Hepatic lesion detection at MR imaging: A comparative study with four sequences

PURPOSE: To compare results with the following magnetic resonance (MR) imaging sequences in the detection of focal hepatic lesions: fast spin-echo (SE) before and after administration of superparamagnetic iron oxide (SPIO) particles, fat-suppressed T2-weighted SE, and dynamic gadolinium-enhanced fast low-angle shot (FLASH). MATERIALS AND METHODS: In 26 patients with known malignancy and documented focal liver lesions, 1.0-T MR imaging was performed prior to hepatic resection. All images were reviewed independently by four blinded observers. Sensitivity was calculated for each sequence and for each observer by means of alternative-free-response receiver operating characteristic (ROC) methods. RESULTS: The mean area under the alternative-free-response ROC curve with SPIO-enhanced fast SE (0.85) was significantly greater (P < .02) than that with all other Sequences. Detection was significantly improved with SPIO-enhanced fast SE compared with dynamic gadolinium-enhanced FLASH (which was the best of the other three sequences) for all lesions (P < .002) and for malignant lesions (P < .0002). CONCLUSION Findings with the SPIO-enhanced fast SE sequence improved detection of focal liver lesions and had the highest diagnostic accuracy.