Title :
Reconstruction of MRI signal losses in EPI images
Author_Institution :
Nat. Inst. of Inf. & Commun. Technol., Kobe
Abstract :
This paper derives and implements a method for recovering MRI signal losses caused by susceptibility-induced magnetic field gradients (SFGs) in regions with large static field inhomogeneities in echo-planar imaging (EPI). Factor to account for SFGs was added in a traditional EPI equation, which was a simple Fourier transform (FT) for expressing the actual k-space data of an EPI scan. The inverse calculation of this "distorted EPI" equation was used as a kernel to correct reduction in intensity during reconstruction. A step-by-step EPI reconstruction method is proposed to avoid complicated phase unwrapping problems
Keywords :
Fourier transforms; biomedical MRI; image reconstruction; medical image processing; EPI images; Fourier transform; MRI signal losses; MRI signal recovery; distorted EPI equation; echo-planar imaging; image reconstruction; inverse calculation; k-space data; large static field inhomogeneities; susceptibility-induced magnetic field gradients; Communications technology; Equations; Fourier transforms; Image reconstruction; Kernel; Magnetic fields; Magnetic resonance imaging; Magnetic susceptibility; Predistortion; Reconstruction algorithms;
Conference_Titel :
Engineering in Medicine and Biology Society, 2005. IEEE-EMBS 2005. 27th Annual International Conference of the
Conference_Location :
Shanghai
Print_ISBN :
0-7803-8741-4
DOI :
10.1109/IEMBS.2005.1616673
