Reproducibility of diffusion tensor image analysis along the perivascular space (DTI-ALPS) for evaluating interstitial fluid diffusivity and glymphatic function: CHanges in Alps index on Multiple conditiON acquIsition eXperiment (CHAMONIX) study

Japanese Journal of Radiology, Journal Year: 2021, Volume and Issue: 40(2), P. 147 - 158

Published: Aug. 14, 2021

The diffusion tensor image analysis along the perivascular space (DTI-ALPS) method was developed to evaluate brain's glymphatic function or interstitial fluid dynamics. This study aimed reproducibility of DTI-ALPS and effect modifications in imaging data evaluation.Seven healthy volunteers were enrolled this study. Image acquisition performed for test-retest using a fixed sequence modified methods which included placement region interest (ROI), plane, head position, averaging, number motion-proving gradients, echo time (TE), different scanner. ALPS-index values evaluated change conditions listed above.This by showed very high (intraclass coefficient = 0.828) value. bilateral ROI higher reproducibility. averaging difference scanner did not influence values. However, modification plane position impaired reproducibility, gradients affected from 12-axis DTI 3-axis diffusion-weighted (DWI) good correlation (r 0.86). Also, shorter TE resulted larger value ALPS-index.ALPS index robust under even when scanners used. ALPS influenced gradient axes, sequence. These factors should be uniformed planning studies. possibility develop DWI-ALPS three axes also suggested.

Language: Английский

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Magnetic ResonanceImages Implicate That Glymphatic Alterations Mediate Cognitive Dysfunction inAlzheimer Disease

Annals of Neurology, Journal Year: 2022, Volume and Issue: 93(1), P. 164 - 174

Published: Oct. 10, 2022

Objective The glymphatic system cleans amyloid and tau proteins from the brain in animal studies of Alzheimer disease (AD). However, there is no direct evidence showing this humans. Methods Participants (n = 50, 62.6 ± 5.4 years old, 36 women) with AD normal controls underwent positron emission tomography (PET), PET, structural T1‐weighted magnetic resonance imaging, neuropsychological evaluation. Whole‐brain activity was measured by diffusion tensor image analysis along perivascular space (DTI‐ALPS). Results ALPS‐indexes showed negative correlations deposition on PET images positive cognitive scores even after adjusting for age, sex, education, APOE4 genotype covariates multiple AD‐related regions (all p < 0.05). Mediation that ALPS‐index acted as a significant mediator between regional standardized uptake value ratios dysfunction correcting regions. These are responsible attention, memory, executive function, which vulnerable to sleep deprivation. Interpretation Glymphatic may act gray matter volumes. provide useful progression or treatment biomarkers patients an indicator modulation activity. ANN NEUROL 2023;93:164–174

Language: Английский

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The Glymphatic System in Humans: Investigations With Magnetic Resonance Imaging

Investigative Radiology, Journal Year: 2023, Volume and Issue: 59(1), P. 1 - 12

Published: March 10, 2023

Abstract The concept of the glymphatic system was proposed more than a decade ago as mechanism for interstitial fluid flow and waste removal in central nervous system. function has been shown to be particularly activated during sleep. Dysfunction implicated several neurodegenerative diseases. Noninvasive vivo imaging is expected useful elucidating pathophysiology these Currently, magnetic resonance most commonly used technique evaluate humans, large number studies have reported. This review provides comprehensive overview investigations human using imaging. can divided into 3 categories, including without gadolinium-based contrast agents (GBCAs), with intrathecal administration GBCAs, intravenous GBCAs. purpose examine not only movement brain parenchyma, but also dynamics perivascular subarachnoid spaces, well parasagittal dura meningeal lymphatics. Recent research even extended include eye inner ear. serves an important update guide future directions.

Language: Английский

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The relationship between inflammation, impaired glymphatic system, and neurodegenerative disorders: A vicious cycle

Neurobiology of Disease, Journal Year: 2024, Volume and Issue: 192, P. 106426 - 106426

Published: Feb. 6, 2024

The term "glymphatic" emerged roughly a decade ago, marking pivotal point in neuroscience research. glymphatic system, glial-dependent perivascular network distributed throughout the brain, has since become focal of investigation. There is increasing evidence suggesting that impairment system appears to be common feature neurodegenerative disorders, and this exacerbates as disease progression. Nevertheless, factors contributing dysfunction across most disorders remain unclear. Inflammation, however, suspected play role. Dysfunction can lead significant accumulation protein waste products, which trigger inflammation. interaction between inflammation cyclical potentially synergistic. Yet, current research limited, there lack comprehensive models explaining association. In perspective review, we propose novel model inflammation, impaired function, interconnected vicious cycle. By presenting experimental from existing literature, aim demonstrate that: (1) aggravates dysfunction, (2) exacerbated progression, (3) progression promotes Finally, implication proposed discussed.

Language: Английский

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The regulatory roles of motile cilia in CSF circulation and hydrocephalus

Fluids and Barriers of the CNS, Journal Year: 2021, Volume and Issue: 18(1)

Published: July 7, 2021

Cerebrospinal fluid (CSF) is an ultra-filtrated colorless brain that circulates within spaces like the ventricular cavities, subarachnoid space, and spine. Its continuous flow serves many primary functions, including nourishment, protection, waste removal.The abnormal accumulation of CSF in cavities triggers severe hydrocephalus. Accumulating evidence had indicated synchronized beats motile cilia (cilia from multiciliated cells or ependymal lining ventricles) provide forceful pressure to generate restrain maintain overall circulation spaces. In humans, disorders caused by defective and/or are generally referred as ciliopathies. The key role development its functioning has not been fully elucidated.In this review, we briefly discuss underlying We have reviewed ciliated existing for regulatory functional brain. further findings obtained their potential involvement Furthermore, review will reinforce idea master regulators movements, development, neuronal diseases.

Language: Английский

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Glymphatic clearance estimated using diffusion tensor imaging along perivascular spaces is reduced after traumatic brain injury and correlates with plasma neurofilament light, a biomarker of injury severity

Brain Communications, Journal Year: 2023, Volume and Issue: 5(3)

Published: Jan. 1, 2023

Abstract The glymphatic system is a perivascular fluid clearance system, most active during sleep, considered important for clearing the brain of waste products and toxins. Glymphatic failure hypothesized to underlie protein deposition in neurodegenerative disorders like Alzheimer’s disease. Preclinical evidence suggests that functioning also essential recovery from traumatic injury, which involves release debris toxic proteins need be cleared brain. In cross-sectional observational study, we estimated using diffusion tensor imaging along spaces, an MRI-derived measure water diffusivity surrounding veins periventricular region, 13 non-injured controls 37 subjects who had experienced injury ∼5 months previously. We additionally measured volume space T2-weighted MRI. plasma concentrations neurofilament light chain, biomarker severity, subset subjects. Diffusion spaces index was modestly though significantly lower with compared when covarying age. significantly, negatively correlated blood levels chain. Perivascular did not differ as correlate suggesting it may less sensitive injury-related changes. impairment after could due mechanisms such mislocalization channels, inflammation, proteinopathy and/or sleep disruption. promising method estimating clearance, additional work needed confirm results assess associations outcome. Understanding changes following inform novel therapies improve short-term reduce later risk neurodegeneration.

Language: Английский

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The Dynamic Relationship between the Glymphatic System, Aging, Memory, and Sleep

Biomedicines, Journal Year: 2023, Volume and Issue: 11(8), P. 2092 - 2092

Published: July 25, 2023

The process of memory entails the activation numerous neural networks and biochemical pathways throughout brain. phenomenon decline in relation to aging has been subject extensive research for several decades. correlation between is intricate various aspects consider. Throughout process, there are alterations that take place within brain and, as expected, affect other functions have already linked its function such involving microcirculation sleep. Recent studies provide an understanding how these mechanisms may be interconnected through relatively new concept glymphatic system. system strongly correlated sleep processes. Sleep helps remove waste solutes. Astrocytes expand contract form channels cerebrospinal fluid (CSF) wash eliminate waste. However, details not totally elusive, but discovery what we call enables us connect many pieces physiology understand factors interplay them. Thus, purpose this review discuss system, sleep, memory, a network complex dynamic interactions.

Language: Английский

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The glymphatic system and Amyotrophic lateral sclerosis

Progress in Neurobiology, Journal Year: 2024, Volume and Issue: 234, P. 102571 - 102571

Published: Jan. 22, 2024

Language: Английский

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Assessment of glymphatic function and white matter integrity in children with autism using multi-parametric MRI and machine learning

European Radiology, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Language: Английский

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The Pathogenesis Based on the Glymphatic System, Diagnosis, and Treatment of Idiopathic Normal Pressure Hydrocephalus

Clinical Interventions in Aging, Journal Year: 2021, Volume and Issue: Volume 16, P. 139 - 153

Published: Jan. 1, 2021

Abstract: Idiopathic normal pressure hydrocephalus (iNPH) is a rare neurological disorder with no clear prevalence factors and significant danger to the elderly. The intracranial glymphatic system internal environment that maintains brain survival metabolism, thus fluid exchange changes in under various pathological conditions can provide important insights into pathogenesis differential diagnosis of many neurodegenerative diseases such as iNPH. iNPH be diagnosed using combination clinical symptoms, imaging findings history, cerebrospinal biomarkers due disorder. However, only few researchers have linked two. Shunt surgery improve disorders patients, surgical approach determined trials. Therefore, we composed this review future opportunity for elucidating based on system, link treatment will new medical research Keywords: idiopathic hydrocephalus, pathogenesis, diagnostic methods, shunt

Language: Английский

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