Dataset Information

In vivo mapping of human spinal cord microstructure at 300mT/m.

ABSTRACT: The ability to characterize white matter microstructure non-invasively has important applications for the diagnosis and follow-up of several neurological diseases. There exists a family of diffusion MRI techniques, such as AxCaliber, that provide indices of axon microstructure, such as axon diameter and density. However, to obtain accurate measurements of axons with small diameters (<5?m), these techniques require strong gradients, i.e. an order of magnitude higher than the 40-80mT/m currently available in clinical systems. In this study we acquired AxCaliber diffusion data at a variety of different q-values and diffusion times in the spinal cord of five healthy subjects using a 300mT/m whole body gradient system. Acquisition and processing were optimized using state-of-the-art methods (e.g., 64-channel coil, template-based analysis). Results consistently show an average axon diameter of 4.5+/-1.1?m in the spinal cord white matter. Diameters ranged from 3.0?m (gracilis) to 5.9?m (spinocerebellar tracts). Values were similar across laterality (left-right), but statistically different across spinal cord pathways (p<10(-5)). The observed trends are similar to those observed in animal histology. This study shows, for the first time, in vivo mapping of axon diameter in the spinal cord at 300mT/m, thus creating opportunities for applications in spinal cord diseases.

SUBMITTER: Duval T

PROVIDER: S-EPMC4562035 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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In vivo mapping of human spinal cord microstructure at 300mT/m.

Duval Tanguy T McNab Jennifer A JA Setsompop Kawin K Witzel Thomas T Schneider Torben T Huang Susie Yi SY Keil Boris B Klawiter Eric C EC Wald Lawrence L LL Cohen-Adad Julien J

NeuroImage 20150619

The ability to characterize white matter microstructure non-invasively has important applications for the diagnosis and follow-up of several neurological diseases. There exists a family of diffusion MRI techniques, such as AxCaliber, that provide indices of axon microstructure, such as axon diameter and density. However, to obtain accurate measurements of axons with small diameters (<5μm), these techniques require strong gradients, i.e. an order of magnitude higher than the 40-80mT/m currently a ...[more]

PMID: 26095093

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Dataset Information

In vivo mapping of human spinal cord microstructure at 300mT/m.

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In vivo mapping of human spinal cord microstructure at 300mT/m.

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