Auto-Calibrated Dynamic Parallel MRI with Phase-Sensitive Data

A number of MRI applications rely on dynamic phase information embedded in the acquired images. Such applications often require multiple acquisitions, leading to possibly long scan time and low temporal resolution. Previously, SENSE method has been used for phase-sensitive data to shorten acquisition time. However, SENSE can be subject to artifacts due to inaccurate coil sensitivities and low SNR. In this paper, dynamic phase data are derived from self-calibrated parallel MRI and an optimal method is used to combine phase information from multiple receiver channels. Simulation results using 4-channel prostate imaging data show that it is possible to get a factor of 3 speedup and the new method is more accurate than the SENSE method in reconstructing the phase information, thus has potential to improve phase-sensitive MRI applications such as phase contrast velocity mapping, temperature mapping for thermal therapy, and Dixon water/fat imaging