Diffusion MRI microstructural models in the cervical spinal cord – Application, normative values, and correlations with histological analysis

In this study, we apply a diffusion “signal” model (diffusion tensor imaging, DTI) and two commonly implemented “microstructural” models (neurite orientation dispersion and density imaging, NODDI; spherical mean technique, SMT) in the human cervical spinal cord of twenty-one healthy controls. We first provide normative values of DTI, SMT, and NODDI indices in a number of white matter ascending and descending pathways, as well as various gray matter regions. We then aim to validate the sensitivity and specificity of these diffusion-derived contrasts by relating these measures to indices of the tissue microenvironment provided by a histological template. We find that DTI indices are sensitive to a number of microstructural features, but lack specificity. The microstructural models also show sensitivity to a number of microstructure features; however, they do not capture the specific microstructural features explicitly modelled. Although often regarded as a simple extension of the brain in the central nervous system, it may be necessary to re-envision, or specifically adapt, diffusion microstructural models for application to the human spinal cord with clinically feasible acquisitions – specifically, adjusting, adapting, and re-validating the modeling as it relates to both theory (i.e. relevant biology, assumptions, and signal regimes) and parameter estimation (for example challenges of acquisition, artifacts, and processing).
Source: NeuroImage - Category: Neuroscience Source Type: research

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Source: EJNMMI Research - Category: Radiology Source Type: research
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Source: Medgadget - Category: Medical Devices Authors: Tags: Neurology Pediatrics Psychiatry Radiology Rehab Source Type: blogs
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Source: World Journal of Urology - Category: Urology & Nephrology Source Type: research
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Source: European Spine Journal - Category: Orthopaedics Source Type: research
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Source: Journal of Knee Surgery - Category: Orthopaedics Authors: Tags: Original Article Source Type: research
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Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research
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