## 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 (σ) - 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.

Original language | English |
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Pages (from-to) | 664-669 |

Number of pages | 6 |

Journal | Magnetic resonance in medicine |

Volume | 50 |

Issue number | 4 |

DOIs | |

State | Published - Oct 1 2003 |

## Keywords

- CNS
- Diffusion
- MRI
- MRS
- Magnetic resonance