SIMULTANEOUS MULTISLICE ACQUISITION WITH ARTERIAL-FLOW TAGGING (SMART) USING ECHO-PLANAR IMAGING (EPI)

Arterial spin tagging techniques have been used to image tissue perfus ion in MR without contrast injection or ionizing radiation. Currently, spin tagging studies are performed primarily using single-slice imagi ng sequences, which are time consuming. This note reports a multislice echo-planar arterial spin tagging technique (Simultaneous Multislice Acquisition with aRterial-flow Tagging, or ''SMART''). Multiband RF en coding (Hadamard) is used to provide simultaneous multislice acquisiti on capability for spin tagging techniques (such as echo planar Imaging signal targeting with alternating radio frequency and flow-sensitive alternative inversion recovery). The method is illustrated with a two- slice pulse sequence that was implemented using the FAIR technique to generate two perfusion weighted images simultaneously. Compared with s ingle-slice sequences, this two-slice sequence provided similar image quality, signal-to-noise ratio, and twice the spatial coverage compare d with the single-slice technique:within the same scan time.