Systematic noise compensation for simultaneous multislice acquisition using rosette trajectories (SMART)

Simultaneous multislice acquisition using rosette trajectories (SMART) is a recently introduced functional magnetic resonance imaging pulse sequence that offers high‐speed data acquisition by simultaneously exciting several slices. A drawback to its benefit of rapid acquisition is the cumulative effect of the systematic noise present in the off‐resonant slices. In this work, a systematic noise compensation method is implemented to gauge the performance of the multislice SMART method versus a single‐slice rosette method in a motor activation study. The normalized standard deviation of the noise‐compensated image timecourse is reduced by 25% (single‐slice rosette) and 62% (SMART), and the normalized volume of motor activation is increased by 25% (single‐slice rosette) and 44% (SMART). The noise‐compensated SMART method has an average timecourse standard deviation only 9% higher than the noise‐compensated single‐slice rosette method, while increasing the acquisition rate threefold. Magn Reson Med 41:1073–1076, 1999. © 1999 Wiley‐Liss, Inc.