SPIN LOCK AND MAGNETIZATION-TRANSFER MR-IMAGING OF FOCAL LIVER-LESIONS

The present study was designed to evaluate tissue contrast characteris tics obtained with the spin-lock (SL) technique by comparing the resul ts with those generated with a magnetization transfer(MT)-weighted gra dient echo [GRE, echo-time (TE) = 40 ms] sequence. Twenty-eight patien ts with hepatic hemangiomas (n = 14), or metastatic liver lesions (n = 14) were imaged at 0.1 T by using identical imaging parameters. Gradi ent echo, single-slice off-resonance MT, and multiple-slice SL sequenc es were obtained. SL and MT-effects were measured from the focal liver lesions and from normal liver parenchyma, In addition, tissue contras t values for the liver lesions were determined. Statistically signific ant difference between the SL-effects of the hemangiomas and metastase s, and also between the MT-effects of the lesions was observed (p < 0. 02), Tissue Contrast values for the lesions proved to be quite similar between the SI, and MT techniques, Our results indicate that at 0.1 T multiple-slice SL imaging provides MT based tissue contrast character istics in tissues rich in protein with good imaging efficiency and wid e anatomical coverage, and with reduced motion and susceptibility arti facts. (C) 1998 Elsevier Science Inc.