High Resolution PROPELLER EPI with Reversed Phase Encoding Distortion Correction

Irvin Teh¹

Single-shot echo planar imaging (EPI) is widely used in MRI, but is resolution-limited and suffers from geometric distortions. Periodically Rotated Overlapping ParalEL Lines with Enhanced Reconstruction (PROPELLER) allows for higher resolution EPI by acquiring data in multiple shots. However, distortions in individual PROPELLER blades lead to artifacts in the final image. These distortions can be addressed by employing the reversed phase encoding gradient method to first correct for distortions between individual blade pairs. The corrected blades can be combined to enable high-resolution EPI with minimal distortions for applications such as structural and diffusion-weighted imaging.