Cerebral hemodynamic

PURPOSE: In patients undergoing endovascular thrombectomy (EVT) with acute ischemic stroke (AIS), dynamic cerebral autoregulation (dCA) may minimize neurological injury from blood pressure fluctuations. This study set out to investigate the function of dCA in predicting clinical outcomes following EVT. METHODS: 43 AIS of the middle cerebral or internal carotid artery patients underwent with EVT, and 43 healthy individuals (controls) were enrolled in this case control research...

Salvage treatment of postclipping recurrent aneurysms remains challenging.1,2 The salvage microsurgical clipping is a possible intervention but sometimes difficult because of tissue adhesions around the aneurysm and previously installed clips; therefore, salvage coil embolization may have certain advantages.1-5 However, when coil embolization is not applicable,6 microsurgical clipping is a stand-alone curative treatment, requiring proficient and reliable microsurgical techniques. This article describes a unique case of a 70-year-old female patient complaining of a severe headache with subarachnoid hemorrhage due to a recurrent ruptured left internal carotid-posterior communicating artery aneurysm after microsurgical clipping 23 years ago...

INTRODUCTION: Mutations of the phosphatase and tensin homolog (PTEN) gene have been associated with a spectrum of disorders called PTEN hamartoma tumor syndrome, which predisposes the individual to develop various types of tumors and vascular anomalies. Its phenotypic spectrum includes Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome (BRRS), Proteus syndrome, autism spectrum disorders (ASD), some sporadic cancers, Lhermitte-Duclos disease (LDD), and various types of associated vascular anomalies...

INTRODUCTION: In the current times, fetal growth monitoring has become readily available with the help of Doppler ultrasound. Identification of pregnancies that are at risk for perinatal morbidity and mortality has been a primary goal of obstetric care. Doppler study is a fast, non-invasive test that provides significant information about the hemodynamic status of the fetus. It is an efficient diagnostic modality to assess fetal compromise, which helps in timely intervention in high-risk pregnancies for better perinatal outcomes...

The Angiovac aspiration system has been used successfully for the removal of intravascular material or thrombus in the right-sided heart structures, vena cava, implantable cardiac defibrillator, or other devices. For infective endocarditis, it is reserved for the patients who warrant but are not good candidates for the surgery. The evidence regarding Angiovac aspiration of the infective endocarditis of the left-sided heart valves is scarce. The risk of complications, including thrombi fragmentation leading to systemic embolization, damage to the cardiac structures and tissue, and hemodynamic instability, precludes the widespread use of this procedure, especially for the left-sided lesions...

BACKGROUND: Carotid atherosclerosis is often mentioned as one of the main causes of stroke. Currently, embolization is considered the most common mechanism that causes ischemic strokes due to atherosclerotic lesions in the carotid artery. Transcranial Doppler (TCD) ultrasound provides relatively inexpensive, noninvasive, real-time measurement of blood flow characteristics and cerebrovascular hemodynamics within brain arteries. The pulsatile index measured by transcranial Doppler is a parameter that indicates the degree of elasticity of the blood vessels of the brain...

The influence of the aneurysm evolution on the hemodynamic characteristic of the blood flow inside the sac region is comprehensively investigated. By using the computational method, the blood flow through the vessel and aneurysm of the sac region is examined to find the role of aneurysm evolution on the wall shear stress, pressure, and risk of aneurysm rupture. Three different models of ICA aneurysms are chosen for the investigation of the aneurysm evolution at risk of rupture. Obtained data shows that the evolution of the aneurysm decreases the wall shear stress and pressure on the sac surface while an oscillatory index of blood increases on the aneurysm wall...

Fat embolism syndrome (FES) is a rare complication of long bone fractures, with fulminant FES developing within 12 h of injury and often proving fatal (Shaikh, 2009 [1]). Here, we present a case of fulminant FES in a patient who developed sudden right heart failure after undergoing external fixation of a lower leg fracture and required veno-arterial extracorporeal membrane oxygenation (VA-ECMO). A 79-year-old woman injured in a traffic accident was transferred to our emergency department. Upon arrival, her level of consciousness deteriorated, and she developed circulatory failure...

INTRODUCTION: The discourse surrounding differences in cerebral hemodynamics and clinical outcomes among male and female patients treated with mechanical thrombectomy (MT) for acute ischemic stroke (AIS) remains unresolved. We aimed to elucidate these differences by employing computed tomography perfusion (CTP) imaging before MT and examining the influence of perfusion deficits on the 90-day functional outcome. METHODS: This single-center retrospective analysis involved patients with anterior circulation AIS treated with MT at the Comprehensive Stroke Center, University Hospital, Krakow from January 2019 to July 2023...

BACKGROUND: Vasodilation, autoregulation, and rising arterial pressure are three common concepts in cerebral compression, believed to improve cerebral blood flow to maintain the brain's nutrition. However, these concepts are unclear, unproven, and based on assumptions. This study aimed to correlate cerebral circulation with alterations of vital signs and to evaluate the above concepts based on physics and hemodynamics. METHODS: Without new animal experiments, a large amount of data: recording of vital signs, long movies of cerebral circulation, and numerous photos of histological examination and microvessels obstruction in cerebral compression in cats was studied, and only partial and preliminary results were reported in 1970...

Objective This study investigated the global correlation between cerebral blood flow (CBF) decline and increased venous prominence, utilizing arterial spin labeling (ASL) and susceptibility-weighted imaging (SWI) MRI techniques. Methods The study was conducted at the Department of Diagnostic Imaging, St. Marina University Hospital, Varna, Bulgaria. Through a retrospective analysis, we examined data from 115 patients undergoing neurological assessment. CBF decline was assessed through ASL MRI, while global venous visibility was evaluated using SWI MRI...

Early breach of the blood-brain barrier (BBB) and consequently extravasation of blood-borne substances into the brain parenchyma is a common hallmark of ischemic stroke. Although BBB breakdown is associated with an increased risk of cerebral hemorrhage and poor clinical prognosis, the cause and mechanism of this process are largely unknown. The aim of this study was to establish an imaging and analysis protocol which enables investigation of the dynamics of BBB breach in relation to hemodynamic properties along the arteriovenous axis...

Spreading depolarizations (SDs) are a marker of brain injury and have a causative effect on ischemic lesion progression. The hemodynamic responses elicited by SDs are contingent upon the metabolic integrity of the affected tissue, with vasoconstrictive reactions leading to pronounced hypoxia often indicating poor outcomes. The stratification of hemodynamic responses within different cortical layers remains poorly characterized. This pilot study sought to elucidate the depth-specific hemodynamic changes in response to SDs within the gray matter of the gyrencephalic swine brain...

BACKGROUND: Silent magnetic resonance angiography (MRA) mitigates metal artifacts, facilitating clear visualization of neck remnants after stent and coil embolization of cerebral aneurysms. This study aims to scrutinize hemodynamics at the neck remnant by employing silent MRA and computational fluid dynamics. OBSERVATIONS: The authors longitudinally tracked images of a partially thrombosed anterior communicating artery aneurysm's neck remnant, which had been treated with stent-assisted coil embolization, using silent MRA over a decade...

The efficacy of extracranial-intracranial (EC-IC) bypass in preventing ischemic stroke progression and recurrence is controversial. As per the current hypothesis, EC-IC bypass is most beneficial for patients with persistent hemodynamic insufficiency. Hence, various approaches have been used to evaluate hemodynamic insufficiency, including repeated single photon emission CT (SPECT) imaging or continuous monitoring of cerebral flow with transcranial Doppler ultrasound (TCD). However, both modalities are time- and resource-intensive...

BACKGROUND: Recently, the American Heart Association released a statement calling for research examining the appropriate age to transition from the neonatal to pediatric cardiopulmonary resuscitation approach to resuscitation. AIM: To compare neonatal and pediatric resuscitation approach by using either continuous chest compression with asynchronized ventilation (CCaV) or continuous chest compression superimposed with sustained inflation (CC + SI) during infant cardiopulmonary resuscitation...

Focused ultrasound (FUS) stimulation is a promising neuromodulation technique with the merits of non-invasiveness, high spatial resolution, and deep penetration depth. However, simultaneous imaging of FUS-induced brain tissue displacement and the subsequent effect of FUS stimulation on brain hemodynamics has proven challenging thus far. In addition, earlier studies lack in situ confirmation of targeting except for the magnetic resonance imaging-guided FUS system-based studies. The purpose of this study is 1) to introduce a fully ultrasonic approach to in situ target, modulate neuronal activity, and monitor the resultant neuromodulation effect by respectively leveraging displacement imaging, FUS, and functional ultrasound (fUS) imaging, and 2) to investigate FUS-evoked cerebral blood volume (CBV) response and the relationship between CBV and displacement...

BACKGROUND: In epilepsy, the ictal phase leads to cerebral hyperperfusion while hypoperfusion is present in the interictal phases. Patients with Alzheimer's disease (AD) have an increased prevalence of epileptiform discharges and a study using intracranial electrodes have shown that these are very frequent in the hippocampus. However, it is not known whether there is an association between hippocampal hyperexcitability and regional cerebral blood flow (rCBF). The objective of the study was to investigate the association between rCBF in hippocampus and epileptiform discharges as measured with ear-EEG in patients with Alzheimer's disease...

Computational fluid dynamics (CFD) has been utilized to calculate hemodynamic parameters in anterior communicating artery aneurysm (AComA), which is located at a junction between left and right A1 and A2 segments. However, complete or half circle of Willis (CoW) models are used indiscriminately. This study aims to suggest recommendations for determining suitable CoW model. Five patient-specific CoW models with AComA were used, and each model was divided into complete, left-half, and right-half models. After validating the CFD using a flow experiment, the hemodynamic parameters and flow patterns in five AComAs were compared...

Mechanisms behind the protective effects of aerobic exercise on brain health remain elusive but may be vascular in origin and relate to cerebral pulsatility. This pilot study investigated the effects of 12 wks aerobic exercise training on cerebral pulsatility and its vascular contributors (large artery stiffness, characteristic impedance) in at-risk middle-aged adults. 28 inactive middle-aged adults with elevated blood pressure or stage 1 hypertension were assigned to either moderate/vigorous aerobic exercise training (AET) for 3 d/wk or no-exercise control (CON) group...