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Statistical model for diffusion attenuated MR signal.

Dmitriy A Yablonskiy·G Larry Bretthorst·Joseph J H Ackerman
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Abstract

A general statistical model that can describe a rather large number of experimental results related to the structure of the diffusion-attenuated MR signal in biological systems is introduced. The theoretical framework relies on a phenomenological model that introduces a distribution function for tissue apparent diffusion coefficients (ADC). It is shown that at least two parameters--the position of distribution maxima (ADC) and the distribution width (sigma)--are needed to describe the MR signal in most regions of a human brain. A substantial distribution width, on the order of 36% of the ADC, was found for practically all brain regions examined. This method of modeling the MR diffusion measurement allows determination of an intrinsic tissue-specific ADC for a given diffusion time independent of the strength of diffusion sensitizing gradients. The model accounts for the previously found biexponential behavior of the diffusion-attenuated MR signal in CNS.

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BrainDiffusion Magnetic Resonance ImagingHumansModels, StatisticalJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Dmitriy A Yablonskiy, G Larry Bretthorst, Joseph J H Ackerman. 2003. Statistical model for diffusion attenuated MR signal.. https://doi.org/10.1002/mrm.10578

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