Echo-planar imaging of the liver with a standard MR imaging system.

Abstract

A multisection, whole-body echo-planar imaging (EPI) sequence was developed to obtain T2-weighted images of the liver in one 18-second breath hold with a standard magnetic resonance (MR) imaging system. This capability was achieved by dividing the data acquisition period into eight interleaved segments rather than one or two as implemented previously with EPI systems having high-power gradient subsystems. The interleaved echo-planar images had excellent depiction of anatomy and no identifiable respiratory artifact. In 26 lesions in 12 patients, the eight-shot echo-planar images (2,000/66 [repetition time msec/echo time msec]) had superior contrast compared with conventional T2-weighted spin-echo (SE) images (2,500/60) by an average factor of 1.22 +/- 0.31 (standard deviation) and an average contrast-to-noise ratio relative to conventional T2-weighted SE images of 0.85 +/- 0.22. With a conventional MR imaging system, breath-hold T2-weighted echo-planar images of the liver are comparable in diagnostic quality to conventional T2-weighted SE images.