Initial experience with fast low-angle multiecho (FLAME) imaging of the central nervous system.

Abstract

Fast low-angle multiecho (FLAME) imaging uses partial flip angles of less than 90 degrees with 180 degrees radiofrequency refocusing pulses. The partial flip angle permits imaging with shorter repetition time (TR) values on the order of 750-1,000 ms for 30 degrees angles with image contrast characteristics identical to those obtained with conventional 90-180 degrees schemes and TRs on the order of 2,500 ms. The approximately threefold reduction in imaging time is accompanied by a decrease in signal-to-noise ratio. In many circumstances, however, this trade-off may produce entirely acceptable images of the CNS at a significant reduction in imaging time.