Increased Risk of Recurrent Stroke in Symptomatic Large Vessel Disease With Impaired BOLD Cerebrovascular Reactivity

Stroke, Год журнала: 2024, Номер 55(3), С. 613 - 621

Опубликована: Фев. 8, 2024

Impaired cerebrovascular reactivity (CVR) has been correlated with recurrent ischemic stroke. However, for clinical purposes, most CVR techniques are rather complex, time-consuming, and lack validation quantitative measurements. The recent adaptation of a standardized hypercapnic stimulus in combination blood-oxygenation-level-dependent (BOLD) magnetic resonance imaging signal as surrogate cerebral blood flow offers potential universally comparable assessment. We investigated the association between impaired BOLD-CVR risk events.

Язык: Английский

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Functional MRI in Neuro-Oncology: State of the Art and Future Directions

Radiology, Год журнала: 2023, Номер 308(3)

Опубликована: Сен. 1, 2023

Since its discovery in the early 1990s, functional MRI (fMRI) has been used to study human brain function. One well-established application of fMRI clinical setting is neurosurgical planning patients with tumors near eloquent cortical areas. Clinical aims preoperatively identify cortices that serve essential functions daily life, such as hand movement and language. The primary goal neurosurgery maximize tumor resection while sparing adjacent tumor. When a lesion presents vicinity an cortex, surgeons may use plan their best surgical approach by determining proximity regions activation, providing guidance for awake surgery intraoperative mapping. acquisition requires patient preparation prior imaging, determination paradigms, monitoring performance, both processing analysis images. Interpretation maps strong understanding neuroanatomy familiarity technical limitations frequently present including neurovascular uncoupling, compliance, data analysis. This review discusses neuro-oncology, relevant ongoing research topics, prospective future developments this exciting discipline.

Язык: Английский

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Cerebral blood flow, cerebrovascular reactivity and their influence on ventilatory sensitivity

Experimental Physiology, Год журнала: 2021, Номер 106(7), С. 1425 - 1448

Опубликована: Май 1, 2021

What is the topic of this review? Cerebrovascular reactivity to CO2 , which a principal factor in determining ventilatory responses through role plays cerebral extra- and intracellular pH. advances does it highlight? Recent animal evidence suggests central chemoreceptor vasculature may demonstrate regionally heterogeneous cerebrovascular potentially as protective mechanism against excessive washout from chemoreceptors, thereby allowing ventilation reflect systemic acid-base balance needs (respiratory changes PaCO2 ) rather than solely needs. Ventilation per se not influence independent .Alveolar blood flow are both predominantly regulated by arterial gases, especially PCO2 so intricately entwined. In review, fundamental mechanisms underlying control breathing covered. We discuss interaction its with responsiveness well lack itself on reactivity. briefly summarize effects hypoxaemia relationship between response PO2 . then highlight key methodological considerations regarding sensitivity, including following: regional heterogeneity reactivity; pharmacological approach for reduction flow; assessment techniques; mean pressure; sex-related differences. Finally, we context high altitude congestive heart failure. Future research directions pertinent questions interest highlighted throughout.

Язык: Английский

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Evidence for direct CO₂‐mediated alterations in cerebral oxidative metabolism in humans

Acta Physiologica, Год журнала: 2024, Номер 240(9)

Опубликована: Июль 3, 2024

How the cerebral metabolic rates of oxygen and glucose utilization (CMRO

Язык: Английский

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Multiparametric Brain Hemodynamics Imaging Using a Combined Ultrafast Ultrasound and Photoacoustic System

Advanced Science, Год журнала: 2024, Номер 11(31)

Опубликована: Июнь 17, 2024

Abstract Studying brain‐wide hemodynamic responses to different stimuli at high spatiotemporal resolutions can help gain new insights into the mechanisms of neuro‐ diseases and ‐disorders. Nonetheless, this task is challenging, primarily due complexity neurovascular coupling, which encompasses interdependent parameters including cerebral blood volume (CBV), flow (CBF), oxygen saturation (SO 2 ). The current brain imaging technologies exhibit inherent limitations in resolution, sensitivity, depth, restricting their capacity comprehensively capture intricacies functions. To address this, a multimodal functional ultrasound photoacoustic (fUSPA) platform reported, integrates ultrafast multispectral methods compact head‐mountable device, quantitatively map individual dynamics CBV, CBF, SO as well contrast agent enhanced resolutions. Following systematic characterization, fUSPA system applied study cerebrovascular reactivity (CVR) single‐vessel resolution via relative changes response hypercapnia stimulation. These results show that cortical veins arteries differences CVR stimulated state consistent anti‐correlation CBV oscillations during resting state, demonstrating multiparametric system's unique capabilities investigating complex

Язык: Английский

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Compromised cerebrovascular reactivity related to presence of white matter hyperintensities in cryptogenic stroke with right-to-left shunts

Journal of Stroke and Cerebrovascular Diseases, Год журнала: 2025, Номер 34(2), С. 108223 - 108223

Опубликована: Янв. 7, 2025

This study investigates cerebrovascular reactivity (CVR) changes in cryptogenic stroke (CS) patients with right-to-left shunts (RLS) and evaluates the relationship between CVR white matter hyperintensities (WMHs). The breath-holding index (BHI), representing CVR, was measured from middle cerebral artery (MCA) using method. WMHs were defined as clearly hyperintense areas on 3T magnetic resonance imaging (MRI), assessed separately periventricular (PVH) deep (DWMH). RLS diagnosed based a contrast-enhanced transcranial Doppler (c-TCD) examination. Among 260 CS 128 controls, BHI significantly lower groups (0.68±0.27 vs. 0.83±0.31, P<0.001), particularly those (0.64±0.28 0.71±0.25,P = 0.030). exhibited than without (0.50±0.22 vs.0.60±0.35, P 0.012), PVH showed compared to DWMH (0.45±0.24 vs.0.58±0.16, 0.003). A negative correlation found WMH severity (0.60±0.35 vs.0.51±0.21 vs.0.48±0.20 vs.0.38±0.28, 0.025). Reduced an independent risk factor for (OR 0.283; 95 % CI 0.081-0.995, 0.049). patients, especially RLS, show reduced which correlates location of WMHs. These findings suggest that may contribute development patients.

Язык: Английский

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Comparison of safety and efficacy of different endovascular treatments for symptomatic intracranial atherosclerotic stenosis: results from a single center

Frontiers in Neurology, Год журнала: 2025, Номер 16

Опубликована: Март 5, 2025

Symptomatic intracranial atherosclerotic stenosis (sICAS) is one of the common causes ischemic stroke. However, treatment sICAS has remained a challenge in past with unfavorable findings. This study aimed to evaluate effectiveness and safety different endovascular methods for sICAS. The involved 154 patients who received at Qingdao University Hospital between January 2021 October 2023. Based on characteristics lesions, three types treatments were performed: bare metal stent group (BMS group), drug-coated balloon (DCB drug-eluting (DES group). primary endpoints included incidence in-stent restenosis (ISR) 6-month, periprocedural complications, rate stroke recurrence area stented artery during follow-up period, modified Rankin score (mRS) discharge, 1-month, 3-month, 6-month after stenting. perioperative complications did not differ significantly groups (11.3% BMS group, 8.0% DCB 6.1% DES p = 0.776). All (154/154) had successful reperfusion treatment. was 4.5% (7/154), 5 (7.0%) 1 (2.0%) patient (3.0%) group. [35.2% (25/71)] tended be higher than that [6.0% (3/50)] [9.1% (3/33)]. In multivariate logistic regression analysis, strategy vessel distribution significant independent risk factors ISR within 6 months (p < 0.05). Adverse events success rates following implantation are comparable across therapy individuals When compared BMS, DES, reduce ISR, advantages appearing greater some high-risk ICAS.

Язык: Английский

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Perfusion MRI using endogenous deoxyhemoglobin as a contrast agent: Preliminary data

Magnetic Resonance in Medicine, Год журнала: 2021, Номер 86(6), С. 3012 - 3021

Опубликована: Окт. 22, 2021

Purpose To demonstrate the feasibility of mapping cerebral perfusion metrics with BOLD MRI during modulation pulmonary venous oxygen saturation. Methods A gas blender a sequential delivery breathing circuit was used to implement rapid isocapnic changes in partial pressure arterial blood. Partial initially lowered baseline 40 mmHg. It then rapidly raised 95 mmHg for 20 s before returning baseline. The induced deoxyhemoglobin concentration were tracked over time using 6 healthy subjects and 1 patient steno‐occlusive disease. signal change, contrast‐to‐noise ratio, delay calculated. Perfusion such as mean transit time, relative blood volume, flow calculated parametrized method mono‐exponential residue function. An input function from within middle artery scale volume calculate absolute flow. Results In normal subjects, average gray white matter were: change = 6.3 ± 1.2% 2.5 0.6%, ratio 4.3 1.3 2.6 0.7, 2.3 0.6 3.6 0.7 s, 3.9 5.5 3.7 0.9 1.6 0.4, 70.1 8.3 20.6 4.0, 4.1 mL/100 g 1.8 0.5 g, 97.2 18.7 g/min 28.7 5.9 g/min. Conclusion This study demonstrates that abrupt can noninvasive vascular contrast agent may be imaging.

Язык: Английский

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Hemodynamic Imaging in Cerebral Diffuse Glioma—Part A: Concept, Differential Diagnosis and Tumor Grading

Cancers, Год журнала: 2022, Номер 14(6), С. 1432 - 1432

Опубликована: Март 10, 2022

Diffuse gliomas are the most common primary malignant intracranial neoplasms. Aside from challenges pertaining to their treatment-glioblastomas, in particular, have a dismal prognosis and currently incurable-their pre-operative assessment using standard neuroimaging has several drawbacks, including broad differentials diagnosis, imprecise characterization of tumor subtype definition its infiltration surrounding brain parenchyma for accurate resection planning. As pathophysiological alterations tissue tightly linked an aberrant vascularization, advanced hemodynamic imaging, addition other innovative approaches, attracted considerable interest as means improve diffuse glioma characterization. In present part A our two-review series, fundamental concepts, techniques parameters imaging discussed conjunction with potential role differential diagnosis grading gliomas. recent evidence on dynamic susceptibility contrast, contrast-enhanced arterial spin labeling magnetic resonance reviewed together perfusion-computed tomography. While these provided encouraging results terms sensitivity specificity, limitations deriving lack standardized acquisition processing prevented widespread clinical adoption, current efforts aimed at overcoming existing barriers.

Язык: Английский

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A systematic review of the association between dementia risk factors and cerebrovascular reactivity

Neuroscience & Biobehavioral Reviews, Год журнала: 2023, Номер 148, С. 105140 - 105140

Опубликована: Март 20, 2023

Cumulative evidence suggests that impaired cerebrovascular reactivity (CVR), a regulatory response critical for maintaining neuronal health, is amongst the earliest pathological changes in dementia. However, we know little about how CVR affected by dementia risk, prior to disease onset. Understanding this relationship would improve our knowledge of pathways and help inform preventative interventions. This systematic review investigates 59 studies examining (measured magnetic resonance imaging) modifiable, non-modifiable, clinical risk factors We report non-modifiable (older age apolipoprotein ε4), some modifiable (diabetes, traumatic brain injury, hypertension) (stroke, carotid artery occlusion, stenosis) were consistently associated with reduced CVR. also note lack conclusive on other behavioural such as physical inactivity, obesity, or depression, affect explores biological mechanisms underpinning these brain-behaviour associations, highlights evident gaps literature, identifies could be managed preserve an effort prevent

Язык: Английский

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