98%
921
2 minutes
20
Background: Cardiac diffusion tensor imaging (cDTI) by cardiovascular magnetic resonance has the potential to assess microstructural changes through measures of fractional anisotropy (FA) and mean diffusivity (MD). However, normal variation in regional and transmural FA and MD is not well described.
Methods: Twenty normal subjects were scanned using an optimised cDTI sequence at 3T in systole. FA and MD were quantified in 3 transmural layers and 4 regional myocardial walls.
Results: FA was higher in the mesocardium (0.46 ±0.04) than the endocardium (0.40 ±0.04, p≤0.001) and epicardium (0.39 ±0.04, p≤0.001). On regional analysis, the FA in the septum was greater than the lateral wall (0.44 ±0.03 vs 0.40 ±0.05 p = 0.04). There was a transmural gradient in MD increasing towards the endocardium (epicardium 0.87 ±0.07 vs endocardium 0.91 ±0.08×10-3 mm2/s, p = 0.04). With the lateral wall (0.87 ± 0.08×10-3 mm2/s) as the reference, the MD was higher in the anterior wall (0.92 ±0.08×10-3 mm2/s, p = 0.016) and septum (0.92 ±0.07×10-3 mm2/s, p = 0.028). Transmurally the signal to noise ratio (SNR) was greatest in the mesocardium (14.5 ±2.5 vs endocardium 13.1 ±2.2, p<0.001; vs epicardium 12.0 ± 2.4, p<0.001) and regionally in the septum (16.0 ±3.4 vs lateral wall 11.5 ± 1.5, p<0.001). Transmural analysis suggested a relative reduction in the rate of change in helical angle (HA) within the mesocardium.
Conclusions: In vivo FA and MD measurements in normal human heart are heterogeneous, varying significantly transmurally and regionally. Contributors to this heterogeneity are many, complex and interactive, but include SNR, variations in cardiac microstructure, partial volume effects and strain. These data indicate that the potential clinical use of FA and MD would require measurement standardisation by myocardial region and layer, unless pathological changes substantially exceed the normal variation identified.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4503691 | PMC |
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132360 | PLOS |
JAMA Psychiatry
September 2025
School of Psychological Sciences, Monash University, Melbourne, Victoria, Australia.
Importance: Cannabis is the most commonly used illicit drug, with 10% to 30% of regular users developing cannabis use disorder (CUD), a condition linked to altered hippocampal integrity. Evidence suggests high-intensity interval training (HIIT) enhances hippocampal structure and function, with this form of physical exercise potentially mitigating CUD-related cognitive and mental health impairments.
Objective: To determine the impact of a 12-week HIIT intervention on hippocampal integrity (ie, structure, connectivity, biochemistry) compared with 12 weeks of strength and resistance (SR) training in CUD.
Brain Res Bull
September 2025
Department of Neurology, The Second Affiliated Hospital of Anhui Medical University, 230601, He Fei, China; Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health, 230032, Hefei, China; Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders, 230032, Hefei,
Background: The relationships between white matter microstructure, cortical atrophy, and cognitive function in cerebral small vessel disease (CSVD)-related white matter hyperintensities (WMHs) patients are unclear.
Methods: 71 right-handed WMHs patients (mild, n=23; moderate, n=27; severe, n=21) and 35 healthy controls were included. Tract-based spatial statistics (TBSS) assessed microstructure via fractional anisotropy (FA) and mean diffusivity (MD).
Exp Neurol
September 2025
CNRS UMR 5536 RMSB, University of Bordeaux, Bordeaux, France; Basic Science Department, Loma Linda University School of Medicine, Loma Linda, CA, USA; CNRS UMR 7372 CEBC, La Rochelle University, Villiers-en-Bois, France.
Introduction: The vulnerability of white matter (WM) in acute and chronic moderate-severe traumatic brain injury (TBI) has been established. In concussion syndromes, including preclinical rodent models, lacking are comprehensive longitudinal studies spanning the mouse lifespan. We previously reported early WM modifications using clinically relevant neuroimaging and histological measures in a model of juvenile concussion at one month post injury (mpi) who then exhibited cognitive deficits at 12mpi.
View Article and Find Full Text PDFFront Hum Neurosci
August 2025
Signal Processing Laboratory (LTS5), École Polytechnique Féderale de Lausanne (EPFL), Lausanne, Switzerland.
Introduction: Absence of language development is a condition encountered across a large range of neurodevelopmental disorders, including a significant proportion of children with autism spectrum disorder. The neurobiological underpinnings of non-verbal ASD (nvASD) remain poorly understood.
Methods: This study employed multimodal MRI to investigate white matter (WM) microstructural abnormalities in nvASD, focusing on language-related pathways.
Neurotrauma Rep
July 2025
Psychiatry and Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Most individuals with moderate-to-severe diffuse axonal injury (DAI) have impaired verbal fluency (VF) capacity. Still, the relationship between brain and VF recovery post-DAI has remained mostly unknown. The aim was to assess brain changes in 13 cortical thickness regions of interest (ROIs), fractional anisotropy (FA), and free water (FW) in three language-related tracts; the VF performance at 6 and 12 months after the DAI; and whether brain changes from 3 to 6 months predict VF performance from 6- to 12-month post-DAI.
View Article and Find Full Text PDF