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Clevenger Amy Christine AC The Children's Hospital of Philadelphia, Anesthesiology and Critical Care Medicine, Philadelphia, Pennsylvania, United States ; - - 2014
Introduction: Modification of cerebral perfusion pressure and cerebral blood flow are crucial components of the therapies designed to reduce secondary damage after traumatic brain injury (TBI). Previously we documented a robust decrease in cerebral blood flow (CBF) after rapid sagittal head rotation in our well-validated animal model of diffuse TBI. ...
Biasetti Jacopo J Department of Solid Mechanics, School of Engineering Sciences, KTH Royal Institute of Technology, Stockholm, Sweden - - 2014
Shear-induced migration of red blood cells (RBCs) is a well-known phenomenon characterizing blood flow in the small vessels (micrometre to millimetre size) of the cardiovascular system. In large vessels, like the abdominal aorta and the carotid artery (millimetre to centimetre size), the extent of this migration and its interaction with ...
Lukasiewicz A A Department of Vascular Surgery, Regional Specialty Hospital, Grudziadz, Poland - - - 2014
Carotid endarterectomy (CEA) is well recognized procedure in the treatment of patients with significant symptomatic internal carotid artery (ICA) stenosis. Operation reconstitutes physiologic blood flow in the ICA. The influence of CEA on cerebral perfusion (CP) is not well established. Some data suggest increased CP after stenosis correction however evidence ...
Yakovlev D S DS Volgograd State Medical University, Volgograd, Russia, - - 2014
We studied the ability of predominantly 5-HT2A receptor antagonists to prevent a serotonin-induced change of blood flow in the carotid vessels of rats with experimental serotonin-induced spasm. Ritanserin, ketanserin, and 5-HT2A receptor antagonist RU-476 reduced the effect of serotonin on the blood fl ow velocity in the internal carotid artery ...
Iwata Tomonori T Department of Stroke Treatment, Shonan Kamakura General Hospital Stroke Center, Okamoto 1370-1, Kamakura City, Kanagawa 247-8533, - - 2014
Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent CHS, cerebral hyperperfusion phenomenon (CHP) must be detected early. SPECT is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. ...
Droste Dirk W DW Department of Neurology, Centre Hospitalier de Luxembourg, Luxembourg, - - 2014
Background: A Mediterranean diet, with and without small daily amounts of red wine, and physical activity reduce the risk of cerebrovascular disease and improve cognition. An increase in cerebral blood flow may be the underlying mechanism. Under normal conditions, cerebral blood flow velocity changes in the internal carotid arteries and ...
Zhu Wenhui W The Department of Ophthalmology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China, - - 2014
To evaluate retrobulbar and common carotid artery (CCA) haemodynamics and CCA wall thickness in the patients with acute unilateral non-arteritic anterior ischaemic optic neuropathy (NAION) by colour Doppler imaging (CDI). Twenty-two patients with acute unilateral NAION and 28 age- and sex-matched controls were included in this prospective study. By CDI, ...
Aristokleous Nicolas - - 2014
This paper aims at evaluating the changes that head rotation poses on morphological and flow characteristics of the carotid bifurcation (CB) and on the distribution of parameters that are regarded as important in atherosclerosis development, such as relative particle residence time (RRT), normalized oscillatory shear index (nOSI), and helicity (HL). ...
Blehar David J DJ University of Massachusetts Medical School, 55 Lake Ave N, Worcester, MA 01655. Electronic address: - - 2014
Assessment of volume status remains a challenge in critical care. Our purpose was to determine if Doppler waveform analysis of carotid artery blood flow correlates with changes in volume status. Dehydrated patients receiving an intravenous fluid bolus were enrolled with exclusions including age less than 18 years, pregnancy, vasopressor administration, ...
Ogoh Shigehiko S From the *Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama; †Research Institute of Physical Fitness, Japan Women's College of Physical Education, Tokyo; ‡Department of Environmental Physiology for Exercise, Osaka City University Graduate School of Medicine; §Faculty of Health Sciences, Morinomiya University of Medical Sciences, Osaka, Japan; ‖Department of Anesthesia, The Copenhagen Muscle Research Center, University of Copenhagen, Copenhagen, Denmark; and ¶Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, - - 2014
Spatially resolved near-infrared spectroscopy-determined frontal lobe tissue oxygenation (ScO2) is reduced with administration of phenylephrine, while cerebral blood flow may remain unaffected. We hypothesized that extracranial vasoconstriction explains the effect of phenylephrine on ScO2. We measured ScO2 and internal and external carotid as well as vertebral artery blood flow in ...
Harrison Gareth J GJ The Regional Vascular Unit, Liverpool Royal Hospital, Liverpool, United Kingdom. Electronic address: - - 2014
Meta-analysis supports patch angioplasty after carotid endarterectomy (CEA); however, studies indicate considerable variation in practice. The hemodynamic effect of a patch is unclear and this study attempted to elucidate this and guide patch width selection. Four groups were selected: healthy volunteers and patients undergoing CEA with primary closure, trimmed patch ...
Ogoh Shigehiko S Toyo - - 2014
The present study examined to what extent an acute bout of hypotension influences blood flow in the external carotid artery (ECA) and the corresponding implications for blood flow regulation in the internal carotid artery (ICA). Nine healthy male participants were subject to an abrupt decrease in arterial pressure via the ...
Li Zhi-Yong ZY a School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096 , - - 2014
The aim of this study is to investigate the blood flow pattern in carotid bifurcation with a high degree of luminal stenosis, combining in vivo magnetic resonance imaging (MRI) and computational fluid dynamics (CFD). A newly developed two-equation transitional model was employed to evaluate wall shear stress (WSS) distribution and ...
Raghuvir Pai B B Department of Mechanical Engineering, MIT, Manipal, - - 2014
Gravity associated with postural changes has a strong bearing on haemodynamics of blood flow in arteries. Its effect on stenosed cases has not been widely investigated. In the present study, variation observed in blood flow during postural changes is investigated for different conditions like standing, sleeping and head-down position. A ...
Sørensen H H Department of Anaesthesiology, The Copenhagen Muscle Research Centre, Rigshospitalet, University of Copenhagen, Copenhagen, - - 2014
/st>Phenylephrine and ephedrine affect frontal lobe oxygenation () differently when assessed by spatially resolved near infrared spectroscopy. We evaluated the effect of phenylephrine and ephedrine on extra- vs intra-cerebral blood flow and on . /st>In 10 healthy males (age 20-54 yr), phenylephrine or ephedrine was infused for an ∼20 mm ...
Lisowska A A Department of Cardiology, Medical University of Bialystok, Bialystok, Poland - - - 2014
Aim: Contrast-enhanced ultrasound imaging of the carotid arteries (CECU) permits direct, real-time visualization of neovascularization in atherosclerotic plaques and is a confirmed predictor of unstable atheromatous lesions. The aim of the study was the assessment of a new, automatically measured index of intensity in quantitative estimation of the contrast flow ...
Jacobs Bradley S BS From the Department of Neurology (B.S.J.), Wright State University Boonshoft School of Medicine, Dayton, OH; and the Departments of Neurology and Radiology (F.T.N.), Medical College of Georgia at Georgia Regents University, - - 2014
Vascular cognitive impairment may be related to clinically apparent stroke, silent smaller strokes, or perhaps zones of incomplete infarction related to cerebral hypoperfusion.(1,2) Flow limiting carotid stenosis or complete occlusion is associated with hemodynamic failure and poorer cognition.(3,4) Improving cerebral blood flow in such patients via revascularization procedures such as ...
Ihara Masafumi M Department of Stroke and Cerebrovascular Diseases, National Cerebral and Cardiovascular Center, Osaka, - - 2014
Vascular dementia or vascular cognitive impairment occurs as a result of persistently compromised blood flow to the brain and represents the second most common type of dementia after Alzheimer's disease. In order to investigate its underlying mechanisms, a mouse model of chronic cerebral hypoperfusion has been developed, which involves the ...
Nybo Lars L Department of Nutrition, Exercise and Sport Sciences, University of Copenhagen Copenhagen, - - 2014
The present study evaluated the influence of intranasal cooling with balloon catheters, increased nasal ventilation, or percutaneous cooling of the carotid arteries on cerebral temperature balance and oxygenation in six healthy male subjects. Aortic arch and internal jugular venous blood temperatures were measured to assess the cerebral heat balance and ...
Tan Maw Pin MP Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia - - 2014
Carotid sinus hypersensitivity (CSH) is associated with syncope, unexplained falls, and drop attacks in older people but occurs asymptomatically in 35% of community-dwelling elders. We hypothesized that impaired cerebral autoregulation is associated with the conversion of asymptomatic CSH to symptomatic CSH. We therefore conducted a case-control study evaluating individuals with ...
Kröner Eleanore S J ES Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands; Interuniversity Cardiology Institute of The Netherlands, Utrecht, The - - 2013
To explore differences in arterial stiffness of the aorta and carotid artery, assessed by pulse wave velocity (PWV), to evaluate the blood flow volume distribution towards the carotid circulation and to assess the effect of aging on the coupling between aortic and carotid PWV using velocity-encoded magnetic resonance imaging (MRI). ...
Oikawa Kohki - - 2013
The aim of this study was to determine whether the ratio of blood flow contralateral-to-affected asymmetry in the cerebellar hemisphere to blood flow affected-to-contralateral asymmetry in the middle cerebral artery (MCA) territory (ARcbl/ARMCA) on preoperative brain perfusion SPECT could identify patients at risk for new cerebral ischemic events after carotid ...
Sato Kenichi - - 2013
Angiography-based balloon test occlusion (BTO) has been empirically used to predict tolerance to permanent carotid artery occlusion. We tested the hypothesis that the laterality of the hemispheric circulation time (HCT) of the contrast medium at cerebral angiography would reflect bilateral asymmetry of the cerebral blood flow (CBF) during BTO. Thirty-one ...
Kawai Nobuyuki - - 2013
The aim of the present study is the characterization of hemodynamics to predict hyperperfusion syndrome (HPS) after carotid artery stenting (CAS) with positron emission tomography (PET) obtained before and on the first day after the treatment. Cerebral perfusion and oxygen metabolism were evaluated by (15)O-gas PET in 18 patients with ...
Ito Kenji - - 2013
Preoperative assessment of intracranial collateral circulation is helpful in predicting cerebral ischemia during surgical procedures for cervical internal carotid artery (ICA) stenosis. However, magnetic resonance angiography (MRA) and other less-invasive techniques cannot evaluate collateral blood flow because these techniques are nonselective. Hence, by using a newly developed selective MRA technique, ...
Lucatelli Pierleone - - 2013
Altered carotid blood flow velocities (CFV) have a complex background but the underlying genetic contribution is still unclear. We sought to evaluate the influence of genetics, shared and unshared environmental components on individual differences of CFV. 193 healthy twin pairs, 126 monozygotic (MZ) and 67 dizygotic (DZ) (mean age 53 ± 14 ...
Gong Chi-Li CL Department of Physiology, School of Medicine, China Medical University, - - 2013
The common carotid artery (CCA) supplies intra- and extra-cranial vascular beds. An area in the medulla controlling CCA blood flow is defined as the dorsal facial area (DFA) by Kuo et al. in 1987. In the DFA, presynaptic nitrergic and/or glutamatergic fibers innervate preganglionic nitrergic and/or cholinergic neurons which give ...
Pennekamp C W A - - 2013
This study assessed the value of cerebral near-infrared spectroscopy (NIRS) and transcranial Doppler (TCD) in relation to electroencephalography (EEG) changes for the detection of cerebral hypoperfusion necessitating shunt placement during carotid endarterectomy (CEA). This was a prospective cohort study. Patients with a sufficient TCD window undergoing CEA from February 2009 ...
Attigah N - - 2013
Aim: Aim of the paper was to assess the reliability of preoperative cross-flow determination by transcranial Doppler measurement (TCD) to detect clamping ischemia in patients undergoing carotid endarterectomy with selective shunting. Methods: Retrospective one-to-one matched-pair analysis of 72 patients undergoing carotid endarterectomy with preoperative TCD scanning. Matching criteria were gender, ...
Kabinejadian Foad - - 2013
In the present study, a novel carotid covered stent design has been developed. Prototypes of different geometrical design parameters have been fabricated and their performance has been evaluated in vitro under physiological pulsatile flow condition, utilizing flow visualization (dye injection), and particle image velocimetry techniques. These evaluations include the assessment ...
Bain Anthony Richard - - 2013
We investigated; 1) the regional distribution of cerebral blood flow (CBF), 2) the influence of end-tidal PCO2 (PETCO2) on CBF, and 3) the potential for an extracranial blood steal from the anterior brain region during passive hyperthermia. Nineteen (13 male) volunteers underwent supine passive heating until a steady state esophageal ...
Tao Yuehui - - 2013
Measurement of blood flow by cine phase-contrast MRI is a valuable technique in the study of arterial disease but is time consuming, especially for multi-slice (4D) studies. Compressed sensing is a modern signal processing technique that exploits sparse signal representations to enable sampling at lower than the conventional Nyquist rate. ...
Wu Tung-Hsin - - 2013
Traditional digital subtraction angiography (DSA) provides detailed spatial resolution in the treatment of cerebrovascular disease. However, the available temporal information is often underutilized. The purpose of this study is to use deformable image registration with DSA to quantify the hemodynamic improvement of intracranial vessels after carotid stenting. Eighteen patients with ...
Li Guang G Research Imaging Institute, University of Texas Health Science Center, San Antonio, Texas 78229, - - 2013
We tested the hypothesis that retinal blood flow has a postocclusive reactive hyperemia response modulated by occlusion duration and metabolic activity, and that choroidal blood flow does not. Anesthetized and paralyzed rats (n = 34) were studied. Retinal and choroidal blood flow was measured by laser speckle imaging and laser ...
Harloff A - - 2013
To test the feasibility of four-dimensional (4D) flow MRI to quantify the systolic wall shear stress (WSSsystole) and oscillatory shear index (OSI) in high-grade internal carotid artery (ICA) stenosis before and after endarterectomy (CEA). Twenty patients with ≥60 % ICA stenosis were prospectively and consequently included. Four-dimensional flow MRI was used ...
Willie Christopher K - - 2013
The inter-individual variation in ventilatory acclimatization to high altitude (HA) is likely reflected in variability in the cerebrovascular responses to HA, particularly between brain regions displaying disparate hypoxic sensitivity. We assessed regional differences in CBF measured with Duplex ultrasound of the left internal carotid and vertebral arteries. End-tidal PCO2, SpO2, ...
Ghilardi S - - 2013
Aim: Carotid endarterectomy is a widely accepted procedure for stroke prevention, and carotid clamping is a necessary surgical step. Glutathionylated haemoglobin (HbSSG) has been recently employed as a biomarker of oxidative stress, its level being increased under several conditions, including hypoxia. This study aims to evaluating whether HbSSG level in ...
Shimizu Hideyuki H Department of Cardiovascular Surgery, Keio University, Shinjuku-ku, Tokyo, Japan. - - 2013
Aortic arch disease can be treated with hybrid repair (extra-anatomic bypass plus placement of aortic endoprostheses), but there is controversy about whether a bypass from one relatively small vessel will provide adequate blood flow to the entire brachiocephalic system. We, therefore, compared flow volumes before and after hybrid repair. We ...
Goode Stephen D - - 2013
PURPOSE: To assess the effectiveness of flow reversal as an alternative means of cerebral protection by using transcranial Doppler recordings and diffusion-weighted imaging (DWI) as surrogate markers of brain injury. MATERIALS AND METHODS: Eighteen patients with symptomatic carotid artery disease were recruited. Magnetic resonance imaging was performed before the intervention ...
Harloff A - - 2013
BACKGROUND AND PURPOSE:4D flow MR imaging is an emerging technique that allows visualization and quantification of 3D blood flow in vivo. However, representative studies evaluating its accuracy are lacking. Therefore, we compared blood flow quantification by using 4D flow MR imaging with US within the carotid bifurcation.MATERIALS AND METHODS:Thirty-two healthy ...
Pennekamp Claire Wa - - 2013
ABSTRACT: BACKGROUND: Intraoperative arterial hypotension can lead to severe complications in patients undergoing carotid endarterectomy, in particular if cerebral auto-regulation is impaired. Short-acting agents, such as phenylephrine or ephedrine, commonly used to correct intra-operative hypotension, have different hemodynamic effects. Recently, it was reported that, in healthy anesthetized subjects with intact ...
Saeed Nazia Parveen - - 2013
Temporal insonation is not always possible for the middle cerebral artery (MCA) for blood flow velocity (BFV) measurements, to estimate cerebral autoregulation. We compared BFV and cerebral autoregulation estimates from the common-carotid (CCA) and internal-carotid arteries (ICA) with the MCA. BFV was measured at the CCA, ICA and MCA, synchronously ...
Ozdemir Ozcan - - 2013
OBJECTIVE: Cardiac resynchronisation therapy (CRT) has emerged as a new treatment strategy for a subgroup of patients with heart failure. In this study, we aimed to evaluate acute effects of CRT on cerebral blood flow. MATERIAL AND METHODS: Twenty-two (six female and 16 male) patients (mean age 60.8±5.3 years) with ...
Yang Fuwei - - 2013
Complications due to brain edema and breakdown of blood brain barrier are an important factor affecting the treatment effects of patients with severe carotid stenosis. In this study, we investigated the protective effects of ischemic postconditioning on brain edema and disruption of blood brain barrier via establishing rat model of ...
Huang Tzung-Chi - - 2013
We analyzed intracranial regional blood flows using an optical flow method (OFM) and digital subtraction angiography in patients with internal carotid artery (ICA) stenosis. We also retrospectively explored the correlation between the patients' diagnoses and the severity of the ICA stenoses. OFM, an image-processing algorithm to estimate motion, was applied ...
Nagatani Kimihiro - - 2013
In recent studies, molecular hydrogen selectively reduced the levels of hydroxyl radicals in vitro and exerted a therapeutic anti-oxidant activity in a rat middle cerebral artery occlusion model. The aim of this study was to investigate the effect of hydrogen gas on a mouse bilateral common carotid artery occlusion (BCCAO) ...
Scott Jason A JA Department of Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, United States of - - 2013
Sustained hemodynamic stress mediated by high blood flow promotes arteriogenesis, the outward remodeling of existing arteries. Here, we examined whether Ca²⁺/calmodulin-dependent kinase II (CaMKII) regulates arteriogenesis. Ligation of the left common carotid led to an increase in vessel diameter and perimeter of internal and external elastic lamina in the contralateral, ...
Pennekamp C W A - - 2012
The benefit of carotid revascularization is hampered by occurrence of periprocedural cerebrovascular complications. Cerebral hyperperfusion syndrome (CHS) is a potentially life threatening complication occurring in approximately 3% of all patients following either carotid endarterectomy (CEA) or carotid angioplasty with stenting (CAS). CHS generally is defined as a transcranial Doppler (TCD) ...
Pennekamp C W A - - 2012
The benefit of carotid revascularization is hampered by occurrence of periprocedural cerebrovascular complications. Cerebral hyperperfusion syndrome (CHS) is a potentially life threatening complication occurring in approximately 3% of all patients following either carotid endarterectomy (CEA) or carotid angioplasty with stenting (CAS). CHS generally is defined as a transcranial Doppler (TCD) ...
Su Yi Y Department of Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO, USA. - - 2013
Positron emission tomography (PET) with (15)O-labeled water can provide reliable measurement of cerebral blood flow (CBF). Quantification of CBF requires knowledge of the arterial input function (AIF), which is usually provided by arterial blood sampling. However, arterial sampling is invasive. Moreover, the blood generally is sampled at the wrist, which ...
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