Dual-polarity SENSE with calibration refinement enables robust Nyquist ghost correction on a high-performance gradient system

Motivation: Echo-planar imaging (EPI) is prone to Nyquist ghosts, which are exacerbated on scanners with high-performance gradients. While dual-polarity GRAPPA (DPG) helps alleviate these artifacts, it does not permit regularized multi-shot reconstruction. Goal(s): To introduce a SENSE-based method to address Nyquist ghosts on high-performance gradient systems and to lend itself to regularized multi-shot reconstruction. Approach: We propose dual-polarity SENSE (DPS) for ghost correction where phase differences between even and odd lines are captured in ESPIRiT coil sensitivity estimates based on a tailored calibration scan. Results: DPS effectively reduces Nyquist ghost artifacts in phantom and in vivo data on high-performance gradient systems. Impact: We provide a robust SENSE-based Nyquist correction method that can be integrated with advanced multi-shot EPI reconstruction techniques and can address challenging Nyquist ghosts on high-performance gradient systems.