Hybrid-space reconstruction for simultaneous multi-slab DWI with blipped-CAIPI

3D simultaneous multi-slab imaging (SMSlab) can achieve high-resolution DWI with high SNR efficiency. Multi-band acceleration can also achieve less SNR reduction. Recently, we integrated SMSlab DWI with blipped-CAIPI gradients to reduce the g-factor penalty and proposed a 4D k-space framework (kx-ky-kz-km) to model the signal encoding, with km representing the multi-band encoding. Because the blipped-CAIPI gradients are applied along the slice direction, they introduce kz deviations from the nominal k-space location. This study proposed a hybrid-space reconstruction algorithm, REACH, to solve the phase interferences introduced by the blipped-CAIPI gradients.