Error model for reduction of cardiac and respiratory motion effects in quantitative liver DW-MRI.
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ABSTRACT:
SUBMITTER: Murphy P
PROVIDER: S-EPMC4142067 | biostudies-literature | 2013 Nov
REPOSITORIES: biostudies-literature
Publications
Error model for reduction of cardiac and respiratory motion effects in quantitative liver DW-MRI.
Murphy Paul P Wolfson Tanya T Gamst Anthony A Sirlin Claude C Bydder Mark M
Magnetic resonance in medicine 20121227 5
Diffusion-weighted images of the liver exhibit signal dropout from cardiac and respiratory motion, particularly in the left lobe. These artifacts cause bias and variance in derived parameters that quantify intravoxel incoherent motion. Many models of diffusion have been proposed, but few separate attenuation from diffusion or perfusion from that of bulk motion. The error model proposed here (Beta*LogNormal) is intended to accomplish that separation by modeling stochastic attenuation from bulk mo ...[more]
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