Parallel imaging acceleration of EPIK for reduced image distortions in fMRI

EPI with Keyhole (EPIK) is a hybrid imaging technique used to improve the performance of EPI in dynamic MRI applications. The method had been previously validated at 1.5T with both phantom and in vivo images; EPIK was able to provide a higher temporal resolution and less image distortions than single-shot EPI. The data presented here demonstrate that the performance of EPIK can be further improved by accelerating it with the parallel imaging. For this work, this combination was tested at 3T. After initial evaluation using phantom images, use of the method in functional MRI was verified with visual fMRI measurements as well as MRI simulation results. The results showed that accelerated EPIK had increased temporal resolution with favorable robustness against susceptibility artifacts when compared with EPI or non-accelerated EPIK. ► Accelerated EPIK, an imaging method for dynamic MRI has been demonstrated at 3T. ► Accelerated EPIK offered a higher imaging speed and less image distortions than EPI. ► Visual fMRI results from accelerated EPIK showed high similarity with those from EPI. ► The use of accelerated EPIK in fMRI was also verified with an MRI simulator, JEMRIS.