Differentiation of hepatic malignancies from hemangiomas and cysts by T2 relaxation times: Early experience with multiply refocused four-echo imagingat 1.5 T

The purpose of this study was to examine hepatic lesions with a sequence de signed to yield improved T2 measurements and evaluate the clinical utility of these measurements in distinguishing malignant from benign disease. Usin g a modified Carr-Purcell sequence incorporating features designed to compe nsate for imperfections in the imaging system, including a train of refocus ing pulses emitted in an MLEV pattern oriented in composite fashion along a ll three coordinate axes, and a single spatially selective pulse placed imm ediately before a spiral readout, 14 benign lesions and 13 malignant lesion s were evaluated prospectively with a conventional 1.5 T imager, The maximu m, minimum, and mean T2 values of malignant lesions, hemangiomas, and cysts exceeded corresponding published values from spin-echo and echoplanar stud ies, The mean T2 value of the malignant lesions differed significantly (P < 0.0001) from those of hemangiomas and cysts. All malignant lesions and all benign lesions were distinguishable by their T2 values, which had ranges o f no greater than 118.6 msec and no less than 134.3 msec, respectively. Thi s early experience suggests that improved T2 measurements can facilitate th e differentiation of hepatic malignancies from hemangiomas and cysts. J, Ma gn, Reson, Imaging 1999;9:81-86, (C) 1999 Wiley-Liss, Inc.