Comparison of Conventional Spin Echo, Fast Spin Echo and Fast Multiplanar Spoiled Gradient Recalled Imaging for Evaluation of Focal Hepatic Lesions

ABSTRACT

PURPOSE: To compare the detectability and conspicuity of focal hepatic lesions among conventional spin echo techniqueniques and fast scanning techniqueniques in MR imaging. MATERIALS AND METHOD: 36 patients (24 men and 12 women, mean age of 54 years) with suspected liver mass on CT scan and US underwent MR imaging at 1.5 T system. Conventional spin echo T1, T2 weighted imaging, T2 weighted fast spin echo, T1 weighted fast multiplanar spoiled gradient recalled(FMPSPGR) imaging and Gd-enhanced FMPSPGR(Gd-FMPSPGR) were performed. 16 cases of hepatocellular carcinoma, 13 cases of hemangioma, 3 cases of metastasis, 3 cases of cholangiocarcinoma, and 1 case of lymphoma were included. Lesion conspicuity and number of detected hepatic masses were compared among the MR sequences. RESULTS: Overall 63 hepatic lesions were detected in 36 patients. Lesion detection' was 63(100%) with Gd-FMPSPGR, 62(98%) with non-enhanced FMPSPGR, 58(92%) with SE T2WI, 56(89%) with SE T1WI and 54 (86%)with FSE. For solid tumors, the contrast to noise ratio was greatest on Gd-FMPSPGR which was significantly higher than any other sequences. For hemangiomas it was greatest on SE T2WI and was significantly higher than SE T1WI. In the qualitative assessment, Gd-FMPSPGR was preferred for both solid mass lesion and hemangioma. FSE was inferior to SE T2WI for lesion detection and conspicuity without statistical significance. CONCLUSIONS: For the evaluation of focal hepatic lesions, breath-hold FMPSPGR with and without contrast enhancement may replace the conventional SE T1WI. Because FSE was inferior to SE T2WI when the later is used with respiratory compensation in some cases, it is difficult to replace the SE T2WI with FSE. But FSE, FMPSPGR and Gd-FMPSPGR images, when combined, may replace SE T1WI and SE T2WI.