Maturation-dependent microstructure length scale in the corpus callosum of fixed rat brains by magnetic resonance diffusion-diffraction
Journal
Magnetic Resonance Imaging
Journal Volume
25
Journal Issue
1
Pages
78 - 86
Date Issued
2007
Author(s)
Abstract
Techniques capable of assessing microstructure length scale are potentially useful in probing the integrity of biologic tissue at the microscopic level. Although the magnetic resonance (MR) diffusion-diffraction technique has been proposed for years, its realization in an undissected brain has not been reported on. In this study, validation of this method in a phantom simulating a series of repeated sheets of water with regular spacing was first performed. The same technique was applied to the corpus callosum of fixed rat brains of different ages (range, 21-84 days). The phantom was constructed with a pile of transparencies immersed in water doped with Gd-DTPA. The measured signal showed diffraction-like coherence peaks, the modulation of which was influenced by the gap distance and the center-to-center distance of the adjacent gaps. The measured distances were consistent with the actual values. In five 84-day-old rats, the diffusion length scale derived from the diffractogram was highly reproducible. In the course of brain maturation, the measured size decreased with age. Electron microscopy showed that axons on day 21 were smaller in diameter and less myelinated as compared with those on day 84. Progressive decrease in the diffusion length scale observed during brain maturation might reflect a gradual decrease in transmembrane permeability due to myelination. In conclusion, MR diffusion-diffraction can be observed in the corpus callosum of fixed rat brains. This technique might be useful in probing the status of myelination in the development of disease. © 2007 Elsevier Inc. All rights reserved.
Subjects
Diffraction; Diffractograms; Diffusion; Microstructure; MRI
SDGs
Other Subjects
animal tissue; article; brain maturation; brain size; cellular parameters; controlled study; corpus callosum; diffraction; disease course; electron microscopy; magnetic resonance diffusion diffraction technique; male; membrane permeability; methodology; myelinated nerve; myelination; nerve fiber; nerve fiber growth; nonhuman; nuclear magnetic resonance; phantom; priority journal; radiological procedures; rat; reproducibility; signal detection; technique; validation process; Animals; Brain; Corpus Callosum; Magnetic Resonance Imaging; Male; Microscopy, Electron; Phantoms, Imaging; Rats; Rats, Wistar; Reproducibility of Results; Tissue Fixation; Rattus
Type
journal article