Autocalibrating CAIPIRINHA: Reformulating CAIPIRINHA as a 3D Problem

Kangrong Zhu¹, Adam Kerr¹, John M. Pauly¹

In CAIPIRINHA, multiple slices are excited simultaneously and are shifted with respect to each other in the phase encoding direction. This is fulfilled by applying a particular phase cycle to each excited slice through the phase encoding steps. A separate reference scan is usually needed to reconstruct the aliased slices. In this work, the reconstruction problem in CAIPIRINHA is reformulated as the reconstruction problem of an undersampled 3D Cartesian dataset by exploiting the DFT encoding nature of the multiband pulses used for excitation. The aliased slices were reconstructed using 2D GRAPPA with autocalibrating signal acquired at the k-space center.