UIC-2011-136 – Time-Efficient Phase Error Correction in EPI-PROPELLER

Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction (PROPELLER) MRI is a widely used method to correct for patient motion. Although echo planar imaging (EPI) based PROPELLER is a more robust technique compared to fast spin echo (FSE) based PROPELLER, EPI-PROPELLER suffers from Nyquist ghosts which necessitates phase correction. Phase correction can be implemented through the use of reference scans, specifically acquired for and applied to each PROPELLER blade, however, this approach doubles the total scan time and cannot correct for “oblique phase errors” arising from gradient anisotropy. UIC researchers have developed a time-efficient method, which only requires two or three reference scans—independent to the total number of PROPELLER blades acquired—to correct for constant, linear, and phase errors in EPI-based pulse sequences. They have demonstrated the effectiveness of this method in both the orthogonal and oblique planes for short-axis PROPELLER-EPI (SAP-EPI) and long-axis PROPELLER (LAP-EPI) images. Proof of concept has been demonstrated in both phantom and human experiments. Jonathan Gortat jgortat@otm.uic.edu (312) 413-1643