Abstract
AbstractThe feasibility of non-invasive axonal diameter quantification with diffusion MRI is a strongly debated topic due to the neuroscientific potential of such information and its relevance for the axonal signal transmission speed. It has been shown that under ideal conditions, the minimal diameter producing detectable signal decay is bigger than most human axons in the brain, even using the strongest currently available MRI systems. We show that resolving the simplest situations including multiple diameters is unfeasible even with diameters much bigger than the diameter limit. Additionally, the recently proposed effective diameter resulting from fitting a single value over a distribution is almost exclusively influenced by the biggest axons. We show how impractical this metric is for comparing different distributions. Overall, axon diameters currently cannot be quantified by diffusion MRI in any relevant way.
Publisher
Cold Spring Harbor Laboratory
Reference55 articles.
1. Fiber composition of the human corpus callosum
2. A general framework for experiment design in diffusion MRI and its application in measuring direct tissue-microstructure features
3. Orientationally invariant indices of axon diameter and density from diffusion MRI
4. Ashtarayeh, M. , Streubel, T. , Periquito, J. , Pohlmann, A. , Nien-dorf, T. , Kirilina, E. , Morawski, M. , Jäger, C. , Geyer, S. , Barakovic, M. , Daducci, A. , and Mohammadi, S. Axon diameter estimation in fixed human optic chiasm using diffusion weighted MR microscopy and microstructure-informed tractography. In Proceedings of the 27th Annual Meeting of the ISMRM (2019).
5. The CONNECT project: Combining macro- and micro-structure
Cited by
10 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献