ArticleMagnetic resonance in medicine2013
Contrast and stability of the axon diameter index from microstructure imaging with diffusion MRI.
Article in Magnetic resonance in medicine, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 78 papers, 1 of them a synthesis that pooled it.
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78 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Considerations and recommendations from the ISMRM diffusion study group for preclinical diffusion MRI: Part 2-Ex vivo imaging: Added value and acquisition.Magnetic resonance in medicine · 2025Guideline
- Investigating the Sensitivity of the Diffusion MRI Signal to Magnetization Transfer and Permeability via Monte-Carlo Simulations.Magnetic resonance in medicine · 2026Article
- Axon Diameter Mapping in the Living Human Brain with Ultra-High-Gradient Diffusion MRI at 500 mT/m Gradient Strength.Human brain mapping · 2026Article
- Diffusion MRI experimental design optimization for microstructure imaging.Communications biology · 2026Article
- Validating the standard model of diffusion MRI in white matter with numerical substrates.Imaging neuroscience (Cambridge, Mass.) · 2026Article
- Article
- Considerations and recommendations from the ISMRM Diffusion Study Group for preclinical diffusion MRI: Part 3-Ex vivo imaging: Data processing, comparisons with microscopy, and tractography.Magnetic resonance in medicine · 2025Review
- Article
- Tutorial: a guide to diffusion MRI and structural connectomics.Nature protocols · 2025Review
- Axonal structure-function relationships across experimental modalities.Imaging neuroscience (Cambridge, Mass.) · 2025Article
- Feasibility of brain intra-axonal microstructure imaging with ultrahigh B-encoding using MAGNUS ultra-high-performance gradients.Imaging neuroscience (Cambridge, Mass.) · 2025Article
- Magnetic resonance imaging of postmortem human brain specimens: methodological considerations and prospects in psychoradiology.Psychoradiology · 2025Article
- Pore size estimation in axon-mimicking microfibers with diffusion-relaxation MRI.Magnetic resonance in medicine · 2024Article
- Pervasive alterations of intra-axonal volume and network organization in young children with a 16p11.2 deletion.Translational psychiatry · 2024Article
- Reconstructing the somatotopic organization of the corticospinal tract remains a challenge for modern tractography methods.Human brain mapping · 2023Article
- Widespread intra-axonal signal fraction abnormalities in bipolar disorder from multicompartment diffusion MRI: Sensitivity to diagnosis, association with clinical features and pharmacologic treatment.Human brain mapping · 2023Article
- A Method for In-Vivo Mapping of Axonal Diameter Distributions in the Human Brain Using Diffusion-Based Axonal Spectrum Imaging (AxSI).Neuroinformatics · 2023Article
- Novel insights into axon diameter and myelin content in late childhood and adolescence.Cerebral cortex (New York, N.Y. : 1991) · 2023Article
- Estimating axon radius using diffusion-relaxation MRI: calibrating a surface-based relaxation model with histology.Frontiers in neuroscience · 2023Article
- Improving MR cell size imaging by inclusion of transcytolemmal water exchange.NMR in biomedicine · 2022Article
18 more citing papers are in PubMed but not listed here.
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5 authors.
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Abstract
The ActiveAx technique fits the minimal model of white matter diffusion to diffusion MRI data acquired using optimized protocols that provide orientationally invariant indices of axon diameter and density. We investigated how limitations of the available maximal gradient strength (Gmax) on a scanner influence the sensitivity to a range of axon diameters. Multishell high-angular-diffusion-imaging (HARDI) protocols for Gmax of 60, 140, 200, and 300 mT/m were optimized for the pulsed-gradient-spin-echo (PGSE) sequence. Data were acquired on a fixed monkey brain and Monte-Carlo simulations supported the results. Increasing Gmax reduces within-voxel variation of the axon diameter index and improves contrast beyond what is achievable with higher signal-to-noise ratio. Simulations reveal an upper bound on the axon diameter (∼10 μm) that pulsed-gradient-spin-echo measurements are sensitive to, due to a trade-off between short T2 and the long diffusion time needed to probe larger axon diameters. A lower bound (∼2.5 μm) slightly dependent on Gmax was evident, below which axon diameters are identifiable as small, but impossible to differentiate. These results emphasize the key-role of Gmax for enhancing contrast between axon diameter distributions and are, therefore, relevant in general for microstructure imaging methods and highlight the need for increased Gmax on future commercial systems.
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