Robust field map generation using a triple-echo acquisition

摘要: Purpose To establish a fast and robust technique for generating magnetic field maps the correction of geometric distortions in echo-planar resonance (MR) images. Materials Methods Multislice gradient-echo (GE) images were acquired at echo times 6, 6.5, 7.5 msec order to cover shift range ±666 Hz resulting B0 maps. To account possible phase wrap scenarios, seven triples calculated each pixel. Linear regression vs. time was performed set. The slope set with minimum fitting error taken as true respective pixel. Results Based on distribution, is shown be feasible effective assessing distribution brain 3 T, especially inferior areas (amygdalae, hippocampus). Examples distortion corrected using are shown. Conclusion The approach presented yields estimation requires under minute additional acquisition only seconds computational time. As such, it easily apply image routine functional MR imaging (fMRI) studies, enabling improved coregistration activation structures anatomical images. J. Magn. Reson. Imaging 2004;20:730–734. © 2004 Wiley-Liss, Inc.