Simultaneous Multi-slice Acquisition Using A Parallel MR Imaging System

In this study, we attempt to reduce the Magnetic Resonance Imaging (MRI) scan time by combining SImultaneous Multi-slice Acquisition (SIMA) and blind source separation method in a phased array MR acquisition system[1-6]. Imaging was first acquired by a typical parallel imaging MR with multi-slice excitation RF profile; this will ends up with an overlapped image. By using blind source separation method which is addressed by Larkman [7] with information of these coil sensitivity distribution, one can further achieve n multiple slice images. The overall reduction ratio in acquisition time then will be the traditional reduction ratio R times this slice number n. By increasing the acceleration factor of Parallel Imaging, the SNR which involves ill-condition problem dropped severely and induce the obvious noise amplification in this reconstruction process [8-10]. Tikhonov regularization is then employed to treat this ill-condition problem. In the preliminary study, we have successfully implement this technology by exciting two slices simultaneously in addition to the reduction factor R = 2 for a parallel MR system in in vivo experiment. In the conference, we will show results with higher number of slice number n for high spatiotemporal resolution on MR imaging system. In the future, more excited slices will be applied to this technique and the dynamic functional studies will also be used to test its capability.