CHEMICAL-SHIFT ARTIFACT-FREE IMAGING - A NEW OPTION IN MRI

A high-speed proton spectroscopic imaging method with high spatial res olution was used for obtaining water, fat, and chemical shift artifact -free images on a 1.5 T MR scanner. The technique is based on a fast r adiofrequency (RF) spoiled gradient-echo sequence. The chemical shift information is encoded by incrementing the echo time in a series of im age records, Suppression of water or fat signals is not used. The tech nique does not require a highly homogeneous magnetic held, Spectroscop ic images of a human volunteer were compared with corresponding conven tional images obtained using the short inversion time inversion recove ry (STIR) and the selective partial inversion recovery (SPIR) methods. The results demonstrate that it is possible to produce images entirel y free from chemical shift artifacts using only a few chemical shift e ncoding steps. The technique also produces pure water and fat images w hich are significantly better than those produced by using the convent ional methods STIR and selective partial inversion recovery. The descr ibed method appears to be promising for routine clinical applications because it can be fully automated. (C) 1998 Elsevier Science Inc.