Exploring neurodegenerative disorders using advanced magnetic resonance imaging of the glymphatic system DOI Creative Commons
Jannik Prasuhn, Jiadi Xu, Jun Hua

et al.

Frontiers in Psychiatry, Journal Year: 2024, Volume and Issue: 15

Published: April 8, 2024

The glymphatic system, a macroscopic waste clearance system in the brain, is crucial for maintaining neural health. It facilitates exchange of cerebrospinal and interstitial fluid, aiding soluble proteins metabolites distributing essential nutrients signaling molecules. Emerging evidence suggests link between dysfunction pathogenesis neurodegenerative disorders, including Alzheimer's, Parkinson's, Huntington's disease. These disorders are characterized by accumulation propagation misfolded or mutant proteins, process which likely involved. Impaired could lead to buildup these toxic contributing neurodegeneration. Understanding system's role provide insights into their pathophysiology pave way new therapeutic strategies. Pharmacological enhancement reduce burden slow disease progression. Neuroimaging techniques, particularly MRI-based methods, have emerged as promising tools studying

Language: Английский

Age- and time-of-day dependence of glymphatic function in the human brain measured via two diffusion MRI methods DOI Creative Commons

Guangxu Han,

Ying Zhou,

Kemeng Zhang

et al.

Frontiers in Aging Neuroscience, Journal Year: 2023, Volume and Issue: 15

Published: May 22, 2023

Advanced age, accompanied by impaired glymphatic function, is a key risk factor for many neurodegenerative diseases. To study age-related differences in the human system, we measured influx and efflux activities of system via two non-invasive diffusion magnetic resonance imaging (MRI) methods, ultra-long echo time low-b tensor (DTIlow-b) measuring subarachnoid space (SAS) flow along middle cerebral artery DTI analysis perivascular (DTI-ALPS) medullary veins 22 healthy volunteers (aged 21-75 years). We first evaluated circadian rhythm dependence activity repeating MRI measurements at five points from 8:00 to 23:00 found no time-of-day awake state under current sensitivity measurements. Further test-retest demonstrated high repeatability both measurements, suggesting their reliability. Additionally, rate was significantly higher participants aged >45 years than 21-38, while lower those years. The mismatched might be due changes arterial pulsation aquaporin-4 polarization.

Language: Английский

Citations

27
Validating the accuracy of real-time phase-contrast MRI and quantifying the effects of free breathing on cerebrospinal fluid dynamics DOI Creative Commons
Pan Liu, K. P. Owashi,

Heimiri Monnier

et al.

Fluids and Barriers of the CNS, Journal Year: 2024, Volume and Issue: 21(1)

Published: March 7, 2024

Understanding of the cerebrospinal fluid (CSF) circulation is essential for physiological studies and clinical diagnosis. Real-time phase contrast sequences (RT-PC) can quantify beat-to-beat CSF flow signals. However, detailed effects free-breathing on parameters are not fully understood. This study aims to validate RT-PC's accuracy by comparing it with conventional phase-contrast sequence (CINE-PC) effect at intracranial extracranial levels using a time-domain multiparametric analysis method.

Language: Английский

Citations

13
Diffusion magnetic resonance imaging of cerebrospinal fluid dynamics: Current techniques and future advancements DOI
Adam M. Wright, Yu‐Chien Wu, Li Feng

et al.

NMR in Biomedicine, Journal Year: 2024, Volume and Issue: 37(9)

Published: May 7, 2024

Abstract Cerebrospinal fluid (CSF) plays a critical role in metabolic waste clearance from the brain, requiring its circulation throughout various brain pathways, including ventricular system, subarachnoid spaces, para‐arterial interstitial and para‐venous spaces. The complexity of CSF has posed challenge obtaining noninvasive measurements dynamics. assessment dynamics circulatory pathways is possible using diffusion magnetic resonance imaging (MRI) with optimized sensitivity to incoherent water movement across brain. This review presents an overview both established emerging MRI techniques designed measure their potential clinical applications. discussion offers insights into optimization acquisition parameters enhance specificity metrics on underlying Lastly, we emphasize importance cautious interpretations diffusion‐based imaging, especially when differentiating between tissue‐ fluid‐related changes or elucidating structural versus functional alterations.

Language: Английский

Citations

13
Higher intracranial arterial pulsatility is associated with presumed imaging markers of the glymphatic system: An explorative study DOI Creative Commons

Linyun Xie,

Yao Zhang, Hui Hong

et al.

NeuroImage, Journal Year: 2024, Volume and Issue: 288, P. 120524 - 120524

Published: Jan. 24, 2024

Arterial pulsation has been suggested as a key driver of paravascular cerebrospinal fluid flow, which is the foundation glymphatic clearance. However, whether intracranial arterial pulsatility associated with markers in humans not yet studied. Seventy-three community participants were enrolled study. 4D phase-contrast magnetic resonance imaging (MRI) was used to quantify hemodynamic parameters including flow index (PIflow) and area (PIarea) from 13 major intracerebral segments. Three presumed neuroimaging system measured: dilation perivascular space (PVS), diffusivity along (ALPS), volume fraction free water (FW) white matter. We explored relationships between PIarea, PIflow, markers, controlling for related covariates. PIflow internal carotid artery (ICA) C2 segment (OR, 1.05; 95% CI, 1.01-1.10, per 0.01 increase PI) C4 1.01-1.09) positively basal ganglia PVS, ICA 1.06, 1.02-1.10) correlated PVS ALPS basilar (β, -0.273, p, 0.046) PIarea -0.239, 0.041) C7 segments -0.238, 0.037). Intracranial system, but results consistent across different markers. Further studies are warranted confirm these findings.

Language: Английский

Citations

12
Perivascular brain clearance as a therapeutic target in cerebral amyloid angiopathy and Alzheimer's disease DOI Creative Commons
Orla Bonnar, Beth Eyre, Susanne J. van Veluw

et al.

Neurotherapeutics, Journal Year: 2025, Volume and Issue: unknown, P. e00535 - e00535

Published: Jan. 1, 2025

Language: Английский

Citations

2
Exploring Radial Asymmetry in MR Diffusion Tensor Imaging and Its Impact on the Interpretation of Glymphatic Mechanisms DOI Creative Commons
Adam M. Wright, Yu‐Chien Wu, Nan‐kuei Chen

et al.

Journal of Magnetic Resonance Imaging, Journal Year: 2023, Volume and Issue: 60(4), P. 1432 - 1441

Published: Dec. 29, 2023

Background Diffusion imaging holds great potential for the non‐invasive assessment of glymphatic system in humans. One technique, diffusion tensor along perivascular space (DTI‐ALPS), has introduced ALPS‐index, a novel metric evaluating diffusivity within space. However, it still needs to be established whether observed reduction ALPS‐index reflects axonal changes, common occurrence neurodegenerative diseases. Purpose To determine alterations can influence change ALPS‐index. Study Type Retrospective. Population 100 participants (78 cognitively normal and 22 with mild cognitive impairments) aged 50–90 years old. Field Strength/Sequence 3T; diffusion‐weighted single‐shot spin‐echo echo‐planar sequence, T1‐weighted images (MP‐RAGE). Assessment The ratio two radial diffusivities (i.e., λ2/λ3) across major white matter tracts distinct venous/perivenous anatomy that fulfill (ALPS‐tracts) do not (control tracts) anatomical assumptions were analyzed. Statistical Tests investigate correlation between λ2/λ3 age/cognitive function (RAVLT) while accounting effect age, linear regression was implemented remove age from each variable. Pearson analysis conducted on residuals obtained regression. significance set at p < 0.05. Results λ2 ~50% higher than λ3 demonstrated consistent pattern both ALPS control tracts. Additionally, advancing ( r = −0.39, −0.29, association forceps tract, respectively) decreased memory 0.24, 0.27, respectively). Data Conclusions results unveil widespread asymmetry changes aging neurodegeration. These findings highlight may solely reflect but also incorporate contributions. Level Evidence 3 Technical Efficacy Stage 2

Language: Английский

Citations

22
Dynamic diffusion-weighted imaging of intracranial cardiac impulse propagation along arteries to arterioles in the aging brain DOI Creative Commons
Qiuting Wen, Joseph Muskat,

Charles F. Babbs

et al.

Journal of Cerebral Blood Flow & Metabolism, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 13, 2025

Intracranial cardiac impulse propagation along penetrating arterioles is vital for both nutrient supply via blood circulation and waste clearance CSF circulation. However, current neuroimaging methods are limited to simultaneously detecting at pial arteries, arterioles, between them. We hypothesized that this could be detected paravascular dynamics it may change with aging. Using dynamic diffusion-weighted imaging (dynDWI), we oscillatory motion synchronized the finger photoplethysmography in subarachnoid space (SAS) cerebral cortex, a delay revealing an pathway from SAS averaging 84 milliseconds. Data 70 subjects aged 18 85 years showed bimodal age-related SAS-Cortex travel time: initially increases age, peaks around 45 years, then decreases. Computational biomechanical modeling of cardiovascular system was performed replicated 84-millisecond delay. Sensitivity analysis suggests variations time primarily driven by changes arteriolar compliance. These findings support use dynDWI measuring intracranial highlight its potential assessing related vascular functions.

Language: Английский

Citations

1
Altered Clearance in Alzheimer's Disease and Cerebral Amyloid Angiopathy DOI
Soheil Mohammadi, Mahsa Dolatshahi,

Farzaneh Rahmani

et al.

Neuroimaging Clinics of North America, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 1, 2025

Language: Английский

Citations

1
PET Imaging of Neurofluids DOI
Liangdong Zhou, Yi Li, Mony J. de Leon

et al.

Neuroimaging Clinics of North America, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 1, 2025

Language: Английский

Citations

1
The pulsing brain: state of the art and an interdisciplinary perspective DOI Creative Commons
Andrea Lecchini‐Visintini, Jaco J.M. Zwanenburg, Qiuting Wen

et al.

Interface Focus, Journal Year: 2025, Volume and Issue: 15(1)

Published: April 4, 2025

Understanding the pulsing dynamics of tissue and fluids in intracranial environment is an evolving research theme aimed at gaining new insights into brain physiology disease progression. This article provides overview related magnetic resonance imaging, ultrasound medical diagnostics mathematical modelling biological tissues fluids. It highlights recent developments, illustrates current goals emphasizes importance collaboration between these fields.

Language: Английский

Citations

1