New Imaging Strategies Using a Motion-Resistant Liver Sequence in Uncooperative Patients
Figure 6
Concept of the under-sampling pattern of the CAIPIRINHA technique. The lattice work represents k-space. The black dots indicate the sampling positions, and the empty cells imply omitted sampling. (a) In the 1D parallel acquisition technique for a given total acceleration factor of 2, the under-sampling pattern can occur only in the phase-encoding direction. (b) In the 2D standard parallel acquisition technique without delta shift for a given total acceleration factor 4 (2 × 2), the under-sampling pattern can be generated concurrently in the phase- and partition-encoding directions. (c) In the 2D CAIPIRINHA technique with a delta shift of 1 for a given total acceleration factor 4 (2 × 2), data sampling is acquired by shifting every other filled partition-encoding line by as much as 1 in the partition-encoding direction. By shifting the sampling positions in a well-directed manner, aliasing can be shifted and reduced.
