Understanding diffusion-weighted MR signal in brain white matter (WM) has been a long-sought-after goal. Modern research pursues this goal by focusing on the biological compartments that contributes essentially to the signal. In this study, we experimentally address the apparent presence of a compartment in which water motion is restricted in all spatial directions. Using isotropic diffusion encoding, we establish an upper bound on the fraction of such a compartment, which is shown to be about 2% of the unweighted signal for moderate diffusion times. This helps to eliminate such a compartment that have been assumed in literature on biophysical modeling. We also used the diffusion decay curve obtained from the isotropic encoding to establish a lower limit on the mean diffusivities of either of intra- or extra-axonal compartment as a function of their relative water fraction.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.neuroimage.2017.10.051 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
From circuits to lifespan: translating mouse and human timelines with neuroimaging based tractography.
J Neurosci
January 2025
Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA.
Animal models are commonly used to investigate developmental processes and disease risk, but humans and model systems (e.g., mice) differ substantially in the pace of development and aging.
View Article and Find Full Text PDFVolumetric response after closure of a spinal CSF leak in patients with spontaneous intracranial hypotension: a multicompartmental longitudinal study.
J Neurointerv Surg
January 2025
Department of Neuroradiology, Medical Center - University of Freiburg, Freiburg, Germany
Background: Cerebrospinal fluid (CSF) loss in spontaneous intracranial hypotension (SIH) is accompanied by volume shifts between the intracranial compartments. This study investigated tricompartimental and longitudinal volume shifts after closure of a CSF leak.
Methods: Patients with SIH and suitable pre-therapeutic and post-therapeutic imaging for volumetric analysis were identified from our tertiary care center between 2020 and 2023.
Post-infectious acute cerebellar ataxia in a young adult.
BMJ Case Rep
January 2025
Institute of Neurological Sciences, Prince of Wales Hospital and the University of New South Wales, Randwick, Sydney, New South Wales, Australia
Acute cerebellar ataxia is a clinical syndrome that involves loss of balance and coordination, typically within less than 72 hours. It usually presents in children and rarely affect adults. A woman in her early 20s presented with acute onset dizziness, vertigo, truncal ataxia and dysarthria 2 weeks following an acute viral illness.
View Article and Find Full Text PDFA High Fat, High Sugar Diet Exacerbates Persistent Post-Surgical Pain and Modifies the Brain-Microbiota-Gut Axis in Adolescent Rats.
Neuroimage
January 2025
Department of Neuroscience, Monash University, Melbourne, VIC, Australia; Gastroenterology, Immunology, Neuroscience (GIN) Discovery Program. Electronic address:
Persistent post-surgical pain (PPSP) occurs in a proportion of patients following surgical interventions. Research suggests that specific microbiome components are important for brain development and function, with recent studies demonstrating that chronic pain results in changes to the microbiome. Consumption of a high fat, high sugar (HFHS) diet can drastically alter composition of the microbiome and is a modifiable risk factor for many neuroinflammatory conditions.
View Article and Find Full Text PDFTractGraphFormer: Anatomically informed hybrid graph CNN-transformer network for interpretable sex and age prediction from diffusion MRI tractography.
Med Image Anal
January 2025
Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. Electronic address:
The relationship between brain connections and non-imaging phenotypes is increasingly studied using deep neural networks. However, the local and global properties of the brain's white matter networks are often overlooked in convolutional network design. We introduce TractGraphFormer, a hybrid Graph CNN-Transformer deep learning framework tailored for diffusion MRI tractography.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!