Fast conjugate phase image reconstruction based on a Chebyshev approximation to correct for B0 field inhomogeneity and concomitant gradients

Weitian Chen, Christopher T. Sica, Craig H. Meyer
2008 Magnetic Resonance in Medicine  
Off-resonance effects can cause image blurring or artifacts in a number of fast imaging methods. Concomitant gradient (Maxwell) fields [1] and B0 inhomogeneity, including main field inhomogeneity and susceptibility-induced field variations, are two common sources of off-resonance effects. When B0 inhomogeneity and concomitant gradients are both present, correction of only one of them is insufficient and sometimes can increase blurring artifacts in some parts of the image. Since both B0 field
more » ... omogeneity and concomitant gradients typically vary slowly in space, we could use conjugate phase reconstruction (CPR) [2] to correct them simultaneously. However, conjugate phase reconstruction is computationally prohibitive. In this abstract, we present a fast CPR method based on a Chebyshev approximation for simultaneous B0 inhomogeneity and concomitant gradient field correction. We apply the algorithm to off-resonance correction for spiral scanning. The method can be extended to other pulse sequences.
doi:10.1002/mrm.21703 pmid:18956462 pmcid:PMC3236685 fatcat:iuge76uibngklo2hc2drun6ryq