Detection of liver metastases: comparison of superparamagnetic iron oxide-enhanced and unenhanced MR imaging at 1.5 T with dynamic CT, intraoperative US, and percutaneous US.

Abstract

To compare the sensitivities of superparamagnetic iron oxide-enhanced and unenhanced magnetic resonance (MR) imaging at 1.5 T with those of percutaneous ultrasound (US), intraoperative US (IOUS), and dynamic computed tomography (CT) in the preoperative assessment of metastatic liver disease. Eighteen patients with liver metastases who were candidates for curative surgery underwent presurgical imaging. Thirteen patients underwent surgery and IOUS after undergoing preoperative US, CT, and MR imaging. In the preoperative imaging group, the standard of reference was the total number of lesions detected with any of the modalities. Superparamagnetic iron oxide-enhanced MR imaging was the most sensitive modality (99%). In the surgical group, the standard of reference was the total number of metastases identified at IOUS and pathologic examination. IOUS had the highest sensitivity (80%), followed by superparamagnetic iron oxide-enhanced MR imaging (56%). Superparamagnetic iron oxide-enhanced high-field-strength MR imaging facilitates the preoperative evaluation of potentially curable metastatic liver disease; however, it is inferior to IOUS.