DETECTION AND SEGMENTAL LOCATION OF MALIGNANT HEPATIC-TUMORS - COMPARISON OF FERUMOXIDES-ENHANCED GRADIENT-ECHO AND T2-WEIGHTED SPIN-ECHO MR-IMAGING

OBJECTIVE. The aim of our prospective study was to compare the values of ferumoxides-enhanced gradient-echo and T2-weighted spin-echo MR ima ging for the detection and segmental location of malignant hepatic tum ors. SUBJECTS AND METHODS. Eighteen patients underwent ferumoxides-enh anced T2-weighted spin-echo and steady-state gradient-echo imaging bef ore surgery, Intraoperative sonography was used as the reference exami nation and showed 28 malignant tumors involving 39 of the 144 hepatic segments. The MR images were reviewed independently by two observers w ho recorded the number of tumors and their segmental location. The res ults of the segmental location were subjected to receiver-operating-ch aracteristic analysis. Tumor-liver, vessel-liver, and tumor-vessel con trast-to-noise ratios were calculated. RESULTS. Detection on the gradi ent-echo images did not differ significantly from that on the T2-weigh ted spin-echo MR images (observers A and B detected 23 and 24 tumors, respectively, on the gradient-echo images; the two observers each dete cted 22 tumors on the T2-weighted spin-echo images). Segmental localiz ation was significantly better on the gradient-echo images than on the T2-weighted spin-echo images (mean area under the receiver-operating- characteristic curve: 0.974 versus 0.895 for observer A and 0.962 vers us 0.906 for observer B, p =.024). The highest contrast-to-noise ratio s for vessel to liver and tumor to vessel were obtained on the gradien t-echo images and the highest tumor-liver contrast-to-noise ratio was obtained on the T2-weighted spin-echo images. CONCLUSION. In our study , ferumoxides-enhanced gradient-echo imaging was as accurate as T2-wei ghted spin-echo imaging for revealing malignant hepatic tumors and was superior for showing their segmental location.