Detection of microscopic anisotropy in gray matter and in a novel tissue phantom using double Pulsed Gradient Spin Echo MR

J Magn Reson. 2007 Nov;189(1):38-45. doi: 10.1016/j.jmr.2007.07.003. Epub 2007 Jul 18.

Abstract

A double Pulsed Gradient Spin Echo (d-PGSE) MR experiment was used to measure and assess the degree of local diffusion anisotropy in brain gray matter, and in a novel "gray matter" phantom that consists of randomly oriented tubes filled with water. In both samples, isotropic diffusion was observed at a macroscopic scale while anisotropic diffusion was observed at a microscopic scale, however, the nature of the resulting echo attenuation profiles were qualitatively different. Gray matter, which contains multiple cell types and fibers, exhibits a more complicated echo attenuation profile than the phantom. Since microscopic anisotropy was observed in both samples in the low q regime comparable to that achievable in clinical scanner, it may offer a new potential contrast mechanism for characterizing gray matter microstructure in medical and biological applications.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Algorithms
  • Animals
  • Anisotropy
  • Brain / metabolism*
  • Brain / pathology*
  • Central Nervous System
  • Computer Simulation
  • Echo-Planar Imaging
  • Macaca mulatta
  • Magnetic Resonance Imaging / instrumentation
  • Magnetic Resonance Imaging / methods*
  • Phantoms, Imaging