delayed gadolinium-enhanced, breath-hold, fast multiplanar sequences with fat saturation. Helical and conventional dynamic CT were performed with intravenously and orally administered contrast media. MR images and CT scans were reviewed independently and prospectively by different pairs of radiologists for presence of peritoneal tumor in 17 anatomic sites. Imaging findings were compared with surgical and histopathologic results. Of the 24 patients, 18 had peritoneal tumor confirmed at surgery. Detection of tumor sites was superior with double-contrast MR images (mean sensitivity, specificity, and accuracy, 84%, 87%, and 86%, respectively) compared with CT scans (mean sensitivity, specificity, and accuracy, 54%, 91%, and 74%, respectively). Double-contrast MR imaging enabled better detection of carcinomatosis and tumors less than 1 cm in diameter (75%-80%) than CT (22%-33%; P < .0001). Double-contrast MR imaging demonstrated more peritoneal tumors than CT or unenhanced spin-echo MR imaging.