T2-weighted MR imaging of focal hepatic lesions: comparison of various RARE and fat-suppressed spin-echo sequences.

The authors prospectively compared four T2-weighted magnetic resonance (MR) sequences, including high-resolution 512 x 512 (matrix size) RARE (rapid acquisition with relaxation enhancement), 256 x 256 RARE, 128 x 256 breath-hold RARE, and 192 x 256 fat-suppressed spin-echo (T2FS) sequences, in the evaluation of 16 patients with focal hepatic masses. MR images were evaluated by quantitative lesion-liver signal difference-to-noise ratios (SDNRs) and subjective evaluation of image artifact and image quality. No significant differences were observed between RARE sequences in SDNR values. The T2FS sequence had a significantly higher SDNR than the 512 x 512 RARE sequence (24.6 +/- 15.0 vs 14.5 +/- 9.7) (P = .008). Image quality was rated highest for the 512 x 512 RARE and T2FS sequences (P = .006). The inherent advantage of high spatial resolution suggests that the 512 x 512 RARE sequence may be of value in detecting hepatic lesions.