Gradient-echo MR imaging: techniques and acronyms.

This overview briefly traces the history and nomenclature of gradient-recalled-echo (GRE) techniques used in magnetic resonance (MR) imaging. GRE sequences, which are now offered commercially by 11 major manufacturers of MR imagers, are presented to illustrate their structural similarities and subtle differences in implementation. A classification scheme is proposed for these sequences employing a vendor-independent nomenclature. A glossary of GRE abbreviations and acronyms found in the current MR marketplace also is presented.