Iterative estimation of T2 to correct echo planar magnetic resonance images

摘要

An iterative algorithm has been developed to correct for distortions in echo planar images caused by short T2 components. The values of T2 are initially estimated from a set of images produced by the inverse Fourier-transform of the geometric mean of Hermitian symmetric points. The estimated T2 values are then used to compute k-space data, which when compared with the true data, provide error data sets and corresponding images to iteratively refine the estimates of T2. Images corrected for T2 decay are thereby generated at specified echo times. Computer simulation studies of several phantoms show good convergence under a variety of conditions. This procedure should enable wider data acquisition windows to be utilized in echo planar or spin echo images, leading to better resolution or better signal-to-noise ratio.