NeuroImage, Journal Year: 2024, Volume and Issue: 305, P. 120988 - 120988
Published: Dec. 25, 2024
Language: Английский
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
26
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
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
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
11
Neurotherapeutics, Journal Year: 2025, Volume and Issue: unknown, P. e00535 - e00535
Published: Jan. 1, 2025
Language: Английский
Citations
2
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
21
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
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
Neurobiology of Disease, Journal Year: 2023, Volume and Issue: 177, P. 105986 - 105986
Published: Jan. 2, 2023
Recent human and animal model experimental studies revealed novel pathways for fluid movement, immune cell trafficking metabolic waste clearance in CNS. These raise the intriguing possibility that newly discovered pathways, including glymphatic system, lymphatic meningeal vessels skull-brain communication channels, are impaired aging neurovascular neurodegenerative diseases associated with dementia, Alzheimer's disease (AD) AD-related dementia. We provide an overview of dural systems, review current methods approaches used to study flow humans animals, discuss evidence controversies related its role CNS homeostasis under physiological pathophysiological conditions. Non-invasive imaging needed fully understand mechanisms driving movement their roles across lifespan healthy aging-related
Language: Английский
Citations
14
NMR in Biomedicine, Journal Year: 2024, Volume and Issue: 37(8)
Published: March 11, 2024
The glymphatic system is a of specialized perivascular spaces in the brain that facilitates removal toxic waste solutes from brain. Evaluation function by means magnetic resonance imaging (MRI) has thus far been largely focused on rodents because limitations intrathecal delivery gadolinium-based contrast agents to humans. This review discusses MRI methods can be employed clinically for glymphatic-related measurements intended early diagnosis, prevention, and treatment various neurological conditions. Although system-based research its stages, recent studies have identified promising noninvasive markers associated with alterations diseases. However, further optimization data acquisition, validation, modeling are needed investigate within clinical setting.
Language: Английский
Citations
5