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Sample records for temporal artery wall

  1. Higher magnification microsurgical repair of donor artery dissection in superficial temporal artery to middle cerebral artery anastomosis--technical note.

    Science.gov (United States)

    Matsumura, Nobuhisa; Shibata, Takashi; Kamiyama, Hironaga; Tomita, Takahiro; Okamoto, Soushi; Kubo, Michiya; Horie, Yukio

    2011-01-01

    Donor artery dissection is a known cause of technical failure in microvascular anastomosis. A method for detection and direct repair of donor artery dissection before superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis is described using a high magnification operating microscope (maximum 50.4× magnification). Before STA-MCA anastomosis, the stump of the STA is stained using methylrosaniline chloride (pyoctaninum blue) and is observed under higher magnifications. Microsurgical suturing of the arterial dissection is performed before the anastomosis procedure under the high magnification microscope. This method was used in two patients with symptomatic hemodynamic cerebrovascular occlusive disease. Postoperative angiography revealed good patency and no complications occurred. This method may be useful for detection and direct repair of arterial dissection in small vessel walls before STA-MCA anastomosis.

  2. Arterial wall elasticity: state of the art and future prospects.

    Science.gov (United States)

    Messas, E; Pernot, M; Couade, M

    2013-05-01

    Peripheral vascular disease is a frequently occurring disease and is most often caused by atherosclerosis and more rarely by anomalies of the collagen or other components of the arterial wall. Arterial stiffness problems form one of the precursor phenomena of peripheral vascular disease, and in the case of atherosclerosis represents an independent risk marker for the occurrence of cardiovascular disease. The first techniques, developed to evaluate arterial stiffness, use indirect measurements such as pulse wave velocity or the analysis of variations in pressure and volume to estimate arterial wall stiffness. Techniques based on the pulse wave lack precision because they assume that arterial stiffness is uniform throughout the path of the pulse wave, and that it is constant throughout the cardiac cycle. Moreover, measuring the velocity of the pulse wave may be less precise in certain pathological situations: metabolic syndrome, obesity, large chest, mega-dolico artery. Techniques based on the analysis of variations in pressure and in volume do not accurately measure blood pressure, which can only be taken externally. In addition, these techniques require dedicated equipment, which is not reimbursed by the French health care system, and which is cumbersome to use (especially for techniques based on variation in pressure) in clinical practice. This explains why these two techniques are not used in clinical practice. Ultrafast echography is a new ultrasound imaging method that can record up to 10,000 images per second. This high temporal resolution makes it possible to measure the velocity of the local pulse wave and arterial wall stiffness thanks to the remote palpation carried out by shear wave. The ease of use and the accuracy of these two techniques suggest that these diagnostic applications will play a significant role in vascular pathology in the future. It is possible in real time, using a traditional vascular ultrasound probe, to make an accurate assessment of

  3. Temporal analysis of regional wall motion from cine cardiac MRI

    Science.gov (United States)

    Ratib, Osman M.; Didier, Dominique; Chretien, Anne; Rosset, Antoine; Magnin, Isabelle E.; Ligier, Yves

    1996-04-01

    views was calculated and used to identify regions with asynchronous wall motion in patients with coronary artery disease. Results suggest that this technique is more sensitive than global functional parameters such as ejection fraction for the detection of ventricular dysfunction. Color coded parametric display offers a more convenient way for the identification and localization of regional wall motion asynchrony. Data obtained from endocardial wall motion analysis were not significantly different from wall thickening measurements. The innovative approach of evaluating the temporal behavior of regional wall motion anomalies is expected to provide clinically relevant data about subtle alteration that cannot be detected through simple analysis of the extent (amplitude) of wall motion or myocardial thickening. Temporal analysis of regional WM abnormality from cine MRI offers an innovative and promising means for objective quantitative evaluation of subtle regional abnormalities. Color coded parametric maps allowed a better identification and localization of regional WM asynchrony.

  4. Effect of elasticity on wall shear stress inside cerebral aneurysm at anterior cerebral artery.

    Science.gov (United States)

    Xu, Lijian; Sugawara, Michiko; Tanaka, Gaku; Ohta, Makoto; Liu, Hao; Yamaguchi, Ryuhei

    2016-05-18

    Many numerical studies have been published with respect to about flow structures around cerebral aneurysm assuming to be rigid. Furthermore, there is little experimental research concerning aneurysm with elastic wall. Wall shear stress in elastic wall comparing with rigid wall should be clarified in experimental approach and verified in CFD. We have experimentally realized elastic aneurysm model accompanying with wall deformation. Wall shear stress was examined for both rigid and elastic aneurysm models in pulsatile flow. Effect of elasticity on wall shear stress inside aneurysm induced at the apex of anterior cerebral artery was experimentally examined by particle image velocimetry in vitro. In order to adjust the wall deformation, the pressure adjustment chamber was specially equipped outside the aneurysm wall. Effect of elasticity on wall shear stress was noticed on the comparison with that of rigidity. Wall elasticity reduced the peak magnitude, the spatial and temporal averaged wall shear stress comparing with those of wall rigidity experimentally. These reductions were endorsed by fluid-structure interaction simulation. Elastic wall comparing with rigid wall would reduce the peak magnitude, the spatial and temporal averaged wall shear stress acting on vascular wall.

  5. Arterial Wall Properties and Womersley Flow in Fabry Disease

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    Dimitriadis Emilios

    2002-01-01

    Full Text Available Abstract Background Fabry disease is an X-linked recessive lysosomal storage disease resulting in the cellular accumulation of globotriaosylceramide particularly globotriaosylceramide. The disease is characterized by a dilated vasculopathy with arterial ectasia in muscular arteries and arterioles. Previous venous plethysomographic studies suggest enhanced endothelium-dependent vasodilation in Fabry disease indicating a functional abnormality of resistance vessels. Methods We examined the mechanical properties of the radial artery in Fabry disease, a typical fibro-muscular artery. Eight control subjects and seven patients with Fabry disease had a right brachial arterial line placed allowing real time recording of intra-arterial blood pressure. Real time B-mode ultrasound recordings of the right radial artery were obtained simultaneously allowing calculation of the vessel wall internal and external diameter, the incremental Young's modulus and arterial wall thickness. By simultaneously measurement of the distal index finger-pulse oximetry the pulse wave speed was calculated. From the wave speed and the internal radial artery diameter the volume flow was calculated by Womersley analysis following truncation of the late diastolic phase. Results No significant difference was found between Fabry patients and controls for internal or external arterial diameters, the incremental Young's modulus, the arterial wall thickness, the pulse wave speed and the basal radial artery blood flow. Further, no significant difference was found for the radial artery blood flow in response to intra-arterial acetylcholine or sodium nitroprusside. Both drugs however, elevated the mean arterial flow. Conclusions The current study suggests that no structural or mechanical abnormality exists in the vessel wall of fibro-muscular arteries in Fabry disease. This may indicate that a functional abnormality downstream to the conductance vessels is the dominant feature in

  6. Impact of exercise training on arterial wall thickness in humans.

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    Thijssen, Dick H J; Cable, N Timothy; Green, Daniel J

    2012-04-01

    Thickening of the carotid artery wall has been adopted as a surrogate marker of pre-clinical atherosclerosis, which is strongly related to increased cardiovascular risk. The cardioprotective effects of exercise training, including direct effects on vascular function and lumen dimension, have been consistently reported in asymptomatic subjects and those with cardiovascular risk factors and diseases. In the present review, we summarize evidence pertaining to the impact of exercise and physical activity on arterial wall remodelling of the carotid artery and peripheral arteries in the upper and lower limbs. We consider the potential role of exercise intensity, duration and modality in the context of putative mechanisms involved in wall remodelling, including haemodynamic forces. Finally, we discuss the impact of exercise training in terms of primary prevention of wall thickening in healthy subjects and remodelling of arteries in subjects with existing cardiovascular disease and risk factors.

  7. Experimental and numerical studies of two arterial wall delamination modes.

    Science.gov (United States)

    Leng, Xiaochang; Zhou, Boran; Deng, Xiaomin; Davis, Lindsey; Lessner, Susan M; Sutton, Michael A; Shazly, Tarek

    2017-09-19

    Arterial wall dissection, which results from various pathophysiological processes, can lead to the occurrence of large area delamination in the aortic wall that can potentially block blood flow and lead to deleterious clinical conditions. Despite its critical clinical relevance, few studies have focused on investigating the failure mode of delamination in the arterial wall. In this study, we quantify the energy release rate of the medial layer of a porcine abdominal aorta via two delamination experiments: the mixed-mode delamination experiment and the "T"-shaped delamination experiment. A cohesive zone model (CZM) is applied to simulate the arterial wall delamination and Holzapfel-Gasser-Ogden (HGO) material model is used to capture the bulk arterial material behavior. A set of parameter values for the HGO and CZM models are identified through matching simulation predictions of the load vs. load-point displacement curve with experimental measurements. Then the parameter values and critical energy release rates obtained from experiments are used as input data for simulation predictions for two arterial wall delamination experiments. The simulation predictions show that the delamination front matches well with experimental measurements. Moreover, the mixed-mode delamination experiment reveals a shear mode-dominated failure event, whereas the "T"-shaped delamination experiment is an opening failure process. The integration of experimental data and numerical predictions of arterial delamination events provides a comprehensive description of distinct failure modes and aids in the prediction of aortic dissection. Copyright © 2017. Published by Elsevier Ltd.

  8. Sonographic assessment of splanchnic arteries and the bowel wall

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    Dietrich, C.F. [Medical Department II, Caritas-Krankenhaus, Uhlandstr. 7, D-97980 Bad Mergentheim (Germany)], E-mail: Christoph.dietrich@ckbm.de; Jedrzejczyk, M.; Ignee, A. [Medical Department II, Caritas-Krankenhaus, Uhlandstr. 7, D-97980 Bad Mergentheim (Germany)

    2007-11-15

    The intestinal wall can be visualized using high resolution transabdominal ultrasound. The normal intestinal wall thickness in the terminal ileum, cecum, and right and left colon is <2 mm when examined with graded compression. It is important to appreciate that a contracted intestinal segment can be misinterpreted as a thickened wall. Vascularisation can be mainly displayed in the second hyperechoic layer (submucosal layer) as well as vessels penetrating the muscularis propria. Imaging of the gastrointestinal wall is dependent on the experience of the examiner as well dependent on the equipment used. Acute or chronic inflammation of the intestinal wall is accompanied by increased perfusion of the mesentery, which can be displayed non-quantitatively with colour duplex. In contrast, ischemia is characterised by hypoperfusion of the mesenteric arteries and the bowel wall. The most promising sonographic approach in assessing splanchnic arteries and the bowel wall is combining the analysis of superior and inferior mesenteric inflow by pulsed Doppler scanning (systolic and diastolic velocities, resistance index) with the end-organ vascularity by colour Doppler imaging diminishing the influence of examination technique only displaying bowel wall vascularity. Colour Doppler imaging has been described as helpful in a variety of gastrointestinal disorders, particularly in patients with Crohn's disease, celiac disease, mesenteric artery stenosis and other ischemic gastrointestinal diseases, graft versus host disease and hemorrhagic segmental colitis.

  9. Traumatic aneurysm of the superficial temporal artery: case report.

    Science.gov (United States)

    Fox, J T; Cordts, P R; Gwinn, B C

    1994-04-01

    Traumatic aneurysms of the temporal artery are uncommon, with less than 200 cases reported in the literature. A case resulting from a head injury from playing a popular new survival game known as "paintball" is presented here. A general review of the literature on traumatic temporal artery aneurysms is provided, as well as information on this new form of recreation and safety recommendations for "paintball" players.

  10. DEFORMATION OF THE WALL OF THE ARTERY WITH TIME ...

    African Journals Online (AJOL)

    Investigation has been carried out to see how the presence of a growing stenosis affects the deformation of the wall of an artery in the pulsatile flow of blood. The expressions for the resulting deformations in the radial and axial directions were obtained. From analysis of these results, we noted that at the beginning of the ...

  11. Impact of exercise training on arterial wall thickness in humans.

    NARCIS (Netherlands)

    Thijssen, D.H.J.; Cable, N.T.; Green, D.J.

    2012-01-01

    Thickening of the carotid artery wall has been adopted as a surrogate marker of pre-clinical atherosclerosis, which is strongly related to increased cardiovascular risk. The cardioprotective effects of exercise training, including direct effects on vascular function and lumen dimension, have been

  12. Leukoaraiosis is associated with arterial wall thickness: a quantitative analysis.

    Science.gov (United States)

    Auriel, Eitan; Csiba, Laszlo; Berenyi, Ervin; Varkonyi, Ildiko; Mehes, Gabor; Kardos, Laszlo; Karni, Arnon; Bornstein, Natan M

    2012-06-01

    Leukoaraiosis refers to an age-related, abnormal appearance of the brain white matter on neuroimaging. The association between leukoaraiosis and cerebrovascular disease suggests that ischemia may be an important contributing factor; however, the pathogenesis of the condition remains controversial. We hypothesized that physical abnormalities of blood vessels might be culpable and compared the external and internal measurements of blood vessel walls between brains that demonstrated leukoaraiosis on imaging and normal control brains. Fourteen brains of individuals who had been diagnosed as having severe leukoaraiosis and five non-leukoaraiosis control brains were studied. Arterial cross-sections were evaluated by length measurements with an image analysis device. Arterial wall thickness and the ratio of the outer and inner diameters of the vessel were measured. We measured a total of 108 vessels in the leukoaraiosis group and 95 vessels in the control group. The vessel walls of the leukoaraiosis patients were an average of 5.5 µm thicker than the walls of control vessels of the same inside diameter (P = 0.0000, 95% CI 3.01-8.08) and an average of 2.3 µm thicker than walls of control vessels of the same outside diameter (P = 0.016, 95% CI 0.48-4.17). Our data provide evidence that leukoaraiosis is associated with vessel wall thickening in an additive fashion and indicate that structural vascular abnormalities are associated with leukoaraiosis. © 2011 Japanese Society of Neuropathology.

  13. Automatic airway-artery analysis on lung CT to quantify airway wall thickening and bronchiectasis

    DEFF Research Database (Denmark)

    Perez-Rovira, Adria; Kuo, Wieying; Petersen, Jens

    2016-01-01

    Purpose: Bronchiectasis and airway wall thickening are commonly assessed in computed tomography (CT) by comparing the airway size with the size of the accompanying artery. Thus, in order to automate the quantification of bronchiectasis and wall thickening following a similar principle......, and pairs airway branches with the accompanying artery, then quantifies airway wall thickening and bronchiectasis by measuring the wall-artery ratio (WAR) and lumen and outer wall airway-artery ratio (AAR). Measurements that do not use the artery size for normalization are also extracted, including wall......-consuming manual annotations and visual scoring methods to quantify abnormal widening and thickening of airways....

  14. Occipital artery to middle cerebral artery bypass in cases of unavailable superficial temporal artery.

    Science.gov (United States)

    Hirano, Tsukasa; Mikami, Takeshi; Suzuki, Hime; Hirano, Toru; Kimura, Yusuke; Komatsu, Katusya; Akiyama, Yukinori; Wanibuchi, Masahiko; Mikuni, Nobuhiro

    2018-01-22

    In neurosurgery, extracranial-to-intracranial (EC-IC) bypass surgery is necessary for patients who have undergone surgery in which the superficial temporal artery (STA) was already used for a different bypass procedure or was damaged. Here, we report our experience with EC-IC bypass using the occipital artery (OA) in cases in which the STA is unavailable, and discuss the technical considerations and pitfalls. Five patients with ischemic-onset moyamoya disease and atherosclerotic disease were included. Two patterns of skin incisions were planned according to the OA pathway and recipient artery location. In one method, a skin incision is made above the OA and a craniotomy is performed under this incision after OA dissection. In the other method, a skin incision is made above the OA to enable its dissection and a craniotomy is performed via a separate skin incision. No major perioperative complications developed in any of the five cases, and bypass patency was confirmed in all patients. There was a significant difference between the pre- and postoperative asymmetry ratio of the mean transit time values. OA-to- middle cerebral artery (MCA) bypass is a simple and effective method in patients in whom the STA was already used or was damaged by previous intracranial revascularization or a craniotomy. This procedure could be an alternative to STA-MCA bypass in patients without an available STA. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Wall shear stress evolution in carotid artery bifurcation

    Science.gov (United States)

    Bernad, S. I.; Bosioc, A. I.; Totorean, A. F.; Petre, I.; Bernad, E. S.

    2017-07-01

    The steady flow in an anatomically realistic human carotid bifurcation was simulated numerically. Main parameters such as wall shear stress (WSS), velocity profiles and pressure distributions are investigated in the carotid artery, namely in bifurcation and sinusoidal enlargement regions. Flow in the carotid sinus is dominated by a single secondary vortex motion accompanied by a strong helical flow. This type of flow is induced primarily by the curvature and asymmetry of the in vivo geometry. Low wall shear stress concentration occurs at both the anterior and posterior aspects of the proximal internal bulb.

  16. Constitutive modelling of an arterial wall supported by microscopic measurements

    Directory of Open Access Journals (Sweden)

    Vychytil J.

    2012-06-01

    Full Text Available An idealized model of an arterial wall is proposed as a two-layer system. Distinct mechanical response of each layer is taken into account considering two types of strain energy functions in the hyperelasticity framework. The outer layer, considered as a fibre-reinforced composite, is modelled using the structural model of Holzapfel. The inner layer, on the other hand, is represented by a two-scale model mimicing smooth muscle tissue. For this model, material parameters such as shape, volume fraction and orientation of smooth muscle cells are determined using the microscopic measurements. The resulting model of an arterial ring is stretched axially and loaded with inner pressure to simulate the mechanical response of a porcine arterial segment during inflation and axial stretching. Good agreement of the model prediction with experimental data is promising for further progress.

  17. Wall morphology, blood flow and wall shear stress: MR findings in patients with peripheral artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Galizia, Mauricio S.; Barker, Alex; Collins, Jeremy; Carr, James [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Liao, Yihua [Northwestern University' s Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL (United States); McDermott, Mary M. [Northwestern University' s Feinberg School of Medicine, Department of Preventive Medicine, Chicago, IL (United States); Northwestern University' s Feinberg School of Medicine, Department of Medicine, Chicago, IL (United States); Markl, Michael [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Northwestern University, Department Biomedical Engineering, McCormick School of Engineering, Chicago, IL (United States)

    2014-04-15

    To investigate the influence of atherosclerotic plaques on femoral haemodynamics assessed by two-dimensional (2D) phase-contrast (PC) magnetic resonance imaging (MRI) with three-directional velocity encoding. During 1 year, patients with peripheral artery disease and an ankle brachial index <1.00 were enrolled. After institutional review board approval and written informed consent, 44 patients (age, 70 ± 12 years) underwent common femoral artery MRI. Patients with contra-indications for MRI were excluded. Sequences included 2D time-of-flight, proton-density, T1-weighted and T2-weighted MRI. Electrocardiogram (ECG)-gated 2D PC-MRI with 3D velocity encoding was acquired. A radiologist classified images in five categories. Blood flow, velocity and wall shear stress (WSS) along the vessel circumference were quantified from the PC-MRI data. The acquired images were of good quality for interpretation. There were no image quality problems related to poor ECG-gating or slice positioning. Velocities, oscillatory shear stress and total flow were similar between patients with normal arteries and wall thickening/plaque. Patients with plaques demonstrated regionally increased peak systolic WSS and enhanced WSS eccentricity. Combined multi-contrast morphological imaging of the peripheral arterial wall with PC-MRI with three-directional velocity encoding is a feasible technique. Further study is needed to determine whether flow is an appropriate marker for altered endothelial cell function, vascular remodelling and plaque progression. (orig.)

  18. Effects of wall condition on flow distributions in arterial modeling: comparison of rigid, dynamic, and compliant walls

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    He, Fan [Beijing University of Civil Engineering and Architecture, Beijing (China); Hua, Lu; Gao, Li jian [Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

    2016-03-15

    Blood flow distributions were evaluated using various computational strategies. Three commonly used wall conditions in arterial modeling were employed, namely rigid, dynamic and compliant walls. The results show that the velocity distributions are similar under rigid and dynamic walls, developing into the Poiseuille flow, but they are blunt under compliant walls. The peak pressure under rigid walls is highest, but the model of dynamic walls has a good approximation of pressure against the model of compliant walls. The results indicate that a model of compliant walls appears to be a computationally and reasonably accurate approximation of blood velocity distributions compared with the analysis under rigid or dynamic walls. Introducing fluid-structure interaction into arterial modeling is necessary to ensure reliable results and information. However, a model of dynamic walls seems to be a computationally inexpensive yet reasonably accurate approximation for pressure.

  19. Linear and nonlinear viscoelastic arterial wall models: application on animals

    CERN Document Server

    Ghigo, Arthur; Armentano, Ricardo; Lagrée, Pierre-Yves; Fullana, Jose-Maria

    2016-01-01

    This work deals with the viscoelasticity of the arterial wall and its influence on the pulse waves. We describe the viscoelasticity by a non-linear Kelvin-Voigt model in which the coefficients are fitted using experimental time series of pressure and radius measured on a sheep's arterial network. We obtained a good agreement between the results of the nonlinear Kelvin-Voigt model and the experimental measurements. We found that the viscoelastic relaxation time-defined by the ratio between the viscoelastic coefficient and the Young's modulus-is nearly constant throughout the network. Therefore, as it is well known that smaller arteries are stiffer, the viscoelastic coefficient rises when approaching the peripheral sites to compensate the rise of the Young's modulus, resulting in a higher damping effect. We incorporated the fitted viscoelastic coefficients in a nonlinear 1D fluid model to compute the pulse waves in the network. The damping effect of viscoelasticity on the high frequency waves is clear especiall...

  20. Ultrasound settings significantly alter arterial lumen and wall thickness measurements

    Directory of Open Access Journals (Sweden)

    Green Daniel J

    2008-01-01

    Full Text Available Abstract Background Flow-mediated dilation (FMD and carotid intima-medial thickness (CIMT, measured by ultrasound, are widely used to test the efficacy of cardioprotective interventions. Although assessment methods vary, automated edge-detecting image analysis software is routinely used to measure changes in FMD and CIMT. We aimed to quantify the effect that commonly adjusted ultrasound settings have on arterial lumen and wall thickness measurements made with CIMT measurement software. Methods We constructed phantom arteries from a tissue-mimicking agar compound and scanned them in a water bath with a 10 MHz multi-frequency linear-array probe attached to a high-resolution ultrasound machine. B-mode images of the phantoms were recorded with dynamic range (DR and gain set at five decibel (dB increments from 40 dB to 60 dB and -10 dB to +10 dB respectively. Lumen diameter and wall-thickness were measured off-line using CIMT measurement software. Results Lumen measurements: there was a strong linear relationship between DR and gain and measured lumen diameter. For a given gain level, a 5 dB increase in DR reduced the measured lumen diameter by 0.02 ± 0.004 mm (p CIMT measurements: For a fixed gain level, a 5 dB increase in DR increased measured wall thickness by 0.003 ± 0.002 mm (p Conclusion DR, gain and probe distance significantly alter lumen diameter and CIMT measurements made using image analysis software. When CIMT and FMD are used to test the efficacy of cardioprotective interventions, the DR, gain and probe position used to record baseline scans should be documented and replicated in post-treatment scans in individual trial subjects. If more than one sonographer or imaging centre is used to collect data, the study protocol should document specific DR and gain settings to be used in all subjects.

  1. The resonance theory of coronary arterial wall stress as an explanation for the distribution of coronary artery disease.

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    John, Lindsay C H

    2010-05-01

    The coronary arteries are unique within the arterial system in being subject to a continuous oscillatory displacement. It is hypothesised that oscillatory resonance of the coronary arteries occurs when the heart rate is the same as the arteries' Natural Frequency of oscillation. If resonance were to occur then standing waves would exist along the coronary arteries. The sites of the anti-nodes of such standing waves would be the sites of increased wall stress and therefore be expected to be predisposed to disease. Coronary artery resonance would explain the observed increased incidence of disease in the proximal segments of the arteries. It is proposed that coronary artery resonance is a previously unrecognised aetiological factor for coronary artery disease that contributes to its location. If the hypothesis is true then there are potential important consequences for the diagnosis and treatment of the disease.

  2. Atomic Force Microscopy Study of Atherosclerosis Progression in Arterial Walls.

    Science.gov (United States)

    Timashev, Peter S; Kotova, Svetlana L; Belkova, Galina V; Gubar'kova, Ekaterina V; Timofeeva, Lidia B; Gladkova, Natalia D; Solovieva, Anna B

    2016-04-01

    Cardiovascular disease remains the leading cause of mortality worldwide. Here we suggest a novel approach for tracking atherosclerosis progression based on the use of atomic force microscopy (AFM). Using AFM, we studied cross-sections of coronary arteries with the following types of lesions: Type II-thickened intima; Type III-thickened intima with a lipid streak; Type IV-fibrotic layer over a lipid core; Type Va-unstable fibrotic layer over a lipid core; Type Vc-very thick fibrotic layer. AFM imaging revealed that the fibrotic layer of an atherosclerotic plaque is represented by a basket-weave network of collagen fibers and a subscale network of fibrils that become looser with atherosclerosis progression. In an unstable plaque (Type Va), packing of the collagen fibers and fibrils becomes even less uniform than that at the previous stages, while a stable fibrotic plaque (Vc) has significantly tighter packing. Such alterations of the collagen network morphology apparently, led to deterioration of the Type Va plaque mechanical properties, that, in turn, resulted in its instability and propensity to rupture. Thus, AFM may serve as a useful tool for tracking atherosclerosis progression in the arterial wall tissue.

  3. Incidental internal carotid artery calcifications on temporal bone CT in children

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    Koch, Bernadette; Jones, Blaise [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Blackham, Aaron [University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2007-02-15

    Incidental internal carotid artery (ICA) calcifications are occasionally noted on CT images of the brain and temporal bone. In adults, incidental calcifications have been correlated with increased incidence of hypercholesterolemia, cardiac disease, diabetes and carotid stenosis. To determine the incidence of incidental calcifications of the carotid siphon on temporal bone CT in children. We retrospectively reviewed 24 months of consecutive temporal bone CT examinations in children aged 18 years and younger. CT examinations on 663 patients were reviewed and the presence or absence of ICA calcifications was ranked as absent, questionable or definitive. In patients in whom definitive calcifications were identified, hospital charts were reviewed for evidence of diabetes mellitus, hypercholesterolemia, hypertriglyceridemia, hyperlipidemia and chronic renal disease as potential causes of early atherosclerosis. Of the 663 patients, 25% had definitive calcifications within the wall of the ICA: 6% of children younger than 2 years and 28% of children 12-19 years of age. Incidentally noted ICA calcifications are a common finding on temporal bone CT in children, most likely a physiologic response to turbulent flow at natural bends in the artery rather than secondary to underlying disease predisposing to early atherosclerotic calcification. (orig.)

  4. Exercise-mediated changes in conduit artery wall thickness in humans: role of shear stress

    NARCIS (Netherlands)

    Thijssen, D.H.J.; Dawson, E.A.; Munckhof, I.C. van den; Tinken, T.M.; Drijver, E. den; Hopkins, N.; Cable, N.T.; Green, D.J.

    2011-01-01

    Episodic increases in shear stress have been proposed as a mechanism that induces training-induced adaptation in arterial wall remodeling in humans. To address this hypothesis in humans, we examined bilateral brachial artery wall thickness using high-resolution ultrasound in healthy men across an

  5. Calculation of arterial wall temperature in atherosclerotic arteries: effect of pulsatile flow, arterial geometry, and plaque structure

    Directory of Open Access Journals (Sweden)

    Kim Taehong

    2007-03-01

    Full Text Available Abstract Background This paper presents calculations of the temperature distribution in an atherosclerotic plaque experiencing an inflammatory process; it analyzes the presence of hot spots in the plaque region and their relationship to blood flow, arterial geometry, and inflammatory cell distribution. Determination of the plaque temperature has become an important topic because plaques showing a temperature inhomogeneity have a higher likelihood of rupture. As a result, monitoring plaque temperature and knowing the factors affecting it can help in the prevention of sudden rupture. Methods The transient temperature profile in inflamed atherosclerotic plaques is calculated by solving an energy equation and the Navier-Stokes equations in 2D idealized arterial models of a bending artery and an arterial bifurcation. For obtaining the numerical solution, the commercial package COMSOL 3.2 was used. The calculations correspond to a parametric study where arterial type and size, as well as plaque geometry and composition, are varied. These calculations are used to analyze the contribution of different factors affecting arterial wall temperature measurements. The main factors considered are the metabolic heat production of inflammatory cells, atherosclerotic plaque length lp, inflammatory cell layer length lmp, and inflammatory cell layer thickness dmp. Results The calculations indicate that the best location to perform the temperature measurement is at the back region of the plaque (0.5 ≤ l/lp ≤ 0.7. The location of the maximum temperature, or hot spot, at the plaque surface can move during the cardiac cycle depending on the arterial geometry and is a direct result of the blood flow pattern. For the bending artery, the hot spot moves 0.6 millimeters along the longitudinal direction; for the arterial bifurcation, the hot spot is concentrated at a single location due to the flow recirculation observed at both ends of the plaque. Focusing on the

  6. Progressive arterial wall stiffening in patients with increasing diastolic blood pressure.

    Science.gov (United States)

    van den Berkmortel, F W; van der Steen, M; Hoogenboom, H; Wollersheim, H; van Langen, H; Thien, T

    2001-10-01

    Hypertension is an established risk factor for cardiovascular disease. Risk factor patterns for various cardiovascular complications are different. We studied the relationship between increasing diastolic blood pressure and arterial wall dynamics of various peripheral arteries in hypertensives to increase insight in the variability of properties within the arterial tree. Eighty-six untreated hypertensives participated in this cross-sectional study. The study-population was divided into quartiles with increasing diastolic office blood pressure. Cross-sectional compliance and distensibility coefficients of the carotid and femoral arteries were determined, using a vessel wall movement detector system (Wall Track System). Diameters of both common carotid arteries enlarged (right: from 7.4 +/- 0.2 to 7.9 +/- 0.2 mm) while cross-sectional compliance (right: from 0.61 +/- 0.04 to 0.42 +/- 0.04 mm(2)/kPa) and distensibility coefficients (right: from 14.2 +/- 1.0 to 9.0 +/- 1.0 10(-3)/kPa) gradually dropped with increasing diastolic blood pressure. Cross-sectional compliance and diameter of the right common femoral artery remained unchanged while distensibility coefficient decreased although less gradually when compared with the carotid arteries. In untreated hypertensives gradual arterial wall stiffening of the carotid arteries occurred with increasing diastolic blood pressure. Gradual changes were less clear in the common femoral artery which points to the heterogeneity of the arterial tree.

  7. MRI displays involvement of the temporalis muscle and the deep temporal artery in patients with giant cell arteritis

    Energy Technology Data Exchange (ETDEWEB)

    Veldhoen, Simon; Bley, Thorsten A. [University Medical Center Wuerzburg, Department of Diagnostic and Interventional Radiology, Wuerzburg (Germany); Klink, Thorsten [Inselspital - University Medical Center Bern, Department of Diagnostic, Interventional and Pediatric Radiology, Bern (Switzerland); Geiger, Julia [University Medical Center Freiburg, Department of Diagnostic and Interventional Radiology, Freiburg (Germany); University Children' s Hospital Zuerich, Division of Radiology, Zuerich (Switzerland); Vaith, Peter; Glaser, Cornelia [University Medical Center Freiburg, Department of Rheumatology and Immunology, Freiburg (Germany); Ness, Thomas [University Medical Center Freiburg, Department of Ophthalmology, Freiburg (Germany); Duwendag, Dirk [University Medical Center Kiel, Department of Ophthalmology, Kiel (Germany); Both, Marcus [University Medical Center Kiel, Department of Diagnostic and Interventional Radiology, Kiel (Germany)

    2014-11-15

    To assess deep temporal artery and temporalis muscle involvement in patients with giant cell arteritis (GCA). Ninety-nine patients who received magnetic resonance imaging (MRI) and superficial temporal artery biopsy (TAB) were included in this study. Patients with positive TAB (n = 61) were defined as GCA patients, those with negative TAB (n = 38) as the GCA-negative reference group. Contrast-enhanced T1w-images were acquired utilizing 1.5 T and 3 T MRI. Two radiologists assessed the images. Mural contrast-hyperenhancement and wall thickening of the deep temporal artery and hyperenhancement of the muscle were defined as inflammation. MRI results were correlated with jaw claudication in 70 patients. The two observers found temporalis muscle involvement in 19.7 % (n = 12) and 21.3 % (n = 13) of GCA patients. It occurred bilaterally in 100 %. Specificities were 92/97 % and sensitivities were 20/21 %. Deep temporal artery involvement was found in 34.4 % (n = 21) and 49.2 % (n = 30) and occurred bilaterally in 80/90.5 %. Specificities were 84/95 % and sensitivities were 34/49 %. Both structures were affected simultaneously in 18/21.3 %. Jaw claudication correlated moderately with inflammation of the temporalis muscle (r = 0.31; p < 0.05) and the deep temporal artery (r = 0.38; p = 0.01). MRI visualizes changes in the temporalis muscle and the deep temporal artery in GCA. Moderate correlation of clinical symptoms with MRI results was observed. circle Approximately 20 % of GCA patients presented with temporalis muscle inflammation. (orig.)

  8. Mid-infrared pulsed laser ablation of the arterial wall. Mechanical origin of "acoustic" wall damage and its effect on wall healing

    NARCIS (Netherlands)

    van Erven, L.; van Leeuwen, T. G.; Post, M. J.; van der Veen, M. J.; Velema, E.; Borst, C.

    1992-01-01

    Pulsed mid-infrared lasers are an alternative to excimer lasers for transluminal angioplasty. The mid-infrared lasers, however, were reported to produce "acoustic" wall damage that might impair the immediate and long-term results. To study the immediate and long-term effects on the arterial wall,

  9. Exercise-mediated changes in conduit artery wall thickness in humans: role of shear stress.

    Science.gov (United States)

    Thijssen, Dick H J; Dawson, Ellen A; van den Munckhof, Inge C L; Tinken, Toni M; den Drijver, Evert; Hopkins, Nicola; Cable, N Timothy; Green, Daniel J

    2011-07-01

    Episodic increases in shear stress have been proposed as a mechanism that induces training-induced adaptation in arterial wall remodeling in humans. To address this hypothesis in humans, we examined bilateral brachial artery wall thickness using high-resolution ultrasound in healthy men across an 8-wk period of bilateral handgrip training. Unilaterally, shear rate was attenuated by cuff inflation around the forearm to 60 mmHg. Grip strength, forearm volume, and girth improved similarly between the limbs. Acute bouts of handgrip exercise increased shear rate (P < 0.005) in the noncuffed limb, whereas cuff inflation successfully decreased exercise-induced increases in shear. Brachial blood pressure responses similarly increased during exercise in both the cuffed and noncuffed limbs. Handgrip training had no effect on baseline brachial artery diameter, blood flow, or shear rate but significantly decreased brachial artery wall thickness after 6 and 8 wk (ANOVA, P < 0.001) and wall-to-lumen ratio after week 8 (ANOVA, P = 0.005). The magnitude of decrease in brachial artery wall thickness and wall-to-lumen ratio after exercise training was similar in the noncuffed and cuffed arms. These results suggest that exercise-induced changes in shear rate are not obligatory for arterial wall remodeling during a period of 8 wk of exercise training in healthy humans.

  10. Impact of age and sex on carotid and peripheral arterial wall thickness in humans.

    Science.gov (United States)

    van den Munckhof, I; Scholten, R; Cable, N T; Hopman, M T E; Green, D J; Thijssen, D H J

    2012-12-01

    Although previous studies have reported age-related wall thickening in carotid arteries, it is not clear whether this is a systemic phenomenon which is also apparent in peripheral conduit arteries or whether conduit wall thickness (WT) changes occur to a similar degree in men and women. To determine whether sex modifies the impact of ageing on WT or wall-to-lumen ratio (W:L) in atherosclerosis-prone (i.e. carotid artery, femoral, superficial femoral, popliteal artery) and atherosclerosis-resistant (i.e. brachial artery) conduit arteries. We included 30 young (23 ± 2 year; 15M : 15F) and 31 older (70 ± 5 year; 18M : 13F) healthy subjects. High-resolution ultrasound was used to measure diameter, WT and wall-to-lumen ratio (W/L) in all arteries. Older subjects had increased WT and W/L in the carotid, femoral, superficial femoral, popliteal and brachial arteries (all P < 0.05). Compared with women, men demonstrated larger diameter and WT (both P < 0.01) across all arteries. Sex did not impact upon age-related changes in WT or W/L (P = 0.39 and 0.43 respectively). Our data suggest that age-related wall thickening, evident in the carotid artery, is also apparent in the arteries of the upper and lower limbs. The impact of age on wall thickening did not differ between men and women. These data support the presence of systemic increases in WT and W/L with age in apparently healthy humans, independent of sex. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

  11. Stimulated release of tissue plasminogen activator from artery wall sympathetic nerves: implications for stress-associated wall damage.

    Science.gov (United States)

    Hao, Zhifang; Jiang, Xi; Sharafeih, Roshanak; Shen, Shujing; Hand, Arthur R; Cone, Robert E; O'Rourke, James

    2005-06-01

    Recurrent stress is clinically associated with early onset hypertension and coronary artery disease. A mechanism linking emotion to pathogenic remodeling of the artery wall has not been identified. Stress stimulates acute regulated release of tissue plasminogen activator (t-PA) into the circulation, which is presently attributed to the vascular endothelium. Sympathetic neurons also synthesize t-PA and axonally transport it to the arterial smooth muscle. Unlike release by the endothelium, a stress-stimulated sympathetic discharge would potentially accelerate degradation of the wall matrix by plasmin. To assess whether sympathetic axons are the principal source of acute stress-induced arterial release of t-PA, we compared the output from small densely innervated and large sparsely innervated isolated artery segments before and after sympathetic stimulation, and after ablations. Following phenylephrine infusion densely-innervated microvessels in uveal eyecups were released over 60-fold greater amounts of active t-PA per milligram than the sparsely innervated aorta; and ten-fold more than carotid artery segments. Mesenteric artery release was 4.8-fold greater than release by the carotid artery. In vivo, uveal release of t-PA increased more than three-fold within one minute following superior cervical sympathetic ganglion electrical stimulation, and after phenylephrine, or nicotine infusions of the anterior chamber. Circulating levels of t-PA fell 70% following chemical sympathectomy. We propose that sympathetic nerves are the primary source of stress-induced release of t-PA into and from the densely innervated resistance arteries and arterioles, where dysregulated plasmin-induced proteolysis could damage the wall matrix.

  12. Epithelioid hemangioendothelioma of the temporal artery presenting as temporal arteritis: Case report and literature review

    Directory of Open Access Journals (Sweden)

    Salem Alowami

    2009-07-01

    Full Text Available Hemangioendotheliomas are classified as epithelioid hemangioendothelioma(EHE, retiform hemangioendothelioma, composite hemanioendothelioma, Kaposiform hemangioendothelioma (with or without Kasabach-Merritt syndrome, and Spindle cell hemangioendothelioma. The latter two types of hemangioendotheliomas usually follow a benign course, in contrast to the other types of hemangioendotheliomas, which are considered as a low grade malignant sarcoma with unpredictable prognosis. EHE's are rare tumors, mostly described in organs particularly the lungs and liver. Though endothelial in origin, EHE's reported to originate from small sized arteries are extremely rare. We report a very rare case of EHE arising from the temporal artery showing a peculiar presentation.

  13. MRI in giant cell (temporal) arteritis; Magnetresonanztomografie der Arteriitis temporalis Horton

    Energy Technology Data Exchange (ETDEWEB)

    Bley, T.A.; Uhl, M.; Frydrychowicz, A.; Langer, M. [Uniklinik Freiburg (Germany). Roentgendiagnostik; Markl, M. [Uniklinik Freiburg (Germany). Roentgendiagnostik - Medizinische Physik

    2007-07-15

    Giant cell (temporal) arteritis is a diagnostic challenge. Blindness is a dreaded complication, especially if high-dose steroid treatment is delayed. With an optimized MR protocol, noninvasive diagnosis of giant cell arteritis is facilitated. Submillimeter in-plane resolution makes it possible to distinguish healthy segments from inflamed segments. The lumen and arterial wall can be depicted in high detail. Post-contrast high-resolution MRI visualizes the superficial cranial arteries bilaterally and simultaneously, allowing assessment of the cranial involvement pattern. In combination with MR angiography of the aortic arch and supra-aortic arteries, the extracranial involvement pattern can be demonstrated in a single comprehensive MR examination assessing the cranial, cervical and thoracic vasculature. Good diagnostic image quality can be achieved at 1.5 Tesla and at 3 Tesla. However, due to higher signal-to-noise ratios, image quality seems to be superior at 3 Tesla. Over the course of successful long-term treatment, MR signs of mural inflammation decrease significantly and eventually vanish entirely. In contrast to color-coded Duplex sonography, which is a comparatively cost-efficient imaging modality, acquisition of high-resolution MRI is almost independent of the investigator's expertise. Compared to positron emission tomography with 18F-fluoro-2-deoxy-D-glucose, which is a very sensitive whole-body screening tool for detecting extracranial involvement of large vessel vasculitis, MRI allows visualization and assessment of both the superficial cranial arteries in high detail and the extracranial large artery involvement in the same investigation. (orig.)

  14. Increased arterial wall stiffness limits flow volume in the lower extremities in type 2 diabetic patients.

    Science.gov (United States)

    Suzuki, E; Kashiwagi, A; Nishio, Y; Egawa, K; Shimizu, S; Maegawa, H; Haneda, M; Yasuda, H; Morikawa, S; Inubushi, T; Kikkawa, R

    2001-12-01

    To document an association between arterial wall stiffness and reduced flow volume in the lower-extremity arteries of diabetic patients. We recruited 60 consecutive type 2 diabetic patients who had no history or symptoms of peripheral arterial disease (PAD) in the lower extremities and normal ankle/brachial systolic blood pressure index at the time of the study (non-PAD group) and 20 age-matched nondiabetic subjects (control group). We used an automatic device to measure pulse wave velocity (PWV) in the lower extremities as an index of arterial wall stiffness. At the popliteal artery, we evaluated flow volume and the resistive index as an index of arterial resistance to blood flow using gated two-dimensional cine-mode phase-contrast magnetic resonance imaging. Consistent with previous reports, we confirmed that the non-PAD group had an abnormally higher PWV compared with that of the control group (P lower extremities of diabetic patients.

  15. Posterior auricular artery-middle cerebral artery bypass: a rare superficial temporal artery variant with well-developed posterior auricular artery-case report.

    Science.gov (United States)

    Tokugawa, Joji; Nakao, Yasuaki; Kudo, Kentaro; Iimura, Koji; Esaki, Takanori; Yamamoto, Takuji; Mori, Kentaro

    2014-01-01

    The posterior auricular artery (PAA) is one of the branches of the external carotid artery, but is usually too small for use as a donor artery for middle cerebral artery (MCA) territory revascularization. An extremely unusual case of PAA-MCA anastomosis was performed in a patient requiring MCA territory revascularization because the superficial temporal artery (STA) parietal branch was absent and the PAA was large enough. A 65-year-old man developed mild motor weakness in the right extremities caused by multiple small infarctions. Single photon emission computed tomography (CT) revealed deterioration of the vascular reserve capacity in the left MCA area. Cerebral angiography showed severe stenosis in the C2 portion of the left internal carotid artery, absence of the parietal branch of the left STA, and a well-developed PAA extending to the parietal area. The patient underwent STA (frontal branch)-MCA and PAA-MCA double anastomosis, and has suffered no stroke or transient ischemic attack. The STA with no bifurcation is known as a rare variation. The PAA also occurs with size variations but well-developed PAA is thought to be extremely rare. PAA can be used as a donor artery for MCA territory revascularization if the vessel size is suitable. Preoperative evaluation of the anatomy is mandatory for harvesting the arteries.

  16. Artery Wall Assessment Helps Predict Kidney Transplant Outcome.

    Directory of Open Access Journals (Sweden)

    Domingo Hernández

    Full Text Available Kidney transplant recipients have high cardiovascular risk, and vascular inflammation may play an important role. We explored whether the inflammatory state in the vessel wall was related to carotid intima-media thickness (c-IMT and patient survival following kidney transplantation.In this prospective observational cohort study we measured c-IMT and expression of proinflammatory cytokines and adhesion molecules in the inferior epigastric artery in 115 kidney transplant candidates. Another c-IMT measurement was done 1-year post-transplantation in 107. By stepwise multiple regression analysis we explored factors associated with baseline c-IMT and their changes over time. Multivariate Cox regression analysis was constructed to identify risk factors for mortality.A worse cardiovascular profile (older age, smoker, diabetic, carotid plaque, systolic blood pressure and vascular calcification and higher VCAM-1 levels were found in patients in the highest baseline c-IMT tertile, who also had a worse survival. Factors independently related to baseline c-IMT were age (β=0.369, P<0.0001, fasting glucose (β=0.168, P=0.045, smoking (β=0.228, P=0.003 and VCAM-1 levels (β=0.244, P=0.002. Independent factors associated with c-IMT measurement 1-year post-transplantation were baseline c-IMT (β=-0.677, P<0.0001, post-transplant diabetes (β=0.225, P=0.003 and triglycerides (β=0.302, P=0.023. Vascular VCAM-1 levels were associated with increased risk of mortality in bivariate and multivariate Cox regression. Notably, nearly 50% of patients showed an increase or maintenance of high c-IMT 1 year post-transplantation and these patients experienced a higher mortality (13 versus 3.5%; P=0.021.A worse cardiovascular profile and a higher vascular VCAM-1 protein levels at time of KT are related to subclinical atheromatosis. This could lead to a higher post-transplant mortality. Pre-transplant c IMT, post-transplant diabetes and triglycerides at 1-year post

  17. Effects of the three-dimensional residual stresses on the mechanical properties of arterial walls.

    Science.gov (United States)

    Zheng, Xianbing; Ren, Jiusheng

    2016-03-21

    Effects of the three-dimensional residual stresses on the mechanical properties of arterial walls are analyzed in this paper, based on the model which considered the bending and stretching both in the circumferential and axial directions of the three distinct arterial layers. Moreover, different constitutive models are proposed to quantify the nonlinear mechanics of the three distinct layers and the important constituents, i.e. elastin, collagen fibers and smooth muscle cells (SMCs), are all taken into account. The stress distributions and pressure-radius curves of the arterial wall are given in details. Results demonstrate that the maximum values of the circumferential stress and the corresponding stress gradient in the media under the mean arterial pressure are reduced significantly as a consequence of the SMCs. The bending in the axial direction of the media and the opening angle of the intima have an obvious impact on the mechanical behaviors of arterial walls. This study may not only develop the understanding of effects of the three-dimensional residual stresses on the arterial wall response, but also can increase the accuracy of the analyses for patient-specific studies used for the treatments of arterial diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Prevention of the Rerupture of Collateral Artery Aneurysms on the Ventricular Wall by Early Surgical Revascularization in Moyamoya Disease: Report of Two Cases and Review of the Literature.

    Science.gov (United States)

    Kanamori, Fumiaki; Takasu, Syuntaro; Ota, Shinji; Seki, Yukio

    2018-01-01

    Collateral artery aneurysms are a source of intracranial hemorrhage in moyamoya disease. Several reports have shown that surgical revascularization leads to the obliteration of collateral artery aneurysms. However, its effect on the prevention of rebleeding has not been established, and the optimal timing of the operation remains unclear. The purpose of the present study is to evaluate the effects of surgical revascularization and to investigate the optimal operation timing in patients with moyamoya disease who have ruptured collateral artery aneurysms on the ventricular wall. Two patients with moyamoya disease who presented with intraventricular hemorrhage caused by rupture of collateral artery aneurysms on the wall of the lateral ventricle are presented here. In both cases, the aneurysms reruptured approximately 1 month after the initial hemorrhage. Both patients successfully underwent superficial temporal artery-middle cerebral artery anastomosis combined with indirect bypass in the subacute stage. The aneurysms decreased with the development of collateral circulation through the direct bypasses, and rebleeding did not occur after the surgery. Because ruptured collateral artery aneurysms on the wall of the lateral ventricle in moyamoya disease are prone to rerupture within 1 month, surgical revascularization may be recommended as soon as the patients are stable and able to withstand the operation. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. A finite element study of balloon expandable stent for plaque and arterial wall vulnerability assessment

    Science.gov (United States)

    Karimi, Alireza; Navidbakhsh, Mahdi; Razaghi, Reza

    2014-07-01

    The stresses induced within plaque tissues and arterial layers during stent expansion inside an atherosclerotic artery can be exceeded from the yield stresses of those tissues and, consequently, lead to plaque or arterial layer rupture. The distribution and magnitude of the stresses in each component involved in stenting might be clearly different for different plaque types and different arterial layers. In this study, a nonlinear finite element simulation was employed to investigate the effect of plaque composition (calcified, cellular, and hypocellular) on the stresses induced in the arterial layers (intima, media, and adventitia) during implantation of a balloon expandable coronary stent into a stenosed artery. The atherosclerotic artery was assumed to consist of a plaque and normal/healthy arterial tissues on its outer side. The results indicated a significant influence of plaque types on the maximum stresses induced within the plaque wall and arterial layers during stenting but not when computing maximum stress on the stent. The stress on the stiffest calcified plaque wall was in the fracture level (2.38 MPa), whereas cellular and hypocellular plaques remain stable owing to less stress on their walls. Regardless of plaque types, the highest von Mises stresses were observed on the stiffest intima layer, whereas the lowest stresses were seen to be located in less stiff media layer. The computed stresses on the intima layer were found to be high enough to initiate a rupture in this stiff layer. These findings suggest a higher risk of arterial vascular injury for the intima layer, while a lower risk of arterial injury for the media and adventitia layers.

  20. Lateral abdominal wall hematoma as a rare complication after carotid artery stenting: a case report

    Directory of Open Access Journals (Sweden)

    Satomi Jyunichiro

    2009-11-01

    Full Text Available Abstract Abdominal wall hematoma is a rare and life-threatening complication after carotid artery stenting (CAS, but it can occur when activated clotting time is prolonged. We report a right lateral abdominal wall hematoma caused by rupture of the superficial circumflex iliac artery after CAS in a 72-year-old man with severe stenosis of the origin of the right internal carotid artery. We performed CAS for the targeted lesion while activated clotting time exceeded 300 seconds. After 2 hours, he complained of right lateral abdominal pain. Abdominal computed tomography revealed an extensive hematoma in the right lateral abdominal wall. Activated clotting time was 180 seconds at this point. Seven hours later, he developed hypotension and hemoglobin level dropped to 11.3 g/dl. Subsequent computed tomography showed enlargement of the hematoma. Emergent selective angiography of the external iliac artery revealed active bleeding from the right superficial circumflex iliac artery. Transcatheter arterial embolization with Gelfoam and microcoils was performed successfully. With more CAS procedures being performed, it is important for endovascular surgeons and radiologists to consider the possibility of abdominal wall hematoma in this situation.

  1. Lack of age-related increase in carotid artery wall viscosity in cardiorespiratory fit men.

    Science.gov (United States)

    Kawano, Hiroshi; Yamamoto, Kenta; Gando, Yuko; Tanimoto, Michiya; Murakami, Haruka; Ohmori, Yumi; Sanada, Kiyoshi; Tabata, Izumi; Higuchi, Mitsuru; Miyachi, Motohiko

    2013-12-01

    Age-related arterial stiffening and reduction of arterial elasticity are attenuated in individuals with high levels of cardiorespiratory fitness. Viscosity is another mechanical characteristic of the arterial wall; however, the effects of age and cardiorespiratory fitness have not been determined. We examined the associations among age, cardiorespiratory fitness and carotid arterial wall viscosity. A total of 111 healthy men, aged 25-39 years (young) and 40-64 years (middle-aged), were divided into either cardiorespiratory fit or unfit groups on the basis of peak oxygen uptake. The common carotid artery was measured noninvasively by tonometry and automatic tracking of B-mode images to obtain instantaneous pressure and diameter hysteresis loops, and we calculated the effective compliance, isobaric compliance and viscosity index. In the middle-aged men, the viscosity index was larger in the unfit group than in the fit group (2533 vs. 2018 mmHg·s/mm, respectively: Pviscosity index was increased with advancing age, but these parameters were unaffected by cardiorespiratory fitness level. These results suggest that the wall viscosity in the central artery is increased with advancing age and that the age-associated increase in wall viscosity may be attenuated in cardiorespiratory fit men.

  2. Remnant Cholesterol Elicits Arterial Wall Inflammation and a Multilevel Cellular Immune Response in Humans.

    Science.gov (United States)

    Bernelot Moens, Sophie J; Verweij, Simone L; Schnitzler, Johan G; Stiekema, Lotte C A; Bos, Merijn; Langsted, Anne; Kuijk, Carlijn; Bekkering, Siroon; Voermans, Carlijn; Verberne, Hein J; Nordestgaard, Børge G; Stroes, Erik S G; Kroon, Jeffrey

    2017-05-01

    Mendelian randomization studies revealed a causal role for remnant cholesterol in cardiovascular disease. Remnant particles accumulate in the arterial wall, potentially propagating local and systemic inflammation. We evaluated the impact of remnant cholesterol on arterial wall inflammation, circulating monocytes, and bone marrow in patients with familial dysbetalipoproteinemia (FD). Arterial wall inflammation and bone marrow activity were measured using 18 F-FDG PET/CT. Monocyte phenotype was assessed with flow cytometry. The correlation between remnant levels and hematopoietic activity was validated in the CGPS (Copenhagen General Population Study). We found a 1.2-fold increase of 18 F-FDG uptake in the arterial wall in patients with FD (n=17, age 60±8 years, remnant cholesterol: 3.26 [2.07-5.71]) compared with controls (n=17, age 61±8 years, remnant cholesterol 0.29 [0.27-0.40]; P cholesterol accumulates in human hematopoietic stem and progenitor cells coinciding with myeloid skewing. Patients with FD have increased arterial wall and cellular inflammation. These findings imply an important inflammatory component to the atherogenicity of remnant cholesterol, contributing to the increased cardiovascular disease risk in patients with FD. © 2017 American Heart Association, Inc.

  3. Impact of wall thickness on conduit artery function in humans: is there a "Folkow" effect?

    Science.gov (United States)

    Thijssen, Dick H J; Willems, Laura; van den Munckhof, Inge; Scholten, Ralph; Hopman, Maria T E; Dawson, Ellen A; Atkinson, Greg; Cable, N Timothy; Green, Daniel J

    2011-08-01

    Regional heterogeneity in wall architecture and thickness may be present between conduit arteries in the upper and lower limbs in humans. These differences in wall architecture may, in turn, influence vascular responsiveness. Folkow proposed in the 1950s that heterogeneity in wall-to-lumen ratio (W:L) could contribute to differences in vascular responsiveness, but this hypothesis has never been directly confirmed in vivo. Our first aim was to examine wall thickness and W:L across arteries in the lower (common and superficial femoral) and upper limbs (brachial and radial) of healthy men (n=35) using high resolution ultrasound. In a subgroup (n=20) we examined the relationship between W:L of these arteries, physiological (flow-mediated dilation, FMD) and pharmacological vasodilation (glyceryl trinitrate, GTN). Diameter and wall thickness differed significantly across all arteries (ANOVA P<0.001), with smaller arteries having a relatively larger wall thickness. Moreover, we found a significant correlation between W:L and the FMD-response (r=0.55, P<0.001), which remained significant after correcting for the eliciting shear stress (r=0.47, P<0.001), indicating that W:L/FMD relationship was not primarily related to the impact of diameter on the shear rate stimulus to FMD. W:L also correlated strongly with the GTN-response (r=0.56, P<0.001) across all arteries studied. These results indicate that regional heterogeneity exists in W:L within, but also between, limbs. More importantly, differences in W:L contribute to differences in vascular functional responses, reinforcing the conceptual proposal of Folkow, who suggested that arteries with larger W:L exhibit exaggerated responses to vasoactive stimuli. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. Determination of wall tension in cerebral artery aneurysms by numerical simulation

    DEFF Research Database (Denmark)

    Isaksen, J.G.; Bazilevs, Y.; Kvamsdal, T.

    2008-01-01

    BACKGROUND AND PURPOSE: Cerebral artery aneurysms rupture when wall tension exceeds the strength of the wall tissue. At present, risk-assessment of unruptured aneurysms does not include evaluation of the lesions shape, yet clinical experience suggests that this is of importance. We aimed to develop...... a computational model for simulation of fluid-structure interaction in cerebral aneurysms based on patient specific lesion geometry, with special emphasis on wall tension. METHODS: An advanced isogeometric fluid-structure analysis model incorporating flexible aneurysm wall based on patient specific computed...... tomography angiogram images was developed. Variables used in the simulation model were retrieved from a literature review. RESULTS: The simulation results exposed areas of high wall tension and wall displacement located where aneurysms usually rupture. CONCLUSIONS: We suggest that analyzing wall tension...

  5. Intraoperative Evaluation of Reverse Bypass Using a Naturally Formed "Bonnet" Superficial Temporal Artery: Technical Note.

    Science.gov (United States)

    Nagm, Alhusain; Horiuchi, Tetsuyoshi; Hasegawa, Takatoshi; Hongo, Kazuhiro

    2016-04-01

    In reverse bypass that used a naturally formed "bonnet" superficial temporal artery, intraoperative volume flow measurement quantifies flow augmentation after revascularization, confirms flow preservation, and identifies inadvertent vessel compromise. A 75-year-old man presented with transient ischemic attacks attributed to right internal carotid artery stenosis. He underwent successful reverse bypass via a naturally formed "bonnet" superficial temporal artery middle cerebral artery bypass. As the result of proper intraoperative volume flow evaluation, a successful reverse bypass was achieved. Modification of the intraoperative stroke risk and prediction of the long-term patency after reverse bypass can be achieved by meticulous intraoperative blood flow evaluation. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Anterior temporal artery tap to identify systemic interference using short-separation NIRS measurements

    DEFF Research Database (Denmark)

    Sood, Mehak; Jindal, Utkarsh; Chowdhury, Shubhajit Roy

    2015-01-01

    that are also affected by tDCS. An approach may be to use short optode separations to measure systemic hemodynamic fluctuations occurring in the superficial layers which can then be used as regressors to remove the systemic contamination. Here, we demonstrate that temporal artery tap may be used to better...... change in the mean rSO2 better correlated with the corresponding percent change in log-transformed mean-power of EEG within 0.5 Hz-11.25 Hz frequency band after removing the systemic contamination using the temporal artery tap method. Based on our findings, we propose that anterior temporal artery tap...

  7. Arterial wall function is associated with cognitive performance primarily in elderly with type 2 diabetes.

    Science.gov (United States)

    Ravona-Springer, Ramit; Haratz, Salo; Tanne, David; Schmeidler, James; Efrati, Shai; Rosendorff, Clive; Beeri, Michal Schnaider; Silverman, Jeremy M

    2015-01-01

    Regression analyses compared 41 type 2 diabetes (T2D) and 131 non-T2D cognitively normal elderly males on the associations of arterial wall function measures [large artery elasticity index (LAEI), small artery elasticity index (SAEI), systemic vascular resistance (SVR), and total vascular impedance (TVI)] with cognitive performance (memory, language, and executive functions), controlling for socio-demographic and cardiovascular factors. Higher LAEI and lower TVI were significantly associated with better executive functions performance in T2D but not in non-T2D subjects. Lower TVI was more associated with better language performance in T2D. Results suggest that arterial wall function is associated with cognition in T2D.

  8. The correspondence between coronary arterial wall strain and histology in a porcine model of atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Liang Yun; Zhu Hui; Friedman, Morton H [Department of Biomedical Engineering, Duke University, Durham, NC (United States)], E-mail: mhfriedm@duke.edu

    2009-09-21

    Atherosclerotic plaque rupture is the leading cause of mortality in cardiovascular disease. Intravascular ultrasound (IVUS) imaging is a powerful clinical technique that provides real-time cross-sectional images of the arterial wall and atherosclerotic plaques. However, it does not provide sufficient information about the histological composition of plaques to characterize their vulnerability. Arterial wall strain measurements may provide insights into plaque composition and vulnerability, complementing the information directly available in the IVUS echogram. We have developed a method to measure the transverse arterial wall strain tensor in response to luminal pressure change, by registering IVUS images acquired at different pressures. This method has been validated by using IVUS images with simulated motion and IVUS images of a vessel phantom. In this study, we further evaluate the method by assessing the correspondence of the calculated strain distribution and the histological composition of atherosclerotic coronary arteries from Sinclair miniature pigs following 12 months of a high fat diet. The images were acquired in situ using a clinical IVUS system and under computer-controlled pressurization. After image acquisition, the artery segments were fixed for histology to identify plaque components. The strain distributions were aligned with the corresponding histological sections. The stiffness of various components of the lesion, inferred from the wall strain distribution, was consistent with the tissue composition seen in the histological cross-sections. These findings suggest that strain measurements from IVUS are promising for assessing plaque vulnerability.

  9. The correspondence between coronary arterial wall strain and histology in a porcine model of atherosclerosis

    Science.gov (United States)

    Liang, Yun; Zhu, Hui; Friedman, Morton H.

    2009-09-01

    Atherosclerotic plaque rupture is the leading cause of mortality in cardiovascular disease. Intravascular ultrasound (IVUS) imaging is a powerful clinical technique that provides real-time cross-sectional images of the arterial wall and atherosclerotic plaques. However, it does not provide sufficient information about the histological composition of plaques to characterize their vulnerability. Arterial wall strain measurements may provide insights into plaque composition and vulnerability, complementing the information directly available in the IVUS echogram. We have developed a method to measure the transverse arterial wall strain tensor in response to luminal pressure change, by registering IVUS images acquired at different pressures. This method has been validated by using IVUS images with simulated motion and IVUS images of a vessel phantom. In this study, we further evaluate the method by assessing the correspondence of the calculated strain distribution and the histological composition of atherosclerotic coronary arteries from Sinclair miniature pigs following 12 months of a high fat diet. The images were acquired in situ using a clinical IVUS system and under computer-controlled pressurization. After image acquisition, the artery segments were fixed for histology to identify plaque components. The strain distributions were aligned with the corresponding histological sections. The stiffness of various components of the lesion, inferred from the wall strain distribution, was consistent with the tissue composition seen in the histological cross-sections. These findings suggest that strain measurements from IVUS are promising for assessing plaque vulnerability.

  10. Increased angiotensin II type 1 receptor expression in temporal arteries from patients with giant cell arteritis

    DEFF Research Database (Denmark)

    Dimitrijevic, Ivan; Malmsjö, Malin; Andersson, Christina

    2009-01-01

    immunohistochemical study of temporal arteries using archival formalin-fixed, paraffin-embedded tissue. PARTICIPANTS: Ten patients with GCA and 10 control patients, who were clinically suspected of having GCA but were diagnosed as not having GCA, were included. METHODS: Immunohistochemistry, using anti-AT(1) and anti......-AT(2) antibodies, was performed on formalin-fixed and paraffin-embedded temporal arteries. MAIN OUTCOME MEASURES: AT(1) and AT(2) receptor immunostaining intensity was quantified. RESULTS: Hematoxylin-eosin-stained sections of temporal arteries from patients with GCA showed intimal hyperplasia......, internal elastic lamina degeneration, and band-shaped infiltrates of inflammatory cells, including lymphocytes, histocytes, and multinucleated giant cells. AT(1) receptor staining was primarily observed in the medial layer of the temporal arteries and was higher in the patients with GCA than in the control...

  11. A review of specialties performing temporal artery biopsies in Ontario: a retrospective cohort study.

    Science.gov (United States)

    Micieli, Jonathan A; Micieli, Robert; Margolin, Edward A

    2015-01-01

    Temporal artery biopsy is the gold standard for the diagnosis of giant cell arteritis, but the numbers and types of surgical specialists performing temporal artery biopsies are unknown. The goal of this study was to determine which surgical specialists performed temporal artery biopsies and how geographic location influenced this trend over a period of 10 years. This retrospective cohort study included all physicians practising in Ontario from 2002 to 2013. Using comprehensive physician services data from the IntelliHEALTH Medical Services database, physicians performing temporal artery biopsies were identified by the Ontario Health Insurance Plan billing code submitted for remuneration. Physicians were categorized by specialty and geographic Local Health Integration Unit. A total of 9958 patients underwent a temporal artery biopsy during the study period: the biopsies were performed by 11 different subspecialties. The number of patients undergoing a temporal artery biopsy declined over the 10-year study period. Most procedures were performed by general surgeons (38.1%), followed by ophthalmologists (31.0%) and plastic surgeons (23.6%). Ophthalmologists performed more temporal artery biopsies per person compared with general surgeons, but significantly more general surgeons performed at least 1 biopsy. There was significant variation based on geographic location: plastic surgeons performed the most biopsies in regions with a population of more than 1 million people, and general surgeons performed most of the biopsies in rural areas. Geographic location heavily influenced which specialty was most likely to perform temporal artery biopsies. General surgery, ophthalmology and plastic surgery emerged as leaders in this area, and their residency programs should include formal training in this procedure in their curricula.

  12. Assymetry of temporal artery diameters during spontaneous attacks of cluster headache

    DEFF Research Database (Denmark)

    Nielsen, Thue H; Tfelt-Hansen, Peer; Iversen, Helle K

    2009-01-01

    BACKGROUND: Cluster headache is characterized by strictly unilateral head pain associated with symptoms of cranial autonomic features. Transcranial Doppler studies showed in most studies a bilateral decreased blood flow velocity in the middle cerebral artery. OBJECTIVE: To investigate whether the...... = .67). CONCLUSIONS: What was observed is most likely a general pain-induced arterial vasoconstriction (confer the decrease in diameter on the pain-free side) with an unchanged superficial temporal artery on the pain side because of some vasodilator influence....

  13. Characteristics of the response of the iliac artery to wall shear stress in the anaesthetized pig.

    Science.gov (United States)

    Kelly, R F; Snow, H M

    2007-07-15

    The functional significance of shear stress-induced vasodilatation in large conduit arteries is unclear since changes in the diameter have little effect on the resistance to blood flow. However, changes in diameter have a relatively large effect on wall shear stress which suggests that the function of flow-mediated dilatation is to reduce wall shear stress. The mean and pulsatile components of shear stress vary widely throughout the arterial system and areas of low mean and high amplitude of wall shear stress are prone to the development of atheroma. In this study, using an in vivo model with the ability to control flow rate and amplitude of flow independently, we investigated the characteristics of the response of the iliac artery to variations in both the mean and amplitude of wall shear stress. The results of this study confirm that increases in mean wall shear stress are an important stimulus for the release of nitric oxide by the endothelium as indicated by changes in arterial diameter and show for the first time, in vivo, that increases in the amplitude of the pulsatile component of shear stress have a small but significant inhibitory effect on this response. A negative feedback mechanism was identified whereby increases in shear stress brought about by increases in blood flow are reduced by the release of nitric oxide from the endothelium causing dilatation of the artery, thus decreasing the stimulus to cell adhesion and, through a direct action of nitric oxide, inhibiting the process of cell adhesion. The results also provide an explanation for the uneven distribution of atheroma throughout the arterial system, which is related to the ratio of pulsatile to mean shear stress and consequent variability in the production of NO.

  14. Free DNA precipitates calcium phosphate apatite crystals in the arterial wall in vivo.

    Science.gov (United States)

    Coscas, Raphaël; Bensussan, Marie; Jacob, Marie-Paule; Louedec, Liliane; Massy, Ziad; Sadoine, Jeremy; Daudon, Michel; Chaussain, Catherine; Bazin, Dominique; Michel, Jean-Baptiste

    2017-04-01

    The arterial wall calcium score and circulating free DNA levels are now used in clinical practice as biomarkers of cardiovascular risk. Calcium phosphate apatite retention in the arterial wall necessitates precipitation on an anionic platform. Here, we explore the role of tissue-free DNA as such a platform. The first step consisted of histological observation of samples from human and rat calcified arteries. Various stains were used to evaluate colocalization of free DNA with calcified tissue (alizarin red, fluorescent Hoechst, DNA immunostaining and TUNEL assay). Sections were treated by EDTA to reveal calcification background. Secondly, a rat model of vascular calcifications induced by intra-aortic infusions of free DNA and elastase + free DNA was developed. Rat aortas underwent a micro-CT for calcium score calculation at 3 weeks. Rat and human calcifications were qualitatively characterized using μFourier Transform Infrared Spectroscopy (μFTIR) and Field Emission-Scanning Electron Microscopy (FE-SEM). Our histological study shows colocalization of calcified arterial plaques with free DNA. In the intra-aortic infusion model, free DNA was able to penetrate into the arterial wall and induce calcifications whereas no microscopic calcification was seen in control aortas. The calcification score in the elastase + free DNA group was significantly higher than in the control groups. Qualitative evaluation with μFTIR and FE-SEM demonstrated typical calcium phosphate retention in human and rat arterial specimens. This translational study demonstrates that free DNA could be involved in arterial calcification formation by precipitating calcium phosphate apatite crystals in the vessel wall. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Combined aerobic and resistance exercise training decreases peripheral but not central artery wall thickness in subjects with type 2 diabetes.

    NARCIS (Netherlands)

    Schreuder, T.H.A.; Munckhof, I.C.L. van den; Poelkens, F.; Hopman, M.T.; Thijssen, D.H.

    2015-01-01

    OBJECTIVE: Little is known about the impact of exercise training on conduit artery wall thickness in type 2 diabetes. We examined the local and systemic impact of exercise training on superficial femoral (SFA), brachial (BA), and carotid artery (CA) wall thickness in type 2 diabetes patients and

  16. Segmental wall motion abnormalities during telerobotic totally endoscopic coronary artery bypass grafting.

    Science.gov (United States)

    Mierdl, Stephan; Byhahn, Christian; Dogan, Selami; Aybek, Tayfun; Wimmer-Greinecker, Gerhard; Kessler, Paul; Meininger, Dirk; Westphal, Klaus

    2002-04-01

    In addition to single-lung ventilation (SLV), intrathoracic CO2 insufflation is mandatory for adequate exposure during totally endoscopic coronary artery bypass grafting. With transesophageal echocardiography, we investigated biventricular myocardial wall motion in 25 patients with isolated disease of the left anterior descending coronary artery who underwent totally endoscopic coronary artery bypass grafting with the "Da Vinci" robotic surgical system. At distinct time points during the operation, a cine loop of both ventricles was registered from a transgastric mid-short-axis view. Myocardial wall motion analysis was performed according to an established segmentation model of the left ventricle and to an established five-point scale for wall motion (1, normal; 5, dyskinesia). Significant alterations from preoperative baseline wall motion were visible in the septal, inferior, and anterior segments of the left ventricle at some time during the prebypass period, combined with a markedly decreased PaO2 under SLV and increased intrathoracic pressure. The same findings applied to the right ventricle; however, wall motion abnormalities were more pronounced here. After myocardial revascularization, weaning from cardiopulmonary bypass, CO2 deflation, and return to double-lung ventilation, myocardial wall motion recovered to baseline values. Clinically significant hemodynamic instability did not occur. The data suggest that robot-assisted coronary artery bypass grafting leads to significant prebypass alterations of biventricular segmental wall motion. On the basis of our data, it cannot be definitively stated whether the observed results were due to reduced oxygenation during SLV and thus "real" myocardial ischemia, intrathoracic CO2 insufflation with positive pressure leading to mechanical compromise of the heart, absolute or relative hypovolemia, or a combination of these factors. However, in this cohort, which consisted of patients with single-vessel disease and good

  17. A New High-Resolution Spectral Approach to Noninvasively Evaluate Wall Deformations in Arteries

    Science.gov (United States)

    Bazan, Ivonne; Negreira, Carlos; Ramos, Antonio; Brum, Javier; Ramirez, Alfredo

    2014-01-01

    By locally measuring changes on arterial wall thickness as a function of pressure, the related Young modulus can be evaluated. This physical magnitude has shown to be an important predictive factor for cardiovascular diseases. For evaluating those changes, imaging segmentation or time correlations of ultrasonic echoes, coming from wall interfaces, are usually employed. In this paper, an alternative low-cost technique is proposed to locally evaluate variations on arterial walls, which are dynamically measured with an improved high-resolution calculation of power spectral densities in echo-traces of the wall interfaces, by using a parametric autoregressive processing. Certain wall deformations are finely detected by evaluating the echoes overtones peaks with power spectral estimations that implement Burg and Yule Walker algorithms. Results of this spectral approach are compared with a classical cross-correlation operator, in a tube phantom and “in vitro” carotid tissue. A circulating loop, mimicking heart periods and blood pressure changes, is employed to dynamically inspect each sample with a broadband ultrasonic probe, acquiring multiple A-Scans which are windowed to isolate echo-traces packets coming from distinct walls. Then the new technique and cross-correlation operator are applied to evaluate changing parietal deformations from the detection of displacements registered on the wall faces under periodic regime. PMID:24688596

  18. Quantifying [F-18]fluorodeoxyglucose uptake in the arterial wall

    DEFF Research Database (Denmark)

    Blomberg, Björn Alexander; Bashyam, A.; Ramachandran, A.

    2015-01-01

    -18-FDG was determined in the aortic wall by calculating the blood pool-corrected maximum standardized uptake value (cSUV(MAX)) and cSUV(MEAN). The PVE-corrected SUVMEAN (pvcSUV(MEAN)) was also calculated using F-18-FDG PET/CT and CECT images. Finally, corresponding target-to-background ratios (TBR......) were calculated. Results At 60 min, pvcSUV(MEAN) was on average 3.1 times greater than cSUV(MAX) (P pvcSUV(MEAN) was on average 2.6 times greater than cSUV(MAX) (P

  19. Smooth Muscle Specific Overexpression of p22phox Potentiates Carotid Artery Wall Thickening in Response to Injury

    Directory of Open Access Journals (Sweden)

    Michael R. Manogue

    2015-01-01

    Full Text Available We hypothesized that transgenic mice overexpressing the p22phox subunit of the NADPH oxidase selectively in smooth muscle (Tgp22smc would exhibit an exacerbated response to transluminal carotid injury compared to wild-type mice. To examine the role of reactive oxygen species (ROS as a mediator of vascular injury, the injury response was quantified by measuring wall thickness (WT and cross-sectional wall area (CSWA of the injured and noninjured arteries in both Tgp22smc and wild-type animals at days 3, 7, and 14 after injury. Akt, p38 MAPK, and Src activation were evaluated at the same time points using Western blotting. WT and CSWA following injury were significantly greater in Tgp22smc mice at both 7 and 14 days after injury while noninjured contralateral carotids were similar between groups. Apocynin treatment attenuated the injury response in both groups and rendered the response similar between Tgp22smc mice and wild-type mice. Following injury, carotid arteries from Tgp22smc mice demonstrated elevated activation of Akt at day 3, while p38 MAPK and Src activation was elevated at day 7 compared to wild-type mice. Both increased activation and temporal regulation of these signaling pathways may contribute to enhanced vascular growth in response to injury in this transgenic model of elevated vascular ROS.

  20. Trace elements in the wall of abdominal aortic aneurysms with and without coexisting iliac artery aneurysms.

    Science.gov (United States)

    Ziaja, Damian; Chudek, Jerzy; Sznapka, Mariola; Kita, Andrzej; Biolik, Grzegorz; Sieroń-Stołtny, Karolina; Pawlicki, Krzysztof; Domalik, Jolanta; Ziaja, Krzysztof

    2015-06-01

    Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15-0.40) vs. 0.32 (0-0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26-1.17) vs. 0.25 (0.20-0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.

  1. Coupled oxygen transport analysis in the avascular wall of a coronary artery stenosis during angioplasty.

    Science.gov (United States)

    Banerjee, Rupak K; Kwon, Ohwon; Vaidya, Vinayak S; Back, Lloyd H

    2008-01-01

    The coupled oxygen transport in the avascular wall of a coronary artery stenosis is studied numerically by solving the convection-diffusion equations. Two geometries replicating stenosis before and after percutaneous transluminal coronary angioplasty (PTCA) are used for the analysis. The results are compared to evaluate the effect of the degree of stenosis on oxygen transport. Important physiological aspects, such as oxygen consumption in the wall, oxygen carried by the hemoglobin, non-Newtonian viscosity of the blood, and supply of oxygen from the vasa vasorum are included. The results show that the PO2 in the medial region of the arterial wall is approximately 10mmHg. The oxygen flux to the wall increases in the flow acceleration region, whereas it decreases at the flow reattachment zone. Near the location of flow separation, there is a small rise followed by a sharp fall in the oxygen flux. The drop in the oxygen flux to the wall at the point of flow reattachment for pre-PTCA stenosis is four times that for post-PTCA stenosis. The minimum PO2 in the avascular wall, PO2,min, at this location decreases to approximately 6.0 and 4.2mmHg for post- and pre-PTCA stenosis, respectively. The drop in PO2,w and PO2,min at the point of flow reattachment for pre-PTCA is approximately 2 times that for post-PTCA stenosis. Thus, the present study quantifies the oxygen transport to the arterial wall before and after cardiovascular intervention.

  2. Targeting novel antigens in the arterial wall in thromboangiitis obliterans.

    Directory of Open Access Journals (Sweden)

    Murat Akkus

    2010-06-01

    Full Text Available Thromboangiitis obliterans is an inflammatory disease possibly resulting from cigarette smoking as a primary etiologic factor, perhaps as a delayed type of hypersensitivity or toxic angiitis. As little is known about the pathogenesis of the disease, we aimed to determine novel antigens that might be responsible from the local inflammatory reactions and structural changes observed in this disease. An indirect immunoperoxidase technique is used to examine the tissue samples obtained from the dorsalis pedis artery of affected individuals with twenty monoclonal antibodies. Among these several antigens which are not previously reported in TAO like CD34, CD44 and CD90 were determined in the tissue samples examined. On the other hand, many other antigens like cytokine/chemokine receptors, several enzymes and leukocyte/lymphocyte antigens were lacking giving some clues about the local pathological reactions. We briefly discussed our findings for several critical antigens those first described in the present work, possibly having roles in the development of the disease. Expression of the CD90/CD11c receptor/ligand pair seems to play an important role in mononuclear cell recruitment to the damage site. Vascular invasion of not only tunica intima but also the tunica media in affected vessels is clearly demonstrated using endothelial cell specific antigens.

  3. Serum carotenoids reduce progression of early atherosclerosis in the carotid artery wall among Eastern Finnish men.

    Directory of Open Access Journals (Sweden)

    Jouni Karppi

    Full Text Available BACKGROUND: Several previous epidemiologic studies have shown that high blood levels of carotenoids may be protective against early atherosclerosis, but results have been inconsistent. We assessed the association between atherosclerotic progression, measured by intima-media thickness of the common carotid artery wall, and serum levels of carotenoids. METHODS: We studied the effect of carotenoids on progression of early atherosclerosis in a population-based study. The association between concentrations of serum carotenoids, and intima-media thickness of the common carotid artery wall was explored in 840 middle-aged men (aged 46-65 years from Eastern Finland. Ultrasonography of the common carotid arteries were performed at baseline and 7-year follow-up. Serum levels of carotenoids were analyzed at baseline. Changes in mean and maximum intima media thickness of carotid artery wall were related to baseline serum carotenoid levels in covariance analyses adjusted for covariates. RESULTS: In a covariance analysis with adjustment for age, ultrasound sonographer, maximum intima media thickness, examination year, body mass index, systolic blood pressure, smoking, physical activity, serum LDL cholesterol, family history of coronary heart disease, antihypertensive medication and serum high sensitivity C-reactive protein, 7-year change in maximum intima media thickness was inversely associated with lycopene (p = 0.005, α-carotene (p = 0.002 and β-carotene (p = 0.019, respectively. CONCLUSIONS: The present study shows that high serum concentrations of carotenoids may be protective against early atherosclerosis.

  4. Relation between wall shear stress and carotid artery wall thickening MRI versus CFD

    DEFF Research Database (Denmark)

    Cibis, Merih; Potters, Wouter V.; Selwaness, Mariana

    2016-01-01

    Wall shear stress (WSS), a parameter associated with endothelial function, is calculated by computational fluid dynamics (CFD) or phase-contrast (PC) MRI measurements. Although CFD is common in WSS (WSSCFD) calculations, PC-MRI-based WSS (WSSMRI) is more favorable in population studies; since it ...

  5. Calciphylaxis: Temporal Artery Calcification Preceding Widespread Skin Lesions and Penile Necrosis

    Directory of Open Access Journals (Sweden)

    Manzoor A. Shah

    2012-01-01

    Full Text Available Temporal artery calciphylaxis has rarely been described in chronic kidney disease patients on dialysis. We report a case of 72-year-old Caucasian man with multiple comorbidities and end-stage renal disease on dialysis who presented with temporal artery calcification leading to bilateral loss of vision followed by extensive skin lesions including one on glans penis. While on peritoneal dialysis, he developed anterior ischemic optic neuropathy, had no improvement on high dose steroids, and temporal artery biopsy showed marked calcification without any evidence of vasculitis. Few weeks later on hemodialysis, he developed widespread cutaneous lesions on extremities and penile necrosis with skin biopsy revealing calciphylaxis. On literature review of calciphylaxis in chronic kidney disease, we found only four cases of temporal artery calciphylaxis leading to anterior ischemic optic neuropathy and blindness. We believe this is the first case in which the rare temporal artery calciphylaxis and the uncommon penile necrosis are being described together. The objective is to emphasize the need to recognize this condition early in the CKD patients on dialysis presenting with visual symptoms as the different treatment strategies may help prevent complete loss of vision and also modify or prevent a full blown calciphylaxis.

  6. Identification of the heart wall and chamber based on temporal change of ultrasonic scatterer distribution

    Science.gov (United States)

    Takahashi, Kohei; Taki, Hirofumi; Kanai, Hiroshi

    2017-07-01

    In most current methods for evaluating the cardiac function by ultrasound, the heart wall area is identified manually by an examiner. To eliminate examiner dependence and to improve usability, an automatic heart wall identification method is desirable. Identification based on only echogenicity often fails because of low echogenicity of some areas of the heart wall. In the present study, to determine more essential features, we focused on the relative temporal change of ultrasonic scatterer distribution and proposed three features for identification of the heart wall and the chamber: cross-correlation of RF signals, that of envelopes, and spatial dispersion of movement vectors in small regions. In an in vivo experiment, using echogenicity and the three features, we identified the heart wall and the chamber in the left ventricular long-axis view, resulting in criteria of separability J of 1.69, 1.40, and 3.02 using these features compared with the result of 0.979 using echogenicity.

  7. Automated image segmentation and registration of vessel wall MRI for quantitative assessment of carotid artery vessel wall dimensions and plaque composition

    NARCIS (Netherlands)

    Klooster, Ronald van 't

    2014-01-01

    The main goal of this thesis was to develop methods for automated segmentation, registration and classification of the carotid artery vessel wall and plaque components using multi-sequence MR vessel wall images to assess atherosclerosis. First, a general introduction into atherosclerosis and

  8. Posterior Auricular Artery-Middle Cerebral Artery Bypass: A Rare Superficial Temporal Artery Variant with Well-developed Posterior Auricular Artery—Case Report

    Science.gov (United States)

    TOKUGAWA, Joji; NAKAO, Yasuaki; KUDO, Kentaro; IIMURA, Koji; ESAKI, Takanori; YAMAMOTO, Takuji; MORI, Kentaro

    2014-01-01

    The posterior auricular artery (PAA) is one of the branches of the external carotid artery, but is usually too small for use as a donor artery for middle cerebral artery (MCA) territory revascularization. An extremely unusual case of PAA-MCA anastomosis was performed in a patient requiring MCA territory revascularization because the superficial temporal artery (STA) parietal branch was absent and the PAA was large enough. A 65-year-old man developed mild motor weakness in the right extremities caused by multiple small infarctions. Single photon emission computed tomography (CT) revealed deterioration of the vascular reserve capacity in the left MCA area. Cerebral angiography showed severe stenosis in the C2 portion of the left internal carotid artery, absence of the parietal branch of the left STA, and a well-developed PAA extending to the parietal area. The patient underwent STA (frontal branch)-MCA and PAA-MCA double anastomosis, and has suffered no stroke or transient ischemic attack. The STA with no bifurcation is known as a rare variation. The PAA also occurs with size variations but well-developed PAA is thought to be extremely rare. PAA can be used as a donor artery for MCA territory revascularization if the vessel size is suitable. Preoperative evaluation of the anatomy is mandatory for harvesting the arteries. PMID:24140773

  9. Arterial wall stiffness in patients with essential hypertension at young age

    Directory of Open Access Journals (Sweden)

    Kolesnik E.L.

    2014-11-01

    Full Text Available Research objective was investigating arterial wall stiffness in patients with hypertension at young age and assessing the relationship between subclinical target organs damage and ambulatory blood pressure monitoring (ABPM parameters. 30 male patients aged 18-35 years with essential hypertension stage I and II, hypertension 1 and 2nd grade were surveyed. The examination included general clinical methods, echocardiography, ABPM and suprasystolic sfigmography. It was found that the pulse wave velocity (PWVao (r = 0,557 p <0,01, central aortic blood pressure (SBPao (r = 0,492 p <0,01 and augmentation index (AIxao (r = 0,489 p <0.01 significantly increased with the pa¬tients’ age. Abdominal obesity (r = 0,566 p <0,01 and BMI (r = 0,599 p <0,01 impacted on the PWVao acceleration. Increasing of the left ventricular mass index (LVMI is highly associated with SBPao (r = 0,506 p <0,05 and PWVao (r = 0,434 p <0,05. According to ABPM the most significant correlation with arterial wall stiffness parameters demon¬strated diastolic blood pressure (DBP daytime level (AIxao (r = 0,418 p <0,01, with PWVao (r = 0,699 p <0.01 and SBPao (r = 0,695 p <0,01. Thus, age, excessive body weight and obesity should be considered as unfavorable factors that worsen arterial wall stiffness in patients with hypertension at the age before 35 years. Increase of DBP levels especially during the day causes maximum negative impact on the arterial wall stiffness parameters according to ABPM. Increased SBPao and PWVao in patients with hypertension at a young age are associated with increased left ventricular mass index.

  10. Fifteen new risk loci for coronary artery disease highlight arterial-wall-specific mechanisms

    DEFF Research Database (Denmark)

    Howson, Joanna M. M.; Zhao, Wei; Barnes, Daniel R

    2017-01-01

    Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide. Although 58 genomic regions have been associated with CAD thus far, most of the heritability is unexplained, indicating that additional susceptibility loci await identification. An efficient discovery strategy ...... and inflammation (PROCR, rs867186 (p.Ser219Gly)) and vascular smooth muscle cell differentiation (LMOD1, rs2820315). Correlation of these regions with cell-type-specific gene expression and plasma protein levels sheds light on potential disease mechanisms....

  11. Arterial wall mechanics as a function of heart rate: role of vascular smooth muscle

    Science.gov (United States)

    Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel

    2007-11-01

    Vascular wall viscoelasticity can be evaluated using a first-order lumped model. This model consists of a spring with elastic constant E and a dashpot with viscous constant η. More importantly, this viscoelastic model can be fitted in-vivo measuring arterial pressure and diameter. The aim of this work is to analyze the influence of heart rate over E and η. In two anesthetized sheep, diameter in thoracic aorta and intravascular pressure has been registered. The right atrium was connected to a programmable stimulator through a pair of pace-maker wires to produce changes in stimulation heart rate (HR) from 80 to 160 bpm. Additionally, local activation of vascular smooth muscle was induced with phenylephrine. After converting pressure and diameter signals into stress and strain respectively, E y η were calculated in control state and during muscle activation. The elastic modulus E did not present significant changes with heart rate. The viscous modulus η decreased 49% with a two-fold acceleration in heart rate from 80 to 160 bpm. However, the product η HR remained stable. The viscous modulus η increased 39% with smooth muscle activation. No significant pressure changes were registered during the experiment. The contractile action of vascular smooth muscle could contribute to increasing arterial wall viscosity. The decrease of η when HR increased might be related to smooth muscle relaxation mediated by endothelium activity, which was stimulated by flow increase. We conclude that HR can modulate arterial wall viscoelasticity through endothelium-dependent mechanisms.

  12. Cryopreserved human aortic root allografts arterial wall: Structural changes occurring during thawing.

    Directory of Open Access Journals (Sweden)

    Robert Novotny

    Full Text Available The aim of our experimental work was to assess morphological changes of arterial wall that arise during different thawing protocols of a cryopreserved human aortic root allograft (CHARA arterial wall.The experiment was performed on CHARAs. Two thawing protocols were tested: 1, CHARAs were thawed at a room temperature at +23°C; 2, CHARAs were placed directly into a water bath at +37°C.After fixation, all samples were washed in distilled water for 5 min, and dehydrated in a graded ethanol series (70, 85, 95, and 100% for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane for 10 minutes and air dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs, coated with gold.Thawing protocol 1: All 6 (100% samples showed loss of the endothelium and damage to the subendothelial layers with randomly dispersed circular defects and micro-fractures without smooth muscle cells contractions in the tunica media. Thawing protocol 2: All 6 (100% samples showed loss of endothelium from the luminal surface, longitudinal corrugations in the direction of blood flow caused by smooth muscle cells contractions in the tunica media with frequent fractures in the subendothelial layer.All the samples thawed at the room temperature showed smaller structural damage to the CHARA arterial wall with no smooth muscle cell contraction in tunica media when compared to the samples thawed in a water bath.

  13. Direct visualization of the arterial wall water permeability barrier using CARS microscopy.

    Science.gov (United States)

    Lucotte, Bertrand M; Powell, Chloe; Knutson, Jay R; Combs, Christian A; Malide, Daniela; Yu, Zu-Xi; Knepper, Mark; Patel, Keval D; Pielach, Anna; Johnson, Errin; Borysova, Lyudmyla; Dora, Kim A; Balaban, Robert S

    2017-05-02

    The artery wall is equipped with a water permeation barrier that allows blood to flow at high pressure without significant water leak. The precise location of this barrier is unknown despite its importance in vascular function and its contribution to many vascular complications when it is compromised. Herein we map the water permeability in intact arteries, using coherent anti-Stokes Raman scattering (CARS) microscopy and isotopic perfusion experiments. Generation of the CARS signal is optimized for water imaging with broadband excitation. We identify the water permeation barrier as the endothelial basolateral membrane and show that the apical membrane is highly permeable. This is confirmed by the distribution of the AQP1 water channel within endothelial membranes. These results indicate that arterial pressure equilibrates within the endothelium and is transmitted to the supporting basement membrane and internal elastic lamina macromolecules with minimal deformation of the sensitive endothelial cell. Disruption of this pressure transmission could contribute to endothelial cell dysfunction in various pathologies.

  14. Pulmonary arterial wall disease in COPD and interstitial lung diseases candidates for lung transplantation.

    Science.gov (United States)

    Domingo, Enric; Grignola, Juan C; Aguilar, Rio; Messeguer, Manuel López; Roman, Antonio

    2017-05-06

    Pulmonary hypertension (PH) associated with lung disease has the worst prognosis of all types of PH. Pulmonary arterial vasculopathy is an early event in the natural history of chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). The present study characterized the alterations in the structure and function of the pulmonary arterial (PA) wall of COPD and ILD candidates for lung transplantation (LTx). A cohort of 73 patients, 63 pre-LTx (30 COPD, 33 ILD), and ten controls underwent simultaneous right heart catheterisation and intravascular ultrasound (IVUS). Total pulmonary resistance (TPR), capacitance (Cp), and the TPR-Cp relationship were assessed. PA stiffness and the relative area of wall thickness were estimated as pulse PA pressure/IVUS pulsatility and as [(external sectional area-intimal area)/external sectional area] × 100, respectively. Twenty-seven percent of patients had pulmonary arterial wedge pressure > 15 mmHg and were not analyzed. PA stiffness and the area of wall thickness were increased in comparison with controls, even in patients without PH (p < 0.05). ILD patients showed a significant higher PA stiffness, and lower Cp beyond mean PA pressure (mPAP) and lower area of wall thickness than COPD patients (p < 0.05). TPR-Cp relationship was shifted downward left for ILD patients. Significant increase of PA stiffness and area of wall thickness were present even in patients without PH and can make the diagnosis of pulmonary vasculopathy at a preclinical stage in PH-lung disease candidates for LTx. ILD patients showed the worst PA stiffness and Cp with respect to COPD.

  15. Changes in pulmonary arterial wall mechanical properties and lumenal architecture with induced vascular remodeling

    Science.gov (United States)

    Molthen, Robert C.; Heinrich, Amy E.; Haworth, Steven T.; Dawson, Christopher A.

    2004-04-01

    To explore and quantify pulmonary arterial remodeling we used various methods including micro-CT, high-resolution 3-dimensional x-ray imaging, to examine the structure and function of intact pulmonary vessels in isolated rat lungs. The rat is commonly used as an animal model for studies of pulmonary hypertension (PH) and the accompanying vascular remodeling, where vascular remodeling has been defined primarily by changes in the vessel wall composition in response to hypertension inducing stimuli such as chronic hypoxic exposure (CHE) or monocrotaline (MCT) injection. Little information has been provided as to how such changes affect the vessel wall mechanical properties or the lumenal architecture of the pulmonary arterial system that actually account for the hemodynamic consequences of the remodeling. In addition, although the link between primary forms of pulmonary hypertension and inherited genetics is well established, the role that genetic coding plays in hemodynamics and vascular remodeling is not. Therefore, we are utilizing Fawn-Hooded (FH), Sprague-Dawley (SD) and Brown Norway (BN)rat strains along with unique imaging methods to parameterize both vessel distensibility and lumenal morphometry using a principal pulmonary arterial pathway analysis based on self-consistency. We have found for the hypoxia model, in addition to decreased body weight, increased hematocrit, increased right ventricular hypertrophy, the distensibility of the pulmonary arteries is shown to decrease significantly in the presence of remodeling.

  16. LB03.04: SPHYGMOMANOMETER CUFF CONSTRUCTION AND MATERIALS AFFECT TRANSMISSION OF PRESSURE FROM CUFF TO ARTERIAL WALL. FINITE ELEMENT ANALYSIS OF HUMAN PRESSURE MEASUREMENTS AND DICOM DATA.

    Science.gov (United States)

    Lewis, P; Naqvi, S; Mandal, P; Potluri, P

    2015-06-01

    Sphygmomanometer cuff pressure during deflation is assumed to equal systolic arterial pressure at the point of resumption of flow. Previous studies demonstrated that pressure decreases with increasing depth of soft tissues whilst visco-elastic characteristics of the arm tissue cause spatial and temporal variation in pressure magnitude. These generally used non-anatomical axisymmetrical arm simulations without incorporating arterial pressure variation. We used data from a volunteer's Magnetic Resonance (MR) arm scan and investigated the effect of variations in cuff materials and construction on the simulated transmission of pressure from under the cuff to the arterial wall under sinusoidal flow conditions. Pressure was measured under 8 different cuffs using Oxford Pressure Monitor Sensors placed at 90 degrees around the mid upper arm of a healthy male. Each cuff was inflated 3 times to 155 mmHg and then deflated to zero with 90 seconds between inflations. Young's modulus, flexural rigidity and thickness of each cuff was measured.Using DICOM data from the MR scan of the arm, a 3D model was derived using ScanIP and imported into Abaqus for Finite Element Analysis (FEA). Published mechanical properties of arm tissues and geometric non-linearity were assumed. The measured sub-cuff pressures were applied to the simulated arm and pressure was calculated around the brachial arterial wall. which was loaded with a sinusoidal pressure of 125/85 mmHg. FEA estimates of pressure around the brachial artery cuffs varied by up to 27 mmHg SBP and 17 mmHg DBP with different cuffs. Pressures within the cuffs varied up to 27 mmHg. Pressure transmission from the cuff to the arterial surface achieved a 95% transmission ratio with one rubber-bladdered cuff but varied between 76 and 88% for the others. Non-uniform pressure distribution around the arterial wall was strongly related to cuff fabric elastic modulus. Identical size cuffs with a separate rubber bladder produced peri-arterial

  17. Correlation between vortices and wall shear stress in a curved artery model under pulsatile flow conditions

    Science.gov (United States)

    Cox, Christopher; Plesniak, Michael W.

    2017-11-01

    One of the most physiologically relevant factors within the cardiovascular system is the wall shear stress. The wall shear stress affects endothelial cells via mechanotransduction and atherosclerotic regions are strongly correlated with curvature and branching in the human vasculature, where the shear stress is both oscillatory and multidirectional. Also, the combined effect of curvature and pulsatility in cardiovascular flows produces unsteady vortices. In this work, our goal is to assess the correlation between multiple vortex pairs and wall shear stress. To accomplish this, we use an in-house high-order flux reconstruction Navier-Stokes solver to simulate pulsatile flow of a Newtonian blood-analog fluid through a rigid 180° curved artery model. We use a physiologically relevant flow rate and generate results using both fully developed and uniform entrance conditions, the latter motivated by the fact that flow upstream to a curved artery may not be fully developed. Under these two inflow conditions, we characterize the evolution of various vortex pairs and their subsequent effect on several wall shear stress metrics. Supported by GW Center for Biomimetics and Bioinspired Engineering.

  18. Carotid Artery Wall Motion Estimation from Consecutive Ultrasonic Images: Comparison between Block-Matching and Maximum-Gradient Algorithms

    Directory of Open Access Journals (Sweden)

    Effat Soleimani

    2011-06-01

    Conclusion: Both block-matching and maximum-gradient algorithms can be used to extract the radial displacement of the carotid artery wall and in addition, with respect to the pixel size as error, the same results can be obtained.

  19. Characterization of atherosclerotic plaque of carotid arteries with histopathological correlation: Vascular wall MR imaging vs. color Doppler ultrasonography (US)

    National Research Council Canada - National Science Library

    Watanabe, Yuji; Nagayama, Masako; Suga, Tsuyoshi; Yoshida, Kazumichi; Yamagata, Sen; Okumura, Akira; Amoh, Yoshiki; Nakashita, Satoru; Van Cauteren, Marc; Dodo, Yoshihiro

    2008-01-01

    To investigate whether the vessel wall MRI of carotid arteries would differentiate at-risk soft plaque from solid fibrous plaque by identifying liquid components more accurately than color Doppler ultrasonography (US...

  20. Coronary artery bypass grafting and concomitant excision of chest wall chondrosarcoma

    Directory of Open Access Journals (Sweden)

    Ganti Somsekhar

    2009-02-01

    Full Text Available Abstract Coexistence of coronary artery disease and cancer with both requiring surgical treatment at the same time is rare. A 52 year male undergoing elective coronary artery bypass grafting was incidentally discovered to have a large soft tissue mass of variable consistency with cartilaginous elements arising from the right costal margin and adjoining ribs by a broad attachment and protruding into right pleural cavity. Frozen section suggested it to be either a chondrosarcoma or a teratoma. A wide excision of the mass with the adjoining muscle and periosteum along with quadruple coronary artery bypass grafting was done. This report is unusual on account of a being the first reported case in world literature of concomitant excision of chondrosarcoma and coronary artery bypass grafting and b the conservative management of the incidentally discovered chondrosarcoma by wide excision rather than chest wall resection with no local recurrence to date. Pathology of chondrosarcoma, in particular, and various management strategies when coronary artery disease and cancer coexist, in general, is discussed.

  1. Temporal artery biopsy is not required in all cases of suspected giant cell arteritis.

    LENUS (Irish Health Repository)

    Quinn, Edel Marie

    2012-07-01

    Temporal artery biopsy (TAB) is performed during the diagnostic workup for giant cell arteritis (GCA), a vasculitis with the potential to cause irreversible blindness or stroke. However, treatment is often started on clinical grounds, and TAB result frequently does not influence patient management. The aim of this study was to assess the need for TAB in cases of suspected GCA.

  2. Posterior Wall Capture and Femoral Artery Stenosis Following Use of StarClose Closing Device: Diagnosis and Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Stefanczyk, Ludomir [Medical University of Lodz, First Department of Radiology and Diagnostic Imaging (Poland); Elgalal, Marcin T., E-mail: telgalal@yahoo.co.uk [Medical University of Lodz, Second Department of Radiology and Diagnostic Imaging (Poland); Szubert, Wojciech; Grzelak, Piotr [Medical University of Lodz, First Department of Radiology and Diagnostic Imaging (Poland); Szopinski, Piotr [Institute of Haematology and Transfusion Medicine, Department of Vascular Surgery (Poland); Majos, Agata [Medical University of Lodz, Second Department of Radiology and Diagnostic Imaging (Poland)

    2013-10-15

    A case of femoral artery obstruction following application of a StarClose type arterial puncture closing device (APCD) is presented. Ultrasonographic and angiographic imaging of this complication was obtained. The posterior wall of the vessel was accidentally caught in the anchoring element of the nitinol clip. This complication was successfully resolved by endovascular treatment and the implantation of a stent.

  3. Plasma levels of the arterial wall protein fibulin-1 are associated with carotid-femoral pulse wave velocity

    DEFF Research Database (Denmark)

    Laugesen, Esben; Høyem, Pernille; Christiansen, Jens Sandahl

    2013-01-01

    -associated extracellular matrix protein, fibulin-1, was recently found in higher concentrations in the arterial wall and in plasma in patients with long duration type 2 diabetes. Furthermore, plasma fibulin-1 independently predicted total mortality and was associated with pulse pressure, an indirect measure of arterial...... stiffness. Whether plasma fibulin-1 is associated with arterial stiffness at earlier phases of type 2 diabetes has not been determined....

  4. Anterior Temporal Artery-to-Anterior Cerebral Artery Bypass: Anatomic Feasibility of a Novel Intracranial-Intracranial Revascularization Technique.

    Science.gov (United States)

    Meybodi, Ali Tayebi; Lawton, Michael T; Griswold, Dylan; Mokhtari, Pooneh; Payman, Andre; Yousef, Sonia; Tabani, Halima; Benet, Arnau

    2017-03-01

    Complex aneurysms of the anterior cerebral artery (ACA) may require a bypass procedure as part of their surgical management. Most current bypass paradigms recommend technically demanding side-to-side anastomosis of pericallosal arteries or use of interposition grafts, which involve longer ischemia times. The purpose of this study is to assess the feasibility of an anterior temporal artery (ATA) to ACA end-to-side bypass. Fourteen cadaveric specimens (17 ATAs) were prepared for surgical simulation. The cisternal course of the ATA was freed from perforating branches and arachnoid. The M3-M4 junction of the ATA was cut, and the artery was mobilized to the interhemispheric fissure. The feasibility of ATA bypass to the precommunicating and postcommunicating ACA was assessed in relation to the cisternal length and branching pattern of the middle cerebral artery. Successful anastomosis was feasible in 14 ATAs (82%). Three ATAs did not reach the ACA. These ATAs were branching distally and originated from the M3 (opercular) middle cerebral artery. In specimens where bypass was not feasible, the average cisternal length of the ATA was significantly shorter than the rest. ATA-ACA bypass is anatomically feasible and may be a useful alternative to other revascularization techniques in selected patients. It is technically simpler than A3-A3 in situ bypass. ATA-ACA bypass can be performed through the same pterional exposure used for the ACA aneurysms, sparing the patient an additional interhemispheric approach, required for the A3-A3 anastomosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Learning-based automated segmentation of the carotid artery vessel wall in dual-sequence MRI using subdivision surface fitting

    NARCIS (Netherlands)

    Gao, Shan; van't Klooster, Ronald; Kitslaar, Pieter H.; Coolen, Bram F.; van den Berg, Alexandra M.; Smits, Loek P.; Shahzad, Rahil; Shamonin, Denis P.; de Koning, Patrick J. H.; Nederveen, Aart J.; van der Geest, Rob J.

    2017-01-01

    Purpose: The quantification of vessel wall morphology and plaque burden requires vessel segmentation, which is generally performed by manual delineations. The purpose of our work is to develop and evaluate a new 3D model-based approach for carotid artery wall segmentation from dual-sequence MRI.

  6. Evidence for a Role of Vascular Endothelium in the Control of Arterial Wall Viscosity in Humans.

    Science.gov (United States)

    Roca, Frederic; Iacob, Michele; Remy-Jouet, Isabelle; Bellien, Jeremy; Joannides, Robinson

    2018-01-01

    Arterial wall viscosity (AWV) is a major cause of energy dissipation along the arterial tree. Its determinants remain controversial but an active endothelial regulation has been suggested. Our objective was to assess in humans the physiological role of endothelium-derived nitric oxide (NO), epoxyeicosatrienoic acids and the effect of modulating smooth muscle tone in the regulation of AWV. We simultaneously measured radial artery diameter, wall thickness, and arterial pressure in healthy volunteers during the local infusion of inhibitors of NO-synthase ( N G -monomethyl-l-arginine), epoxyeicosatrienoic acids synthesis by cytochrome P450 (fluconazole), the epoxyeicosatrienoic acids cellular targets calcium-activated potassium channels (tetraethylammonium), alone and in combination. AWV was estimated from the relative viscosity expressed as the ratio of the area of the hysteresis loop of the pressure-diameter relationship to the area under the loading phase. Arterial tone was assessed by measuring change in wall stiffness and midwall stress. N G -monomethyl-l-arginine paradoxically reduced relative viscosity (34.9±8.9%-28.9±8.6%). Conversely, relative viscosity was not modified by fluconazole (33.5±15.5%-32.0±13.6%) but increased by tetraethylammonium (31.7±6.6%-35.7±8.0%). This increase was more marked with N G -monomethyl-l-arginine+fluconazole (31.1±10.7%-43.3±13.2%) and N G -monomethyl-l-arginine+tetraethylammonium (29.5±2.3%-41.5±11.1%) compared with inhibitors alone. Sodium nitroprusside decreased AWV (35.4±2.9%-28.7±2.0%). These effects were associated with parallel change in tone but of different magnitude for similar variations in viscosity, suggesting tone-dependent and independent mechanisms. In conclusion, this is the first demonstration that the endothelial factors, NO and epoxyeicosatrienoic acids, regulate AWV in humans and support the role of arterial tone in this regulation. URL: https://eudract.ema.europa.eu. Unique identifier: RCB2007-A

  7. Chlamydia pneumoniae and atherosclerosis. Identification of bacterial DNA in the arterial wall

    Directory of Open Access Journals (Sweden)

    Coutinho Mário Sérgio Soares de Azeredo

    2000-01-01

    Full Text Available OBJECTIVE: The intracellular Gram-negative bacterium Chlamydia pneumoniae has been associated with atherosclerosis. The presence of Chlamydia pneumoniae has been investigated in fragments of the arterial wall with a technique for DNA identification. METHODS: Arterial fragments obtained from vascular surgical procedures in 58 patients were analyzed. From these patients, 39 were males and the mean age was 65±6 years. The polymerase chain reaction was used to identify the bacterial DNA with a pair of primers that codify the major outer membrane protein (MOMP of Chlamydia pneumoniae. The amplified product was visualized by electrophoresis in the 2% agarose gel stained with ethidium bromide, and it was considered positive when migrating in the band of molecular weight of the positive controls. RESULTS: Seven (12% out of the 58 patients showed positive results for Chlamydia pneumoniae. CONCLUSION: DNA from Chlamydia pneumoniae was identified in the arterial wall of a substantial number of patients with atherosclerosis. This association, which has already been described in other countries, corroborates the evidence favoring a role played by Chlamydia pneumoniae in atherogenesis.

  8. CT perfusion assessment of Moyamoya syndrome before and after direct revascularization (superficial temporal artery to middle cerebral artery bypass)

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yueqin [Hospital of Qingdao University, Department of Radiology, Qingdao (China); Hospital of Jining Medical College, CT Department, Jining (China); Xu, Wenjian [Hospital of Qingdao University, Department of Radiology, Qingdao (China); Guo, Xiang; Shi, Zhitao; Sun, Zhanguo; Wang, Jiehuan [Hospital of Jining Medical College, CT Department, Jining (China); Gao, Lingyun [Hospital of Jining Medical College, MR Department, Jining (China); Jin, Feng [Hospital of Jining Medical College, Department of Neurosurgery, Jining (China); Chen, Weijian; Yang, Yunjun [Hospital of Wenzhou Medical University, Department of Radiology, Wenzhou (China)

    2016-01-15

    To evaluate the utility of CT perfusion (CTP) for the assessment of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis in patients with Moyamoya syndrome (MMS). Twenty-four consecutive MMS patients, who underwent unilateral STA-MCA bypass surgery, received CTP before and after surgery. The relative perfusion parameter values of surgical hemispheres before treatment were compared with post-treatment values. All patients underwent CT angiography (CTA) before and after surgery in order to confirm the patency of bypass. The follow-up CTA after surgery clearly demonstrated 20 (20/24, 83.3 %) bypass arteries, whereas four (16.7 %) bypass arteries were occluded or very small. Postoperative rMTT and rTTP values (P < 0.05) of the surgical side were significantly lower than pre-operation. In patients (n = 20) with bypass patency, postoperative rCBF, rMTT and rTTP values (P < 0.05) of the surgical side were significantly improved. However, the differences of all parameters were not significant (P > 0.05) in the patients (n = 4) without bypass patency after revascularization. This study demonstrates that CTP can provide a crucial quantitative assessment of cerebral haemodynamic changes in MMS before and after STA-MCA anastomosis. (orig.)

  9. Effect of hypertension on low-density lipoprotein transport within a multi-layered arterial wall: modelling consistent with experiments

    CERN Document Server

    Jesionek, Katarzyna; Kostur, Marcin

    2016-01-01

    The influence of hypertension on low-density lipoproteins intake into the arterial wall is an important factor for understanding mechanisms of atherosclerosis. It has been experimentally observed that the increased pressure leads to the higher level of the LDL inside the wall. In this paper we attempt to construct a model of the LDL transport which reproduces quantitatively experimental outcomes. We supplement the well known four-layer arterial wall model to include two pressure induced effects: the compression of the intima tissue and the increase of the fraction of leaky junctions. We demonstrate that such model can reach the very good agreement with experimental data.

  10. Computational modelling suggests good, bad and ugly roles of glycosaminoglycans in arterial wall mechanics and mechanobiology

    Science.gov (United States)

    Roccabianca, S.; Bellini, C.; Humphrey, J. D.

    2014-01-01

    The medial layer of large arteries contains aggregates of the glycosaminoglycan hyaluronan and the proteoglycan versican. It is increasingly thought that these aggregates play important mechanical and mechanobiological roles despite constituting only a small fraction of the normal arterial wall. In this paper, we offer a new hypothesis that normal aggregates of hyaluronan and versican pressurize the intralamellar spaces, and thereby put into tension the radial elastic fibres that connect the smooth muscle cells to the elastic laminae, which would facilitate mechanosensing. This hypothesis is supported by novel computational simulations using two complementary models, a mechanistically based finite-element mixture model and a phenomenologically motivated continuum hyperelastic model. That is, the simulations suggest that normal aggregates of glycosaminoglycans/proteoglycans within the arterial media may play equally important roles in supporting (i.e. a structural role) and sensing (i.e. an instructional role) mechanical loads. Additional simulations suggest further, however, that abnormal increases in these aggregates, either distributed or localized, may over-pressurize the intralamellar units. We submit that these situations could lead to compromised mechanosensing, anoikis and/or reduced structural integrity, each of which represent fundamental aspects of arterial pathologies seen, for example, in hypertension, ageing and thoracic aortic aneurysms and dissections. PMID:24920112

  11. Two years of smoking cessation does not reduce arterial wall thickness and stiffness.

    Science.gov (United States)

    van den Berkmortel, F W P J; Wollersheim, H; van Langen, H; Smilde, T J; den Arend, J; Thien, Th

    2004-01-01

    Smoking cessation rapidly reduces cardiovascular risk. The pathophysiological mechanisms involved are still being debated. We measured structural and functional arterial wall properties of the femoral and carotid arteries after smoking cessation to investigate their possible role in cardiovascular risk reduction. Out of 127 smokers, 33 proved to stop smoking for two years. They were compared with 50 nonsmokers and 55 persistent smokers in a prospective study. Cross-sectional compliance and distensibility coefficients as well as intima-media thickness of both carotid arteries and of the right common femoral artery were measured ultrasonographically at baseline and 3, 6, 12 and 24 months after smoking cessation. The nonsmoking and persistent smokers group were measured twice at an interval of 24 months. Persistent smoking and two years of smoking cessation did not affect cross-sectional compliance and distensibility coefficients. Although at baseline intimal-medial layers were thicker in smokers, the change over time in intima-media thickness did not differ significantly between all three groups. Two years of smoking cessation was not accompanied by a slower progression or a regression in intima-media thickness nor by an improved cross-sectional compliance or distensiblity coefficient. Nevertheless, smoking cessation should be recommended as it reduces cardiovascular risk rapidly after smoking cessation.

  12. Nonlinear Optical Measurements of the Artery Wall: Parameters Related to the Progression of Atherosclerosis

    Science.gov (United States)

    Sowa, Michael G.; Mostaco-Guidolin, Leila B.; Smith, Michael S. D.; Kohlenberg, Elica K.; Ridsdale, Andrew; Stolow, Albert; Ko, Alex C. T.

    2009-01-01

    Nonlinear optical (NLO) microscopy is used to follow key structural and biochemical changes associated with the progression of atherosclerosis. Arteries from WHHL-MI rabbits are examined using a 3 channel NLO microscope that can simultaneously monitor the coherent anti-stokes Raman scattered light (CARS), the two-photon excited fluorescence (TPEF) and the second harmonic generation (SHG) from a sample. Distinct differences in the nonlinear optical signals are observed that correlate with the age of the vessel and the presence of atherosclerotic plaque. These differences are attributed to the changing extracellular matrix and the increased lipid deposition associated with plaque development. The capability of NLO to perform 3D sectioning in thick highly scattering vessels in order to visualize structural details of the artery wall and highlight vessel pathology is demonstrated. These features make NLO a potentially valuable tool to help understand the progression of atherosclerosis.

  13. A microstructurally motivated model of arterial wall mechanics with mechanobiological implications.

    Science.gov (United States)

    Bellini, C; Ferruzzi, J; Roccabianca, S; Di Martino, E S; Humphrey, J D

    2014-03-01

    Through mechanobiological control of the extracellular matrix, and hence local stiffness, smooth muscle cells of the media and fibroblasts of the adventitia play important roles in arterial homeostasis, including adaptations to altered hemodynamics, injury, and disease. We present a new approach to model arterial wall mechanics that seeks to define better the mechanical environments of the media and adventitia while avoiding the common prescription of a traction-free reference configuration. Specifically, we employ the concept of constituent-specific deposition stretches from the growth and remodeling literature and define a homeostatic state at physiologic pressure and axial stretch that serves as a convenient biologically and clinically relevant reference configuration. Information from histology and multiphoton imaging is then used to prescribe structurally motivated constitutive relations for a bi-layered model of the wall. The utility of this approach is demonstrated by describing in vitro measured biaxial pressure-diameter and axial force-length responses of murine carotid arteries and predicting the associated intact and radially cut traction-free configurations. The latter provides a unique validation while confirming that this constrained mixture approach naturally recovers estimates of residual stresses, which are fundamental to wall mechanics, without the usual need to prescribe an opening angle that is only defined conveniently on cylindrical geometries and cannot be measured in vivo. Among other findings, the model suggests that medial and adventitial stresses can be nearly uniform at physiologic loads, albeit at separate levels, and that the adventitia bears increasingly more load at supra-physiologic pressures while protecting the media from excessive stresses.

  14. Hemodynamic study of superficial temporal artery-middle cerebral artery bypass in treatment of severe internal carotid artery or middle cerebral artery stenosis

    Directory of Open Access Journals (Sweden)

    Hui LIU

    2017-07-01

    Full Text Available Objective To explore the value of dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI in superficial temporal artery-middle cerebral artery (STA-MCA bypass and to provide radiological evidence for hemodynamic changes in STA-MCA bypass in the treatment of severe internal carotid artery (ICA and MCA stenosis and/or occlusion.  Methods A total of 76 cases (65 males and 11 females with average age of 55 who underwent STA-MCA bypass from January 2011 to February 2016 were included. Routine MRI and DSC-PWI were performed within one month before operation and within one week after operation. Hemodynamic changes [relative cerebral blood flow (rCBF, relative cerebral blood volume (rCBV, relative mean transit time (rMTT and relative time to peak (rTTP] of MCA blood supplying area at basal ganglia section (proximal end and centrum semiovale section (distal end were compared before and after operation.  Results Compared with before operation, rCBF was significantly increased after operation at ipsilateral basal ganglia section (proximal end, P = 0.000 and centrum semiovale section (distal end, P = 0.001. rCBV at basal ganglia section was significantly increased after operation (P = 0.021, while rCBV at centrum semiovale section had no significant difference compared with before operation (P = 0.844. rMTT (P = 0.000, 0.000 and rTTP (P = 0.000, 0.000 at ipsilateral basal ganglia section and centrum semiovale section were significantly reduced after operation.  Conclusions STA-MCA bypass can improve cerebral blood perfusion of MCA blood supplying area. DSC-PWI could assess the hemodynamics of ischemic area, so it is the optimal noninvasive technology to evaluate the curative effect of bypass and observe cerebral hemodynamic changes dynamically. DOI: 10.3969/j.issn.1672-6731.2017.06.010

  15. Semiautomated and automated algorithms for analysis of the carotid artery wall on computed tomography and sonography: a correlation study.

    Science.gov (United States)

    Saba, Luca; Tallapally, Niranjan; Gao, Hao; Molinari, Filippo; Anzidei, Michele; Piga, Mario; Sanfilippo, Roberto; Suri, Jasjit S

    2013-04-01

    The purpose of this study was to compare automated and semiautomated algorithms for analysis of carotid artery wall thickness and intima-media thickness on multidetector row computed tomographic (CT) angiography and sonography, respectively, and to study the correlation between them. Twenty consecutive patients underwent multidetector row CT angiographic and sonographic analysis of carotid arteries (mean age, 66 years; age range, 59-79 years). The intima-media thickness of the 40 carotid arteries was measured with novel and dedicated automated software analysis and by 4 observers who manually calculated the intima-media thickness. The carotid artery wall thickness was automatically estimated by using a specific algorithm and was also semiautomatically quantified. The correlation between groups was calculated by using the Pearson ρ statistic, and scatterplots were calculated. We evaluated intermethod agreement using Bland-Altman analysis. By comparing automated carotid artery wall thickness, automated intima-media thickness, semiautomated carotid artery wall thickness, and semiautomated intima-media thickness analyses, a statistically significant association was found, with the highest values obtained for the association between semiautomated and automated intima-media thickness analyses(Pearson ρ = 0.9; 95% confidence interval, 0.82-0.95; P = 0.0001). The lowest values were obtained for the association between semiautomated intima-media thickness and automated carotid artery wall thickness analyses (Pearson ρ = 0.44; 95% confidence interval, 0.15-0.66; P = 0.0047). In the Bland-Altman analysis, the better results were obtained by comparing the semiautomated and automated algorithms for the study of intima-media thickness, with an interval of -16.1% to +43.6%. The results of this preliminary study showed that carotid artery wall thickness and intima-media thickness can be studied with automated software, although the CT analysis needs to be further improved.

  16. CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND ARTERIAL HYPERTENSION: VASCULAR WALL AS THE TARGET ORGAN IN COMORBID PATIENTS

    Directory of Open Access Journals (Sweden)

    N. A. Karoli

    2017-01-01

    Full Text Available Studies of endothelial dysfunction in patients with respiratory diseases have become relevant in recent years. Perhaps endothelial dysfunction and high arterial stiffness bind bronchopulmonary and cardiovascular diseases.Aim. To reveal features of disturbances of arterial wall vasoregulatory function in patients with chronic obstructive pulmonary disease (COPD in the presence and absence of arterial hypertension (HT.Material and methods. The study included 50 patients with COPD with normal blood pressure (BP and 85 patients with COPD and HT. Control group was presented by 20 practically healthy men comparable in age with COPD patients. Tests with reactive hyperemia (endothelium-dependent dilation and nitroglycerin (endothelium-independent dilation were performed in order to evaluate endothelium function. The number of desquamated endotheliocytes in the blood was determined.Results. In patients with COPD and HT in comparison with COPD patients without HT and healthy individuals more pronounced damages of the vascular wall, endothelium vasoregulatory function disturbances and a tendency to the reduction in endothelium-dependent vasodilation were determined both during COPD exacerbation and remission. These differences were most pronounced during the COPD exacerbation. In patients with COPD and HT in comparison with COPD patients without HT the damage of the vascular wall was more pronounced during the remission and endothelium-dependent dilatation disorder – during the exacerbation. The revealed disorders in patients with COPD and HT were associated with smoking status (r=0.61, p<0.01, severity of bronchial obstruction (r=-0.49, p<0.05, and hypoxemia (r=-0.76, p<0.01. We noted relationships between the parameters of 24-hour BP monitoring and remodeling of the brachial artery (r=0.34, p<0.05, endothelium lesion (r=0.25, p<0.05, and impairment of its vasoregulating function (r=-0.58, p<0.05. At that, the following parameters were important: the

  17. Time course of arterial remodelling in diameter and wall thickness above and below the lesion after a spinal cord injury.

    Science.gov (United States)

    Thijssen, Dick H J; De Groot, Patricia C E; van den Bogerd, Arne; Veltmeijer, Matthijs; Cable, N Timothy; Green, Daniel J; Hopman, Maria T E

    2012-12-01

    Physical inactivity in response to a spinal cord injury (SCI) represents a potent stimulus for conduit artery remodelling. Changes in conduit artery characteristics may be induced by the local effects of denervation (and consequent extreme inactivity below the level of the lesion), and also by systemic adaptations due to whole body inactivity. Therefore, we assessed the time course of carotid (i.e. above lesion) and common femoral artery (i.e. below lesion) lumen diameter and wall thickness across the first 24 weeks after an SCI. Eight male subjects (mean age 35 ± 14 years) with a traumatic motor complete spinal cord lesion between T5 and L1 (i.e. paraplegia) were included. Four subjects were measured across the first 6 weeks after SCI, whilst another four subjects were measured from 8 until 24 weeks after SCI. Ultrasound was used to examine the diameter and wall thickness from the carotid and common femoral arteries. Carotid artery diameter did not change across 24 weeks, whilst femoral artery diameter stabilised after the rapid initial decrease during the first 3 weeks after the SCI. Carotid and femoral artery wall thickness showed no change during the first few weeks, but increased both between 6 and 24 weeks (P < 0.05). In conclusion, SCI leads to a rapid and localised decrease in conduit artery diameter which is isolated to the denervated and paralyzed region, whilst wall thickness gradually increases both above and below the lesion. This distinct time course of change in conduit arterial diameter and wall thickness suggests that distinct mechanisms may contribute to these adaptations.

  18. Computational solution of the velocity and wall shear stress distribution inside a left carotid artery under pulsatile flow conditions

    Science.gov (United States)

    Arslan, Nurullah; Turmuş, Hakan

    2014-08-01

    Stroke is still one of the leading causes for death after heart diseases and cancer in all over the world. Strokes happen because an artery that carries blood uphill from the heart to the head is clogged. Most of the time, as with heart attacks, the problem is atherosclerosis, hardening of the arteries, calcified buildup of fatty deposits on the vessel wall. In this study, the fluid dynamic simulations were done in a left carotid bifurcation under the pulsatile flow conditions computationally. Pulsatile flow waveform is given in the paper. In vivo geometry and boundary conditions were obtained from a patient who has stenosis located at external carotid artery (ECA) and internal carotid artery (ICA) of his common carotid artery (CCA). The location of critical flow fields such as low wall shear stress (WSS), stagnation regions and separation regions were detected near the highly stenosed region and at branching region.

  19. Elasticity of the carotid artery walls as a prognostic factor for the occurrence of restenosis after a surgery for internal carotid artery stenosis.

    Science.gov (United States)

    Eberhardt, Andrzej; Madycki, Grzegorz; Hendiger, Włodzimierz; Staszkiewicz, Walerian; Lewszuk, Adam

    2015-01-01

    Restoration of carotid artery patency is one of the most frequently performed operations in vascular surgery. One of the most important problems that occur both short- and long-term after carotid endarterectomy is recurrent stenosis. Despite advances in imaging studies and better knowledge of the mechanisms of atherogenesis, the mechanism of restenosis remains unclear. Patients with internal carotid artery atherosclerosis experience decreased elasticity of the intima-media complex, resulting in increased vessel wall stiffness. In the future, measurement of carotid artery elasticity may become a marker for the development of post-surgical stenosis occurring after endarterectomy of both the carotid artery and other peripheral vessels. To assess the elasticity of carotid artery walls as a prognostic factor for the occurrence of restenosis after a surgery for common carotid artery stenosis. Classic carotid artery endarterectomy was performed in 180 patients selected on the basis of standard, ultrasound- based recommendations. The phenomenon of restenosis was examined using ultrasound techniques at 3, 6, 9 and 12 months after the surgery. Measurements of carotid artery elasticity were performed using a Vascular Echo Doppler device, and patients were divided into two groups depending on the occurrence (or non-occurrence) of restenosis. Group I (without restenosis) included 156 (86.6%) patients, and Group II (with restenosis) included 24 (13.4%) patients. At 3 and 6 months after the surgery, an increase of the elasticity of vessel walls (coefficient a) was observed in both groups, but the differences in the elasticity of the carotid arteries were not significant. At 12 months after the surgery, all patients in Group II (with restenosis) had significantly increased coefficient a values as compared to Group I patients (p elasticity as measured using coefficient a may be associated with the process leading to the occurrence of restenosis after the surgery. Further research

  20. New phenotypic aspects of the decidual spiral artery wall during early post-implantation mouse pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Elia, Artemis; Charalambous, Fotini [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus); Georgiades, Pantelis, E-mail: pgeor@ucy.ac.cy [Department of Biological Sciences, University of Cyprus, University Campus, P.O. Box 20537, 1678 Nicosia (Cyprus)

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Spiral artery (SA) wall remodeling (SAR) is ill-defined and clinically important. Black-Right-Pointing-Pointer SA muscular phenotype prior to and during SAR in mice is underexplored. Black-Right-Pointing-Pointer SA muscular wall consists of contractile and non-contractile components. Black-Right-Pointing-Pointer SA wall non-contractile component may be synthetic smooth muscle. Black-Right-Pointing-Pointer Timing and extent of SA wall contractile component loss is revealed. -- Abstract: During pregnancy the walls of decidual spiral arteries (SAs) undergo clinically important structural modifications crucial for embryo survival/growth and maternal health. However, the mechanisms of SA remodeling (SAR) are poorly understood. Although an important prerequisite to this understanding is knowledge about the phenotype of SA muscular wall prior to and during the beginning of mouse SAR, this remains largely unexplored and was the main aim of this work. Using histological and immunohistochemical techniques, this study shows for the first time that during early mouse gestation, from embryonic day 7.5 (E7.5) to E10.5, the decidual SA muscular coat is not a homogeneous structure, but consists of two concentric layers. The first is a largely one cell-thick sub-endothelial layer of contractile mural cells (positive for {alpha}-smooth muscle actin, calponin and SM22{alpha}) with pericyte characteristics (NG2 positive). The second layer is thicker, and evidence is presented that it may be of the synthetic/proliferative smooth muscle phenotype, based on absence ({alpha}-smooth muscle actin and calponin) or weak (SM22{alpha}) expression of contractile mural cell markers, and presence of synthetic smooth muscle characteristics (expression of non-muscle Myosin heavy chain-IIA and of the cell proliferation marker PCNA). Importantly, immunohistochemistry and morphometrics showed that the contractile mural cell layer although prominent at E7.5-E8

  1. Altered metabolism of LDL in the arterial wall precedes atherosclerosis regression.

    Science.gov (United States)

    Bartels, Emil D; Christoffersen, Christina; Lindholm, Marie W; Nielsen, Lars B

    2015-11-06

    Plasma cholesterol lowering is beneficial in patients with atherosclerosis. However, it is unknown how it affects entry and degradation of low-density lipoprotein (LDL) particles in the lesioned arterial wall. We studied the effect of lipid-lowering therapy on LDL permeability and degradation of LDL particles in atherosclerotic aortas of mice by measuring the accumulation of iodinated LDL particles in the arterial wall. Cholesterol-fed, LDL receptor-deficient mice were treated with either an anti-Apob antisense oligonucleotide or a mismatch control antisense oligonucleotide once a week for 1 or 4 weeks before injection with preparations of iodinated LDL particles. The anti-Apob antisense oligonucleotide reduced plasma cholesterol by ≈90%. The aortic LDL permeability and degradation rates of newly entered LDL particles were reduced by ≈50% and ≈85% already after 1 week of treatment despite an unchanged pool size of aortic iodinated LDL particles. In contrast, the size, foam cell content, and aortic pool size of iodinated LDL particles of aortic atherosclerotic plaques were not reduced until after 4 weeks of treatment with the anti-Apob antisense oligonucleotide. Improved endothelial barrier function toward the entry of plasma LDL particles and diminished aortic degradation of the newly entered LDL particles precede plaque regression. © 2015 American Heart Association, Inc.

  2. Segmentation of arterial walls in intravascular ultrasound cross-sectional images using extremal region selection.

    Science.gov (United States)

    Faraji, Mehdi; Cheng, Irene; Naudin, Iris; Basu, Anup

    2018-03-01

    Intravascular Ultrasound (IVUS) is an intra-operative imaging modality that facilitates observing and appraising the vessel wall structure of the human coronary arteries. Segmentation of arterial wall boundaries from the IVUS images is not only crucial for quantitative analysis of the vessel walls and plaque characteristics, but is also necessary for generating 3D reconstructed models of the artery. The aim of this study is twofold. Firstly, we investigate the feasibility of using a recently proposed region detector, namely Extremal Region of Extremum Level (EREL) to delineate the luminal and media-adventitia borders in IVUS frames acquired by 20 MHz probes. Secondly, we propose a region selection strategy to label two ERELs as lumen and media based on the stability of their textural information. We extensively evaluated our selection strategy on the test set of a standard publicly available dataset containing 326 IVUS B-mode images. We showed that in the best case, the average Hausdorff Distances (HD) between the extracted ERELs and the actual lumen and media were 0.22  mm and 0.45 mm, respectively. The results of our experiments revealed that our selection strategy was able to segment the lumen with ⩽0.3 mm HD to the gold standard even though the images contained major artifacts such as bifurcations, shadows, and side branches. Moreover, when there was no artifact, our proposed method was able to delineate media-adventitia boundaries with 0.31 mm HD to the gold standard. Furthermore, our proposed segmentation method runs in time that is linear in the number of pixels in each frame. Based on the results of this work, by using a 20 MHz IVUS probe with controlled pullback, not only can we now analyze the internal structure of human arteries more accurately, but also segment each frame during the pullback procedure because of the low run time of our proposed segmentation method. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. [Diagnostic value of clinical signs in giant cell arteritis: analysis of 415 temporal artery biopsy findings].

    Science.gov (United States)

    Strady, Christophe; Arav, Eric; Strady, Alain; Jaussaud, Roland; Beguinot, Isabelle; Rouger, Christine; Pluot, Michel; Remy, Gérard

    2002-02-01

    The American College of Rheumatology (ACR) has proposed a list of criteria for diagnosis of giant cell arteritis in order to guide clinical research by differentiating it from other vasculitis. The aim of this retrospective investigation, based on the findings of 415 temporal artery biopsies was to assess the diagnostic value of these criteria in the daily clinical setting. The demographic, clinical and biological characteristics of patients with positive (confirmed cases of giant cell arteritis) or negative (controls) histopathological temporal artery biopsy findings were analyzed using downward step-by-step logistic regression analysis. This analysis enabled investigators to list signs with inherent diagnostic value. Based their odds-ratio, these factors were used to determine a clinical score for giant cell arteritis. A score of over 7 - out of a maximum score of 32 - enables the diagnosis for giant cell arteritis with the best possible compromise between a sensitivity of 75.7% and a specificity of 72.2%. ACR criteria had a sensitivity of 97.5% and a specificity of 78.9% when used in our patient group. Our study results are original in that the control group was composed of patients in whom the diagnosis of giant cell arteritis had been suggested but refuted by the absence of histopathological findings on the temporal artery biopsy. This pragmatic attitude in selecting the control group may explain the difference observed with the ACR criteria in terms of sensitivity and specificity. Further research is needed to develop a diagnostic method for giant cell arteritis without resorting to temporal artery biopsy.

  4. Coronary artery visibility in free-breathing young children on non-gated chest CT: impact of temporal resolution

    Energy Technology Data Exchange (ETDEWEB)

    Bridoux, Alexandre; Hutt, Antoine; Faivre, Jean-Baptiste; Pagniez, Julien; Remy, Jacques; Remy-Jardin, Martine [CHRU et Universite de Lille, Department of Thoracic Imaging, Hospital Calmette (EA 2694), 59037 Lille Cedex (France); Flohr, Thomas [Siemens Healthcare, Department of Research and Development in CT, Forchheim (Germany); Duhamel, Alain [Universite de Lille, Department of Biostatistics, Lille (France)

    2015-11-15

    Dual-source CT allows scanning of the chest with high pitch and high temporal resolution, which can improve the detection of proximal coronary arteries in infants and young children when scanned without general anesthesia, sedation or beta-blockade. To compare coronary artery visibility between higher and standard temporal resolution. We analyzed CT images in 93 children who underwent a standard chest CT angiographic examination with reconstruction of images with a temporal resolution of 75 ms (group 1) and 140 ms (group 2). The percentage of detected coronary segments was higher in group 1 than in group 2 when considering all segments (group 1: 27%; group 2: 24%; P = 0.0004) and proximal segments (group 1: 37%; group 2: 32%; P = 0.0006). In both groups, the highest rates of detection were observed for the left main coronary artery (S1) (group 1: 65%; group 2: 58%) and proximal left anterior descending coronary artery (S2) (group 1: 43%; group 2: 42%). Higher rates of detection were seen in group 1 for the left main coronary artery (P = 0.03), proximal right coronary artery (P = 0.01), proximal segments of the left coronary artery (P = 0.02) and proximal segments of the left and right coronary arteries (P = 0.0006). Higher temporal resolution improved the visibility of proximal coronary arteries in pediatric chest CT. (orig.)

  5. Internal Maxillary Artery to Upper Posterior Circulation Bypass Using a Superficial Temporal Artery Graft: Surgical Anatomy and Feasibility Assessment.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Lawton, Michael T; Rodriguez Rubio, Roberto; Yousef, Sonia; Guo, Xiaoming; Feng, Xuequan; Benet, Arnau

    2017-11-01

    Revascularization of the upper posterior circulation (UPC), including the superior cerebellar artery (SCA) and posterior cerebral artery (PCA), may be necessary as part of the surgical treatment of complex UPC aneurysms or vertebrobasilar insufficiency. The existing bypass options have relative advantages and disadvantages. However, the use of a superficial temporal artery graft (STAg) in a bypass from the internal maxillary artery (IMA) to the UPC has not been previously assessed. We studied the surgical anatomy and assessed the technical feasibility of the IMA-STAg-UPC bypass. Fourteen cadaver heads were studied. The STAg was harvested proximally from about 15 mm below the zygomatic arch. The IMA was exposed through the lateral triangle of the middle fossa. The IMA-STAg-UPC bypass was completed using a subtemporal approach. The bypass was successfully performed in all specimens. The average length of the STAg from the donor to the recipient was 46.4 mm for the s2 SCA, and 49.5 mm for the P2 PCA. The average distal diameter of the STAg was 2.3 mm. More than 83% of STAgs had a diameter of ≥2 mm distally. At the point of anastomosis, the average diameter of the SCA was 1.9 mm, and the average diameter of the PCA was 3.0 mm. The proposed bypass is anatomically feasible and provides a suitable caliber match between the bypass components. Our results provide the anatomic basis for clinical assessment of the bypass in tackling complex lesions of the vertebrobasilar system requiring revascularization. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Changes in Water Filtration Velocity and Wall Structure of the Rabbit Common Carotid Artery after Removal of the Adventitia

    Science.gov (United States)

    Wada, Shigeo; Kaichi, Masashi; Karino, Takeshi

    To investigate the effect of the changes in water filtration velocity on the structure of an arterial wall, measurements of water filtration velocity and microscopic observation of histological specimens of the rabbit common carotid arteries were carried out by surgically removing the adventitia of the arteries and harvesting them at different times postoperatively. It was found that by removal of the adventitia, water filtration velocity at the arterial wall increased temporarily, and then as healing of the adventitia progressed, it decreased gradually until water filtration velocity attained almost the same value as that obtained with intact arteries. Intimal thickening was observed in those vessels harvested at 7 and 14 days postoperatively. Furthermore, it was shown by theoretical calculations that the concentration of low-density lipoprotein, which is a main carrier of cholesterol in blood, was locally elevated at the luminal surface of the segment where water filtration velocity was increased by removal of the adventitia. These results indicate that the change in water filtration velocity at the vessel wall brings about certain changes in the structure of the vessel wall.

  7. Mechanobiology of LDL mass transport in the arterial wall under the effect of magnetic field, part I: Diffusion rate

    Energy Technology Data Exchange (ETDEWEB)

    Aminfar, Habib, E-mail: hh_aminfar@tabrizu.ac.ir [Faculty of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of); Mohammadpourfard, Mousa, E-mail: Mohammadpour@tabrizu.ac.ir [Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz 5166616471 (Iran, Islamic Republic of); Khajeh, Kosar, E-mail: k.khajeh.2005@tabrizu.ac.ir [Faculty of Mechanical Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2017-03-15

    It is well-known that the Low Density Lipoprotein (LDL) can accumulate and penetrate into the arterial wall. Here, we have investigated the diffusion rate of macromolecules across the porous layer of blood vessel under the effects of magnetic force. By using a finite volume technique, it was found that magnetic field makes alterations in diffusion rate of LDLs, also surface concentration of macromolecules on the walls. As well, the influence of different value of Re and Sc number in the presence of a magnetic field have shown as nondimensional concentration profiles. Magnetic field considered as a body force, porous layer simulated by using Darcy's law and the blood regarded as nano fluid which was examined as a single phase model. - Highlights: • LDLs mass transfer across the arterial wall under magnetic field has simulated numerically. • Arterial wall assumed as a homogeneous porous layer by using Darcy's law. • Blood containing 4% Vol. Fe{sub 3}O{sub 4} regarded as nanofluid and has examined by single phase model. • Magnetic field significantly affects the diffusion rate of LDLs through porous arterial wall.

  8. A simulation environment for validating ultrasonic blood flow and vessel wall imaging based on fluid-structure interaction simulations: ultrasonic assessment of arterial distension and wall shear rate.

    Science.gov (United States)

    Swillens, Abigail; Degroote, Joris; Vierendeels, Jan; Lovstakken, Lasse; Segers, Patrick

    2010-08-01

    Ultrasound (US) is a commonly used vascular imaging tool when screening for patients at high cardiovascular risk. However, current blood flow and vessel wall imaging methods are hampered by several limitations. When optimizing and developing new ultrasound modalities, proper validation is required before clinical implementation. Therefore, the authors present a simulation environment integrating ultrasound and fluid-structure interaction (FSI) simulations, allowing construction of synthetic ultrasound images based on physiologically realistic behavior of an artery. To demonstrate the potential of the model for vascular ultrasound research, the authors studied clinically relevant imaging modalities of arterial function related to both vessel wall deformation and arterial hemodynamics: Arterial distension (related to arterial stiffness) and wall shear rate (related to the development of atherosclerosis) imaging. An in-house code ("TANGO") was developed to strongly couple the flow solver FLUENT and structural solver ABAQUS using an interface quasi-Newton technique. FIELD II was used to model realistic transducer and scan settings. The input to the FSI-US model is a scatterer phantom on which the US waves reflect, with the scatterer displacement derived from the FSI flow and displacement fields. The authors applied the simulation tool to a 3D straight tube, representative of the common carotid artery (length: 5 cm; and inner and outer radius: 3 and 4 mm). A mass flow inlet boundary condition, based on flow measured in a healthy subject, was applied. A downstream pressure condition, based on a noninvasively measured pressure waveform, was chosen and scaled to simulate three different degrees of arterial distension (1%, 4%, and 9%). The RF data from the FSI-US coupling were further processed for arterial wall and flow imaging. Using an available wall tracking algorithm, arterial distensibility was assessed. Using an autocorrelation estimator, blood velocity and shear

  9. Influence of the myocardial bridging phenomenon on the myocardial structure and the coronary arteries wall structure changes

    Directory of Open Access Journals (Sweden)

    Tomanović-Koković Jelena

    2006-01-01

    Full Text Available Background/Aim. Our research was performed to evaluate the influences of the myocardial bridging of coronary arteries on the myocardial and coronary arteries wall structure changes, that could be a reason for multiple heart malfunctions. Methods. We analyzed the autopsy material, collected during a five-years period, and especially the group of 575 cases with the major aim to diagnose mors naturalis. In all cases with the presence of myocardial bridge over the arterial coronary wall revealed at autopsy, samples were taken for microscopic verification and examination. Results. We found myocardial bridges over the coronary arteries or their major branches in 27 of the cases (4.70%. We believe that myocardial bridges compromise coronary perfusion by cyclic compression of the overbridged vessels, and that it could be the initial factor in the pathogenesis of arteriosclerotic degeneration processes on the coronary artery wall. We found different grades of arteriosclerotic changes in 88.89% of the cases, as well as fibrosis of myocardium in 88.89% and lipomatosis in 66.67% of the cases with the present myocardial bridges. Conclusion. Our results suggested that myocardial bridging of coronary arteries and/or their branches was the pathological and even lethal phenomenon that deserves more intensive clinical evaluation.

  10. Integration of a capacitive pressure sensing system into the outer catheter wall for coronary artery FFR measurements

    Science.gov (United States)

    Stam, Frank; Kuisma, Heikki; Gao, Feng; Saarilahti, Jaakko; Gomes Martins, David; Kärkkäinen, Anu; Marrinan, Brendan; Pintal, Sebastian

    2017-05-01

    The deadliest disease in the world is coronary artery disease (CAD), which is related to a narrowing (stenosis) of blood vessels due to fatty deposits, plaque, on the arterial walls. The level of stenosis in the coronary arteries can be assessed by Fractional Flow Reserve (FFR) measurements. This involves determining the ratio between the maximum achievable blood flow in a diseased coronary artery and the theoretical maximum flow in a normal coronary artery. The blood flow is represented by a pressure drop, thus a pressure wire or pressure sensor integrated in a catheter can be used to calculate the ratio between the coronary pressure distal to the stenosis and the normal coronary pressure. A 2 Fr (0.67mm) outer diameter catheter was used, which required a high level of microelectronics miniaturisation to fit a pressure sensing system into the outer wall. The catheter has an eccentric guidewire lumen with a diameter of 0.43mm, which implies that the thickest catheter wall section provides less than 210 microns height for flex assembly integration consisting of two dies, a capacitive MEMS pressure sensor and an ASIC. In order to achieve this a very thin circuit flex was used, and the two chips were thinned down to 75 microns and flip chip mounted face down on the flex. Many challenges were involved in obtaining a flex layout that could wrap into a small tube without getting the dies damaged, while still maintaining enough flexibility for the catheter to navigate the arterial system.

  11. Superficial temporal artery-middle cerebral artery bypass surgery in a pediatric giant intracranial aneurysm presenting as migraine-like episodes.

    Science.gov (United States)

    Goedee, H S; Depauw, P R A M; vd Zwam, B; Temmink, A H

    2009-02-01

    Aneurysms of the intracranial arteries in the pediatric population are reportedly rare. There is a male predominance, association with connective tissue disorders, as well as bacterial, mycotic infections, and trauma. Common sites of presentation are the internal carotid artery bifurcation, posterior circulation, and distal segment of middle cerebral artery. Clinical manifestations can vary from seizures and subarachnoidal hemorrhage to headache, irritability, lethargy, vomiting, or focal motor deficits. Current treatment modalities encompass endovascular or surgical approach. We present a case report on an 11-year-old girl with migraine-like episodes due to an underlying giant fusiform middle cerebral artery aneurysm treated successfully with two superficial temporal artery-middle cerebral artery bypasses.

  12. Arterialización venosa temporal del pie diabético Temporal venous arterialization of the diabetic foot

    Directory of Open Access Journals (Sweden)

    Francisco Lengua

    2010-01-01

    ón en el pie diabético es posible, eficaz y durable, gracias, posiblemente, a la inducción de una neoarteriogénesis y neoangiogénesis, que mantiene los beneficios aun después de que el puente se haya ocluido (función temporal.Background: The first idea of surgeons (1902 to avoid amputations due to ischemia was to deviate the arterial flow to the venous system using an arteriovenous fistula between adjacent vessels; however, the results were unreliable. Since then, sympathectomies, endarterectomies and bypasses have been created, and more recently, other medical, surgical, and endovascular advances have been used. However, amputations continue to be performed worldwide mainly in diabetic patients. The arterialization of the foot veins, based on the old idea of inverted blood flow, is a new possibility for these patients who, otherwise, could lose their limbs. Objective: To demonstrate that arterialization of the foot veins in diabetic patients with neuroischemic lesions, usually infected (diabetic foot, is an effective and long-lasting method, even though the bypass only works temporally. Patients and method: From January 2000 to February 2009, 59 patients with diabetic foot were threated by means of arterialization of the foot veins. An early death was not included in the analysis. Of the 58 remaining patients, 44 were male and 14 were female. Their mean age was 71 years old: (53-91 years. Fifty-four of them were classified as being Fontaine IV and four were IIIB. The arterialization was conducted using an inverted venous graft proximally anastomized to an artery presenting good flow (external iliac, femoral or popliteal arteries distally in the internal marginal vein of the foot, eliminating the valves of the foot arch veins. Results: Of the 58 patients who underwent arterialization, 12 failed due to early thrombosis, having amputated limbs, and 46 succeeded (79%: six at short-term, 12 at medium-term, and 28 at long-term. In the groups who were considered to have

  13. Association between proximal internal carotid artery steno-occlusive disease and diffuse wall thickening in its petrous segment: a magnetic resonance vessel wall imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaoyi; Li, Dongye [Capital Medical University and Beijing Institute for Brain Disorders, Center for Brain Disorders Research, Beijing (China); Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Zhao, Huilin [Shanghai Jiao Tong University, Department of Radiology, Renji Hospital, School of Medicine, Shanghai (China); Chen, Zhensen; Qiao, Huiyu; He, Le; Li, Rui [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Cui, Yuanyuan [PLA General Hospital, Department of Radiology, Beijing (China); Zhou, Zechen [Philips Research China, Healthcare Department, Beijing (China); Yuan, Chun [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); University of Washington, Department of Radiology, Seattle, WA (United States); Zhao, Xihai [Tsinghua University School of Medicine, Center for Biomedical Imaging Research, Department of Biomedical Engineering, Beijing (China); Beijing Institute for Brain Disorders, Center for Stroke, Beijing (China)

    2017-05-15

    Significant stenosis or occlusion in carotid arteries may lead to diffuse wall thickening (DWT) in the arterial wall of downstream. This study aimed to investigate the correlation between proximal internal carotid artery (ICA) steno-occlusive disease and DWT in ipsilateral petrous ICA. Symptomatic patients with atherosclerotic stenosis (>0%) in proximal ICA were recruited and underwent carotid MR vessel wall imaging. The 3D motion sensitized-driven equilibrium prepared rapid gradient-echo (3D-MERGE) was acquired for characterizing the wall thickness and longitudinal extent of the lesions in petrous ICA and the distance from proximal lesion to the petrous ICA. The stenosis degree in proximal ICA was measured on the time-of-flight (TOF) images. In total, 166 carotid arteries from 125 patients (mean age 61.0 ± 10.5 years, 99 males) were eligible for final analysis and 64 showed DWT in petrous ICAs. The prevalence of severe DWT in petrous ICA was 1.4%, 5.3%, 5.9%, and 80.4% in ipsilateral proximal ICAs with stenosis category of 1%-49%, 50%-69%, 70%-99%, and total occlusion, respectively. Proximal ICA stenosis was significantly correlated with the wall thickness in petrous ICA (r = 0.767, P < 0.001). Logistic regression analysis showed that proximal ICA stenosis was independently associated with DWT in ipsilateral petrous ICA (odds ratio (OR) = 2.459, 95% confidence interval (CI) 1.896-3.189, P < 0.001). Proximal ICA steno-occlusive disease is independently associated with DWT in ipsilateral petrous ICA. (orig.)

  14. Small-vessel vasculitis surrounding an uninflamed temporal artery: a new diagnostic criterion for polymyalgia rheumatica?

    Science.gov (United States)

    Chatelain, Denis; Duhaut, Pierre; Loire, Robert; Bosshard, Sylvie; Pellet, Hélène; Piette, Jean-Charles; Sevestre, Henri; Ducroix, Jean-Pierre

    2008-08-01

    To assess the prevalence and clinical significance of small-vessel vasculitis (SVV) surrounding an uninflamed temporal artery (TA) in patients diagnosed as having giant cell (temporal) arteritis (GCA) and/or polymyalgia rheumatica (PMR). Patients with GCA and/or PMR (n = 490) were included in this multicenter prospective study. Slides of TA biopsy specimens were reviewed by 2 pathologists who were blinded with regard to clinical information. SVV was defined as aggregates of mononuclear inflammatory cells surrounding a capillary, distant from an uninflamed temporal artery. Clinical and biologic data of patients in the SVV group (n = 35) were compared with data of patients with biopsy-proven GCA (n = 280) and with negative TA biopsy findings (n = 175). SVV was diagnosed in 18 women and 17 men (mean +/- SD age 74.5 +/- 9.4 years). The group of patients with SVV had a higher proportion of men than in the entire GCA series, had systemic symptoms, headache, jaw claudication, and an abnormal temporal artery less frequently at clinical examination, but had symptoms of PMR more often than patients in the biopsy-proven GCA group (P = 2.6 x 10(-7), odds ratio 9.17 [95% confidence interval 3.44-24.4]). Levels of inflammation markers were significantly lower in the SVV group. Patients in the SVV group had fever less frequently than patients in the group with negative TA biopsy findings, but otherwise shared the same clinical (including PMR symptoms) and biologic features. Eighteen of the 94 patients with pure PMR (19%) had SVV. SVV is often neglected by pathologists, and appears to be strongly associated with PMR symptoms in patients with a clinical diagnosis of GCA and/or PMR. However, SVV as a new diagnostic criterion for PMR must be assessed in prospective studies.

  15. NONINVASIVE EVALUATION OF VASCULAR WALL STIFFNESSIN HEALTHY ADOLESCENTS, THE RISK FACTORS FOR ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    G. P. Filippov

    2015-01-01

    Full Text Available Objective. To evaluate the main indicators characterizing the rigidity of the vascular wall in healthy ado-lescents with such risk factors (RF for arterial hypertension (AH as a family history on hypertension and smoking. Identify changes in the initial elastic-elastic properties of the arteries at the preclinical stage of development of hypertension.Material and methods. It was formed two groups of comparison. Age studied from 13 to 17 years (mean age (15.00 ± 0.31 years. The first group consisted of 30 healthy adolescents whose parents suffer from hypertension from a young age. The second group consisted of 30 healthy smokers teenager from healthy parents. The control group consisted of 30 healthy adolescents from healthy parents. Determines the basic stiffness of the vascular wall: PWV, CAVI, SAI.Results. A significant in crease in the indicators characterizing the rigidity of the vascular wall in the two comparison groups relative to the control. PWV: 6,89 ± 0,56 (first group, 7.13 ± 0.55 (second group and 5.5 ± 0.41 (control, p < 0.05.L-CAVI: 5,46 ± 0,39 (first group, 5.84 ± 0.61 (second group and 4.32 ± 0.41 (control, p < 0.05.R-CAVI: 5,63 ± 0,39 (first group, 5.89 ± 0.56 (second group and 4.49 ± 0.41(control, p < 0.05. R-AI: 0,89 ± 0,09 (first group, 0.95 ± 0.12 (second group and 0.62 ± 0.1 (control, p < 0.05.Smoking teenagers and adolescents with family history of hypertension, there are changes in the initial stiffness of the vessel wall, which requires the allocation of at-riskfor the development of hypertension and prevention activities at the preclinical stage of development ofthe disease.

  16. Temporal slow-growth formulation for direct numerical simulation of compressible wall-bounded flows

    Science.gov (United States)

    Topalian, Victor; Oliver, Todd A.; Ulerich, Rhys; Moser, Robert D.

    2017-08-01

    A slow-growth formulation for DNS of wall-bounded turbulent flow is developed and demonstrated to enable extension of slow-growth modeling concepts to wall-bounded flows with complex physics. As in previous slow-growth approaches, the formulation assumes scale separation between the fast scales of turbulence and the slow evolution of statistics such as the mean flow. This separation enables the development of approaches where the fast scales of turbulence are directly simulated while the forcing provided by the slow evolution is modeled. The resulting model admits periodic boundary conditions in the streamwise direction, which avoids the need for extremely long domains and complex inflow conditions that typically accompany spatially developing simulations. Further, it enables the use of efficient Fourier numerics. Unlike previous approaches [Guarini, Moser, Shariff, and Wray, J. Fluid Mech. 414, 1 (2000), 10.1017/S0022112000008466; Maeder, Adams, and Kleiser, J. Fluid Mech. 429, 187 (2001), 10.1017/S0022112000002718; Spalart, J. Fluid Mech. 187, 61 (1988), 10.1017/S0022112088000345], the present approach is based on a temporally evolving boundary layer and is specifically tailored to give results for calibration and validation of Reynolds-averaged Navier-Stokes (RANS) turbulence models. The use of a temporal homogenization simplifies the modeling, enabling straightforward extension to flows with complicating features, including cold and blowing walls. To generate data useful for calibration and validation of RANS models, special care is taken to ensure that the mean slow-growth forcing is closed in terms of the mean and other quantities that appear in standard RANS models, ensuring that there is no confounding between typical RANS closures and additional closures required for the slow-growth problem. The performance of the method is demonstrated on two problems: an essentially incompressible, zero-pressure-gradient boundary layer and a transonic boundary layer over

  17. Ultrasonic Measurement of Transient Change in Stress-Strain Property of Radial Arterial Wall Caused by Endothelium-Dependent Vasodilation

    Science.gov (United States)

    Ikeshita, Kazuki; Hasegawa, Hideyuki; Kanai, Hiroshi

    2008-05-01

    The endothelial dysfunction is considered to be an initial step of atherosclerosis. Additionally, it was reported that the smooth muscle, which constructs the media of the artery, changes its characteristics owing to atherosclerosis. Therefore, it is essential to develop a method for assessing the regional endothelial function and mechanical property of the arterial wall. There is a conventional technique of measuring the transient change in the diameter of the brachial artery caused by flow-mediated dilation (FMD) after the release of avascularization. For more sensitive and regional evaluation, we developed a method of measuring the change in the elasticity of the radial artery due to FMD. In this study, the transient change in the mechanical property of the arterial wall was further revealed by measuring the stress-strain relationship during each heartbeat. The minute change in the thickness (strain) of the radial arterial wall during a cardiac cycle was measured by the phased tracking method, together with the waveform of blood pressure which was continuously measured with a sphygmometer at the radial artery. The transient change in stress-strain relationship during a cardiac cycle was obtained from the measured changes in wall thickness and blood pressure to show the transient change in instantaneous viscoelasticity. From the in vivo experimental results, the stress-strain relationship shows the hysteresis loop. The slope of the loop decreased owing to FMD, which shows that the elastic modulus decreased, and the increasing area of the loop depends on the ratio of the loss modulus (depends on viscosity) to the elastic modulus when the Voigt model is assumed. These results show a potential of the proposed method for the thorough analysis of the transient change in viscoelasticity due to FMD.

  18. The composite aortic wall graft technique: an option for a short coronary artery bypass graft

    Directory of Open Access Journals (Sweden)

    João Bosco de Oliveira

    2009-01-01

    Full Text Available SUMMARY: During coronary artery bypass graft (CABG surgery, the saphenous vein is sutured through its proximal segment to the aorta. Intimal hyperplasia is one of the possible causes of graft occlusion. Notably, blood turbulence can induce wall shear stress that may also play an important role in this process. OBJECTIVE: We propose a new technique for performing proximal anastomosis to avoid CABG failure. METHOD: An 80 kg pig was subjected to open heart surgery. Four stitches were placed in the anterior ascending aorta, which formed a 2 cm by 4 cm patch. This patch was isolated through the application of a tangential clamp that was oriented parallel to the axis of the aorta. After releasing the patch, which was held to the aorta through its cranial end pedicle, the rims were sutured to each other creating a conduit with a length of 4 cm and an internal diameter of 4 mm. The rest of the aortotomy was closed by placing a direct suture between its rims. RESULT: This novel technique created an "in situ" aortic wall graft that was 4 cm long and characterized as being of uniform 4 mm caliber.

  19. Difference between Outcome of Left Circumflex Artery and Right Coronary Artery Related Acute Inferior Wall Myocardial Infarction in Patients Undergoing Adjunctive Angioplasty after Fibrinolysis.

    Science.gov (United States)

    Sohrabi, Bahram; Separham, Ahmad; Madadi, Reza; Toufan, Mehrnoush; Mohammadi, Nasibeh; Aslanabadi, Naser; Kazemi, Babak

    2014-01-01

    Prognostic differences between anterior and inferior wall Myocardial Infarction (MI) has been extensively investigated, but there is limited information about similar comparison between inferior wall MI caused by right coronary artery (RCA) and left circumflex artery (LCX) occlusion. The aim of present study was to compare prognostic differences between LCX- and RCA-related acute inferior wall ST-segment elevation MI (STEMI) treated by routine adjunctive angioplasty after receiving thrombolytic therapy (TLT). Between March 2012 and June 2013 one hundred fifty consecutive patients with acute inferior wall STEMI were studied. Patients were divided into two groups according to the infarct related artery (LCX vs. RCA). All patients underwent routine adjunctive angioplasty after TLT during the index hospitalization and clinical characteristics and outcomes were compared. RCA and LCX arteries were occluded in 97 (64.7%) and 53 (35.3%) of patients, respectively. Two groups were similar in baseline characteristics except multiple-vessel disease was more prevalent with LCX occlusion (p= 0.008). There was a higher cardiac enzyme release (p< 0.001), more significant mitral regurgitation (MR) (p= 0.015), and lower left ventricular ejection fraction (LVEF) (p= 0.01) in patients with LCX occlusion. Multivariate analysis showed cTn-I release, occurrence of MR, and lower LVEF as independent factors leading to poor outcome. There were higher cTn-I release, MR occurrence, and lower LVEF in LCX-related acute inferior wall STEMI, all associated with poor outcome. Therefore, patients with ECG finding in favour of LCX occlusion should be considered as high risk and an invasive approach should be planned.

  20. The role of the carotid sinus in the reduction of arterial wall stresses due to head movements--potential implications for cervical artery dissection.

    Science.gov (United States)

    Callaghan, F M; Soellinger, M; Baumgartner, R W; Poulikakos, D; Boesiger, P; Kurtcuoglu, V

    2009-04-16

    Spontaneous dissection of the cervical internal carotid artery (sICAD) is a major cause of stroke in young adults. A tear in the inner part of the vessel wall triggers sICAD as it allows the blood to enter the wall and develop a transmural hematoma. The etiology of the tear is unknown but many patients with sICAD report an initiating trivial trauma. We thus hypothesised that the site of the tear might correspond with the location of maximal stress in the carotid wall. Carotid artery geometries segmented from magnetic resonance images of a healthy subject at different static head positions were used to define a path of motion and deformation of the right cervical internal carotid artery (ICA). Maximum head rotation to the left and rotation to the left combined with hyperextension of the neck were investigated using a structural finite element model. A role of the carotid sinus as a geometrically compliant feature accommodating extension of the artery is shown. At the extreme range of the movements, the geometrical compliance of the carotid sinus is limited and significant stress concentrations appear just distal to the sinus with peak stresses at the internal wall on the posterior side of the vessel following maximum head rotation and on the anteromedial portion of the vessel wall following rotation and hyperextension. Clinically, the location of sICAD initiation is 10-30 mm distal to the origin of the cervical ICA, which corresponds with the peak stress locations observed in the model, thus supporting trivial trauma from natural head movements as a possible initiating factor in sICAD.

  1. Investigation of Ultrasound-Measured Flow Velocity, Flow Rate and Wall Shear Rate in Radial and Ulnar Arteries Using Simulation.

    Science.gov (United States)

    Zhou, Xiaowei; Xia, Chunming; Stephen, Gandy; Khan, Faisel; Corner, George A; Hoskins, Peter R; Huang, Zhihong

    2017-05-01

    Parameters of blood flow measured by ultrasound in radial and ulnar arteries, such as flow velocity, flow rate and wall shear rate, are widely used in clinical practice and clinical research. Investigation of these measurements is useful for evaluating accuracy and providing knowledge of error sources. A method for simulating the spectral Doppler ultrasound measurement process was developed with computational fluid dynamics providing flow-field data. Specific scanning factors were adjusted to investigate their influence on estimation of the maximum velocity waveform, and flow rate and wall shear rate were derived using the Womersley equation. The overestimation in maximum velocity increases greatly (peak systolic from about 10% to 30%, time-averaged from about 30% to 50%) when the beam-vessel angle is changed from 30° to 70°. The Womersley equation was able to estimate flow rate in both arteries with less than 3% error, but performed better in the radial artery (2.3% overestimation) than the ulnar artery (15.4% underestimation) in estimating wall shear rate. It is concluded that measurements of flow parameters in the radial and ulnar arteries with clinical ultrasound scanners are prone to clinically significant errors. Copyright © 2017. Published by Elsevier Inc.

  2. Cardiac and arterial elastance and myocardial wall stress in children with pectus excavatum

    Science.gov (United States)

    Akyüz Özkan, Esra; Khosrashahi, Hashem E.; Serin, Halil İbrahim; Metin, Bayram; Kılıç, Mahmut; Geçit, U. Aliye

    2016-01-01

    OBJECTIVES Pectus excavatum (PE) is one of the most common skeletal deformities of childhood. The study was undertaken to assess cardiac functions in children with PE. METHODS Echocardiography was performed on 32 children with PE and 40 age-matched healthy controls. The following parameters were monitored: meridional left ventricular (LV) wall stress (WSM), arterial elastance (Ea), LV elastance at end-systole derived by single beat (Ees(sb)), LV circumferential end-systolic wall stress (ESWSc), midwall shortening fraction (SFmid), predicted midwall fiber shortening for a measured fiber stress (midwall VCFc), myocardial fiber stress (MFS), LV end-systolic dimension (LVES), LV end-diastolic dimension (LVED) and end-systolic blood pressure (Pes), LV wall thickness at end-systole (hes). To assess the severity of PE, Haller index (HI) was calculated by computed tomography of the thorax. RESULTS SFmid, ESWSc, midwall VCFc and MFS were lower in PE children than in controls. The degree to which the parameters SFmid, ESWSc, midwall VCFc and MFS were altered in PE children was 14.9, 27.5, 20.3 and 20.3%, respectively. The minimum HI value of children with PE was 2.00, the maximum value was 4.93 and the arithmetic mean was 2.62 ± 0.56. Of the 32 children, 14 (43.75%) demonstrated mild deformity, 15 (46.88%) showed moderate and only 3 (9.37%) had severe deformity. In children with PE, there was no statistically significant correlation between the cardiac data (ESWSc, midwall VCFc, MFS, Ea, Ees(sb), LVES, LVED, Pes, hes) and HI. CONCLUSION We found ESWSc, MFS, midwall VCFc and SFmid to be lower in children with PE than in controls. We concluded that the myocardial contractility and afterload is affected in children with PE. PMID:26993478

  3. No detection of varicella-zoster virus in temporal arteries of patients with giant cell arteritis.

    Science.gov (United States)

    Muratore, Francesco; Croci, Stefania; Tamagnini, Ione; Zerbini, Alessandro; Bellafiore, Salvatore; Belloni, Lucia; Boiardi, Luigi; Bisagni, Alessandra; Pipitone, Nicolò; Parmeggiani, Maria; Cavazza, Alberto; Salvarani, Carlo

    2017-10-01

    Data on the presence of varicella-zoster virus (VZV) in temporal arteries of patients with giant cell arteritis (GCA) are controversial. We analyzed VZV infection in temporal arteries from Italian patients with temporal artery biopsy (TAB)-positive GCA, TAB-negative GCA, and controls. A total of 79 formalin-fixed, paraffin-embedded (FFPE) TABs performed between 2009 and 2012 at a single institution from 34 TAB-positive GCA patients, 15 TAB-negative GCA patients, and 30 controls were retrieved. Six 5-μm sections of all FFPE TABs were cut. The first section was analyzed by immunohistochemistry using mouse monoclonal anti-VZVgE IgG1 antibody. DNA was extracted from the remaining five sections and analyzed by real-time polymerase chain reaction (PCR) for the presence of VZV DNA. For 10 of the 34 TAB-positive GCA patients, an additional 2-mm piece of frozen TAB was available. DNA was extracted from the entire 2-mm length frozen specimen and analyzed by PCR for the presence of VZV DNA. Thirty additional 5-μm sections were cut from the FFPE TABs of these 10 patients and analyzed by immunohistochemistry for the presence of VZV antigen. Immunohistochemical analysis detected VZV antigen in 1/34 (3%) TAB-positive GCA, 0/15 TAB-negative GCA, and 0/30 controls, and in none of the 300 sections cut from the 10 FFPE TABs positive for GCA for which the frozen specimens were available. DNA obtained from all TABs was amplifiable. VZV DNA was neither found in any of the FFPE TABs nor found in frozen TABs. Our data do not support in Italian patients a possible role for VZV infection in the etiopathogenesis of GCA. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Analysis of Stress and Strain Distribution in the Artery Wall Consisted of Layers with Different Elastic Modulus and Opening Angle

    Science.gov (United States)

    Matsumoto, Takeo; Sato, Masaaki

    Bovine thoracic aorta is stiffer in the inner wall than in the outer, and its opening angle is larger in the inner layer than in the outer. A model for mechanical analysis of such a heterogeneous artery wall was developed. The wall was assumed to be made of thin, incompressible, homogeneous, and isotropic layers having different elastic properties and opening angle. Stress and strain distributions in the wall were calculated using the opening angle and stress-strain relationship measured in thin sliced layers of bovine thoracic aortas. Stress distribution was uniform under a physiological condition if elastic properties and the opening angle were set uniform. Stress distribution was not uniform under any condition when the material heterogeneity was introduced. Such non-uniformity was reduced if heterogeneity in the opening angle was considered. The opening angle may be higher in the inner wall to compensate stress concentration caused by the material heterogeneity.

  5. Aplasia Cutis Congenita Associated With Aplasia of the Superficial Temporal Artery.

    Science.gov (United States)

    Choi, Matthew Seung Suk; Choi, Jong Hwan; Ki, Sae Hwi; Jun, Yong Hoon

    2016-06-01

    Aplasia cutis congenita with or without congenital anomalies is a rare congenital disorder most commonly involving the skin of the scalp, as well as the skull and dura.The etiology is uncertain, and several theories, including vascular accident intrauterine period, vascular anomaly, intrauterine infection, teratogen, and aminiotic adhesion, have been proposed. One theory is that lesions of the scalp are usually caused by vascular anomalies.The authors report on a patient with aplasia cutis congenita presenting with a huge skin and skull defect combined with aplasia of the superficial temporal artery, which was thought to be the etiology.

  6. Successful Treatment of Two Cases of Squamous Cell Carcinoma on the Ear with Intra-Arterial Administration of Peplomycin through a Superficial Temporal Artery

    Directory of Open Access Journals (Sweden)

    Takahiro Haga

    2014-09-01

    Full Text Available Cutaneous squamous cell carcinoma (SCC is the second most common non-melanoma skin cancer and tends to develop in sun-exposed cosmetic areas, including the ear. In this report, we describe two cases of SCC on the ear successfully treated with intra-arterial administration of peplomycin through a superficial temporal artery. In addition to this selective chemotherapy, we administered oral tegafur, which achieved complete remission of the tumor. These findings suggest that intra-arterial administration of peplomycin with tegafur is one of the optimal therapies for the treatment of SCC developing on the ear.

  7. The effect of cholesterol lowering on carotid and femoral artery wall stiffness and thickness in patients with familial hypercholesterolaemia.

    Science.gov (United States)

    Smilde, T J; van den Berkmortel, F W; Wollersheim, H; van Langen, H; Kastelein, J J; Stalenhoef, A F

    2000-06-01

    Early in the process of atherosclerosis, changes in vessel wall stiffness and thickness may occur. The present study evaluates the effect of cholesterol reduction on artery wall stiffness and intima media thickness in patients with familial hypercholesterolaemia (FH). Forty-five patients with familial hypercholesterolaemia (mean age 46+/-10 years) with untreated LDL cholesterol concentration > 9 mmol L(-1), were studied before and after one year of cholesterol lowering therapy with statins (simvastatin, atorvastatin 40-80 mg day(-1). The distensibility (DC in 10-3 kPa(-1) and compliance (CC in mm2. kPa(-1) of the common carotid artery (CCA) (right and left side) and common femoral artery (CFA) (right side) were determined by a wall track system (Pie Medical). The intima media thickness (IMT) (both right and left) of the CCA, bulb (BUL), internal carotid artery (ICA) and CFA were measured in mm by high-resolution ultrasound (Biosound). The mean concentration of total cholesterol (TC), LDL-cholesterol (LDL-C) and triglycerides (TG) were reduced significantly by 43%, 51% and 25%, respectively, whereas HDL-cholesterol (HDL-C) increased by 13% (P<0.001). In the CFA, the DC and CC increased significantly (DC from 7.9+/-3.0 to 9.1+/-3.7 in 10(-3) kPa(-1); CC 0.5+/-0.2-0.6+/-0.3 in mm2. kPa(-1), whereas the DC and CC did not change in the CCA. In contrast, the IMT of the CCA decreased significantly in both men and women whereas an IMT decrease was also seen in the BUL and ICA in premenopausal women. A LDL-cholesterol reduction of 44.8% and 45.4% was necessary to induce significant decreases in IMT and increases in DC and CC. One year of cholesterol lowering therapy in FH decreases the wall stiffness in the CFA and the arterial wall thickness in the CCA.

  8. Variable-viscosity thermal hemodynamic slip flow conveying nanoparticles through a permeable-walled composite stenosed artery

    Science.gov (United States)

    Akbar, Noreen Sher; Tripathi, Dharmendra; Bég, O. Anwar

    2017-07-01

    This paper presents a mathematical model for simulating viscous, incompressible, steady-state blood flow containing copper nanoparticles and coupled heat transfer through a composite stenosed artery with permeable walls. Wall slip hydrodynamic and also thermal buoyancy effects are included. The artery is simulated as an isotropic elastic tube, following Joshi et al. (2009), and a variable viscosity formulation is employed for the flowing blood. The equations governing the transport phenomena are non-dimensionalized and the resulting boundary value problem is solved analytically in the steady state subject to physically appropriate boundary conditions. Numerical computations are conducted to quantify the effects of relevant hemodynamic, thermophysical and nanoscale parameters emerging in the model on velocity and temperature profiles, wall shear stress, impedance resistance and also streamline distributions. The model may be applicable to drug fate transport modeling with nanoparticle agents and also to the optimized design of nanoscale medical devices for diagnosing stenotic diseases in circulatory systems.

  9. Temporal hollowing and other adverse effects after lateral orbital wall decompression.

    Science.gov (United States)

    Ueland, Hans Olav; Haugen, Olav H; Rødahl, Eyvind

    2016-12-01

    To evaluate the outcome and late postoperative complications after lateral orbital wall decompression in a series of patients with thyroid eye disease (TED). One hundred and three patients operated in the period 1999-2013 were invited to participate in the study, and 84 were included after a median (range) follow-up time of 124 (13-188) months. The patients were interviewed, and preoperative and postoperative data were collected from hospital records. Photographs ('selfies') were obtained from 64 patients. Wilcoxon signed-rank test was used to evaluate the change in pre- and postoperative data. On average, visual acuity was unchanged with a median value (range) of 1.0 (0.4-1.25) before to 1.0 (0-1.25) after surgery (p = 0.5). Intraocular pressure (IOP) was reduced from a median value (range) of 17 (9-26) to 15 (8-23) mmHg (p < 0.001). Median (range) Hertel values were 23 (15-30) mm preoperatively and 20 (12-26) mm postoperatively (p < 0.001) respectively. Mean (SD) reduction in proptosis was 3.6 (±2.1) mm. Oscillopsia was reported in 24 patients (29%), 42 (50%) experienced a change in temporal sensation, and four (5%) had new-onset diplopia. In 47 patients (56%), some degree of temporal hollowing was reported. Among 64 photographed patients, 38 (59%) had noticeable hollowing on examination of postoperative pictures. There was agreement of the patient's perception of temporal hollowing and the appearance in photographs in 26 of 37 patients (70%). Lateral orbital wall decompression has been considered a safe and effective procedure for treatment of TED. Serious side-effects are infrequent, but in rare circumstances, even blindness may occur. Less serious side-effects are relatively common. Among others, a significant number of the patients developed temporal hollowing after the procedure. The patients must be informed about the possible complications before surgery. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  10. Mathematical modeling of coupled drug and drug-encapsulated nanoparticle transport in patient-specific coronary artery walls

    KAUST Repository

    Hossain, Shaolie S.

    2011-08-20

    The majority of heart attacks occur when there is a sudden rupture of atherosclerotic plaque, exposing prothrombotic emboli to coronary blood flow, forming clots that can cause blockages of the arterial lumen. Diseased arteries can be treated with drugs delivered locally to vulnerable plaques. The objective of this work was to develop a computational tool-set to support the design and analysis of a catheter-based nanoparticulate drug delivery system to treat vulnerable plaques and diffuse atherosclerosis. A threedimensional mathematical model of coupled mass transport of drug and drug-encapsulated nanoparticles was developed and solved numerically utilizing isogeometric finite element analysis. Simulations were run on a patient-specific multilayered coronary artery wall segment with a vulnerable plaque and the effect of artery and plaque inhomogeneity was analyzed. The method captured trends observed in local drug delivery and demonstrated potential for optimizing drug design parameters, including delivery location, nanoparticle surface properties, and drug release rate. © Springer-Verlag 2011.

  11. Mathematical modeling of coupled drug and drug-encapsulated nanoparticle transport in patient-specific coronary artery walls

    Science.gov (United States)

    Hossain, Shaolie S.; Hossainy, Syed F. A.; Bazilevs, Yuri; Calo, Victor M.; Hughes, Thomas J. R.

    2012-02-01

    The majority of heart attacks occur when there is a sudden rupture of atherosclerotic plaque, exposing prothrombotic emboli to coronary blood flow, forming clots that can cause blockages of the arterial lumen. Diseased arteries can be treated with drugs delivered locally to vulnerable plaques. The objective of this work was to develop a computational tool-set to support the design and analysis of a catheter-based nanoparticulate drug delivery system to treat vulnerable plaques and diffuse atherosclerosis. A three-dimensional mathematical model of coupled mass transport of drug and drug-encapsulated nanoparticles was developed and solved numerically utilizing isogeometric finite element analysis. Simulations were run on a patient-specific multilayered coronary artery wall segment with a vulnerable plaque and the effect of artery and plaque inhomogeneity was analyzed. The method captured trends observed in local drug delivery and demonstrated potential for optimizing drug design parameters, including delivery location, nanoparticle surface properties, and drug release rate.

  12. Age-related changes of wall composition and collagen cross-linking in the rat carotid artery - In relation with arterial mechanics.

    Science.gov (United States)

    Hayashi, Kozaburo; Hirayama, Emiko

    2017-01-01

    In association with age-related changes in arterial wall mechanics, the composition of connective tissues, the fraction and size of vascular smooth muscle cells (SMCs), and the degree of collagen cross-linking were studied with common carotid arteries harvested from 8, 16, 32, and 64 week-old Wistar rats. For histomorphometric studies, each arterial segment was fixed under in vivo operating force condition, and then sequentially sliced into thin specimens, followed by selective staining for the observation of collagen, elastin, and SMCs. Then, the fraction of each component, and the number and size of SMCs were determined with an image analyzer. The content of collagen and elastin, their ratio, and the number and the area fraction of SMCs showed no significant correlations with age, while the density and the size of SMCs were significantly smaller and larger, respectively, in 64 week-old animals than in the others. The results of collagen and elastin cannot explain the biomechanical data obtained in our previous study using the same animal model, which showed that the elastic modulus and wall stiffness were significantly larger in 64 week-old animals compared to younger ones. To investigate the reason for the discrepancy between the histological and the biomechanical results, a hydrothermal isometric tension method was applied to the analysis of the cross-linking of collagen, and we found that the amount of cross-links was significantly greater in 64 week-old arteries than in the others. This result corresponded well with the biomechanical results, and therefore the higher wall stiffness and elastic modulus in older arteries might be ascribed to their larger amount of collagen cross-links. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Pulsatile flow of non-Newtonian blood fluid inside stenosed arteries: Investigating the effects of viscoelastic and elastic walls, arteriosclerosis, and polycythemia diseases.

    Science.gov (United States)

    Nejad, A Abbas; Talebi, Z; Cheraghali, D; Shahbani-Zahiri, A; Norouzi, M

    2018-02-01

    In this study, the interaction of pulsatile blood flow with the viscoelastic walls of the axisymmetric artery is numerically investigated for different severities of stenosis. The geometry of artery is modeled by an axisymmetric cylindrical tube with a symmetric stenosis in a two-dimensional case. The effects of stenosis severity on the axial velocity profile, pressure distribution, streamlines, wall shear stress, and wall radial displacement for the viscoelastic artery are also compared to the elastics artery. Furthermore, the effects of atherosclerosis and polycythemia diseases on the hemodynamics and the mechanical behavior of arterial walls are investigated. The pulsatile flow of non-Newtonian blood is simulated inside the viscoelastic artery using the COMSOL Multiphysics software (version 5) and by employing the fluid-structure interaction (FSI) method and the arbitrary Lagrangian-Eulerian (ALE) method. Moreover, finite element method (FEM) is used to solve the governing equations on the unstructured grids. For modeling the non-Newtonian blood fluid and the viscoelastic arterial wall, the modified Casson model, and generalized Maxwell model are used, respectively. According to the results, with stenosis severity increasing from 25% to 75% at the time of maximum volumetric flow rate, the maximum value of axial velocity and its gradient increase 7.9 and 19.6 times, and the maximum wall shear stress of viscoelastic wall increases 24.2 times in the constriction zone. With the progression of the atherosclerosis disease (fivefold growth of arterial elastic modulus), the wall radial displacement of viscoelastic arterial walls decreases nearly 40%. In this study, axial velocity profile, pressure distribution, streamlines, wall radial displacement, and wall shear stress were examined for different percentages of stenosis (25%, 50%, and 75%). The atherosclerosis disease was investigated by the fivefold growth of viscoelastic arterial elastic modulus and polycythemia

  14. Beat-to-Beat Blood Pressure and Two-dimensional (axial and radial) Motion of the Carotid Artery Wall: Physiological Evaluation of Arterial Stiffness.

    Science.gov (United States)

    Xu, Chenchu; Xiong, Huahua; Gao, Zhifan; Liu, Xin; Zhang, Heye; Zhang, Yanping; Du, Xiuquan; Wu, Wanqing; Liu, Guotao; Li, Shuo

    2017-02-13

    The physiological relationship between local arterial displacement and blood pressure (BP) plays an integral role in assess- ment of the mechanical properties of arteries. In this study, we used more advanced methods to obtain reliable continuous BP and the displacement of the common carotid artery (CCA) simultaneously. We propose a novel evaluation method for arterial stiffness that relies on determining the physiological relationship between the axial and radial displacements of the CCA wall and beat-to-beat BP. Patients (total of 138) were divided into groups according to the following three criteria: essential hyper- tension (EH) and normotension, male and female, elderly and younger. The Pearson correlation test and canonical correlation analysis showed that the CCA indices were significantly correlated with BP indices (r = 0:787; p pressure curve showed a progressive reduction with increasing age and EH disease occurrence (EH: 0.496 vs. normotension: 0.822; age  60:0.783). Our method provides an explicit reference value and relationship for the manner in which the CCA wall responds to changes in BP. Short-term and continuous BP were significantly correlated with CCA displacement and exhibited a close inverse relationship with each subject's BP and EH, age, and systolic blood pressure.

  15. Umbilical artery intima-media and wall thickness in infants of diabetic mothers.

    Science.gov (United States)

    Sarikabadayi, Yusuf Unal; Aydemir, Ozge; Kanmaz, Gozde; Aydemir, Cumhur; Oguz, Serife Suna; Erdeve, Omer; Eyi, Elif Gul Yapar; Zergeroglu, Sema; Dilmen, Ugur

    2012-01-01

    Large for gestational age (LAG) neonates who had been exposed to an intrauterine environment of either diabetes or maternal obesity are at increased risk of developing the metabolic syndrome. This can be explained by exposure to high glucose and insulin levels in utero which alter fetal adaptation and programming. The aim of the study was to evaluate the onset of preclinical atherosclerosis in utero. We measured umbilical artery wall thickness (ruWT) in the third trimester by obstetric ultrasound and umbilical artery intima-media thickness (uIMT) in pathologic specimens of umbilical cords obtained shortly after delivery and investigated the relation between these measurements and serum insulin level and C-peptide level in cord blood and assessed insulin resistance with the homeostasis model assessment of insulin resistance (HOMA-IR) in infants of diabetic mothers (IDMs), i.e. the study group, which was divided into a large for gestational age group (LGA)-IDM group and an appropriate for gestational age group (AGA)-IDM group and compared with a control group. The LGA-IDM group had significantly higher insulin (p IDM and control groups. The LGA-IDM group had significantly larger ruWT (p = 0.013) and uIMT (p IDM and the control groups. The LGA-IDM group had increased uIMT and ruWT that correlated with the severity of maternal hyperglycemia. Measurement of ruWT in the third trimester is feasible, reproducible and strongly correlated with pathological serum insulin, C-peptide in cord blood and HOMA-IR levels. Copyright © 2012 S. Karger AG, Basel.

  16. Surgical Technique for High-Flow Internal Maxillary Artery to Middle Cerebral Artery Bypass Using a Superficial Temporal Artery Interposition Graft.

    Science.gov (United States)

    Feng, Xuequan; Meybodi, Ali Tayebi; Rincon-Torroella, Jordina; El-Sayed, Ivan H; Lawton, Michael T; Benet, Arnau

    2017-04-01

    Extracranial-to-intracranial high-flow bypass often requires cranial, cervical, and graft site incisions. The internal maxillary artery (IMA) has been proposed as a donor to decrease invasiveness, but its length is insufficient for direct intracranial bypass. We report interposition of a superficial temporal artery (STA) graft for high-flow IMA to middle cerebral artery (MCA) bypass using a middle fossa approach. To assess the feasibility of an IMA-STA graft-MCA bypass using a new middle fossa approach. Twelve specimens were studied. A 7.5-cm STA graft was obtained starting 1.5 cm below the zygomatic arch. The calibers of STA were measured. After a pterional craniotomy, the IMA was isolated inside the infratemporal fossa through a craniectomy within the lateral triangle (lateral to the posterolateral triangle) in the middle fossa and transposed for proximal end-to-end anastomosis to the STA. The Sylvian fissure was split exposing the insular segment of the MCA, and an STA-M2 end-to-side anastomosis was completed. Finally, the length of graft vessel was measured. Average diameters of the proximal and distal STA ends were 2.3 ± 0.2 and 2.0 ± 0.1 mm, respectively. At the anastomosis site, the diameter of the IMA was 2.4 ± 0.6 mm, and the MCA diameter was 2.3 ± 0.3 mm. The length of STA graft required was 56.0 ± 5.9 mm. The STA can be used as an interposition graft for high-flow IMA-MCA bypass if the STA is obtained 1.5 cm below the zygomatic arch and the IMA is harvested through the proposed approach. This procedure may provide an efficient and less invasive alternative for high-flow EC-IC bypass.

  17. Assessment of arterial wall enhancement for differentiation of parent artery disease from small artery disease: Comparison between histogram analysis and visual analysis on 3 dimensional contrast-enhanced T1-weighted turbo spin echo MR images at 3T

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jin Hee; Kim, Tae Won; Hwang, Eo Jin; Choi, Hyun Seok; Koo, Ja Seung; Shin, Yong Sam; Jung, So Lyung; Ahn, Kook Jin; Kim, Bum Soo [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2017-04-15

    The purpose of this study was to compare the histogram analysis and visual scores in 3T MRI assessment of middle cerebral arterial wall enhancement in patients with acute stroke, for the differentiation of parent artery disease (PAD) from small artery disease (SAD). Among the 82 consecutive patients in a tertiary hospital for one year, 25 patients with acute infarcts in middle cerebral artery (MCA) territory were included in this study including 15 patients with PAD and 10 patients with SAD. Three-dimensional contrast-enhanced T1-weighted turbo spin echo MR images with black-blood preparation at 3T were analyzed both qualitatively and quantitatively. The degree of MCA stenosis, and visual and histogram assessments on MCA wall enhancement were evaluated. A statistical analysis was performed to compare diagnostic accuracy between qualitative and quantitative metrics. The degree of stenosis, visual enhancement score, geometric mean (GM), and the 90th percentile (90P) value from the histogram analysis were significantly higher in PAD than in SAD (p = 0.006 for stenosis, < 0.001 for others). The receiver operating characteristic curve area of GM and 90P were 1 (95% confidence interval [CI], 0.86-1.00). A histogram analysis of a relevant arterial wall enhancement allows differentiation between PAD and SAD in patients with acute stroke within the MCA territory.

  18. Passive and Active Triaxial Wall Mechanics in a Two-Layer Model of Porcine Coronary Artery

    National Research Council Canada - National Science Library

    Yuan Lu; Hao Wu; Jiahang Li; Yanjun Gong; Jiahui Ma; Ghassan S Kassab; Yong Huo; Wenchang Tan; Yunlong Huo

    2017-01-01

    (ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) Triaxial active and passive mechanical properties of coronary arteries are needed for understanding arterial mechanics in health and disease...

  19. [Assessment of central hemodynamic properties of the arterial wall in women with previous preeclampsia].

    Science.gov (United States)

    Polónia, Jorge; Olival, Catarina; Ribeiro, Sílvia; Silva, José A; Barbosa, Loide

    2014-06-01

    We investigated viscoelastic properties of the arterial wall in women with previous preeclampsia (PE) compared to those with normal pregnancy (NP). In a cross-sectional study 45 women with previous PE and 55 with NP were included, matched for age (PE 38±6 vs. NP 38±5 years, NS) and body mass index: (PE 25±4 vs. NP 26±4 kg/m(2), NS) studied, respectively, 76±34 and 86±48 months after delivery. We assessed arterial distensibility - pulse wave velocity (PWV, Complior) and reflected waves (augmentation pressure [AP], mmHg) and augmentation index (AIx) - in the central pressure wave and blood pressure (BP) on 24-h ambulatory BP monitoring (ABPM). PE showed higher (p<0.01) peripheral systolic blood pressure (SBP): PE 131±18 vs. NP 121±19, and central SBP: PE 122±18 vs. NP 110±19 mmHg, with less amplification of central-peripheral pressure: PE 10±4 vs. NP 12±5, p=0.041, and higher (p<0.05) AP: PE 10±3 vs. NP 8±2, and AIx: PE 26±5 vs. NP 20±5 mmHg, but PE and NP did not differ in pulse wave velocity. On ABPM, PE (n=39) vs. NP (n=33) had higher nighttime SBP: PE 121±10 vs. NP 108±10 mmHg and lower percentage nocturnal SBP fall: PE 11±6 vs. NP 18±11%, both p<0.02. During follow-up, the need for antihypertensive medication was seven times higher in PE than in NP. Women with previous PE have a greater risk of hypertension, higher nighttime BP values, blunted nocturnal BP fall and changes in central pressure suggestive of increased reflected waves and peripheral vascular resistance. These factors may contribute to their higher cardiovascular risk after pregnancy. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  20. Ultrasonic Measurement of Change in Elasticity due to Endothelium Dependent Relaxation Response by Accurate Detection of Artery-Wall Boundary

    Science.gov (United States)

    Kaneko, Takuya; Hasegawa, Hideyuki; Kanai, Hiroshi

    2007-07-01

    Ross hypothesized that an endothelial dysfunction is considered to be an initial step in atherosclerosis. Endothelial cells, which release nitric oxide (NO) in response to shear stress from blood flow, have a function of relaxing smooth muscle in the media of the arterial wall. For the assessment of the endothelial function, there is a conventional method in which the change in the diameter of the brachial artery caused by flow-mediated dilation (FMD) is measured with ultrasound. However, despite the fact that the collagen-rich hard adventitia does not respond to NO, the conventional method measures the change in diameter depending on the mechanical property of the entire wall including the adventitia. Therefore, we developed a method of measuring the change in the thickness and the elasticity of the brachial artery during a cardiac cycle using the phased tracking method for the evaluation of the mechanical property of only the intima-media region. In this study, the initial positions of echoes from the lumen-intima and media-adventitia boundaries are determined using complex template matching to accurately estimate the minute change in the thickness and the elasticity of the brachial and radial arteries. The ambiguity in the determination of such boundaries was eliminated using complex template matching, and the change in elasticity measured by the proposed method was larger than the change in inner diameter obtained by the conventional method.

  1. Genetic susceptibility of the arterial wall is an important determinant of atherosclerosis in C57BL/6 and FVB/N mouse strains

    DEFF Research Database (Denmark)

    Shim, Jeong; Handberg, Aase; Östergren, Eva-Britt Caroline

    2011-01-01

    How genetic variations among inbred mouse strains translate into differences in atherosclerosis susceptibility is of significant interest for the development of new therapeutic strategies. The objective of the present study was to examine whether genetically controlled arterial wall properties in...

  2. Carotid artery wall thickness and ischemic symptoms: evaluation using multi-detector-row CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Saba, Luca; Caddeo, Giancarlo; Mallarini, Giorgio [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Radiology, Cagliari (Italy); Sanfilippo, Roberto; Montisci, Roberto [Azienda Ospedaliero Universitaria Polo di Monserrato, Department of Vascular Surgery, Cagliari (Italy); Pascalis, Luigi [Azienda Ospedaliero Universitaria Polo di Cagliari, Division of II Internal Medicine, Cagliari (Italy)

    2008-09-15

    The purpose of this study was to determine if carotid artery wall thickness (CAWT) studied by using multi-detector-row CT angiography (MDCTA) can be considered an effective parameter predictive of increased risk of stroke. A total of 217 patients were retrospectively studied by using MDCTA. In all patients CAWT was measured with an internal digital caliper. Continuous data were described as the mean value {+-} standard deviation (SD), and they were compared with Student's t-test. Scatter plots to determine interobserver agreement were performed, and correlation coefficient was calculated with Pearson statistics. A P value <0.05 was considered to mean statistical significance. Measurements of the distal common CAWT ranged from 0.5 to 1.6 mm. In the patient group without stroke, average CAWT was 0.82 mm (0.22 SD), whereas in patient group with stroke it was 1.096 mm (0.21 SD). CAWT in patients without stroke showed statistical difference (P<0.0001) when compared to patients with stroke. By using a threshold of 1 mm, an important statistical association between thick CAWT and stroke was found (P<0.0001). In fact, patients with {>=}1 mm CAWT had stroke with an odds ratio of 8.16 when compared with patients with <1 mm CAWT. Resulting data suggested that an increased CAWT is an indicator for risk of stroke. This parameter should be considered in addition to other well-known risk factors such as diabetes, hypertension, smoking, and dyslipidemia. (orig.)

  3. Mechanobiology of low-density lipoprotein transport within an arterial wall--impact of hyperthermia and coupling effects.

    Science.gov (United States)

    Chung, Stephen; Vafai, Kambiz

    2014-01-03

    The effects of hyperthermia, coupling attributes and property variations on Low-density lipoprotein (LDL) transport within a multi-layered wall while accounting for the fluid structure interaction (FSI) is analyzed in this work. To understand the potential impact of the hyperthermia process, thermo-induced attributes are incorporated, accounting for the plasma flow, mass transfer, as well as the elastic wall structure. The coupling effect of osmotic pressure, Soret and Dufour diffusion is discussed and their influence on LDL transport is examined, demonstrating that only the Soret effect needs to be accounted for. The effect of thermal expansion on changing the behavior of flow, mass transport, and elastic structure is illustrated and analyzed while incorporating the variations in the effective LDL diffusivity and consumption rate, as well as other dominating parameters. It is shown that hyperthermia results in an enhancement in LDL transport by increasing the concentration levels within the arterial wall. © 2013 Elsevier Ltd. All rights reserved.

  4. Hemodynamic analysis in an idealized artery tree: differences in wall shear stress between Newtonian and non-Newtonian blood models.

    Directory of Open Access Journals (Sweden)

    Jared C Weddell

    Full Text Available Development of many conditions and disorders, such as atherosclerosis and stroke, are dependent upon hemodynamic forces. To accurately predict and prevent these conditions and disorders hemodynamic forces must be properly mapped. Here we compare a shear-rate dependent fluid (SDF constitutive model, based on the works by Yasuda et al in 1981, against a Newtonian model of blood. We verify our stabilized finite element numerical method with the benchmark lid-driven cavity flow problem. Numerical simulations show that the Newtonian model gives similar velocity profiles in the 2-dimensional cavity given different height and width dimensions, given the same Reynolds number. Conversely, the SDF model gave dissimilar velocity profiles, differing from the Newtonian velocity profiles by up to 25% in velocity magnitudes. This difference can affect estimation in platelet distribution within blood vessels or magnetic nanoparticle delivery. Wall shear stress (WSS is an important quantity involved in vascular remodeling through integrin and adhesion molecule mechanotransduction. The SDF model gave a 7.3-fold greater WSS than the Newtonian model at the top of the 3-dimensional cavity. The SDF model gave a 37.7-fold greater WSS than the Newtonian model at artery walls located immediately after bifurcations in the idealized femoral artery tree. The pressure drop across arteries reveals arterial sections highly resistive to flow which correlates with stenosis formation. Numerical simulations give the pressure drop across the idealized femoral artery tree with the SDF model which is approximately 2.3-fold higher than with the Newtonian model. In atherosclerotic lesion models, the SDF model gives over 1 Pa higher WSS than the Newtonian model, a difference correlated with over twice as many adherent monocytes to endothelial cells from the Newtonian model compared to the SDF model.

  5. Engineering temporal accumulation of a low recalcitrance polysaccharide leads to increased C6 sugar content in plant cell walls

    Energy Technology Data Exchange (ETDEWEB)

    Vega-Sánchez, Miguel E. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Loqué, Dominique [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Lao, Jeemeng [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Catena, Michela [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Verhertbruggen, Yves [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Herter, Thomas [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Yang, Fan [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Harholt, Jesper [Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C Denmark; Ebert, Berit [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg C Denmark; Baidoo, Edward E. K. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Keasling, Jay D. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Department of Chemical and Biomolecular Engineering, and Department of Bioengineering, University of California, Berkeley CA USA; Scheller, Henrik V. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Department of Plant and Microbial Biology, University of California, Berkeley CA USA; Heazlewood, Joshua L. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Ronald, Pamela C. [Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley CA USA; Department of Plant Pathology and the Genome Center, University of California, Davis CA USA

    2015-01-14

    Reduced cell wall recalcitrance and increased C6 monosaccharide content are desirable traits for future biofuel crops, as long as these biomass modifications do not significantly alter normal growth and development. Mixed-linkage glucan (MLG), a cell wall polysaccharide only present in grasses and related species among flowering plants, is comprised of glucose monomers linked by both β-1,3 and β-1,4 bonds. Previous data have shown that constitutive production of MLG in barley (Hordeum vulgare) severely compromises growth and development. Here, we used spatio-temporal strategies to engineer Arabidopsis thaliana plants to accumulate significant amounts of MLG in the cell wall by expressing the rice CslF6 MLG synthase using secondary cell wall and senescence-associated promoters. Results using secondary wall promoters were suboptimal. When the rice MLG synthase was expressed under the control of a senescence-associated promoter, we obtained up to four times more glucose in the matrix cell wall fraction and up to a 42% increase in saccharification compared to control lines. Importantly, these plants grew and developed normally. The induction of MLG deposition at senescence correlated with an increase of gluconic acid in cell wall extracts of transgenic plants in contrast to the other approaches presented in this study. MLG produced in Arabidopsis has an altered structure compared to the grass glucan, which likely affects its solubility, while its molecular size is unaffected. The induction of cell wall polysaccharide biosynthesis in senescing tissues offers a novel engineering alternative to enhance cell wall properties of lignocellulosic biofuel crops.

  6. Low concentrations of lithium and cyclooxygenase inhibitors enhance endothelin-1 (ET-1)-induced contractions in human temporal artery, but not in porcine ophthalmic artery.

    Science.gov (United States)

    Bakken, I J; Vincent, M B; White, L R; Cappelen, J; Skaanes, K O; Sjaastad, O

    1992-11-01

    Endothelins are a recently discovered group of potent vasoconstrictor peptides synthesized by endothelial cells and other tissues in various species, which seem to participate in the regulation of vascular tonus. Abnormalities in vasoactivity in the head may be an important event in headache pathophysiology, although the mechanisms responsible for such constrictions and/or dilations are not known. The endothelium and its constrictor peptide, endothelin, may play a key role in such mechanisms. Of the various drugs used in the treatment of headache, lithium is an accepted treatment for cluster headache, and indomethacin is the drug of choice for the associated condition chronic paroxysmal hemicrania. The mechanism of action of these drugs in these headaches is not known. Due to the possible involvement of endothelin in headache disorders, the objective of this study was to verify the effects of lithium and cyclooxygenase inhibitors (indomethacin, acetylsalicylic acid and naproxen) on endothelin-1 (ET-1)-induced contractions in isolated human temporal arteries and porcine ophthalmic arteries. It was found that all drugs increased the (ET-1)-induced contractions in human temporal arteries. Conversely, there were no significant changes induced by the drugs in porcine ophthalmic arteries. These results are consistent with the variation of activity often seen in different vascular beds and between species. The potential importance of such reactions for the understanding of vascular changes putatively involved in headache development and treatment is discussed.

  7. Oxidized Phospholipids on Lipoprotein(a) Elicit Arterial Wall Inflammation and an Inflammatory Monocyte Response in Humans.

    Science.gov (United States)

    van der Valk, Fleur M; Bekkering, Siroon; Kroon, Jeffrey; Yeang, Calvin; Van den Bossche, Jan; van Buul, Jaap D; Ravandi, Amir; Nederveen, Aart J; Verberne, Hein J; Scipione, Corey; Nieuwdorp, Max; Joosten, Leo A B; Netea, Mihai G; Koschinsky, Marlys L; Witztum, Joseph L; Tsimikas, Sotirios; Riksen, Niels P; Stroes, Erik S G

    2016-08-23

    Elevated lipoprotein(a) [Lp(a)] is a prevalent, independent cardiovascular risk factor, but the underlying mechanisms responsible for its pathogenicity are poorly defined. Because Lp(a) is the prominent carrier of proinflammatory oxidized phospholipids (OxPLs), part of its atherothrombosis might be mediated through this pathway. In vivo imaging techniques including magnetic resonance imaging, (18)F-fluorodeoxyglucose uptake positron emission tomography/computed tomography and single-photon emission computed tomography/computed tomography were used to measure subsequently atherosclerotic burden, arterial wall inflammation, and monocyte trafficking to the arterial wall. Ex vivo analysis of monocytes was performed with fluorescence-activated cell sorter analysis, inflammatory stimulation assays, and transendothelial migration assays. In vitro studies of the pathophysiology of Lp(a) on monocytes were performed with an in vitro model for trained immunity. We show that subjects with elevated Lp(a) (108 mg/dL [50-195 mg/dL]; n=30) have increased arterial inflammation and enhanced peripheral blood mononuclear cells trafficking to the arterial wall compared with subjects with normal Lp(a) (7 mg/dL [2-28 mg/dL]; n=30). In addition, monocytes isolated from subjects with elevated Lp(a) remain in a long-lasting primed state, as evidenced by an increased capacity to transmigrate and produce proinflammatory cytokines on stimulation (n=15). In vitro studies show that Lp(a) contains OxPL and augments the proinflammatory response in monocytes derived from healthy control subjects (n=6). This effect was markedly attenuated by inactivating OxPL on Lp(a) or removing OxPL on apolipoprotein(a). These findings demonstrate that Lp(a) induces monocyte trafficking to the arterial wall and mediates proinflammatory responses through its OxPL content. These findings provide a novel mechanism by which Lp(a) mediates cardiovascular disease. URL: http://www.trialregister.nl. Unique identifier: NTR

  8. Carotid and femoral artery wall thickness and stiffness in patients at risk for cardiovascular disease, with special emphasis on hyperhomocysteinemia.

    Science.gov (United States)

    Smilde, T J; van den Berkmortel, F W; Boers, G H; Wollersheim, H; de Boo, T; van Langen, H; Stalenhoef, A F

    1998-12-01

    Recent developments in ultrasound technology enable the noninvasive measurement of structural and functional vessel wall changes. Until now, the effect of homocysteine on the arterial wall has remained unclear: reports on intima-media thickness (IMT) yield conflicting results, whereas data on vessel wall stiffness are lacking. Because several cardiovascular risk factors result in an increased IMT or stiffness, different groups at risk for atherosclerotic disease, with special emphasis on hyperhomocysteinemia, were studied. Nineteen patients homozygous and 14 subjects heterozygous for cystathionine beta-synthase (CBS) deficiency, 21 patients with familial hypercholesterolemia (FH), 15 patients with essential hypertension, 20 smokers, and 28 control subjects were studied. The IMT values (both right and left) of the common carotid artery (CCA), bulb (BUL), internal carotid artery (ICA), and common femoral artery (CFA) were measured in millimeters by high-resolution ultrasound (Biosound). The distensibility (DC, in 10(-3). kPa-1) and compliance (CC in mm2. kPa-1) coefficients of the CCA (right and left) and CFA (right) were determined by a wall track system (Pie Medical). The mean IMT of the posterior wall in the CCA was 0.70+/-0.09 mm in healthy controls. For patients with vascular disease, FH, and hypertension and in smokers, the mean CCA IMT was larger, whereas no major differences in IMT were observed in patients either homozygous or heterozygous for CBS deficiency. The DC and CC in the right CCA were 23.5+/-6.9 (10(-3). kPa-1) and 0.9+/-0.3 (mm2. kPa-1) in healthy subjects, slightly lower in patients homozygous for CBS deficiency, and clearly lower in patients with vascular disease, FH, and hypertension. No positive correlation was found between plasma homocysteine level and either IMT, CC, or DC. Because smoking was a confounder in each risk group, a stepwise regression analysis was carried out to assess the contribution of each risk factor on IMT and arterial

  9. Arterial wall metabolism in experimental hypertension of coarctation of the aorta of short duration

    Science.gov (United States)

    Hollander, William; Kramsch, Dieter M.; Farmelant, Melvin; Madoff, Irving M.

    1968-01-01

    Coarctation of the mid-thoracic aorata was surgically produced in mongrel dogs which were sacrificed from 4-12 wk after the operation. As compared to the findings in control animals, the sodium, chloride, and water content of the hypetensive portion of the coarcted thoracic aorta was significantly elevated, whereas the electrolyte and water content of the relatively normotensive portion of the coarcted aorta was normal. The sodium, potassium, and water content of the pulmonary artery, skeletal muscle, and cardiac muscle of the coarcted dog was not altered. These observations suggest that an elevated arterial pressure may influence the electrolyte and water composition of the arteries. The arterial pressure also may influence the content and synthesis of acid mucopolysaccharides (MPS) in the arteries since the content of sulfated MPS and the incorporation of injected radiosulfate into sulfated MPS were significantly increased in the hypertensive portion of the coarcted thoracic aorta but were significantly reduced in the relatively normotensive (“hypotensive”) portion of the coarcted aorta. The observed increase in MPS may have been a factor directly responsible for the increase in the sodium content of the hypertensive aorta since MPS can act as polyelectrolytes and bind cations. Although the arterial pressure may influence certain metabolic functions in the arteries, it did not appear to have a direct effect on the arterial lipids since the lipid content of the hypertensive and of the relatively normotensive portions of the coarcted aorta were comparable to the values found in the normal aorta. Images PMID:5645864

  10. High incidence of ICA anterior wall aneurysms in patients with an anomalous origin of the ophthalmic artery: possible relevance to the pathogenesis of aneurysm formation.

    Science.gov (United States)

    Indo, Masahiro; Oya, Soichi; Tanaka, Michihiro; Matsui, Toru

    2014-01-01

    Surgery for aneurysms at the anterior wall of the internal carotid artery (ICA), which are also referred to as ICA anterior wall aneurysms, is often challenging. A treatment strategy needs to be determined according to the pathology of the aneurysm-namely, whether the aneurysm is a saccular aneurysm with firm neck walls that would tolerate clipping or coiling, a dissecting aneurysm, or a blood blister-like aneurysm. However, it is not always possible to properly evaluate the condition of the aneurysm before surgery solely based on angiographic findings. The authors focused on the location of the ophthalmic artery (OA) in determining the pathology of ICA anterior wall aneurysms. Between January 2006 and December 2012, diagnostic cerebral angiography, for any reason, was performed on 1643 ICAs in 855 patients at Saitama Medical Center. The authors also investigated the relationship between the origin of the OA and the incidence of ICA anterior wall aneurysms. The pathogenesis was also evaluated for each aneurysm based on findings from both angiography and open surgery to identify any correlation between the location where the OA originated and the conditions of the aneurysm walls. Among 1643 ICAs, 31 arteries (1.89%) were accompanied by an anomalous origin of the OA, including 26 OAs originating from the C3 portion, 3 originating from the C4 portion, and 2 originating from the anterior cerebral artery. The incidence of an anomalous origin of the OA had no relationship to age, sex, or side. Internal carotid artery anterior wall aneurysms were observed in 16 (0.97%) of 1643 ICAs. Female patients had a significantly higher risk of having ICA anterior wall aneurysms (p = 0.026). The risk of ICA anterior wall aneurysm formation was approximately 50 times higher in patients with an anomalous origin of the OA (25.8% [8 of 31]) than in those with a normal OA (0.5% [8 of 1612], p ICA anterior wall aneurysms underwent craniotomies. Based on the intraoperative findings, all 6

  11. In vivo assessment of pulmonary arterial wall fibrosis by intravascular optical coherence tomography in pulmonary arterial hypertension: a new prognostic marker of adverse clinical follow-up.

    Science.gov (United States)

    Domingo, Enric; Grignola, Juan C; Aguilar, Rio; Montero, María Angeles; Arredondo, Christian; Vázquez, Manuel; López-Messeguer, Manuel; Bravo, Carlos; Bouteldja, Nadia; Hidalgo, Cristina; Roman, Antonio

    2013-01-01

    The aim is to correlate pulmonary arterial (PA) remodeling estimated by PA fibrosis in PA hypertension (PAH) with clinical follow-up. Histology of PA specimens is also performed. 19 patients, aged 54±16 (4 men), functional class II-III were studied with right heart catheterization, PA Intravascular Ultrasound and optical coherence tomography (OCT) in inferior lobe segment. PA wall fibrosis was obtained by OCT ( area of fibrosis/PA cross sectional area × 100). Patients follow-up was blind to OCT. Events were defined as mortality, lung transplantation, need of intravenous prostaglandins or onset of right ventricular failure. OCT measurements showed high intra- and interobserver agreement. There was a good correlation between OCT and histology in PA fibrosis from explanted lungs. Area of fibrosis was 1.4±0.8 mm(2), % fibrosis was 22.3±8. Follow-up was 3.5 years (2.5-4.5). OCT %Fib was significantly correlated with PA capacitance (r=-0.536) and with pulmonary vascular rsistance (r=0.55). Patients were divided according to the median value of PA fibrosis. There were 10 patients with a high (≥ 22%) and 9 with a low fibrosis (right heart failure) out of 10 patients with high and in 0 out of 9 patients with low fibrosis (p<0.01). In PAH, the severity of PA remodeling assessed by OCT wall fibrosis was significantly predictive of severely unfavorable clinical outcome. In vivo assessment of pulmonary arterial wall fibrosis by intravascular OCT in PAH is a promising new prognostic marker of adverse clinical outcome.

  12. Assessment of Arterial Wall Enhancement for Differentiation of Parent Artery Disease from Small Artery Disease: Comparison between Histogram Analysis and Visual Analysis on 3-Dimensional Contrast-Enhanced T1-Weighted Turbo Spin Echo MR Images at 3T.

    Science.gov (United States)

    Jang, Jinhee; Kim, Tae-Won; Hwang, Eo-Jin; Choi, Hyun Seok; Koo, Jaseong; Shin, Yong Sam; Jung, So-Lyung; Ahn, Kook-Jin; Kim, Bum-Soo

    2017-01-01

    The purpose of this study was to compare the histogram analysis and visual scores in 3T MRI assessment of middle cerebral arterial wall enhancement in patients with acute stroke, for the differentiation of parent artery disease (PAD) from small artery disease (SAD). Among the 82 consecutive patients in a tertiary hospital for one year, 25 patients with acute infarcts in middle cerebral artery (MCA) territory were included in this study including 15 patients with PAD and 10 patients with SAD. Three-dimensional contrast-enhanced T1-weighted turbo spin echo MR images with black-blood preparation at 3T were analyzed both qualitatively and quantitatively. The degree of MCA stenosis, and visual and histogram assessments on MCA wall enhancement were evaluated. A statistical analysis was performed to compare diagnostic accuracy between qualitative and quantitative metrics. The degree of stenosis, visual enhancement score, geometric mean (GM), and the 90th percentile (90P) value from the histogram analysis were significantly higher in PAD than in SAD (p = 0.006 for stenosis, enhancement allows differentiation between PAD and SAD in patients with acute stroke within the MCA territory.

  13. Arterial bending angle and wall morphology correlate with slow coronary flow: Determination with multidetector CT coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kantarci, Mecit, E-mail: akkanrad@hotmail.com [Department of Radiology, Medical Faculty, Atatuerk University, Erzurum (Turkey); Guendogdu, Fuat [Department of Cardiology, Medical Faculty, Atatuerk University, Erzurum (Turkey); Doganay, Selim [Department of Radiology, Medical Faculty, Erciyes University, Kayseri (Turkey); Duran, Cihan [Department of Radiology, Bilim University, Florence Nightingale Hospital, Istanbul (Turkey); Kalkan, M. Emin [Department of Cardiology, Medical Faculty, Atatuerk University, Erzurum (Turkey); Sagsoz, M. Erdem [Department of Radiology, Medical Faculty, Atatuerk University, Erzurum (Turkey); Kucuk, Osman [Department of Electronic Engineering, Engineering Faculty, Atatuerk University, Erzurum (Turkey); Karakaya, Afak [Department of Radiology, Medical Faculty, Atatuerk University, Erzurum (Turkey); Kucuk, Ahmet [Department of Mathematics, Science Faculty, Atatuerk University, Erzurum (Turkey); Akguen, Metin [Department of Chest, Medical Faculty, Atatuerk University, Erzurum (Turkey)

    2011-01-15

    Background and purpose: The purpose of this study was to assess angulations and vessel wall morphology that could lead to bending head loss in the RCA and LMCA arteries of patients with slow coronary flow (SCF) evaluated by MDCT coronary angiography. Methods: The study involved 51 patients (45 males, mean age: 59.6 years) who were diagnosed with SCF by coronary angiography. Diagnosis of SCF was based on thrombolysis in myocardial infarction (TIMI) frame count. Fifty-one patients with absence of slow flow were selected as the control group. The angulations of the main coronary arteries with the aorta were measured from the axial images obtained through MDCT coronary angiography, and the findings were recorded. In addition, the coronary artery walls of these patients were evaluated. For statistical analysis, SPSS for Windows 10.0 (SPSS Inc., Chicago, IL) was used. For comparisons of the angles, either independent samples t test or the Mann-Whitney U test was used where appropriate. Results: The results of the study indicated that 38 patients had SCF in the LAD. Comparisons of patients with SCF with the controls revealed that in the patients with SCF, the mean angle of the LMCA with the aorta (40.9 {+-} 20.5{sup o}) was statistically significantly smaller than the mean angle of the LMCA with the aorta in the control cases (71.8 {+-} 11{sup o}). In 12 patients, slow flow was detected in the RCA. Those with slow flow in the RCA had significantly smaller angles (mean: 33.2 {+-} 20.4{sup o}) than the other cases (mean: 78.9 {+-} 10.7{sup o}). Conclusion: A small angle of origin of the main coronary arteries from the aorta, measured on MDCT examinations is correlated with slow blood flow in those vessels, as calculated by the TIMI frame count in catheter coronary angiography.

  14. Entropy Generation Analysis in Convective Ferromagnetic Nano Blood Flow Through a Composite Stenosed Arteries with Permeable Wall

    Science.gov (United States)

    Sher Akbar, Noreen; Wahid Butt, Adil

    2017-05-01

    The study of heat transfer is of significant importance in many biological and biomedical industry problems. This investigation comprises of the study of entropy generation analysis of the blood flow in the arteries with permeable walls. The convection through the flow is studied with compliments to the entropy generation. Governing problem is formulized and solved for low Reynold’s number and long wavelength approximations. Exact analytical solutions have been obtained and are analyzed graphically. It is seen that temperature for pure water is lower as compared to the copper water. It gains magnitude with an increase in the slip parameter.

  15. Temporal artery biopsy in the diagnosis of giant cell arteritis: Bigger is not always better.

    Science.gov (United States)

    Papadakis, Marios; Kaptanis, Sarantos; Kokkori-Steinbrecher, Aikaterini; Floros, Nikolaos; Schuster, Frauke; Hübner, Gunnar

    2017-09-01

    Accurate early giant cell arteritis (GCA) diagnosis can be established through temporal artery biopsy (TAB). We herein investigate the relationship between specimen length and positive TAB result in a tertiary-care hospital in Germany during a 8-year period. Secondarily, we studied the relationships of specific epidemiological and laboratory parameters with positive TABs. We retrospectively reviewed the medical records of all patients with suspected GCA, who underwent TAB in our institution. The total sample consisted of 116 patients with a mean age of 76.1 (SD 7.7) years. Mean specimen length post-fixation was 0.94 cm (SD 0.49). The TAB(+) group consisted of 64 patients (55.2%). The specimen length was comparable in the two groups (0.96 cm vs 0.91 cm, p = 0.581). Twenty six TAB(+) patients (41%) had a post-fixation specimen longer than 1 cm, comparable with the respective percentage in the TAB(-) group (42%, p = 1). All laboratory tests performed were statistically significantly different in the two groups. We conclude that TAB length is not associated with the TAB diagnostic yield in patients with clinical suspicion of GCA. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Do the cardiovascular risk profile and the degree of arterial wall calcification influence the performance of MDCT angiography of lower extremity arteries?

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, B.C.; Werncke, T.; Foert, E.; Ribbe, C.; Wolf, K.J. [Charite-University Medicine, Department of Radiology and Nuclear Medicine, Berlin (Germany); Kruschewski, M. [Charite-University Medicine, Department of Surgery, Berlin (Germany); Hopfenmueller, W. [Charite-University Medicine, Department of Biometry and Clinical Epidemiology, Berlin (Germany); Albrecht, T. [Charite-University Medicine, Department of Radiology and Nuclear Medicine, Berlin (Germany); Vivantes Klinikum Neukoelln, Department of Radiology and Interventional Therapy, Berlin (Germany)

    2010-02-15

    To retrospectively assess the influence of arterial wall calcifications on the accuracy of run-off computed tomographic angiography (CTA) and to analyse whether cardiovascular risk factors are predictors of compromising calcifications. In 200 consecutive patients who underwent run-off CTA, calcifications were assessed in pelvic, thigh and calf arteries using a four-point scale. Fifty-nine patients with digital subtraction angiography (DSA) were assessed by both techniques to estimate a threshold of compromising calcifications, defined as a decrease of sensitivity, specificity, PPV or NPV below the lower 95% confidence interval of overall results. Regression analysis was performed to investigate a potential relationship between compromising calcifications and presence of cardiovascular risk factors, advanced patient age and severe peripheral arterial disease (PAD). The highest Ca{sup ++}-score was chosen as the cut-off for the regression analysis, as a relevant decrease of specificity (0.91; overall: 0.95) above the knee and of sensitivity (0.66; overall: 0.83), specificity (0.65; overall: 0.93), positive predictive value (PPV) and negative predictive value (NPV) below the knee was observed. In the pelvic and thigh arteries, severe PAD (Fontaine Stage {>=}III) showed the highest odds ratio for compromising calcifications (2.9), followed by diabetes mellitus (2.4), renal failure (2.1) and smoking (1.7). In the calf, renal failure (12.2) and diabetes mellitus (3.3) were the strongest predictors. Patients with diabetes and renal failure should be considered as candidates for alternative vessel imaging in order to avoid inconclusive examination results. (orig.)

  17. Computerized flow and vessel wall analyses of coronary arteries for detection of non-calcified plaques in coronary CT angiography

    Science.gov (United States)

    Wei, Jun; Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Agarwal, Prachi; Hadjiiski, Lubomir; Kazerooni, Ella

    2016-03-01

    The buildup of non-calcified plaques (NCP) that are vulnerable to rupture in coronary arteries is a risk for myocardial infarction. We are developing a computer-aided detection (CADe) system to assist radiologists in detecting NCPs in cCTA. A major challenge of NCP detection is the large number of false positives (FPs) caused by the small sized coronary arteries, image noise and artifacts. In this study, our purpose is to design new image features to reduce FPs. A data set of 98 cCTA scans was retrospectively collected from patient files. We first used vessel wall analysis, in which topological features were extracted from vessel wall and fused with a support-vector machine, to identify the NCP candidates from the segmented coronary tree. Computerized flow dynamic (CFD) features that characterize the change in blood flow due to the presence of plaques and a vascular cross-sectional (VCS) feature that quantifies the presence of low attenuation region at the vessel wall were designed for FP reduction. Using a leave-one-out resampling method, a support vector machine classifier was trained to merge the features into a NCP likelihood score using the vessel wall features alone or in combination with the new CDF and VCS features. The performance of the new features in classification of true NCPs and FPs was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). Without the new CFD and VCS features, the test AUC was 0.84+/-0.01. The AUC was improved to 0.88+/-0.01 with the addition of the new features. The improvement was statistically significant (p < 0.001). The study indicated that the new flow dynamic and vascular cross-sectional features were useful for differentiation of NCPs from FPs in cCTA.

  18. Management of middle meningeal and superficial temporal artery hemorrhage from total temporomandibular joint replacement surgery with a gelatin-based hemostatic agent.

    Science.gov (United States)

    Cillo, Joseph E; Sinn, Douglas; Truelson, John M

    2005-03-01

    Complications associated with temporomandibular joint (TMJ) replacement surgery may include injury to nerves, blood vessels, and otologic structures. Vascular injuries can be associated with trauma to the carotid artery and its terminal branches, the superficial temporal artery, and the internal maxillary artery. Suggested management to control hemorrhage has included uniand bipolar electrocautery, laser ablation, local anesthetics with vasoconstrictors, direct pressure, embolization, and ligation. In this case report, the iatrogenic injury to both the middle meningeal and superficial temporal arteries during total TMJ replacement surgery controlled by using a gelatin-based hemostatic agent is discussed.

  19. Extremal states of energy of a double-layered thick-walled tube - application to residually stressed arteries.

    Science.gov (United States)

    Waffenschmidt, Tobias; Menzel, Andreas

    2014-01-01

    Various biological tissues are designed to optimally support external loads for complex geometries and mechanobiological structures. This results in complex microstructures of such materials. The design of, for instance, (healthy) arteries, which are in the focus of this work, is characterised by a residually stressed fibre-reinforced multi-layered composite with highly non-linear elastic response. The complex interaction of material properties with the geometry and residual stress effects enables the optimal support under different blood pressures, respectively blood flow, within the vessel. The fibres reinforcing the arterial wall, as well as residual stresses present in the vessel, strongly influence its overall behaviour and performance. Turn-over and remodelling processes of the collagenous fibres occurring in the respective layers - either resulting from natural growth phenomena or from artificially induced changes in loading condition such as stent deployment - support the optimisation of the multi-layered composite structure of arteries for the particular loading conditions present in the artery. Within this contribution, the overall energetic properties of an artery are discussed by means of the inflation, bending and extension of a double-layered cylindrical tube. Different states of residual stresses and different fibre orientations are considered so that, for instance, representative fibre angles that result in extremal states of the total potential energy can be identified. In view of turn-over and remodelling processes, these orientations are considered to constitute preferred directions of fibre alignment. In summary, the main goal of this work is to calculate optimal material, structural and loading parameters by concepts of energy-minimisation. Several numerical studies show that the obtained values - such as the fibre orientations, the residual axial stretch and the opening angle - are in good agreement with respective physiological parameters

  20. Relationship between heart rate variability, blood pressure and arterial wall properties during air and oxygen breathing in healthy subjects.

    Science.gov (United States)

    Graff, Beata; Szyndler, Anna; Czechowicz, Krzysztof; Kucharska, Wiesława; Graff, Grzegorz; Boutouyrie, Pierre; Laurent, Stephane; Narkiewicz, Krzysztof

    2013-11-01

    Previous studies reported that normobaric hyperoxia influences heart rate, arterial pressure, cardiac output and systemic vascular resistance, but the mechanisms underlying these changes are still not fully understood. Several factors are considered including degeneration of endothelium-derived nitric oxide by reactive oxygen species, the impact of oxygen-free radicals on tissues and alterations of autonomic nervous system function. Recently, new devices for the detailed non-invasive assessment of large and small arteries have been developed. Therefore, the aim of our study was to assess heart rate variability (HRV) as a potential indicator of autonomic balance and its relation to blood pressure and vascular properties during medical air (MAB) and 100% oxygen breathing (OXB) in healthy volunteers. In 12 healthy subjects we assessed heart rate and blood pressure variability, baroreflex sensitivity, respiratory frequency, common carotid artery diameter and its wall distensibility, as well as changes in the digital artery pulse waveform, stroke index and systemic vascular resistance during MAB and OXB. Mean and systolic blood pressure have increased significantly while digital pulse amplitude and carotid artery diameter were significantly lower during hyperoxia. Heart rate variability measures did not differ during MAB and OXB. However, the correlations between spectral HRV components and those hemodynamic parameters which have changed due to hyperoxia varied substantially during MAB (correlated significantly) and OXB (no significant correlations were noted). Our findings suggest that autonomic nervous system might not be the main mediator of the cardiovascular changes during 100% oxygen breathing in healthy subjects. It seems that the direct vascular responses are initial consequences of hyperoxia and other cardiovascular parameter alterations are secondary to them. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Baroreflex sensitivity of an arterial wall during rotary blood pump assistance.

    Science.gov (United States)

    Yambe, Tomoyuki; Imachi, Kou; Shiraishi, Yasuyuki; Yamaguchi, Tasuku; Shibata, Mune-Ichi; Kameyama, Takeshi; Yoshizawa, Makoto; Sugita, Norihiro

    2009-09-01

    It is well known that the baroreflex system is one of the most important indicators of the pathophysiology in hypertensive patients. We can check the sensitivity of the baroreflex by observing heart rate (HR) responses; however, there is no simple diagnostic method to measure the arterial behavior in the baroreflex system. Presently, we report the development of a method and associated hardware that enables the diagnosis of baroreflex sensitivity by measuring the responses of both the heart and the artery. In this system, the measurements are obtained by monitoring an electrocardiogram and a pulse wave recorded from the radial artery or fingertip. The arterial responses were measured in terms of the pulse wave velocity (PWV) calculated from the pulse wave transmission time (PTT) from the heart to the artery. In this system, the HR change corresponding to the blood pressure change in time series sequence was observed. Slope of the changes in blood pressure and HR indicated the sensitivity of the baroreflex system of the heart. This system could also measure the sensitivity of the baroreflex system of an artery. Changes in the PWV in response to the blood pressure changes were observed. Significant correlation was observed in the time sequence between blood pressure change and PWV change after calculating the delay time by cross-correlation. The slope of these parameter changes was easily obtained and it demonstrated the sensitivity of the baroreflex system of an artery. We evaluated this method in animal experiments using rotary blood pump (RBP) with undulation pump ventricular assist device, and PTT elongation was observed in response to increased blood pressure with RBP assistance. Furthermore, when tested clinically, decreased sensitivity of the baroreflex system in hypertensive patients was observed. This system may be useful when we consider the ideal treatment and follow-up of patients with hypertension.

  2. Right ventricular free-wall longitudinal speckle tracking strain in patients with pulmonary arterial hypertension under specific treatment.

    Science.gov (United States)

    Kemal, Hatice S; Kayikcioglu, Meral; Kultursay, Hakan; Vuran, Ozcan; Nalbantgil, Sanem; Mogulkoc, Nesrin; Can, Levent

    2017-04-01

    Right ventricular (RV) dysfunction is a major determinant of outcomes in patients with pulmonary arterial hypertension (PAH), although the optimal measure of RV function is poorly defined. We evaluated the utility of RV free-wall speckle tracking strain as an assessment tool for RV function in patients with PAH who are already under specific treatment compared with conventional echocardiographic parameters and investigated the relationship of RV free-wall strain with clinical hemodynamic parameters of RV performance. Right ventricular free-wall strain was evaluated in 92 patients (Group-1 and Group-4 pulmonary hypertension) who were on PAH-specific treatment for at least 3 months. Right atrial (RA) area, RV FAC, TAPSE, tricuspid S, functional class, 6-minute walking distance, and NT-proBNP were studied. The mean duration of follow-up was 222±133 days. All patients were under PAH-specific treatment, and mean RV free-wall strain was -13.16±6.3%. RV free-wall strain correlated well with functional class (r=.312, P=.01), NT-proBNP (r=.423, P=.0001), RA area (r=.427, P=.0001), FAC (r=-.637, P=.0001), TAPSE (r=-.524, P=.0001), tricuspid S (r=-.450, P=.0001), 6-minute walking distance (r=-.333, P=.002). RV free-wall strain significantly correlated with all follow-up adverse events, death, and clinical right heart failure (RHF) (P=.04, P=.03, P=.02, respectively). According to the receiver operator characteristic analysis, the cutoff value for RV free-wall strain for the development of clinical RHF was -12.5% (sensitivity: 71%, specificity: 67%) and for all cardiovascular adverse events (death included) was -12.5% (sensitivity: 54%, specificity: 64%). Assessment of RV free-wall strain is a feasible, easy-to-perform method and may be used as a predictor of RHF, clinical deterioration, and mortality in patients already under PAH-specific treatment. © 2017, Wiley Periodicals, Inc.

  3. Noninvasive detection of coronary artery wall thickening with age in healthy subjects using high resolution MRI with beat-to-beat respiratory motion correction.

    Science.gov (United States)

    Scott, Andrew D; Keegan, Jennifer; Mohiaddin, Raad H; Firmin, David N

    2011-10-01

    To demonstrate coronary artery wall thickening with age in a small healthy cohort using a highly efficient, reliable, and reproducible high-resolution MR technique. A 3D cross-sectional MR vessel wall images (0.7 × 0.7 × 3 mm resolution) with retrospective beat-to-beat respiratory motion correction (B2B-RMC) were obtained in the proximal right coronary artery of 21 healthy subjects (age, 22-62 years) with no known cardiovascular disease. Lumen and outer wall (lumen + vessel wall) areas were measured in one central slice from each subject and average wall thickness and wall area/outer wall area ratio (W/OW) calculated. Imaging was successful in 18 (86%) subjects with average respiratory efficiency 99.3 ± 1.7%. Coronary vessel wall thickness and W/OW significantly correlate with subject age, increasing by 0.088 mm and 0.031 per decade respectively (R = 0.53, P = 0.024 and R = 0.48, P = 0.046). No relationship was found between lumen area and vessel wall thickness (P = NS), but outer wall area increased significantly with vessel wall thickness at 19 mm(2) per mm (P = 0.046). This is consistent with outward vessel wall remodeling. Despite the small size of our healthy cohort, using high-resolution MR imaging and B2B-RMC, we have demonstrated increasing coronary vessel wall thickness and W/OW with age. The results obtained are consistent with outward vessel wall remodeling. Copyright © 2011 Wiley-Liss, Inc.

  4. Comparison of Kalman-filter-based approaches for block matching in arterial wall motion analysis from B-mode ultrasound

    Science.gov (United States)

    Gastounioti, A.; Golemati, S.; Stoitsis, J.; Nikita, K. S.

    2011-11-01

    Block matching (BM) has been previously used to estimate motion of the carotid artery from B-mode ultrasound image sequences. In this paper, Kalman filtering (KF) was incorporated in this conventional method in two distinct scenarios: (a) as an adaptive strategy, by renewing the reference block and (b) by renewing the displacements estimated by BM or adaptive BM. All methods resulting from combinations of BM and KF with the two scenarios were evaluated on synthetic image sequences by computing the warping index, defined as the mean squared error between the real and estimated displacements. Adaptive BM, followed by an update through the second scenario at the end of tracking, ABM_KF-K2, minimized the warping index and yielded average displacement error reductions of 24% with respect to BM. The same method decreased estimation bias and jitter over varying center frequencies by 30% and 64%, respectively, with respect to BM. These results demonstrated the increased accuracy and robustness of ABM_KF-K2 in motion tracking of the arterial wall from B-mode ultrasound images, which is crucial in the study of mechanical properties of normal and diseased arterial segments.

  5. Genetic variation within the Y chromosome is not associated with histological characteristics of the atherosclerotic carotid artery or aneurysmal wall.

    Science.gov (United States)

    Haitjema, Saskia; van Setten, Jessica; Eales, James; van der Laan, Sander W; Gandin, Ilaria; de Vries, Jean-Paul P M; de Borst, Gert J; Pasterkamp, Gerard; Asselbergs, Folkert W; Charchar, Fadi J; Wilson, James F; de Jager, Saskia C A; Tomaszewski, Maciej; den Ruijter, Hester M

    2017-04-01

    Haplogroup I, a common European paternal lineage of the Y chromosome, is associated with increased risk of coronary artery disease in British men. It is unclear whether this haplogroup or any other haplogroup on the Y chromosome is associated with histological characteristics of the diseased vessel wall in other vascular manifestations of cardiovascular diseases showing a male preponderance. We examined Dutch men undergoing either carotid endarterectomy from the Athero-Express biobank (AE, n = 1217) or open aneurysm repair from the Aneurysm-Express biobank (AAA, n = 393). Upon resolving the Y chromosome phylogeny, each man was assigned to one of the paternal lineages based on combinations of single nucleotide polymorphisms of the male-specific region of the Y chromosome. We examined the associations between the Y chromosome and the histological characteristics of the carotid plaque and aneurysm wall, including lipid content, leukocyte infiltration and intraplaque haemorrhage, in all men. A majority of men were carriers of either haplogroup I (AE: 28% AAA: 24%) or haplogroup R (AE: 59% AAA: 61%). We found no association between Y chromosomal haplogroups and histological characteristics of plaque collected from carotid arteries or tissue specimens of aneurysms. Moreover, the distribution of frequency for all Y chromosomal haplogroups in both cohorts was similar to that of a general population of Dutch men. Our data show that genetic variation on the Y chromosome is not associated with histological characteristics of the plaques from carotid arteries or specimens of aneurysms in men of Dutch origin. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Detection of vessel wall calcifications in vertebral arteries using susceptibility weighted imaging

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Lisa C.; Boeker, Sarah M.; Bender, Yvonne Y.; Fallenberg, Eva M.; Wagner, Moritz; Hamm, Bernd; Makowski, Marcus R. [Department of Radiology, Charite, Berlin (Germany); Liebig, Thomas [Department of Neuroradiology, Charite, Berlin (Germany)

    2017-09-15

    Calcification of the brain supplying arteries has been linked to an increased risk for cerebrovascular disease. The purpose of this study was to test the potential of susceptibility weighted MR imaging (SWMR) for the detection of vertebral artery calcifications, based on CT as a reference standard. Four hundred seventy-four patients, who had received head CT and 1.5 T MR scans with SWMR, including the distal vertebral artery, between January 2014 and December 2016, were retrospectively evaluated and 389 patients were included. Sensitivity and specificity for the detection of focal calcifications and intra- and interobserver agreement were calculated for SWMR and standard MRI, using CT as a standard of reference. The diameter of vertebral artery calcifications was used to assess correlations between imaging modalities. Furthermore, the degree of vessel stenosis was determined in 30 patients, who had received an additional angiography. On CT scans, 40 patients showed a total of 52 vertebral artery calcifications. While SWMR reached a sensitivity of 94% (95% CI 84-99%) and a specificity of 97% (95% CI 94-98%), standard MRI yielded a sensitivity of 33% (95% CI 20-46%), and a specificity of 93% (95% CI 90-96%). Linear regression analysis of size measurements confirmed a close correlation between SWMR and CT measurements (R {sup 2} = 0.74, p < 0.001). Compared to standard MRI (ICC = 0.52; CI 0.45-0.59), SWMR showed a higher interobserver agreement for calcification measurements (ICC = 0.84; CI 0.81-0.87). For detection of distal vertebral artery calcifications, SWMR demonstrates a performance comparable to CT and considerably higher than conventional MRI. (orig.)

  7. Evaluation of vascular wall elasticity of human digital arteries using alternating current-signal photoplethysmography

    Directory of Open Access Journals (Sweden)

    Uangpairoj P

    2013-06-01

    Full Text Available Pichitra Uangpairoj, Masahiro Shibata Department of Bioscience and Engineering, Shibaura Institute of Technology, Saitama, Japan Purpose: A simple method of estimating arterial elasticity in the human finger using a volume-oscillometric technique with photoplethysmography was principally studied under the various effects of age, sex, and cold-stress stimulation for testing the capability of using this technique in arterial elasticity analysis. Methods: Amplitude variations in the alternating current signal of the photoplethysmograph during a continuous change in transmural pressure were analyzed to obtain the blood pressure and the transmural pressure–relative volume difference relationship of the arteries. We first tested the effect of the occluding cuff size on the arterial elasticity analysis in eight subjects (ages 20–45 years to obtain a suitable cuff size, resulting in the selection of a middle cuff with a 22 mm diameter. Blood pressure and arterial elasticity were measured in six groups of subjects separated into three age-groups of women and men (ages 20–25, 32–45, and over 50 years for testing the effect of age and sex. Twelve subjects (ages 20–25 years also had their blood pressure and arterial elasticity measured in three conditions under the influence of the cold-stress stimulation. Results: Age, sex, and cold-stress stimulation had an impact on mean blood pressure (P < 0.0005, 0.025, whereas pulse pressure and heart rate were statistically unchanged by those factors. Furthermore, an advanced age (over 50 years was found to induce an increase in relative volume difference values (P <0.025 and upward shifting of the transmural pressure–relative volume difference relationships, whereas sex, level of mean blood pressure, and cold-stress stimulation had no influence on these forms of the index. Conclusion: This study showed the usefulness of the relative volume difference as being a mean blood pressure-independent indicator

  8. Breast arterial calcification and risk of carotid atherosclerosis: Focusing on the preferentially affected layer of the vessel wall

    Energy Technology Data Exchange (ETDEWEB)

    Sedighi, Nahid, E-mail: nsedighi@sina.tums.ac.ir [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of); Radmard, Amir Reza, E-mail: radmard@ams.ac.ir [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of); Radmehr, Ali, E-mail: radmehr@sina.tums.ac.ir [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of); Hashemi, Pari, E-mail: phtums@yahoo.com [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of); Hajizadeh, Abdolmahmoud, E-mail: mroomezi@yahoo.com [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of); Taheri, Amir Pejman Hashemi, E-mail: hashemip@sina.tums.ac.ir [Department of Radiology, Shariati Hospital, Tehran University of Medical Sciences. North Kargar Ave., Tehran 14114 (Iran, Islamic Republic of)

    2011-08-15

    Objective: To assess the relationship between breast arterial calcification (BAC) detected on screening mammography and atherosclerosis of carotid arteries considering the most likely involved layer of the arterial wall. Materials and methods: A total of 537 consecutive women who underwent screening mammography were enrolled in this study. Seventy-nine subjects having BAC, aged 46-75 years, and 125 age-matched controls from those without BAC were selected for ultrasound examination of carotid arteries assessing intima-media thickness (IMT) and plaque presence. Participants were divided into three groups of risk including, low-risk: IMT < 0.6 mm without plaque, medium-risk: 0.6 mm {<=} IMT {<=} 0.8 mm without plaque and high-risk: IMT > 0.8 mm and/or plaque. Risk factors for atherosclerosis were obtained from medical records for independent effects. Results: BAC was present in 14.7% of mammograms. According to multivariable logistic regression analyses, significant association was identified between the carotid atherosclerosis risk and presence of BAC. Compared to women with IMT < 0.6 mm, those with 0.6 mm {<=} IMT{<=} 0.8 mm and IMT > 0.8 mm had OR (95% CI) of 4.88 (1.47-16.16) and 23.36 (4.54-120.14), respectively. The OR (95% CI) for carotid plaque was 3.13 (1.3-7.57). There was no interaction between IMT category and plaque. Significant associations were also detected with postmenopausal duration (P = 0.02) and hypertension (P = 0.004). Conclusion: The risk of carotid atherosclerosis increases with the presence of BAC. Women with BAC are more likely to have thicker IMT than plaque, which could be attributed to the preferentially similar affected layer of media causing thick IMT rather than plaque.

  9. CORRELATIONS OF DIFFERENT STRUCTURAL AND FUNCTIONAL CHARACTERISTICS OF ARTERIAL WALL WITH TRADITIONAL CARDIOVASCULAR RISK FACTORS IN HEALTHY PEOPLE OF DIFFERENT AGE. PART 2

    Directory of Open Access Journals (Sweden)

    I. D. Strazhesko

    2016-01-01

    Full Text Available Detection of principal subclinical arterial wall lesions is one of the most important aspects of effective cardiovascular disease (CVD primary prevention. Such lesions include: arterial wall thickening, increased rigidity, endothelial dysfunction development. However, the role of traditional CVD risk factors in the development of individual arterial wall lesions in CVD-free people is understudied. This is particularly so with people of older age. Aim. To study the role of traditional CVD risk factors in development of arterial wall lesions in relatively healthy individuals of different age. Material and methods. We have examined a total of 303 people aged 25-91 years, with no signs of CVD and other chronic diseases and without any regular medical treatment. Anthropometric parameters, blood pressure, fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides levels were detected in all the patients. Measurement of pulse wave velocity was conducted using SphygmoCor device (AtCorMedical,Australia. Carotid ultrasound to measure intima-media thickness and number of atherosclerotic plaques was conducted using linear transducer with ultra-high resolution 17-5 MHz (PHILIPS iU22, the Netherlands in the B-mode. Endothelium-dependent vasodilation was assessed by the reactive hyperemia test. Results. Multivariate linear regression analysis has revealed fasting hyperglycemia and increased systolic blood pressure to be to a greater degree associated with arterial wall state in both age groups. According to the results of multivariate logistic regression analysis a relationship between risk factors and arterial wall parameters is stronger in the younger group as compared with the older one. Conclusion. Systolic blood pressure and fasting hyperglycemia must be the main targets of CVD primary prevention in older age group, while in younger age group other traditional risk factors must be

  10. CORRELATIONS OF DIFFERENT STRUCTURAL AND FUNCTIONAL CHARACTERISTICS OF ARTERIAL WALL WITH TRADITIONAL CARDIOVASCULAR RISK FACTORS IN HEALTHY PEOPLE OF DIFFERENT AGE. PART 1

    Directory of Open Access Journals (Sweden)

    I. D. Strazhesko

    2016-01-01

    Full Text Available Arterial wall status is determined by several characteristics, the main of them are as follows: pulse wave velocity (PWV, carotid arteries intima-media thickness (IMT, the presence of atherosclerotic plaques, endothelium-dependent vasodilation (EDVD. When these parameters change, the risk for cardiovascular disease (CVD grows. The nature of relationship between these indices in people without CVD clinical signs is understudied, especially in those of older age.Aim. To estimate correlations between different parameters of arterial wall in patients of different age without CVD.Material and methods. A total of 303 people aged 25-91 years without any manifestations of CVD or other chronic diseases and without regular medical treatment were examined. PWV estimation, carotid ultrasound with IMT measurement and atherosclerotic plaques amount calculation and EDVD estimation using reactive hyperemia test were performed. Results. Patients without CVD clinical signs rather often reveal arterial wall lesions already in the younger age group (mean age 40.9±8.7: reduced EDVD – in 26% of the cases, the presence of atherosclerotic plaques – in 22%, increased PWV – in 15%, increased IMT – in 8%. The prevalence of arterial wall alterations in the older age group (mean age 61.19±8.5 increase many-fold. All arterial wall parameters correlate with age. The stronger correlation was revealed between IMT and the amount of atherosclerotic plaques: r=0.46 (р<0.001 in the younger group and r=0.47 (р<0.001 in the older one. We didn’t find any relationship between PWV and EDVD in the younger group and between PWV and the amount of atherosclerotic plaques in the older one. Thickened carotid intima-media increases the risk of arterial stiffness by 2.3 times.Conclusion. Estimation of the state of arterial wall in people of young age without CVD allows detecting individuals who require active CVD prevention. Increased stiffness of arterial wall and the development

  11. wall

    Directory of Open Access Journals (Sweden)

    Irshad Kashif

    2016-01-01

    Full Text Available Maintaining indoor climatic conditions of buildings compatible with the occupant comfort by consuming minimum energy, especially in a tropical climate becomes a challenging problem for researchers. This paper aims to investigate this problem by evaluating the effect of different kind of Photovoltaic Trombe wall system (PV-TW on thermal comfort, energy consumption and CO2 emission. A detailed simulation model of a single room building integrated with PV-TW was modelled using TRNSYS software. Results show that 14-35% PMV index and 26-38% PPD index reduces as system shifted from SPV-TW to DGPV-TW as compared to normal buildings. Thermal comfort indexes (PMV and PPD lie in the recommended range of ASHARE for both DPV-TW and DGPV-TW except for the few months when RH%, solar radiation intensity and ambient temperature were high. Moreover PVTW system significantly reduces energy consumption and CO2 emission of the building and also 2-4.8 °C of temperature differences between indoor and outdoor climate of building was examined.

  12. Optimizing the imaging protocol for vivo coronary artery wall using high-resolution MIRI: An experimental study on porcine and human

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jiang; Li, Tao; Cul, Xiaoming; Zhou, Weihua; Zhang, Xinwu [The General Hospital of Chinese People' s Armed Police Forces, Beijing (China)

    2013-08-15

    To optimize the MR imaging protocol for coronary arterial wall depiction in vitro and characterize the coronary atherosclerotic plaques. MRI examination was prospectively performed in ten porcine hearts in order to optimize the MR imaging protocol. Various surface coils were used for coronary arterial wall imaging with the same parameters. Then, the image parameters were further optimized for high-resolution coronary wall imaging. The signal-noise ratio (SNR) and contrast-noise ratio (CNR) of images were measured. Finally, 8 human cadaver hearts with coronary atherosclerotic plaques were prospectively performed with MRI examination using optimized protocol in order to characterize the coronary atherosclerotic plaques. The SNR and CNR of MR image with temporomandibular coil were the highest of various surface coils. High-resolution and high SNR and CNR for ex vivo coronary artery wall depiction can be achieved using temporomandibular coil with 512 x 512 in matrix. Compared with histopathology, the sensitivity and specificity of MRI for identifying advanced plaques were: type IV-V (lipid, necrosis, fibrosis), 94% and 95%; type VI (hemorrhage), 100% and 98%; type VII (calcification), 91% and 100%; and type VIII (fibrosis without lipid core), 100% and 98%, respectively. Temporomandibular coil appears to be dramatically superior to eight-channel head coil and knee coil for ex vivo coronary artery wall imaging, providing higher spatial resolution and improved the SNR. Ex vivo high-resolution MRI has capability to distinguish human coronary atherosclerotic plaque compositions and accurately classify advanced plaques.

  13. The Temporal Relationship between Arterial Stiffening and Blood Pressure Is Modified by Methotrexate Treatment in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Richard J. Woodman

    2017-08-01

    Full Text Available Background: The temporal relationship between arterial stiffness and blood pressure (BP may vary depending on age and other clinical and demographic factors. Since both BP and arterial stiffness are also affected by inflammatory processes, we examined the temporal arterial stiffness-BP relationship in patients with rheumatoid arthritis (RA treated with either methotrexate (MTX, an anti-rheumatic agent shown to reduce cardiovascular risk in meta-analyses, or other disease-modifying anti-rheumatic drugs (DMARDs.Methods: Measurements of clinic and 24-h peripheral and central systolic and diastolic BP (SBP and DBP, and pulse wave velocity (PWV were assessed in RA patients on stable treatment with either MTX ± other DMARDs (MTX group, n = 41, age 61 ± 14 years, 73% females or other DMARDs (non-MTX group, n = 18, age 65 ± 13 years, 89% females. Measurements were performed at baseline and after 8 months. The temporal relationships were examined using cross-lagged path analysis with models that included age, sex, body mass index, prednisolone, and folic acid use and 28-joint disease activity score.Results: There were significant differences in the temporal arterial stiffness-BP relationships between those in the MTX and DMARD groups. A higher PWV at baseline caused a significant increase in 6 out of 8 different measures of SBP at 8 months amongst those treated with DMARDs (standardized β, range = 0.54–0.66, p < 0.003 for each and 3 out of 8 different measures of DBP (standardized β, range = 0.52–0.61, p < 0.003 for each but was not associated with either SBP or DBP at 8 months amongst those treated with MTX. The difference in the effect of baseline PWV on 8-month BP between the 2 groups was also significant (p < 0.003 for 4 measures including clinic peripheral SBP (β = 7.0, 95% CI = 2.8–11.1 mmHg per 1 m/s higher baseline PWV; p < 0.001.Conclusions: Higher arterial stiffness preceded increases in BP in subjects with RA treated with DMARDs

  14. Volumetric Arterial Wall Shear Stress Calculation Based on Cine Phase Contrast MRI

    NARCIS (Netherlands)

    Potters, Wouter V.; van Ooij, Pim; Marquering, Henk; VanBavel, Ed; Nederveen, Aart J.

    2015-01-01

    PurposeTo assess the accuracy and precision of a volumetric wall shear stress (WSS) calculation method applied to cine phase contrast magnetic resonance imaging (PC-MRI) data. Materials and MethodsVolumetric WSS vectors were calculated in software phantoms. WSS algorithm parameters were optimized

  15. Heterogeneity and weak coupling may explain the synchronization characteristics of cells in the arterial wall

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Aalkjær, Christian; Matchkov, Vladimir V

    2008-01-01

    development of force known as vasomotion. We present experimental data showing a considerable heterogeneity in cellular calcium dynamics in the vascular wall. In stimulated vessels, some SMCs remain quiescent, whereas others display waves of variable frequency. At the onset of vasomotion, all SMCs...... synchronization also requires a high-conductance pathway that provides strong coupling between the cells....

  16. Acute absolute vasodilatation is associated with a lower vascular wall stiffness in pulmonary arterial hypertension.

    Science.gov (United States)

    Grignola, Juan C; Domingo, Enric; Aguilar, Rio; Vázquez, Manuel; López-Messeguer, Manuel; Bravo, Carlos; Roman, Antonio

    2013-04-05

    Acute vasoreactivity testing (VT) is considered mandatory in the diagnostic work-up of patients with pulmonary arterial hypertension (PAH). We studied the relation between the acute absolute arterial vasodilatation and the severity of vascular remodeling estimated by intravascular ultrasound (IVUS) in patients with idiopathic PAH. Simultaneous right heart catheterization and IVUS of the pulmonary artery (PA) were performed both in basal conditions and during short-term intravenous epoprostenol infusion in nineteen idiopathic PAH patients. Pulmonary vascular resistance (PVRi) and capacitance indexes (stroke volume/pulse pressure, Cp), were calculated. Local pulsatility was estimated by IVUS (IVUSp) (systolic-diastolic lumen area/diastolic lumen area×100; sA-dA/dA) and PA stiffness was assessed by the elastic modulus (E: pulse pressure/IVUSp). Epoprostenol infusion (11±2ng/kg/min) determined a real vasodilatation (increment of dA>10%) in six patients. This vasodilation group presented on average significantly higher cardiac index, stroke volume index and Cp, and lower PVRi and IVUSp (Prights reserved.

  17. Quantifying [{sup 18}F]fluorodeoxyglucose uptake in the arterial wall: the effects of dual time-point imaging and partial volume effect correction

    Energy Technology Data Exchange (ETDEWEB)

    Blomberg, Bjoern A. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark); Bashyam, Arjun; Ramachandran, Abhinay; Gholami, Saeid; Houshmand, Sina; Salavati, Ali; Werner, Tom; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zaidi, Habib [Geneva University Hospital, Division of Nuclear Medicine and Molecular Imaging, Geneva (Switzerland); University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands)

    2015-08-15

    The human arterial wall is smaller than the spatial resolution of current positron emission tomographs. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake. We evaluated the impact of a novel method for partial volume effect (PVE) correction with contrast-enhanced CT (CECT) assistance on quantification of arterial wall {sup 18}F-FDG uptake at different imaging time-points. Ten subjects were assessed by CECT imaging and dual time-point PET/CT imaging at approximately 60 and 180 min after {sup 18}F-FDG administration. For both time-points, uptake of {sup 18}F-FDG was determined in the aortic wall by calculating the blood pool-corrected maximum standardized uptake value (cSUV{sub MAX}) and cSUV{sub MEAN}. The PVE-corrected SUV{sub MEAN} (pvcSUV{sub MEAN}) was also calculated using {sup 18}F-FDG PET/CT and CECT images. Finally, corresponding target-to-background ratios (TBR) were calculated. At 60 min, pvcSUV{sub MEAN} was on average 3.1 times greater than cSUV{sub MAX} (P <.0001) and 8.5 times greater than cSUV{sub MEAN} (P <.0001). At 180 min, pvcSUV{sub MEAN} was on average 2.6 times greater than cSUV{sub MAX} (P <.0001) and 6.6 times greater than cSUV{sub MEAN} (P <.0001). This study demonstrated that CECT-assisted PVE correction significantly influences quantification of arterial wall {sup 18}F-FDG uptake. Therefore, partial volume effects should be considered when quantifying arterial wall {sup 18}F-FDG uptake with PET. (orig.)

  18. A model of smooth muscle cell synchronization in the arterial wall

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian; Aalkjær, Christian; Nilsson, Holger

    2007-01-01

    . The simulated results point to a permissive role of cyclic guanosine monophosphate (cGMP) in establishing intercellular synchronization. In sufficient concentration, cGMP may activate a cGMP-sensitive calcium-dependent chloride channel causing a tight spatio-temporal coupling between release of sarcoplasmic...

  19. Obesity-related pulmonary arterial hypertension in rats correlates with increased circulating inflammatory cytokines and lipids and with oxidant damage in the arterial wall but not with hypoxia

    Science.gov (United States)

    Irwin, David C.; Garat, Chrystelle V.; Crossno, Joseph T.; MacLean, Paul S.; Sullivan, Timothy M.; Erickson, Paul F.; Jackman, Matthew R.; Harral, Julie W.; Reusch, Jane E. B.

    2014-01-01

    Abstract Obesity is causally linked to a number of comorbidities, including cardiovascular disease, diabetes, renal dysfunction, and cancer. Obesity has also been linked to pulmonary disorders, including pulmonary arterial hypertension (PAH). It was long believed that obesity-related PAH was the result of hypoventilation and hypoxia due to the increased mechanical load of excess body fat. However, in recent years it has been proposed that the metabolic and inflammatory disturbances of obesity may also play a role in the development of PAH. To determine whether PAH develops in obese rats in the absence of hypoxia, we assessed pulmonary hemodynamics and pulmonary artery (PA) structure in the diet-resistant/diet-induced obesity (DR/DIO) and Zucker lean/fatty rat models. We found that high-fat feeding (DR/DIO) or overfeeding (Zucker) elicited PA remodeling, neomuscularization of distal arterioles, and elevated PA pressure, accompanied by right ventricular (RV) hypertrophy. PA thickening and distal neomuscularization were also observed in DIO rats on a low-fat diet. No evidence of hypoventilation or chronic hypoxia was detected in either model, nor was there a correlation between blood glucose or insulin levels and PAH. However, circulating inflammatory cytokine levels were increased with high-fat feeding or calorie overload, and hyperlipidemia and oxidant damage in the PA wall correlated with PAH in the DR/DIO model. We conclude that hyperlipidemia and peripheral inflammation correlate with the development of PAH in obese subjects. Obesity-related inflammation may predispose to PAH even in the absence of hypoxia. PMID:25610600

  20. Association between histological features in temporal artery biopsies and clinical features of patients with giant cell arteritis.

    Science.gov (United States)

    Breuer, Gabriel S; Nesher, Ronit; Reinus, Konstantin; Nesher, Gideon

    2013-06-01

    In most cases of giant cell arteritis (GCA) the diagnosis is confirmed by temporal artery biopsy. Aside from the diagnostic purpose, histological parameters may serve as prognostic markers. To review positive temporal artery biopsies ofGCA in an attempt to correlate various histological parameters with clinical features, disease complications and outcome. Positive biopsies from 65 GCA patients were randomly selected for review by a single pathologist. In each biopsy the following parameters were scored: intensity and location of the inflammatory infiltrate, presence of giant cells and other cell types, fragmentation and calcification of the internal elastic lamina, intimal thickening, and presence of luminal thrombus. Clinical data were obtained from the patients' charts. Intensity of the initial systemic inflammatory reaction (ISIR) at the time of diagnosis was scored by the presence of five parameters: fever, anemia, thrombocytosis, leukocytosis, and sedimentation rate >100 mm/hr. In cases with bilateral positive biopsy (n=27), there was good correlation between the two sides regarding intensity of inflammation (r= 0.65, P< 0.001), location of the infiltrate (r= 0.7, P< 0.001), degree of intimal thickening (r= 0.54, P 0.001), and presence of giant cells (r= 0.83, P< 0.001). The rate of corticosteroid discontinuation tended to be quicker in patients with inflammatory infiltrates confined mainly to the adventitia, but other histological parameters did not affect this rate. Inflammatory infiltrates confined to the adventitia were associated with more neuro-ophthalmic ischemic manifestations, weak/moderate ISIR at the time of diagnosis, and faster rate of corticosteroid discontinuation. No association was found between other temporal artery biopsy histological parameters and clinical features of GCA patients.

  1. Influence of Fixed Combination of Metformin SR and Glimepiride on Carbohydrate, Lipid Metabolism and Arterial Wall Stiffness in Patients with Diabetes Mellitus Type 2

    Directory of Open Access Journals (Sweden)

    O.S. Larin

    2015-06-01

    Conclusions. Combined hypoglycemic therapy with glimepiride and metformin SR for 12 weeks resulted in a statistically significant improvement of carbohydrate and lipid metabolism, had no effect on anthropometric parameters and the total amount of adipose tissue, prevented the progression of arteriosclerosis of large vessels according to the indicators of arterial wall stiffness.

  2. A two-layered suspension (particle-fluid) model for non-Newtonian fluid flow in a catheterized arterial stenosis with slip condition at the wall of stenosed artery

    Science.gov (United States)

    Ponalagusamy, R.

    2017-05-01

    The primary concern of the present investigation is to study blood flow in a porous catheterized artery with an axially asymmetric and radially symmetric stenosis (constriction). In the present study, blood is characterized as a two-fluid system containing a cell-rich zone of suspension of blood cells described to be a particle-fluid suspension (Jeffrey fluid) and a cell-free plasma (Newtonian fluid) layer near the wall. The systematic expressions for flow characteristics such as fluid phase and particle phase velocities, flow rate, wall shear stress, resistive force, and frictional forces on walls of arterial stenosis and catheter are derived. It is recorded that the wall shear stress, flow resistance, and frictional forces are found to be increased with catheter size, red cell concentration, and slip parameter. When blood obeys the law of constitutive equation of a Jeffrey fluid, the flowing blood experiences lesser wall shear stress, flow resistance and frictional forces as compared to the case of blood being categorized as a Newtonian fluid. The increase in Darcy number, blood rheology as Jeffrey fluid, and the presence of peripheral plasma layer near the wall serves to reduce substantially the values of the flow characteristics (wall shear stress, flow resistance and frictional forces).

  3. The development and optimisation of 3D black-blood R2* mapping of the carotid artery wall.

    Science.gov (United States)

    Yuan, Jianmin; Graves, Martin J; Patterson, Andrew J; Priest, Andrew N; Ruetten, Pascal P R; Usman, Ammara; Gillard, Jonathan H

    2017-12-01

    To develop and optimise a 3D black-blood R2* mapping sequence for imaging the carotid artery wall, using optimal blood suppression and k-space view ordering. Two different blood suppression preparation methods were used; Delay Alternating with Nutation for Tailored Excitation (DANTE) and improved Motion Sensitive Driven Equilibrium (iMSDE) were each combined with a three-dimensional (3D) multi-echo Fast Spoiled GRadient echo (ME-FSPGR) readout. Three different k-space view-order designs: Radial Fan-beam Encoding Ordering (RFEO), Distance-Determined Encoding Ordering (DDEO) and Centric Phase Encoding Order (CPEO) were investigated. The sequences were evaluated through Bloch simulation and in a cohort of twenty volunteers. The vessel wall Signal-to-Noise Ratio (SNR), Contrast-to-Noise Ratio (CNR) and R2*, and the sternocleidomastoid muscle R2* were measured and compared. Different numbers of acquisitions-per-shot (APS) were evaluated to further optimise the effectiveness of blood suppression. All sequences resulted in comparable R2* measurements to a conventional, i.e. non-blood suppressed sequence in the sternocleidomastoid muscle of the volunteers. Both Bloch simulations and volunteer data showed that DANTE has a higher signal intensity and results in a higher image SNR than iMSDE. Blood suppression efficiency was not significantly different when using different k-space view orders. Smaller APS achieved better blood suppression. The use of blood-suppression preparation methods does not affect the measurement of R2*. DANTE prepared ME-FSPGR sequence with a small number of acquisitions-per-shot can provide high quality black-blood R2* measurements of the carotid vessel wall. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Thermochemoradiation Therapy Using Superselective Intra-arterial Infusion via Superficial Temporal and Occipital Arteries for Oral Cancer With N3 Cervical Lymph Node Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Mitsudo, Kenji, E-mail: mitsudo@yokohama-cu.ac.jp [Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama (Japan); Koizumi, Toshiyuki; Iida, Masaki; Iwai, Toshinori; Oguri, Senri [Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama (Japan); Yamamoto, Noriyuki [Department of Oral and Maxillofacial Surgery, Nagoya University Graduate School of Medicine, Nagoya (Japan); Itoh, Yoshiyuki [Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Kioi, Mitomu; Hirota, Makoto; Tohnai, Iwai [Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama (Japan)

    2012-08-01

    Purpose: To evaluate the therapeutic results and histopathological effects of treatment with thermochemoradiation therapy using superselective intra-arterial infusion via the superficial temporal and occipital arteries for N3 cervical lymph node metastases of advanced oral cancer. Methods and Materials: Between April 2005 and September 2010, 9 patients with N3 cervical lymph node metastases of oral squamous cell carcinoma underwent thermochemoradiation therapy using superselective intra-arterial infusion with docetaxel (DOC) and cisplatin (CDDP). Treatment consisted of hyperthermia (2-8 sessions), superselective intra-arterial infusions (DOC, total 40-60 mg/m{sup 2}; CDDP, total 100-150 mg/m{sup 2}) and daily concurrent radiation therapy (total, 40-60 Gy) for 4-6 weeks. Results: Six of 9 patients underwent neck dissection 5-8 weeks after treatment. In four of these 6 patients, all metastatic lymph nodes, including those at N3, were grade 3 (non-viable tumor cells present) or grade 4 (no tumor cells present) tumors, as classified by the system by Shimosato et al (Shimosato et al Jpn J Clin Oncol 1971;1:19-35). In 2 of these 6 patients, the metastatic lymph nodes were grade 2b (destruction of tumor structures with a small amount of residual viable tumor cells). The other 3 patients did not undergo neck dissection due to distant metastasis after completion of thermochemoradiation therapy (n=2) and refusal (n=1). The patient who refused neck dissection underwent biopsy of the N3 lymph node and primary sites and showed grade 3 cancer. During follow-up, 5 patients were alive without disease, and 4 patients died due to pulmonary metastasis (n=3) and noncancer-related causes (n=1). Five-year survival and locoregional control rates were 51% and 88%, respectively. Conclusions: Thermochemoradiation therapy using intra-arterial infusion provided good histopathologic effects and locoregional control rates in patients with N3 metastatic lymph nodes. However, patients with N3

  5. Direct Anastomosis Using Occipital Artery for Additional Revascularization in Moyamoya Disease After Combined Superficial Temporal Artery-Middle Cerebral Artery and Indirect Bypass.

    Science.gov (United States)

    Kazumata, Ken; Kamiyama, Hiroyasu; Saito, Hisayasu; Maruichi, Katsuhiko; Ito, Masaki; Uchino, Haruto; Nakayama, Naoki; Kuroda, Satoshi; Houkin, Kiyohiro

    2017-04-01

    The posterior cerebral artery (PCA) is involved in approximately 30% of moyamoya disease (MMD) cases. However, there have been insufficient reports describing revascularization techniques in the posterior portion of the brain, particularly of direct anastomosis. To perform a technical assessment in patients with MMD who underwent either occipital artery (OA)-PCA bypass or OA-middle cerebral artery (MCA) bypass. A total of 428 revascularization procedures in 368 patients were retrospectively assessed by reviewing clinical charts and radiological data. Ten patients (3.5%) were treated with direct bypass after the anterior revascularization with a median interval of 30 months (range, 5 months-16 years). Seven patients were bypass and in 8 hemispheres with an OA-PCA bypass. Patency of the direct bypass was confirmed on angiogram in 7 of 7 patients who underwent conventional angiogram performed within 1 year after the surgery. None of the 10 patients demonstrated cerebral infarctions after the posterior revascularization. In MMD, symptomatic PCA regression after anterior revascularization was found predominantly in children and young adults. Direct anastomosis in the posterior portion of the brain can be successfully achieved and is effective in preventing ischemic events.

  6. Assessment of influence of traditional cardiovascular risk factors and inflammation on arterial wall structural characteristics in psoriatic arthritis

    Directory of Open Access Journals (Sweden)

    T V Korotaeva

    2009-01-01

    Full Text Available Assessment of influence of traditional cardiovascular risk factors and inflammation on arterial wall structural characteristics in psoriatic arthritis. Objective. To assess possibility of traditional cardiovascular risk (CVR factors application as markers of subclinical atherosclerosis in pts with psoriatic arthritis (PA. Material and methods. 130 pts with PA (51 male and 79 female without clinical signs of coronary heart disease (CHD and stroke. were included. Mean age was 43 years (39-48 years, mean PA duration – 7 years (2 months-42 years, mean psoriasis duration – 15 years (5,5 – 26 years. PA activity was assessed with DAS4. Age, total cholesterol (TC, high density lipoprotein (HDLP, low density lipoprotein (LDLP, C-reactive protein (CRP, fibrinogen, systolic blood pressure, body mass index (BMI, atherogenity coefficient (AC, relative risk of CHD development, presence of diabetes and smoking were evaluated. Mean and maximal intima-media complex thickness (IMCT of common carotid arteries was examined with duplex scanning. Results. TC, LDLP and AC elevation was revealed in all and BMI elevation – in one third of pts. In 55% of pts CVR was mean and higher, in 23,5% CVR was absent and in 21,5% CVR was below mean. CVR significantly correlated with mean and maximal carotid arteries IMCT (R=0,48, p<0,00001 and R=0,41, p<0,00001 and fibrinogen (R=0,22, p<0,011. In women CVR correlated with fibrinogen (R=0,27, p<0,16, BMI (R=0,35, p<0,16, mean and maximal carotid arteries IMCT (R=0,50, p<0,00001 and R=0,38, p<0,0005 respectively and psoriasis duration (R=0,30, p<0,006. In men CVR did not correlated with fibrinogen. CVR did not correlated with DAS4 and CRP. Conclusion. CVR in PA is not connected with traditional markers of inflammation andindex of clinical disease activity.

  7. Role of vitamin K-dependent proteins in the arterial vessel wall.

    Science.gov (United States)

    Chatrou, M L L; Reutelingsperger, C P; Schurgers, L J

    2011-11-01

    Vitamin K was discovered early last century at the same time as the vitamin K-antagonists. For many years the role of vitamin K was solely ascribed to coagulation and coagulation was thought to be involved only at the venous blood side. This view has dramatically changed with the discovery of vitamin K-dependent proteins outside the coagulation cascade and the role of coagulation factors at the arterial side. Vitamin K-dependent proteins are involved in the regulation of vascular smooth muscle cell migration, apoptosis, and calcification. Vascular calcification has become an important independent predictor of cardiovascular disease. Vitamin K-antagonists induce inactivity of inhibitors of vascular calcification, leading to accelerated calcification. The involvement of vitamin K-dependent proteins such as MGP in vascular calcification make that calcification is amendable for intervention with high intake of vitamin K. This review focuses on the effect of vitamin K-dependent proteins in vascular disease.

  8. Diagnostic performance of colour duplex ultrasonography along with temporal artery biopsy in suspicion of giant cell arteritis.

    Science.gov (United States)

    Roncato, Christophe; Allix-Béguec, Caroline; Brottier-Mancini, Elisabeth; Gombert, Bruno; Denis, Guillaume

    2017-01-01

    Giant cell arteritis (GCA) is a vasculitis that occurs in older adults, affecting vessels of medium and large caliber. GCA diagnosis is a challenge for general practitioners and specialists. The aim of this study was to retrospectively analyse performances of temporal artery biopsy (TAB) and colour duplex ultrasonography (CDU) for GCA diagnosis. All patients with suspicion of GCA and who underwent both TAB and CDU between April 2009 and March 2014 were included in the study. A positive CDU examination was defined by halos on both superficial temporal arteries. Patients were classified based on the physician final diagnosis. Among the 42 eligible patients, 12 had an alternative diagnosis and 30 were diagnosed with GCA. Sensitivities were 77% and 80% for TAB and CDU examinations, respectively. Specificities were 100% for both tests. Twenty-nine (96.7%) patients with GCA had their diagnosis confirmed either by CDU and/or by TAB. Time lengths between the first medical examination and results of TAB and CDU were 15 and 4.2 days (p<0.001), respectively. Our study suggests that in suspected GCA, CDU may be used as first line examination followed by TAB in case of CDU negative results. Such algorithm needs to be further assessed in a multicentre prospective study.

  9. A model of smooth muscle cell synchronization in the arterial wall

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Aalkjær, Christian; Nilsson, Holger

    2007-01-01

    in membrane potential and flow of current through gap junctions. The amplitude of these oscillations in potential grows with increasing [cGMP], and, past a certain threshold, they become strong enough to entrain all cells in the vascular wall, thereby initiating sustained vasomotion. In this state...... number of cells. Gap-junctional current between cells is due to the appearance of oscillations in the membrane potential that again depends on the entrainment of sarcoplasmic reticulum and plasma membrane within the individual cell.......Vasomotion is a rhythmic variation in microvascular diameter. Although known for more than 150 years, the cellular processes underlying the initiation of vasomotion are not fully understood. In the present study a model of a single cell is extended by coupling a number of cells into a tube...

  10. Associations of Coronary Heart Disease with Common Carotid Artery Near and Far Wall Intima-Media Thickness: The Multi-Ethnic Study of Atherosclerosis.

    Science.gov (United States)

    Polak, Joseph F; Szklo, Moyses; O'Leary, Daniel H

    2015-09-01

    Intima-media thickness (IMT) measured on ultrasound images of the common carotid artery (CCA) is associated with cardiovascular risk factors and events. Given the physics of ultrasound, CCA far wall IMT measurements are favored over near wall measurements, but this theoretical advantage is not well studied. A total of 6,606 members of the Multi-Ethnic Study of Atherosclerosis, a longitudinal cohort study (mean age, 62.1 years; 52.7% women) who had near wall and far wall CCA IMT measurements. Multivariate linear regression models were used to estimate model goodness of fit of Framingham risk factors with near wall IMT, far wall IMT, and combined mean IMT. Multivariate Cox proportional hazards models were used to estimate hazard ratios for incident coronary heart disease events for each IMT variable. Change in Harrell's C statistic was used to compare the incremental value of each IMT variable when added to Framingham risk factors. Mean IMT had the strongest association with risk factors (R(2) = 0.31), followed by near wall (R(2) = 0.26) and far wall (R(2) = 0.22) IMT. Far wall IMT improved the prediction of coronary artery disease events over the Framingham risk factors (change in C statistic, 0.012; 95% CI, 0.006-0.017; P coronary heart disease, whereas mean IMT had the strongest associations with risk factors. This difference might affect the selection of appropriate IMT variables in different studies. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  11. Diagnosis of bronchiectasis and airway wall thickening in children with cystic fibrosis. Objective airway-artery quantification

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Wieying; Tiddens, Harm A.W.M. [Erasmus MC - Sophia Children' s Hospital, Department of Pediatric Pulmonology and Allergology, Rotterdam (Netherlands); Erasmus MC, Department of Radiology, Rotterdam (Netherlands); Bruijne, Marleen de [Erasmus MC, Biomedical Imaging Group Rotterdam, Departments of Medical Informatics and Radiology, Rotterdam (Netherlands); University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Petersen, Jens [University of Copenhagen, Department of Computer Science, Copenhagen (Denmark); Nasserinejad, Kazem [Erasmus MC Cancer Institute, HOVON Data Center, Clinical Trial Center, Rotterdam (Netherlands); Erasmus MC, Department of Biostatistics, Rotterdam (Netherlands); Ozturk, Hadiye [Erasmus MC - Sophia Children' s Hospital, Department of Pediatric Pulmonology and Allergology, Rotterdam (Netherlands); Chen, Yong [General Hospital of Ningxia Medical University, Department of Radiology, Yinchuan (China); Perez-Rovira, Adria [Erasmus MC - Sophia Children' s Hospital, Department of Pediatric Pulmonology and Allergology, Rotterdam (Netherlands); Erasmus MC, Biomedical Imaging Group Rotterdam, Departments of Medical Informatics and Radiology, Rotterdam (Netherlands)

    2017-11-15

    To quantify airway and artery (AA)-dimensions in cystic fibrosis (CF) and control patients for objective CT diagnosis of bronchiectasis and airway wall thickness (AWT). Spirometer-guided inspiratory and expiratory CTs of 11 CF and 12 control patients were collected retrospectively. Airway pathways were annotated semi-automatically to reconstruct three-dimensional bronchial trees. All visible AA-pairs were measured perpendicular to the airway axis. Inner, outer and AWT (outer-inner) diameter were divided by the adjacent artery diameter to compute A{sub in}A-, A{sub out}A- and A{sub WT}A-ratios. AA-ratios were predicted using mixed-effects models including disease status, lung volume, gender, height and age as covariates. Demographics did not differ significantly between cohorts. Mean AA-pairs CF: 299 inspiratory; 82 expiratory. Controls: 131 inspiratory; 58 expiratory. All ratios were significantly larger in inspiratory compared to expiratory CTs for both groups (p<0.001). A{sub out}A- and A{sub WT}A-ratios were larger in CF than in controls, independent of lung volume (p<0.01). Difference of A{sub out}A- and A{sub WT}A-ratios between patients with CF and controls increased significantly for every following airway generation (p<0.001). Diagnosis of bronchiectasis is highly dependent on lung volume and more reliably diagnosed using outer airway diameter. Difference in bronchiectasis and AWT severity between the two cohorts increased with each airway generation. (orig.)

  12. Statistical Permutation-based Artery Mapping (SPAM): a novel approach to evaluate imaging signals in the vessel wall.

    Science.gov (United States)

    Seifert, Robert; Scherzinger, Aaron; Kiefer, Friedemann; Hermann, Sven; Jiang, Xiaoyi; Schäfers, Michael A

    2017-05-26

    Cardiovascular diseases are the leading cause of death worldwide. A prominent cause of cardiovascular events is atherosclerosis, a chronic inflammation of the arterial wall that leads to the formation of so called atherosclerotic plaques. There is a strong clinical need to develop new, non-invasive vascular imaging techniques in order to identify high-risk plaques, which might escape detection using conventional methods based on the assessment of the luminal narrowing. In this context, molecular imaging strategies based on fluorescent tracers and fluorescence reflectance imaging (FRI) seem well suited to assess molecular and cellular activity. However, such an analysis demands a precise and standardized analysis method, which is orientated on reproducible anatomical landmarks, ensuring to compare equivalent regions across different subjects. We propose a novel method, Statistical Permutation-based Artery Mapping (SPAM). Our approach is especially useful for the understanding of complex and heterogeneous regional processes during the course of atherosclerosis. Our method involves three steps, which are (I) standardisation with an additional intensity normalization, (II) permutation testing, and (III) cluster-enhancement. Although permutation testing and cluster enhancement are already well-established in functional magnetic resonance imaging, to the best of our knowledge these strategies have so far not been applied in cardiovascular molecular imaging. We tested our method using FRI images of murine aortic vessels in order to find recurring patterns in atherosclerotic plaques across multiple subjects. We demonstrate that our pixel-wise and cluster-enhanced testing approach is feasible and useful to analyse tracer distributions in FRI data sets of aortic vessels. We expect our method to be a useful tool within the field of molecular imaging of atherosclerotic plaques since cluster-enhanced permutation testing is a powerful approach for finding significant differences

  13. The subpetrous carotid wall hematoma. A sign of spontaneous dissection of the internal carotid artery on non-enhanced computed tomography. A retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Jensen-Kondering, U. [Univ. Hospital Schleswig-Holstein, Kiel (Germany). Dept. of Radiology and Neuroradiology; Univ. Hospital Schleswig-Holstein, Kiel (Germany). Dept. of Neurology; Huhndorf, M.; Madjidyar, J.; Jansen, O. [Univ. Hospital Schleswig-Holstein, Kiel (Germany). Dept. of Radiology and Neuroradiology

    2015-03-15

    Spontaneous dissection of the internal carotid artery (CAD) is an increasingly recognized cause for stroke especially in young and middle-aged patients. We hypothesized that non-enhanced cranial computed tomography (NECCT) can visualize the subpetrous carotid wall hematoma and thus enable identification of patients with CAD. We retrospectively reviewed patients with confirmed CAD (n=21) and a control group with ischemic symptoms but without CAD (n=42) who received NECCT at admission. Two independent neuroradiologists rated the presence and shape of SPH, density and diameter of the subpetrous internal carotid artery. Additionally, we correlated the shape of the subpetrous carotid wall hematoma with the grade of stenosis on subsequent angiographic imaging. The subpetrous carotid wall hematoma was present in 14 of 21 patients (Cohen's k = 0.67). Mean diameter was 6.95 ± 1.05 mm in dissected vessels and 5.71 ± 1.52 mm in the contralateral vessel (p<0.05). Mean difference in vessel density was 15.05 ± 8.01 HU (p<0.01). Median grade of stenosis was significantly higher in patients with a full moon- shaped (n=11) than crescent-shaped (n=3) subpetrous carotid wall hematoma (21% vs. 80%, p<0.05). Two-thirds of patients with CAD were correctly identified on NECCT. The extracranial carotid artery should be evaluated in patients with symptoms of cerebral ischemia.

  14. Clinical anatomy of the inferior epigastric artery with special relevance to invasive procedures of the anterior abdominal wall

    Directory of Open Access Journals (Sweden)

    Praisy Joy

    2017-01-01

    Full Text Available Introduction: Injury to the inferior epigastric artery (IEA has been reported following lower abdominal wall surgical incisions, abdominal peritoneocentesis and trocar placements at laparoscopic port sites, resulting in the formation of abdominal wall haematomas that may expand considerably due to lack of tissue resistance. The aim of this study was to localise its course in relation to standard anatomic landmarks and suggest safe areas for performance of invasive procedures. Materials and Methods: Sixty IEAs of 30 adult cadavers (male = 19; female = 11 were dissected and the course of the IEA noted in relation to the mid-inguinal point, anterior superior iliac spine (ASIS and umbilicus. Results: The mean distance of the IEA from the midline was 4.45 ± 1.42 cm at the level of the mid-inguinal point, 4.10 ± 1.15 cm at the level of ASIS and 4.49 ± 1.15 cm at the level of umbilicus. There was an average of 3.3 branches per IEA with more branches arising from its lateral aspect. The IEA was situated within one-third (32% of the distance between the midline and the sagittal plane through ASIS at all levels. Conclusion: To avoid injury to IEA, trocars can be safely inserted 5.5 cm [mean + 1 standard deviation (SD] away from the midline (or slightly more than one-third of the distance between the midline and a sagittal plane running through ASIS. These findings may be useful not only for laparoscopic procedures but also for image-guided biopsy, abdominal paracentesis, and placement of abdominal drains.

  15. Evaluation of statin therapy on endothelial function in hypercholesterolemic rabbits by automatic measurement of arterial wall movement using ultrasound images.

    Science.gov (United States)

    Rahmani-Cherati, Tavoos; Mokhtari-Dizaji, Manijhe; Vajhi, Alireza; Rostami, Abdorrazzagh

    2014-10-01

    The aim of this study was to evaluate arterial endothelial function, assessed as acetylcholine-mediated dilation (AMD), in a hypercholesterolemic atherosclerotic rabbit model to investigate the effects of atorvastatin in the atherosclerotic process, using a new computerized analysis model and ultrasound images. Twenty-seven rabbits were fed a high-cholesterol (2%) diet for 6 wk and then divided into three groups for an additional 9 wk: Group A received regular chow food, group B received a 2% cholesterol-rich diet plus atorvastatin drug, and group C received regular chow food plus atorvastatin. Ultrasound examinations of endothelial function of the rabbit abdominal aorta artery were performed immediately after the 6 weeks (0 wk) and then 3, 6 and 9 wk after that. For off-line analysis, a computerized analysis method for evaluating instantaneous changes in the wall of the rabbit abdominal aorta was used. As parameters of improvement resulting from treatment, endothelium-dependent acetylcholine-induced dilation and endothelium-independent nitroglycerin-induced dilation were evaluated in treated rabbits. Differences among groups were tested using analysis of variance. On histopathology, intima-media thickness decreased after treatment in all groups. There were no significant differences in arterial diameter and blood velocity changes among treated rabbits at 0, 3, 6 and 9 wk of treatment in all groups, except in end-diastolic velocity, radial strain percentage, pulse index and resistance index in group C. In group A, AMD did not significantly improve after 3, 6 and 9 wk, as compared with 0 wk. Atorvastatin treatment significantly increased AMD (18%) at 3 wk in group B, compared with week 0. AMD significantly increased after 3 (26%), 6 (124%) and 9 (182%) wk in group C, compared with 0 wk. It is concluded that the new automatic method enables accurate and repeated evaluation of endothelial function during the progression and regression of atherosclerosis. Also, the

  16. Structural alterations of the coronary arterial wall are associated with myocardial flow heterogeneity in type 2 diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Thomas H. [California Univ., Los Angeles, CA (United States). Dept. of Moelecular and Medical Pharmacology, Radiological Science]|[University Hospital of Geneva, Department of Internal Medicine, Cardiovascular Center, Nuclear Cardiology, Geneva (Switzerland); Facta, Alvaro D.; Prior, John O.; Cadenas, Jerson; Zhang, Xiao-Li; Sayre, James; Goldin, Jonathan; Schelbert, Heinrich R. [California Univ., Los Angeles, CA (United States). Dept. of Moelecular and Medical Pharmacology, Radiological Science; Li, Yanjie [University of Southern California, Atherosclerosis Research Unit, Keck School of Medicine, Los Angeles, CA (United States)

    2009-02-15

    To determine the relationship between carotid intima-media thickness (IMT), coronary artery calcification (CAC), and myocardial blood flow (MBF) at rest and during vasomotor stress in type 2 diabetes mellitus (DM). In 68 individuals, carotid IMT was measured using high-resolution vascular ultrasound, while the presence of CAC was determined with electron beam tomography (EBT). Global and regional MBF was determined in milliliters per gram per minute with {sup 13}N-ammonia and positron emission tomography (PET) at rest, during cold pressor testing (CPT), and during adenosine (ADO) stimulation. There was neither a relationship between carotid IMT and CAC (r = 0.10, p = 0.32) nor between carotid IMT and coronary circulatory function in response to CPT and during ADO (r = -0.18, p = 0.25 and r = 0.10, p = 0.54, respectively). In 33 individuals, EBT detected CAC with a mean Agatston-derived calcium score of 44 {+-} 18. There was a significant difference in regional MBFs between territories with and without CAC at rest and during ADO-stimulated hyperemia (0.69 {+-} 0.24 vs. 0.74 {+-} 0.23 and 1.82 {+-} 0.50 vs. 1.95 {+-} 0.51 ml/g/min; p {<=} 0.05, respectively) and also during CPT in DM but less pronounced (0.81 {+-} 0.24 vs. 0.83 {+-} 0.23 ml/g/min; p = ns). The increase in CAC was paralleled with a progressive regional decrease in resting as well as in CPT- and ADO-related MBFs (r = -0.36, p {<=} 0.014; r = -0.46, p {<=} 0.007; and r = -0.33, p {<=} 0.041, respectively). The absence of any correlation between carotid IMT and coronary circulatory function in type 2 DM suggests different features and stages of early atherosclerosis in the peripheral and coronary circulation. PET-measured MBF heterogeneity at rest and during vasomotor stress may reflect downstream fluid dynamic effects of coronary artery disease (CAD)-related early structural alterations of the arterial wall. (orig.)

  17. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry.

    Directory of Open Access Journals (Sweden)

    Kweon-Ho Nam

    Full Text Available Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with

  18. Assessment of Hyperperfusion by Brain Perfusion SPECT in Transient Neurological Deterioration after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis Surgery

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Won; Kim, Yu Kyeong; Lee, Sang Mi; Eo, Jae Sun; Oh, Chang Wan; Lee, Won Woo; Paeng, Jin Chul; Kim, Sang Eun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2008-08-15

    Transient neurological deterioration (TND) is one of the complications after extracranial-intracranial bypass surgery, and it has been assumed to be caused by postoperative transient hyperperfusion. This study was performed to evaluate the relationship between TND and preoperative and postoperative cerebral perfusion status on brain perfusion SPECT following superficial temporal artery.middle cerebral artery (STA-MCA) anastomosis surgery. A total of 60 STA-MCA anastomosis surgeries of 56 patients (mean age: 50{+-}16 yrs; M:F=29:27; atherosclerotic disease: 33, moyamoya disease: 27) which were done between September 2003 and July 2006 were enrolled. The resting cerebral perfusion and cerebral vascular reserve (CVR) after acetazolamide challenge were measured before and 10 days after surgery using 99mTc-ethylcysteinate dimer (ECD) SPECT. Moreover, the cerebral perfusion was measured on the third postoperative day. With the use of the statistical parametric mapping and probabilistic brain atlas, the counts for the middle cerebral artery (MCA) territory were calculated for each image, and statistical analyses were performed. In 6 of 60 cases (10%), TND occurred after surgery. In all patients, the preoperative cerebral perfusion of affected MCA territory was significantly lower than that of contralateral side (p=0.002). The cerebral perfusion on the third and tenth day after surgery was significantly higher than preoperative cerebral perfusion (p=0.001, p=0.02). In TND patients, basal cerebral perfusion and CVR on preoperative SPECT were significantly lower than those of non-TND patients (p=0.01, p=0.05). Further, the increases in cerebral perfusion on the third day after surgery were significant higher than those in other patients (p=0.008). In patients with TND, the cerebral perfusion ratio of affected side to contralateral side on third postoperative day was significantly higher than that of other patients (p=0.002). However, there was no significant difference of

  19. Superficial temporal artery: the "C" shape half-buttonhole configuration as it courses over the zygomatic arch.

    Science.gov (United States)

    Cobb, Mary In-Ping Huang; Galvin, Leo; Gonzalez, L Fernando

    2016-05-01

    To describe the course and configuration of the superficial temporal artery (STA) around the zygomatic arch. Volume rendered 3D reconstructions of computed tomography angiography of 25 healthy patients were performed and analyzed at Duke University Hospitals. The STA coursed over the zygomatic arch or over the condylar process of the mandible in all cases (25/25 pts, 100 %). The STA courses over the posterior zygomatic arch in 23/25 pts (92 %), creating a characteristic "C" shape half-buttonhole configuration as it embraces the arch. When the STA travels posterior to the zygomatic arch, there is no C shape configuration (2/25 pts, 8 %). The STA bifurcates distal to the zygomatic arch in 24/25 pts (96 %). The "C" shape half-buttonhole configuration is a useful identifying characteristic of the most common course of the STA-over the posterior zygomatic arch before it bifurcates.

  20. Temporal and spatial dynamics of optical emission from laser ablation of the first wall materials of fusion device

    Science.gov (United States)

    Dongye, ZHAO; Cong, LI; Yong, WANG; Zhiwei, WANG; Liang, GAO; Zhenhua, HU; Jing, WU; Guang-Nan, LUO; Hongbin, DING

    2018-01-01

    Laser-induced breakdown spectroscopy (LIBS) has been developed to in situ diagnose the chemical compositions of the first wall in the EAST tokamak. However, the dynamics of optical emission of the key plasma-facing materials, such as tungsten, molybdenum and graphite have not been investigated in a laser produced plasma (LPP) under vacuum. In this work, the temporal and spatial dynamics of optical emission were investigated using the spectrometer with ICCD. Plasma was produced by an Nd:YAG laser (1064 nm) with pulse duration of 6 ns. The results showed that the typical lifetime of LPP is less than 1.4 μs, and the lifetime of ions is shorter than atoms at ∼10‑6 mbar. Temporal features of optical emission showed that the optimized delay times for collecting spectra are from 100 to 400 ns which depended on the corresponding species. For spatial distribution, the maximum LIBS spectral intensity in plasma plume is obtained in the region from 1.5 to 3.0 mm above the sample surface. Moreover, the plasma expansion velocity involving the different species in a multicomponent system was measured for obtaining the proper timing (gate delay time and gate width) of the maximum emission intensity and for understanding the plasma expansion mechanism. The order of expansion velocities for various species is {V}{{{C}}+}> {V}{{H}}> {V}{{{Si}}+}> {V}{{Li}}> {V}{{Mo}}> {V}{{W}}. These results could be attributed to the plasma sheath acceleration and mass effect. In addition, an optimum signal-to-background ratio was investigated by varying both delay time and detecting position.

  1. Coating the wall of an injured intracranial carotid artery during tumor removal with n-butyl-2-cyanoacrylate: technical case report.

    Science.gov (United States)

    Requejo, Flavio; Schumacher, Martin; van Velthoven, Vera

    2006-10-01

    Carotid artery injury close to the clinoid process is difficult to repair, and is even more so when the vessel is firmly attached to a calcified tumor. We treated a patient with an intraoperative carotid lesion by coating the vessel wall with n-butyl-2-cyanoacrylate (NBCA). A 7-year-old boy was referred to our clinic with a 3-month history of somnolence, apathy, and headache. Neurological examination revealed bitemporal hemianopsia. The cranial magnetic resonance imaging and computed tomographic scans showed a sellar and suprasellar calcified mass with heterogeneous contrast enhancement, a cyst component in the upper part of the tumor displaced upward and back from the mesencephalic and diencephalic structures. The patient underwent a pterional craniotomy. Using a microsurgical technique, the suprasellar part of the craniopharyngioma was removed. In an attempt to dissect the calcified mass from the carotid artery on the right side, the vessel was unintentionally injured, followed by severe bleeding. Temporary occlusion and suturing of the vessel was impossible because of the overlying hard mass. To avoid a permanent occlusion, we decided to coat the injured artery wall with 100% NBCA. For this, 0.5 ml of NBCA was distributed on the surface of the injured segment and surrounding subarachnoid space by injection through a needle. An excellent hemostasis could be obtained immediately after coating. The patient woke up with no new neurological deficits. A digital cerebral angiogram obtained a few days after the procedure did not show vasospasm, stenosis, or pseudoaneurysm in the supraclinoidal segment of the carotid artery. A magnetic resonance angiogram obtained 3 years later showed a normal shape of the internal carotid artery and a stable residual tumor without inflammatory signs. The child is now attending school and is under hormonal therapy. For hemostatic purposes, the technique of coating an injured arterial wall with NBCA may be useful in cases in which a

  2. Threshold Setting for Likelihood Function for Elasticity-Based Tissue Classification of Arterial Walls by Evaluating Variance in Measurement of Radial Strain

    Science.gov (United States)

    Tsuzuki, Kentaro; Hasegawa, Hideyuki; Kanai, Hiroshi; Ichiki, Masataka; Tezuka, Fumiaki

    2008-05-01

    Pathologic changes in arterial walls significantly influence their mechanical properties. We have developed a correlation-based method, the phased tracking method [H. Kanai et al.: IEEE Trans. Ultrason. Ferroelectr. Freq. Control 43 (1996) 791], for measurement of the regional elasticity of the arterial wall. Using this method, elasticity distributions of lipids, blood clots, fibrous tissue, and calcified tissue were measured in vitro by experiments on excised arteries (mean±SD: lipids 89±47 kPa, blood clots 131 ±56 kPa, fibrous tissue 1022±1040 kPa, calcified tissue 2267 ±1228 kPa) [H. Kanai et al.: Circulation 107 (2003) 3018; J. Inagaki et al.: Jpn. J. Appl. Phys. 44 (2005) 4593]. It was found that arterial tissues can be classified into soft tissues (lipids and blood clots) and hard tissues (fibrous tissue and calcified tissue) on the basis of their elasticity. However, there are large overlaps between elasticity distributions of lipids and blood clots and those of fibrous tissue and calcified tissue. Thus, it was difficult to differentiate lipids from blood clots and fibrous tissue from calcified tissue by simply thresholding elasticity value. Therefore, we previously proposed a method by classifying the elasticity distribution in each region of interest (ROI) (not a single pixel) in an elasticity image into lipids, blood clots, fibrous tissue, or calcified tissue based on a likelihood function for each tissue [J. Inagaki et al.: Jpn. J. Appl. Phys. 44 (2006) 4732]. In our previous study, the optimum size of an ROI was determined to be 1,500 µm in the arterial radial direction and 1,500 µm in the arterial longitudinal direction [K. Tsuzuki et al.: Ultrasound Med. Biol. 34 (2008) 573]. In this study, the threshold for the likelihood function used in the tissue classification was set by evaluating the variance in the ultrasonic measurement of radial strain. The recognition rate was improved from 50 to 54% by the proposed thresholding.

  3. Is bronchial wall imaging affected by temporal resolution? Comparative evaluation at 140 and 75 ms in 90 patients

    Energy Technology Data Exchange (ETDEWEB)

    Hutt, Antoine; Tacelli, Nunzia; Faivre, Jean-Baptiste; Remy, Jacques; Remy-Jardin, Martine [CHRU et Universite de Lille, Department of Thoracic Imaging, Hospital Calmette (EA 2694), Lille (France); Flohr, Thomas [Computed Tomography, Siemens Healthcare, Forchheim (Germany); Duhamel, Alain [CHRU et Universite de Lille, Department of Biostatistics (EA 2694), Lille (France)

    2016-02-15

    To evaluate the influence of temporal resolution (TR) on cardiogenic artefacts at the level of bronchial walls. Ninety patients underwent a dual-source, single-energy chest CT examination enabling reconstruction of images with a TR of 75 ms (i.e., optimized TR) (Group 1) and 140 ms (i.e., standard TR) (Group 2). Cardiogenic artefacts were analyzed at the level of eight target bronchi, i.e., right (R) and left (L) B1, B5, B7, and B10 (total number of bronchi examined: n = 720). Cardiogenic artefacts were significantly less frequent and less severe in Group 1 than in Group 2 (p < 0.0001) with the highest scores of discordant ratings for bronchi in close contact with cardiac cavities: RB5 (61/90; 68 %); LB5 (66/90; 73 %); LB7 (63/90; 70 %). In Group 1, 78 % (560/720) of bronchi showed no cardiac motion artefacts, whereas 22 % of bronchi (160/720) showed artefacts rated as mild (152/160; 95 %), moderate (7/160; 4 %), and severe (1/160; 1 %). In Group 2, 70 % of bronchi (503/720) showed artefacts rated as mild (410/503; 82 %), moderate (82/503; 16 %), and severe (11/503; 2 %). At 75 ms, most bronchi can be depicted without cardiogenic artefacts. (orig.)

  4. Fluid-structure interaction analysis on the effect of vessel wall hypertrophy and stiffness on the blood flow in carotid artery bifurcation

    Science.gov (United States)

    Lee, Sang Hoon; Choi, Hyoung Gwon; Yoo, Jung Yul

    2012-11-01

    The effect of artery wall hypertrophy and stiffness on the flow field is investigated using three-dimensional finite element method for simulating the blood flow. To avoid the complexity due to the necessity of additional mechanical constraints, we use the combined formulation which includes both the fluid and structural equations of motion into single coupled variational equation. A P2P1 Galerkin finite element method is used to solve the Navier-Stokes equations for fluid flow and arbitrary Lagrangian-Eulerian formulation is used to achieve mesh movement. The Newmark method is employed for solving the dynamic equilibrium equations for linear elastic solid mechanics. The pulsatile, incompressible flows of Newtonian fluids constrained in the flexible wall are analyzed with Womersley velocity profile at the inlet and constant pressure at the outlet. The study shows that the stiffness of carotid artery wall affects significantly the flow phenomena during the pulse cycle. Similarly, it is found that the flow field is also strongly influenced by wall hypertrophy. This work was supported by Mid-career Researcher Program and Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0079936 & 2011-0029613).

  5. Differentiation of deep subcortical infarction using high-resolution vessel wall MR imaging of middle cerebral artery

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yun Jung; Choi, Byung Se; Jung, Cheol Kyu; Yoon, Yeon Hong; Sunwoo, Leonard; Kim, Jae Hyoung; Bae, Hee Joon [Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2017-11-15

    To evaluate the utility of high-resolution vessel wall imaging (HR-VWI) of middle cerebral artery (MCA), and to compare HR-VWI findings between striatocapsular infarction (SC-I) and lenticulostriate infarction (LS-I). This retrospective study was approved by the Institutional Review Board, and informed consent was waived. From July 2009 to February 2012, 145 consecutive patients with deep subcortical infarctions (SC-I, n = 81; LS-I, n = 64) who underwent HR-VWI were included in this study. The degree of MCA stenosis and the characteristics of MCA plaque (presence, eccentricity, location, extent, T2-high signal intensity [T2-HSI], and plaque enhancement) were analyzed, and compared between SC-I and LS-I, using Fisher's exact test. Stenosis was more severe in SC-I than in LS-I (p = 0.040). MCA plaque was more frequent in SC-I than in LS-I (p = 0.028), having larger plaque extent (p = 0.001), more T2-HSI (p = 0.001), and more plaque enhancement (p = 0.002). The eccentricity and location of the plaque showed no significant difference between the two groups.Both SC-I and LS-I have similar HR-VWI findings of the MCA plaque, but SC-I had more frequent, larger plaques with greater T2-HSI and enhancement. This suggests that HR-VWI may have a promising role in assisting the differentiation of underlying pathophysiological mechanism between SC-I and LS-I.

  6. A pilot trial to examine the effect of high-dose niacin on arterial wall inflammation using fluorodeoxyglucose positron emission tomography.

    Science.gov (United States)

    deGoma, Emil M; Salavati, Ali; Shinohara, Russell T; Saboury, Babak; Pollan, Laura; Schoen, Marisa; Torigian, Drew A; Mohler, Emile R; Dunbar, Richard L; Litt, Harold I; Woo, John; Rader, Daniel J; Alavi, Abass; Mehta, Nehal N

    2015-05-01

    Although studies have reported direct inhibition of inflammatory pathways with niacin, the effect of niacin on arterial wall inflammation remains unknown. We examined the effect of niacin on arterial (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT). Nine statin-treated patients with coronary disease were randomized to niacin 6000 mg/day or placebo. FDG-PET/CT and lipids were assessed at baseline and at 12 weeks. FDG was quantified in the aorta, right carotid artery, and left carotid artery as the target-to-background ratio (TBR) and target-to-background difference (TBD). Eight patients completed the study. No significant changes in FDG measured by aortic, left carotid, or right carotid TBR or TBD were seen in either group. Compared to baseline, niacin-treated subjects exhibited a significant 29% reduction in low-density lipoprotein cholesterol (LDL-C; 95% confidence interval [CI], -50% to 8%; P = .01) and a nonsignificant 29% reduction in LDL particle number (LDL-P; 95% CI, -58% to 0.2%; P = .07). A nonsignificant 11% increase in HDL-C (95% CI, -15% to 37%; P = .30) and 8% decrease in HDL-P (95% CI, -44% to 28%; P = .51) were observed with niacin treatment. In a pooled analysis, changes in LDL-P were positively correlated with FDG uptake in the aorta (TBR r = 0.66, P = .08; TBD r = 0.75, P = .03), left carotid (TBR r = 0.65, P = .08; TBD r = 0.74, P = .03), and right carotid (TBR r = 0.54, P = .17; TBD r = 0.61, P = .11). In this pilot study, adding niacin to statin therapy did not affect arterial wall inflammation measured by FDG-PET/CT. However, an association between changes in arterial FDG uptake and LDL-P was observed. Larger studies are needed to definitively examine the effect of niacin on arterial wall inflammation. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  7. Association of subclinical wall changes of carotid, femoral, and popliteal arteries with obstructive coronary artery disease in patients undergoing coronary angiography.

    Science.gov (United States)

    Kafetzakis, Alexandros; Kochiadakis, George; Laliotis, Aggelos; Peteinarakis, Ioannis; Touloupakis, Emmanouel; Igoumenidis, Nikos; Katsamouris, Asterios

    2005-10-01

    To examine the association of occult atherosclerosis of carotid, femoral, and popliteal arteries with the presence and severity of obstructive coronary artery disease (CAD) in patients without a history or presence of cerebrovascular or peripheral arterial disease using ultrasound examination of peripheral arteries. One hundred eighty-four such individuals underwent routine coronary angiography. Obstructive CAD was found in 103 cases, which comprised the patient group. The remaining 81 individuals comprised the control group. All were blindly examined by duplex ultrasonography in order to assess occult atherosclerosis, as indicated by the estimation of intima-media thickness of the carotid artery (IMTC), intima-media thickness of the femoral artery (IMTF), intima-media thickness of the popliteal artery (IMTP), and ultrasonic biopsy (UB) of the carotid and femoral arteries. For the individuals with positive coronary angiography findings, the severity of CAD was estimated by the number of the diseased vessels. IMTC, IMTF, IMTP, and UB showed significant correlation with the presence of obstructive CAD, but only IMTC and IMTF were independent predictive factors, with specificity of 74% and 60% and sensitivity of 76% and 70%, respectively. Additionally, our analysis yielded a regression model that, for a given value of IMTC and IMTF, may estimate the probability of CAD: p (CAD) = e((- 4.765 + 3.36 IMTC + 1.91 IMTF))/1 + e((- 4.765 + 13.36 IMTC + 1.91 IMTF)). Patients with one-vessel disease had significantly lower IMTC (p disease. The assessment of occult atherosclerosis by duplex ultrasonography in both the carotid and the femoral arteries is significantly associated with the presence and severity of CAD.

  8. Understanding Arteries | Coronary Artery Disease | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... Artery If plaque continues to build up, the space inside the artery narrows. The artery walls become ... Plaque forms within the artery walls, narrowing the space inside and sometimes blocking blood flow. This process ...

  9. Central aortic blood pressure from ultrasound wall-tracking of the carotid artery in children: comparison with invasive measurements and radial tonometry.

    Science.gov (United States)

    Milne, Laura; Keehn, Louise; Guilcher, Antoine; Reidy, John F; Karunanithy, Narayan; Rosenthal, Eric; Qureshi, Shakeel; Chowienczyk, Phil J; Sinha, Manish D

    2015-05-01

    Differences between central aortic root (c) and peripheral (p) systolic blood pressure (SBP) may be particularly marked in children, but noninvasive methods for assessing cSBP in children have not been validated. We compared estimates of cSBP obtained from radiofrequency ultrasound wall tracking of the carotid artery (ART.LAB system) with that measured directly by a catheter in the aortic root at the time of arterial cannulation. Carotid waveforms were calibrated from invasive measurements of mean and diastolic pressures. In 9 children aged 10.5 ± 5.0 years (mean ± SD), cSBP obtained from carotid wall tracking was highly correlated with invasive measures of cSBP (r=0.99) with mean (± SD) difference 3.9 ± 2.5 mm Hg. Second, we compared values of cSBP obtained from the carotid with those obtained using noninvasive applanation tonometry at the radial artery and a radial-to-aortic transfer function (SphygmoCor). Both carotid and radial tonometric measurements were calibrated from the same peripheral mean and diastolic measurements of blood pressure obtained by sphygmomanometry. In 84 children aged 13.2 ± 3.2 years, there was excellent agreement between the 2 methods (r=0.95; Pinvasive validation study confirms that cSBP as estimated by carotid wall tracking provides an acceptable measurement of true cSBP when calibration is from true mean and diastolic pressures. Close agreement of cSBP obtained by carotid wall tracking and radial tonometry suggests that these provide similar results when calibrated from the same peripheral blood pressure measurements. © 2015 American Heart Association, Inc.

  10. Postoperative Dilatation of Superficial Temporal Artery Associated with Transient Neurologic Symptoms After Direct Bypass Surgery for Moyamoya Angiopathy.

    Science.gov (United States)

    Ishii, Daizo; Okazaki, Takahito; Matsushige, Toshinori; Shinagawa, Katsuhiro; Ichinose, Nobuhiko; Sakamoto, Shigeyuki; Kurisu, Kaoru

    2017-10-01

    In moyamoya angiopathy, transient neurologic symptoms (TNS) are occasionally observed after superficial temporal artery (STA)-middle cerebral artery direct bypass surgery. The purpose of this study was to investigate the correlation between TNS and postoperative magnetic resonance imaging as well as perform a perfusion study. We reviewed 52 hemispheres in 33 consecutive patients with moyamoya angiopathy. TNS were defined as reversible neurologic dysfunction without any apparent intracranial infarction or hemorrhage. All patients underwent magnetic resonance imaging and single-photon emission computed tomography before and within 5 days after surgery. Maximum diameter of STA on time-of-flight magnetic resonance angiography and the dilatation ratio of STA were calculated. The presence of signal changes on fluid-attenuated inversion recovery images and regional cerebral blood flow were also evaluated. TNS were observed in 13 of 52 (25%) cases 1-16 days after surgery. The mean preoperative STA dilatation, postoperative STA dilatation, and dilatation ratio of STA were 1.33 mm ± 0.27, 1.67 mm ± 0.30, and 29.31% ± 28.13%. Postoperative intraparenchymal cortical hyperintensity lesions and high-intensity signals in the cortex sulci (ivy sign) were detected in 24 (46.2%) cases and 29 (55.8%) cases, respectively. Univariate analyses demonstrated no association between TNS and postoperative signal change on fluid-attenuated inversion recovery images as well as cerebral blood flow. Only >1.5-fold dilatation of STA was significantly correlated with TNS (P dilatation was correlated with TNS after direct bypass surgery for moyamoya angiopathy. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Optimal temporal windows and dose-reducing strategy for coronary artery bypass graft imaging with 256-slice CT

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Kun-Mu [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, 95 Wen Chang Road, Shih Lin District, Taipei 111, Taiwan. (China); Lee, Yi-Wei [Department of Radiology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan (China); Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taipei, Taiwan (China); Guan, Yu-Xiang [Department of Biomedical Imaging and Radiological Sciences, National Yang Ming University, Taipei, Taiwan (China); Chen, Liang-Kuang [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, 95 Wen Chang Road, Shih Lin District, Taipei 111, Taiwan. (China); School of Medicine, Fu Jen Catholic University, Taipei, Taiwan (China); Law, Wei-Yip, E-mail: m002325@ms.skh.org.tw [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, 95 Wen Chang Road, Shih Lin District, Taipei 111, Taiwan. (China); Su, Chen-Tau, E-mail: m005531@ms.skh.org.tw [Department of Radiology, Shin Kong Wu Ho-Su Memorial Hospital, 95 Wen Chang Road, Shih Lin District, Taipei 111, Taiwan. (China); School of Medicine, Fu Jen Catholic University, Taipei, Taiwan (China)

    2013-12-11

    Objective: To determine the optimal image reconstruction windows in the assessment of coronary artery bypass grafts (CABGs) with 256-slice computed tomography (CT), and to assess their associated optimal pulsing windows for electrocardiogram-triggered tube current modulation (ETCM). Methods: We recruited 18 patients (three female; mean age 68.9 years) having mean heart rate (HR) of 66.3 beats per minute (bpm) and a heart rate variability of 1.3 bpm for this study. A total of 36 CABGs with 168 segments were evaluated, including 12 internal mammary artery (33.3%) and 24 saphenous vein grafts (66.7%). We reconstructed 20 data sets in 5%-step through 0–95% of the R–R interval. The image quality of CABGs was assessed by a 5-point scale (1=excellent to 5=non-diagnostic) for each segment (proximal anastomosis, proximal, middle, distal course of graft body, and distal anastomosis). Two reviewers discriminated optimal reconstruction intervals for each CABG segment in each temporal window. Optimal windows for ETCM were also evaluated. Results: The determined optimal systolic and diastolic reconstruction intervals could be divided into 2 groups with threshold HR=68. The determined best reconstruction intervals for low heart rate (HR<68) and high heart rate (HR>68) were 76.0±2.5% and 45.0±0% respectively. Average image quality scores were 1.7±0.6 with good inter-observer agreement (Kappa=0.79). Image quality was significantly better for saphenous vein grafts versus arterial grafts (P<0.001). The recommended windows of ETCM for low HR, high HR and all HR groups were 40–50%, 71–81% and 40–96% of R-R interval, respectively. The corresponding dose savings were about 60.8%, 58.7% and 22.7% in that order. Conclusions: We determined optimal reconstruction intervals and ETCM windows representing a good compromise between radiation and image quality for following bypass surgery using a 256-slice CT.

  12. Validation of FDG uptake in the arterial wall as an imaging biomarker of atherosclerotic plaques with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT).

    Science.gov (United States)

    Bucci, Monica; Aparici, Carina Mari; Hawkins, Randy; Bacharach, Steve; Schrek, Carole; Cheng, Suchun; Tong, Elizabeth; Arora, Sandeep; Parati, Eugenio; Wintermark, Max

    2014-01-01

    From the literature, the prevalence of fluorodeoxyglucose (FDG) uptake in large artery atherosclerotic plaques shows great heterogeneity. We retrospectively reviewed 100 consecutive patients who underwent FDG-positron emission tomography-computed tomography (PET/CT) imaging of their whole body, to evaluate FDG uptake in the arterial wall. We retrospectively evaluated 100 whole-body PET-CT scans. The PET images coregistered with CT were reviewed for abnormal 18F-FDG uptake. The mean standard uptake value (SUV) was measured in regions of interest (ROIs). The prevalence of PET+ plaques was determined based on the qualitative PET review, used as the gold standard in a receiver-operating characteristic (ROC) curve analysis to determine an optimal threshold for the quantitative PET analysis. The qualitative, visual assessment demonstrated FDG uptake in the arterial walls of 26 patients. A total of 85 slices exhibited FDG uptake within the arterial wall of 37 artery locations. 11, 17, and 2 patients exhibited FDG uptake within the wall of carotid arteries, of the aorta, and of the iliac arteries, respectively. Only 4 of the 26 patients had positive FDG uptake in more than one artery location. In terms of quantitative analysis, a threshold of 2.8 SUV was associated with a negative predictive value of 99.4% and a positive predictive value of 100% to predict qualitative PET+ plaques. A threshold of 1.8 SUV was associated with a negative predictive value of 100% and a positive predictive value of 99.4%. Area under the ROC curve was .839. The prevalence of PET uptake in arterial walls in a consecutive population of asymptomatic patients is low and usually confined to one type of artery, and its clinical relevance in terms of vulnerability to ischemic events remains to be determined. Copyright © 2012 by the American Society of Neuroimaging.

  13. A theoretical and non-destructive experimental approach for direct inclusion of measured collagen orientation and recruitment into mechanical models of the artery wall.

    Science.gov (United States)

    Hill, Michael R; Duan, Xinjie; Gibson, Gregory A; Watkins, Simon; Robertson, Anne M

    2012-03-15

    Gradual collagen recruitment has been hypothesized as the underlying mechanism for the mechanical stiffening with increasing stress in arteries. In this work, we investigated this hypothesis in eight rabbit carotid arteries by directly measuring the distribution of collagen recruitment stretch under increasing circumferential loading using a custom uniaxial (UA) extension device combined with a multi-photon microscope (MPM). This approach allowed simultaneous mechanical testing and imaging of collagen fibers without traditional destructive fixation methods. Fiber recruitment was quantified from 3D rendered MPM images, and fiber orientation was measured in projected stacks of images. Collagen recruitment was observed to initiate at a finite strain, corresponding to a sharp increase in the measured mechanical stiffness, confirming the previous hypothesis and motivating the development of a new constitutive model to capture this response. Previous constitutive equations for the arterial wall have modeled the collagen contribution with either abrupt recruitment at zero strain, abrupt recruitment at finite strain or as gradual recruitment beginning at infinitesimal strain. Based on our experimental data, a new combined constitutive model was presented in which fiber recruitment begins at a finite strain with activation stretch represented by a probability distribution function. By directly including this recruitment data, the collagen contribution was modeled using a simple Neo-Hookean equation. As a result, only two phenomenological material constants were required from the fit to the stress stretch data. Three other models for the arterial wall were then compared with these results. The approach taken here was successful in combining stress-strain analysis with simultaneous microstructural imaging of collagen recruitment and orientation, providing a new approach by which underlying fiber architecture may be quantified and included in constitutive equations. Copyright

  14. Evolución de los modelos constitutivos de respuesta pasiva para paredes arteriales//Evolution of constitutive models for passive response of the arterial walls

    Directory of Open Access Journals (Sweden)

    Guillermo Fernández‐Collazo

    2014-08-01

    Full Text Available La respuesta mecánica de las paredes arteriales se modifica como consecuencia del envejecimiento y el desarrollo de enfermedades. Estos cambios se ven reflejados en modificaciones en su estructura, composición, resistencia y forma. La predicción de su comportamiento en dependencia de su estado fisiológico usando modelos biomecánicos se muestra como una potente herramienta en el tratamiento y diagnóstico de aneurismas, ateroesclerosis, hipertensión arterial entre otras. Realizando un profundo análisis de la literatura consultada se presenta un estudio bibliográfico de los modelos constitutivos de paredes arteriales en su respuesta pasiva, clasificándolos y destacando sus principales ventajas, desventajas y la evolución de estos desde los puramente fenomenológicos hasta los más complejos.Palabras claves: modelos, arterias, respuesta pasiva, biomecánica._______________________________________________________________________________AbstractThe mechanical response of arterial walls is modified as a result of aging and disease development. These changes are reflected in changes in its composition, strength, shape and structure. The prediction of their behavior, depending on their physiological state used biomechanical models is shown as a powerful tool in the treatment and diagnosis of aneurysms, atherosclerosis, hypertensionand others. It´s presented in its passive response, a profound analysis of the literature and the bibliographic review of the constitutive models of arterial walls, classifying and highlighting their main advantages, disadvantages and the  volution from purely phenomenological to the most complex response.Key words: models, artery, passive response, biomechanics.

  15. No evidence of parvovirus B19, Chlamydia pneumoniae or human herpes virus infection in temporal artery biopsies in patients with giant cell arteritis

    DEFF Research Database (Denmark)

    Helweg-Larsen, J; Tarp, B; Obel, N

    2002-01-01

    using the polymerase chain reaction (PCR). METHODS: Thirty temporal artery biopsies from 30 patients suspected of having GCA within a period of 1 yr were examined. Thirteen patients had classical GCA, two had biopsy-negative GCA, 10 patients had polymyalgia rheumatica and five patients had other...... conditions. DNA was extracted from frozen biopsies and PCR was used to amplify genes from Chlamydia pneumoniae, parvovirus B19 and each of the eight human herpes viruses: herpes simplex viruses HSV-1 and 2, Epstein-Barr virus, cytomegalovirus, varicella zoster virus and human herpes viruses HHV-6, -7 and -8....... RESULTS: In all 30 biopsies, PCR was negative for DNAs of parvovirus B19, each of the eight human herpes viruses and C. pneumoniae. CONCLUSIONS: We found no evidence of DNA from parvovirus B19, human herpes virus or C. pneumoniae in any of the temporal arteries. These agents do not seem to play a unique...

  16. Wall-based measurement features provides an improved IVUS coronary artery risk assessment when fused with plaque texture-based features during machine learning paradigm.

    Science.gov (United States)

    Banchhor, Sumit K; Londhe, Narendra D; Araki, Tadashi; Saba, Luca; Radeva, Petia; Laird, John R; Suri, Jasjit S

    2017-12-01

    Planning of percutaneous interventional procedures involves a pre-screening and risk stratification of the coronary artery disease. Current screening tools use stand-alone plaque texture-based features and therefore lack the ability to stratify the risk. This IRB approved study presents a novel strategy for coronary artery disease risk stratification using an amalgamation of IVUS plaque texture-based and wall-based measurement features. Due to common genetic plaque makeup, carotid plaque burden was chosen as a gold standard for risk labels during training-phase of machine learning (ML) paradigm. Cross-validation protocol was adopted to compute the accuracy of the ML framework. A set of 59 plaque texture-based features was padded with six wall-based measurement features to show the improvement in stratification accuracy. The ML system was executed using principle component analysis-based framework for dimensionality reduction and uses support vector machine classifier for training and testing-phases. The ML system produced a stratification accuracy of 91.28%, demonstrating an improvement of 5.69% when wall-based measurement features were combined with plaque texture-based features. The fused system showed an improvement in mean sensitivity, specificity, positive predictive value, and area under the curve by: 6.39%, 4.59%, 3.31% and 5.48%, respectively when compared to the stand-alone system. While meeting the stability criteria of 5%, the ML system also showed a high average feature retaining power and mean reliability of 89.32% and 98.24%, respectively. The ML system showed an improvement in risk stratification accuracy when the wall-based measurement features were fused with the plaque texture-based features. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Spatio-temporal diversification of the cell wall matrix materials in the developing stomatal complexes of Zea mays.

    Science.gov (United States)

    Giannoutsou, E; Apostolakos, P; Galatis, B

    2016-11-01

    The matrix cell wall materials, in developing Zea mays stomatal complexes are asymmetrically distributed, a phenomenon appearing related to the local cell wall expansion and deformation, the establishment of cell polarity, and determination of the cell division plane. In cells of developing Zea mays stomatal complexes, definite cell wall regions expand determinately and become locally deformed. This differential cell wall behavior is obvious in the guard cell mother cells (GMCs) and the subsidiary cell mother cells (SMCs) that locally protrude towards the adjacent GMCs. The latter, emitting a morphogenetic stimulus, induce polarization/asymmetrical division in SMCs. Examination of immunolabeled specimens revealed that homogalacturonans (HGAs) with a high degree of de-esterification (2F4- and JIM5-HGA epitopes) and arabinogalactan proteins are selectively distributed in the extending and deformed cell wall regions, while their margins are enriched with rhamnogalacturonans (RGAs) containing highly branched arabinans (LM6-RGA epitope). In SMCs, the local cell wall matrix differentiation constitutes the first structural event, indicating the establishment of cell polarity. Moreover, in the premitotic GMCs and SMCs, non-esterified HGAs (2F4-HGA epitope) are preferentially localized in the cell wall areas outlining the cytoplasm where the preprophase band is formed. In these areas, the forthcoming cell plate fuses with the parent cell walls. These data suggest that the described heterogeneity in matrix cell wall materials is probably involved in: (a) local cell wall expansion and deformation, (b) the transduction of the inductive GMC stimulus, and (c) the determination of the division plane in GMCs and SMCs.

  18. Spatial and temporal scales of force and torque acting on wall-mounted spherical particles in open channel flow

    OpenAIRE

    Chan-Braun, Clemens; Garcia-Villalba, Manuel; Uhlmann, Markus

    2013-01-01

    Data from direct numerical simulation of open channel flow over a geometrically rough wall at a bulk Reynolds number of 2900, generated by Chan-Braun et al. ["Force and torque acting on particles in a transitionally rough open-channel flow", J. Fluid Mech. 684, 441--474 (2011), 10.1017/jfm.2011.311] are further analysed with respect to the time and length scales of force and torque acting on the wall-mounted spheres. For the two sizes of spheres in a square arrangement (11 and 49 wall units i...

  19. Early and noninvasive evaluation using superficial temporal artery duplex ultrasonography after indirect bypass for adult ischemic moyamoya disease.

    Science.gov (United States)

    Ogawa, Sayaka; Abe, Hiroshi; Katsuta, Toshiro; Fukuda, Kenji; Ogata, Toshiyasu; Miki, Koichi; Inoue, Tooru

    2017-03-01

    The validity of indirect bypass for adult patients with moyamoya disease is still debatable. Some patients are poor responders to indirect bypass, and additive intervention is occasionally required in these cases. Therefore, it is necessary to evaluate the development of collateral circulation as early as possible postoperatively. Fifteen adult patients (>17 years old) with moyamoya disease (22 affected sides) who underwent encephalo-duro-arterio-synangiosis (EDAS) at Fukuoka University Hospital from April 2008 to August 2014 were included. All patients had ischemic symptoms of at least one hemisphere. Superficial temporal artery duplex ultrasonography (STDU) was performed before and 3, 6, and 12 months postoperatively. Digital subtraction angiography was performed 1 year after the operation to evaluate the development of collateral circulation. Hemispheres exhibiting collateral formation of more than one-third of the MCA distribution were defined as good responders, and those with less than one-third were defined as poor responders. EDAS induced the formation of well-developed collaterals in 17 of 22 affected sides (77.3%) of adult patients with ischemic moyamoya disease. Regardless of the degree of collateral formation, the ischemic event subsided eventually with time in all patients. In good responders, the pulsatility index obtained by STDU showed a drastic decrease 3 months after the operation, while it did not change significantly in poor responders. Absence of this decrease in the pulsatility index along with no change in the flow velocity reliably indicated poor responders. Neovascularization after EDAS can be evaluated noninvasively in early phase using STDU.

  20. Image quality of mean temporal arterial and mean temporal portal venous phase images calculated from low dose dynamic volume perfusion CT datasets in patients with hepatocellular carcinoma and pancreatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X. [Radiology Department, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing (China); Henzler, T., E-mail: thomas.henzler@medma.uni-heidelberg.de [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Gawlitza, J.; Diehl, S. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Wilhelm, T. [Department of Surgery, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Schoenberg, S.O. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany); Jin, Z.Y.; Xue, H.D. [Radiology Department, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing (China); Smakic, A. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University (Germany)

    2016-11-15

    Purpose: Dynamic volume perfusion CT (dVPCT) provides valuable information on tissue perfusion in patients with hepatocellular carcinoma (HCC) and pancreatic cancer. However, currently dVPCT is often performed in addition to conventional CT acquisitions due to the limited morphologic image quality of dose optimized dVPCT protocols. The aim of this study was to prospectively compare objective and subjective image quality, lesion detectability and radiation dose between mean temporal arterial (mTA) and mean temporal portal venous (mTPV) images calculated from low dose dynamic volume perfusion CT (dVPCT) datasets with linearly blended 120-kVp arterial and portal venous datasets in patients with HCC and pancreatic cancer. Materials and methods: All patients gave written informed consent for this institutional review board–approved HIPAA compliant study. 27 consecutive patients (18 men, 9 women, mean age, 69.1 years ± 9.4) with histologically proven HCC or suspected pancreatic cancer were prospectively enrolled. The study CT protocol included a dVPCT protocol performed with 70 or 80 kVp tube voltage (18 spiral acquisitions, 71.2 s total acquisition times) and standard dual-energy (90/150 kVpSn) arterial and portal venous acquisition performed 25 min after the dVPCT. The mTA and mTPV images were manually reconstructed from the 3 to 5 best visually selected single arterial and 3 to 5 best single portal venous phases dVPCT dataset. The linearly blended 120-kVp images were calculated from dual-energy CT (DECT) raw data. Image noise, SNR, and CNR of the liver, abdominal aorta (AA) and main portal vein (PV) were compared between the mTA/mTPV and the linearly blended 120-kVp dual-energy arterial and portal venous datasets, respectively. Subjective image quality was evaluated by two radiologists regarding subjective image noise, sharpness and overall diagnostic image quality using a 5-point Likert Scale. In addition, liver lesion detectability was performed for each liver

  1. Genetic variation within the Y chromosome is not associated with histological characteristics of the atherosclerotic carotid artery or aneurysmal wall

    NARCIS (Netherlands)

    Haitjema, Saskia; van Setten, Jessica|info:eu-repo/dai/nl/345493990; Eales, James; van der Laan, Sander W|info:eu-repo/dai/nl/314003045; Gandin, Ilaria; de Vries, Jean-Paul P M; de Borst, Gert J|info:eu-repo/dai/nl/237108151; Pasterkamp, Gerard|info:eu-repo/dai/nl/138488304; Asselbergs, Folkert W|info:eu-repo/dai/nl/270752137; Charchar, Fadi J; Wilson, James F; de Jager, Saskia C A|info:eu-repo/dai/nl/314952799; Tomaszewski, Maciej; den Ruijter, Hester M|info:eu-repo/dai/nl/304123846

    BACKGROUND AND AIMS: Haplogroup I, a common European paternal lineage of the Y chromosome, is associated with increased risk of coronary artery disease in British men. It is unclear whether this haplogroup or any other haplogroup on the Y chromosome is associated with histological characteristics of

  2. Micro-CT image-derived metrics quantify arterial wall distensibility reduction in a rat model of pulmonary hypertension

    Science.gov (United States)

    Johnson, Roger H.; Karau, Kelly L.; Molthen, Robert C.; Haworth, Steven T.; Dawson, Christopher A.

    2000-04-01

    We developed methods to quantify arterial structural and mechanical properties in excised rat lungs and applied them to investigate the distensibility decrease accompanying chronic hypoxia-induced pulmonary hypertension. Lungs of control and hypertensive (three weeks 11% O2) animals were excised and a contrast agent introduced before micro-CT imaging with a special purpose scanner. For each lung, four 3D image data sets were obtained, each at a different intra-arterial contrast agent pressure. Vessel segment diameters and lengths were measured at all levels in the arterial tree hierarchy, and these data used to generate features sensitive to distensibility changes. Results indicate that measurements obtained from 3D micro-CT images can be used to quantify vessel biomechanical properties in this rat model of pulmonary hypertension and that distensibility is reduced by exposure to chronic hypoxia. Mechanical properties can be assessed in a localized fashion and quantified in a spatially-resolved way or as a single parameter describing the tree as a whole. Micro-CT is a nondestructive way to rapidly assess structural and mechanical properties of arteries in small animal organs maintained in a physiological state. Quantitative features measured by this method may provide valuable insights into the mechanisms causing the elevated pressures in pulmonary hypertension of differing etiologies and should become increasingly valuable tools in the study of complex phenotypes in small-animal models of important diseases such as hypertension.

  3. Analysis of Varicella-Zoster Virus in Temporal Arteries Biopsy Positive and Negative for Giant Cell Arteritis.

    Science.gov (United States)

    Nagel, Maria A; White, Teresa; Khmeleva, Nelly; Rempel, April; Boyer, Philip J; Bennett, Jeffrey L; Haller, Andrea; Lear-Kaul, Kelly; Kandasmy, Balasurbramaniyam; Amato, Malena; Wood, Edward; Durairaj, Vikram; Fogt, Franz; Tamhankar, Madhura A; Grossniklaus, Hans E; Poppiti, Robert J; Bockelman, Brian; Keyvani, Kathy; Pollak, Lea; Mendlovic, Sonia; Fowkes, Mary; Eberhart, Charles G; Buttmann, Mathias; Toyka, Klaus V; Meyer-ter-Vehn, Tobias; Petursdottir, Vigdis; Gilden, Don

    2015-11-01

    Giant cell arteritis (GCA) is the most common systemic vasculitis in elderly individuals. Diagnosis is confirmed by temporal artery (TA) biopsy, although biopsy results are often negative. Despite the use of corticosteroids, disease may progress. Identification of causal agents will improve outcomes. Biopsy-positive GCA is associated with TA infection by varicella-zoster virus (VZV). To analyze VZV infection in TAs of patients with clinically suspected GCA whose TAs were histopathologically negative and in normal TAs removed post mortem from age-matched individuals. A cross-sectional study for VZV antigen was performed from January 2013 to March 2015 using archived, deidentified, formalin-fixed, paraffin-embedded GCA-negative, GCA-positive, and normal TAs (50 sections/TA) collected during the past 30 years. Regions adjacent to those containing VZV were examined by hematoxylin-eosin staining. Immunohistochemistry identified inflammatory cells and cell types around nerve bundles containing VZV. A combination of 17 tertiary referral centers and private practices worldwide contributed archived TAs from individuals older than 50 years. Presence and distribution of VZV antigen in TAs and histopathological changes in sections adjacent to those containing VZV were confirmed by 2 independent readers. Varicella-zoster virus antigen was found in 45 of 70 GCA-negative TAs (64%), compared with 11 of 49 normal TAs (22%) (relative risk [RR] = 2.86; 95% CI, 1.75-5.31; P Varicella-zoster virus antigen was frequently found in perineurial cells expressing claudin-1 around nerve bundles. Of 45 GCA-negative participants whose TAs contained VZV antigen, 1 had histopathological features characteristic of GCA, and 16 (36%) showed adventitial inflammation adjacent to viral antigen; no inflammation was seen in normal TAs. In patients with clinically suspected GCA, prevalence of VZV in their TAs is similar independent of whether biopsy results are negative or positive pathologically

  4. Spatial and temporal scales of force and torque acting on wall-mounted spherical particles in open channel flow

    Science.gov (United States)

    Chan-Braun, C.; García-Villalba, M.; Uhlmann, M.

    2013-07-01

    Data from direct numerical simulation of open channel flow over a geometrically rough wall at a bulk Reynolds number of Reb = 2900, generated by Chan-Braun et al. ["Force and torque acting on particles in a transitionally rough open-channel flow," J. Fluid Mech. 684, 441-474 (2011)], 10.1017/jfm.2011.311 are further analysed with respect to the time and length scales of force and torque acting on the wall-mounted spheres. For the two sizes of spheres in a square arrangement (11 and 49 wall units in diameter, yielding hydraulically smooth and transitionally rough flow, respectively), the spatial structure of drag, lift, and spanwise torque is investigated. The auto-correlation and spectra in time as well as the space-time correlation and convection velocities are presented and discussed. It is found that the statistics of spanwise particle torque are similar to those of shear stress at a smooth wall. Particle drag and lift are shown to differ from spanwise particle torque, exhibiting considerably smaller time and length scales; the convection velocities of drag and lift are somewhat larger than those of spanwise torque. Furthermore, correlations between the flow field and particle-related quantities are presented. The spatial structure of the correlation between streamwise velocity and drag/spanwise torque features elongated shapes reminiscent of buffer-layer streaks. The correlation between the pressure field and the particle drag exhibits two opposite-signed bulges on the upstream and downstream sides of a particle.

  5. Role of the structural elements of the arterial wall in the formation and growth of intracranial saccular aneurysms.

    Science.gov (United States)

    Mérei, F T; Gallyas, F

    1980-01-01

    Besides apical medial gaps, lateral and circular medial gaps can be found occasionally at the branching sites of human intracranial arteries, supporting Forbus's idea (1930) of their mechanism of formation and contradicting those put forward by later workers. The large medial gaps situated just distal to the branching sites, considered by Stehbens (1963) to be degenerative in origin, may result from enlargement of congenital multiple apical gaps. Degeneration of the internal elastic layer in the area of medial gaps consists in enlargement and partial fusion of its "physiologic" windows. In contrast to the prevailing opinion, human intracranial arteries do have a well-developed external elastic layer whose density gradually decreases with increasing lengths of the medial gaps. The fundus of a mature aneurysm generally contains no continuous elastic membrane or fiber and relatively little granular elastic material. The equilibrium between partial degeneration and steady reformation of adventitial collagen fibers makes possible the growth of an aneurysm. The thickening of the aneurysmal intima appears to be in causal relationship with the stagnation zones existing in larger aneurysms. In special cases small islets of the arterial media can get into the fundus of an aneurysm, whose spindle-like smooth muscle cells, arranged in a parallel manner, may dissociate themselves from each other and be transformed into spider-like cells.

  6. Comparison between Carotid Artery Wall Thickness Measured by Multidetector Row Computed Tomography Angiography and Intimae-Media Thickness Measured by Sonography

    Directory of Open Access Journals (Sweden)

    Živorad N. Savić

    2011-01-01

    Full Text Available The increased thickness of the carotid wall >1 mm is a significant predictor of coronary and cerebrovascular diseases. The purpose of our study was to assess the agreement between multidetector row computed tomography angiography (MDCTA in measuring carotid artery wall thickness (CAWT and color Doppler ultrasound (CD-US in measuring intimae-media thickness (IMT. Eighty-nine patients (aged 35–81 were prospectively analyzed using a 64-detector MDCTA and a CD-US scanner. Continuous data were described as the mean value ± standard deviation, and were compared using the Mann–Whitney U test. A p value <0.05 was considered significant. Bland–Altman statistics were employed to measure the agreement between MDCTA and CD-US. CAWT ranged from 0.62 to 1.60 mm, with a mean value of 1.09 mm. IMT ranged from 0.60 to 1.55 mm, with a mean value of 1.06 mm. We observed an excellent agreement between CD-US and MDCTA in the evaluation of the common carotid artery thickness, with a bias between methods of 0.029 mm (which is a highly statistically important difference of absolute values [t = 43.289; p < 0.01] obtained by paired T test, and limits of agreement from 0.04 to 0.104. Pearson correlation coefficient was 0.9997 (95% CI 0.9996–0.9998; p < 0.01. We conclude that there is an excellent correlation between CAWT and IMT measurements obtained with the MDCTA and CD-US.

  7. Evaluation and comparison of {sup 11}C-choline uptake and calcification in aortic and common carotid arterial walls with combined PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Katsuhiko [University of Muenster, Department of Nuclear Medicine, Muenster (Germany); Nagoya University Graduate School of Medicine, Department of Radiology, Nagoya (Japan); Nagoya University School of Health Sciences, Department of Radiological Technology, Nagoya (Japan); Schober, Otmar; Kies, Peter; Stegger, Lars [University of Muenster, Department of Nuclear Medicine, Muenster (Germany); Ikeda, Mitsuru [Nagoya University School of Health Sciences, Department of Radiological Technology, Nagoya (Japan); Schaefers, Michael [University of Muenster, European Institute of Molecular Imaging, Muenster (Germany); Ishigaki, Takeo; Naganawa, Shinji [Nagoya University Graduate School of Medicine, Department of Radiology, Nagoya (Japan)

    2009-10-15

    Inflamed atherosclerotic plaques may rupture and cause acute myocardial infarction, stroke and other thrombotic events. Early detection of these unstable plaques could, in many cases, prevent such potentially fatal events. {sup 11}C-choline or {sup 18}F-labelled choline derivatives for visualizing the synthesis of phospholipids, are promising markers of plaque inflammation with potential advantages over {sup 18}F-FDG. Their potential for plaque characterization in humans is, however, unclear. In this study the prevalence and distribution of {sup 11}C-choline uptake in the aortic and common carotid arterial walls of elderly male patients was evaluated with combined PET/CT. Additionally, the localization of radiotracer uptake and calcification was correlated in various vessel segments. Image data from 93 consecutive male patients between 60 and 80 years old who had undergone whole-body {sup 11}C-choline PET/CT assessment for prostate cancer were evaluated retrospectively. {sup 11}C-choline uptake and calcification were analysed qualitatively and semiquantitatively and compared. {sup 11}C-choline uptake was found in 95% of patients, calcification in 94% throughout all vessel segments. In 6% of the patients radiotracer uptake was colocalized with calcifications, whereas less than 1% of calcification sites showed increased radiotracer uptake. Both {sup 11}C-choline uptake and calcification in the aortic and common carotid arterial walls are common in elderly men. Radiotracer uptake and calcification are, however, only rarely colocalized. {sup 11}C-choline has the potential to provide information about atherosclerotic plaques independent of calcification measurement. (orig.)

  8. Flow and wall shear stress in end-to-side and side-to-side anastomosis of venous coronary artery bypass grafts

    Directory of Open Access Journals (Sweden)

    Poulikakos Dimos

    2007-09-01

    Full Text Available Abstract Purpose Coronary artery bypass graft (CABG surgery represents the standard treatment of advanced coronary artery disease. Two major types of anastomosis exist to connect the graft to the coronary artery, i.e., by using an end-to-side or a side-to-side anastomosis. There is still controversy because of the differences in the patency rates of the two types of anastomosis. The purpose of this paper is to non-invasively quantify hemodynamic parameters, such as mass flow and wall shear stress (WSS, in end-to-side and side-to-side anastomoses of patients with CABG using computational fluid dynamics (CFD. Methods One patient with saphenous CABG and end-to-side anastomosis and one patient with saphenous CABG and side-to-side anastomosis underwent 16-detector row computed tomography (CT. Geometric models of coronary arteries and bypasses were reconstructed for CFD analysis. Blood flow was considered pulsatile, laminar, incompressible and Newtonian. Peri-anastomotic mass flow and WSS were quantified and flow patterns visualized. Results CFD analysis based on in-vivo CT coronary angiography data was feasible in both patients. For both types of CABG, flow patterns were characterized by a retrograde flow into the native coronary artery. WSS variations were found in both anastomoses types, with highest WSS values at the heel and lowest WSS values at the floor of the end-to-side anastomosis. In contrast, the highest WSS values of the side-to-side anastomosis configuration were found in stenotic vessel segments and not in the close vicinity of the anastomosis. Flow stagnation zones were found in end-to-side but not in side-to-side anastomosis, the latter also demonstrating a smoother stream division throughout the cardiac cycle. Conclusion CFD analysis of venous CABG based on in-vivo CT datasets in patients was feasible producing qualitative and quantitative information on mass flow and WSS. Differences were found between the two types of anastomosis

  9. A novel four-dimensional angiographic approach to assess dynamic superficial wall stress of coronary arteries in vivo

    DEFF Research Database (Denmark)

    Wu, Xinlei; von Birgelen, Clemens; Muramatsu, Takashi

    2017-01-01

    it for the first time in two clinical cases to investigate the potential relationship between dynamic stress concentration at baseline and plaque rupture during acute coronary syndrome (ACS) several months later. METHODS AND RESULTS: Three-dimensional angiographic reconstructions of the interrogated arteries were...... performed at several phases of the cardiac cycle, followed by finite element analysis to obtain the dynamic SWS data. The peak stress at baseline was found at the distal and proximal lesion longitudinal shoulders, being 121.8kPa and 98.0kPa, respectively. Intriguingly, in both cases, the sites...

  10. RGC-32 is expressed in the human atherosclerotic arterial wall: Role in C5b-9-induced cell proliferation and migration.

    Science.gov (United States)

    Vlaicu, Sonia I; Tatomir, Alexandru; Boodhoo, Dallas; Ito, Takahiro; Fosbrink, Matthew; Cudrici, Cornelia; Mekala, Armugam P; Ciriello, Jonathan; Crişan, Doiniţa; Boţan, Emil; Rus, Violeta; Rus, Horea

    2016-10-01

    The complement system is an important player in the development of atherosclerosis. Previously reported as a cell cycle regulator, RGC-32 is an essential effector of the terminal complement complex, C5b-9. In this study, our aims were to determine the expression of RGC-32 in the human atherosclerotic arterial wall and to delineate the mechanisms through which RGC-32 affects C5b-9-induced endothelial cell proliferation and migration. We now demonstrate that RGC-32 is expressed in human aortic atherosclerotic wall and that RGC-32 expression increases with the progression of atherosclerosis. Furthermore, silencing of RGC-32 expression abolished C5b-9-induced human aortic endothelial cell (HAEC) proliferation and migration. Of the 279 genes differentially expressed in HAECs after RGC-32 silencing, the genes involved in cell adhesion and cell cycle activation were significantly regulated by RGC-32. RGC-32 silencing caused a significant reduction in the expression of cyclin D1, cyclin D3, Akt, ROCK1, Rho GDP dissociation inhibitor alpha and profilin. These data suggest that RGC-32 mediates HAEC migration through the regulation of RhoA and ROCK1 expression and is involved in actin cytoskeletal organization. Thus, RGC-32 has promising therapeutic potential with regard to angiogenesis and atherosclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. A Rare Case of Giant Basal Cell Carcinoma of the Abdominal Wall: Excision and Immediate Reconstruction with a Pedicled Deep Inferior Epigastric Artery Perforator (DIEP) Flap.

    Science.gov (United States)

    Di Lorenzo, Sara; Zabbia, Giovanni; Corradino, Bartolo; Tripoli, Massimiliano; Pirrello, Roberto; Cordova, Adriana

    2017-12-04

    BACKGROUND Basal cell carcinoma (BCC) greater than 5 cm in diameter is called giant basal cell carcinoma (GBCC), or super giant basal cell carcinoma if it has a diameter larger than 20 cm. Giant BCC only accounts for 0.5% of BCCs and super giant BCC is exceedingly rare. On account of their rarity, there are no established guidelines for GBCC treatment. CASE REPORT We describe a peculiar case of an 82-year-old woman with a GBCC carcinoma of the lower abdominal wall. The tumor was surgically removed with ipsilateral inguinal lymph nodes and the abdominal wall was reconstructed immediately with a pedicled deep inferior epigastric artery perforator (DIEP) flap. CONCLUSIONS Treatment of giant basal cell carcinoma is often difficult, especially in elderly patients with poor general health and multiple pathologies. The pedicled DIEP flap is rotated to cover the loss of substance without tension, and it is easy to harvest and transfer. This flap allowed a good result without local or systemic complication. We present this report as a reminder of the occasional occurrence of extremely aggressive BCCs. We believe that, especially for rare tumors like these, it is very useful for the entire scientific community to publish these cases and the therapeutic strategies used to treat them.

  12. Vascularization of the facial bones by the facial artery: implications for full face allotransplantation.

    Science.gov (United States)

    Gharb, Bahar Bassiri; Rampazzo, Antonio; Kutz, Joseph E; Bright, Linda; Doumit, Gaby; Harter, Thomas B

    2014-05-01

    The maxillary artery is recognized as the main vascular supply of the facial bones; nonetheless, clinical evidence supports a codominant role for the facial artery. This study explores the extent of the facial skeleton within a facial allograft that can be harvested based on the facial artery. Twenty-three cadaver heads were used in this study. In 12 heads, the facial, superficial temporal, and maxillary arteries were injected. In one head, facial artery angiography was performed. Ten facial allografts were raised. The soft tissues were dissected to show the arterial anastomotic connections. Radiographs and computed tomographic scans were obtained. Constant anastomosis between the facial, inferior alveolar, and infraorbital arteries at the mental and infraorbital foramina were found. The facial artery vascularized the homolateral mandibular symphysis, body, and ramus. The condylar and coronoid processes were vascularized in 67 percent of the allografts. The homolateral maxilla was contrasted in all allografts. The alveolar and palatine processes contained the contrast in 83 percent of specimens. The maxillary process of the zygomatic bone was perfused in all allografts, followed by the body, frontal (83 percent), and temporal processes (67 percent). The nasal lateral wall and septum were vascularized in 83 percent of the allografts. The medial and lateral orbital walls and the orbital floor were stained in all specimens. The zygomatic process of the temporal bone was the least perfused bone. A composite allograft containing 90 to 95 percent of the facial bones can be based on bilateral facial arteries.

  13. Numerical study of spatial-temporal evolution of the secondary flow in the models of a common carotid artery

    Directory of Open Access Journals (Sweden)

    Yakov A. Gataulin

    2017-03-01

    Full Text Available A numerical study of the secondary flow in two geometrically different models of a common carotid artery has been carried out. One of the models (Model 1 is characterized by a statistically averaged curvature, and the second one (Model 2 is attributed to the maximal curvature of the artery. It was shown that the most intensive swirl occurred at the phase of flow rate decreasing, the maximum values of the swirl parameters were observed at the interface of the cervical and thoracic segments of the artery. This interface is the place where the Dean vortices are transformed into a single vortex forming a swirling flow. The swirl intensity averaged over the systole and characterized by the ratio of the maximal values of the axial and circumferential velocities was evaluated as 0.20 for Model 1 and 0.25 for Model 2. Generally, it was in accordance with the data of clinical measurements.

  14. The usefulness of the ivy sign on fluid-attenuated intensity recovery images in improved brain hemodynamic changes after superficial temporal artery-middle cerebral artery anastomosis in adult patients with moyamoya disease.

    Science.gov (United States)

    Lee, Jung Keun; Yoon, Byul Hee; Chung, Seung Young; Park, Moon Sun; Kim, Seong Min; Lee, Do Sung

    2013-10-01

    MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images. We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery. Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis. After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.

  15. "Sausage-string" appearance of arteries and arterioles can be caused by an instability of the blood vessel wall

    DEFF Research Database (Denmark)

    Jacobsen, Jens Christian Brings; Beierholm, Ulrik; Mikkelsen, Rene

    2002-01-01

    Vascular damage induced by acute hypertension is preceded by a peculiar pattern where blood vessels show alternating regions of constrictions and dilations ("sausages on a string"). The pattern occurs in the smaller blood vessels, and it plays a central role in causing the vascular damage....... A related vascular pattern has been observed in larger vessels from several organs during angiography. In the larger vessels the occurrence of the pattern does not appear to be related to acute hypertension. A unifying feature between the phenomenon in large and small vessels seems to be an increase...... observed experimentally. Most importantly, it suggests that the "sausaging" phenomenon is neither caused by a mechanical failure of the vessel wall due to a high blood pressure nor is it due to standing pressure waves caused by the beating of the heart. Rather, it is the expression of a general instability...

  16. Temporal profile of the effects of intracisternal injection of magnesium sulfate solution on vasodilation of spastic cerebral arteries in the canine SAH model.

    Science.gov (United States)

    Mori, Kentaro; Miyazaki, Masahiro; Hara, Yasukazu; Aiko, Yasuhisa; Yamamoto, Takuji; Nakao, Yasuaki; Esaki, Takanori

    2011-01-01

    the temporal profiles of the effects of intracisternal injection of magnesium sulfate (MgSO(4)) on vasodilation and cerebrospinal fluid (CSF) magnesium ion (Mg(2+)) concentration were investigated in the canine subarachnoid hemorrhage (SAH) model. cerebral vasospasm was induced using the two-hemorrhage model in seven female beagles. On day 7, 0.5 ml/kg of 15 mmol/l MgSO(4) in Ringer solution was injected into the cerebellomedullary cistern. Angiography was performed on day 1 (before SAH), and before and 1, 3, and 6 h after the intracisternal injection on day 7. CSF Mg(2+) was measured at the same time. the diameters of the basilar artery (BA), vertebral artery (VA), and superior cerebellar artery (SCA) before the intracisternal injection on day 7 were 0.59 ± 0.15, 0.41 ± 0.17, and 0.35 ± 0.17 mm, respectively, and were significantly decreased (p < 0.01) compared with the baseline diameters on day 1. The BA diameters at 1 h (0.74 ± 0.16 mm) and 3 h (0.73 ± 0.13 mm), the VA diameter at 1 h (0.64 ± 0.14 mm), and the SCA diameter at 3 h (0.54 ± 0.08 mm) after the injection were significantly increased (p < 0.05). The CSF Mg(2+) concentration was significantly increased (p < 0.01) at 1 h (3.59 ± 0.76 mEq/l) and 3 h (2.00 ± 0.31 mEq/l) after the injection compared with the baseline value (1.35 ± 0.23 mEq/l). the reversible effect of intracisternal MgSO(4) solution injection on the spastic artery depends on maintenance of the optimal CSF Mg(2+) concentration.

  17. Histopathological changes of radial artery wall in patients of chronic kidney disease stage 5 undergoing Av fistula formation and their correlation with serum iPTH levels

    Directory of Open Access Journals (Sweden)

    Vidyanand Tripathi

    2015-01-01

    Full Text Available Vascular complications arise in uremic patients in the absence of clinically significant atherosclerotic disease. Elevated serum parathyroid hormone (PTH and abnormal calcium (Ca and phosphorus (P balance have been implicated in vascular damage in chronic kidney disease (CKD patients, but there is lack of histo-pathological studies. Patients with CKD stage 5 and 5D who underwent arterio-venous fistula were included in this study. Baseline and laboratory parameters including assessment of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, albumin, calcium, phosphorus, intact PTH (iPTH and vitamin D level were documented. The specimens of the arterial wall were obtained during the procedure and were analyzed. Patients were divided into two groups iPTH 400 (Group B. Mean intimal thickness (IT was significantly high in patients of Group B (60.4 ± 24.1 μ m as compared with patients of Group A (37.8 ± 14.9 μm (P = 0.003. Vascular calcification was comparable in both groups. The iPTH level was found to be an independent risk factor for high intima thickness (correlation coefficient 0.653 (P-value <0.01. Patients with high (≥400 pg/mL iPTH have 8.93 times the risk of developing intimal thickness of ≥60 μ m as compared with patients with low (<400 pg/mL iPTH (P-value <0.05, with 95% confidence interval of 1.27, 62.61. The mean IT of the radial artery significantly correlated with the iPTH level, while vascular calcification was independent of the iPTH level. Hyperparathyroidism is an important cause of ongoing vascular damage and may contribute to higher vascular events in CKD patients.

  18. {sup 18}F-fluoroethylcholine uptake in arterial vessel walls and cardiovascular risk factors. Correlation in a PET-CT study

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, Stefan; Rominger, A.; Cumming, P.; Bartenstein, P.; Hacker, M. [Technische Univ. Muenchen (TUM) (Germany). Dept. of Nuclear Medicine; Saam, T.; Nikolaou, K.; Reiser, M.F. [Univ. Muenchen (Germany). Inst. of Clinical Radiology; Wolpers, S. [Technische Univ. Muenchen (TUM) (Germany). Dept. of Nuclear Medicine; Univ. Muenchen (Germany). Inst. of Clinical Radiology

    2010-07-01

    Fluorine-labelled choline derivatives were recently suggested as agents for visualizing vulnerable atherosclerotic plaques. We therefore aimed to evaluate the association between {sup 18}F-fluorethylcholine (FEC) uptake in the wall of large arteries, where calcification was also measured, with the presence of cardiovascular risk factors and occurrence of prior cardiovascular events. Detailed clinical information, including common cardiovascular risk factors, was obtained retrospectively in 60 prostate cancer patients examined with whole-body FEC PET-CT. In each patient, we calculated the mean blood pool-corrected SUV, as well as the mean target-to-background ratio (TBR), in addition to the sum of calcified plaques (CP{sub sum}) from six major vessels: ascending and descending aorta, aortic arch, abdominal aorta, and both iliac arteries. As reported previously, the CP{sub sum} correlated significantly with cardiovascular risk factors, in contrast to mean SUV or TBR scores, which did not show any significance with the presence of cardiovascular risk factors. There was no correlation between CP{sub sum}, mean TBR or SUV, nor was there any significant association of CP{sub sum}, mean TBR or SUV with the prior occurrence of cardio- or cerebrovascular events. Contrary to a recent report, we found in our rather large cohort of elderly prostate cancer patients no significant association between FEC uptake in large vessels and atherosclerotic plaque burden, or the presence of cardiovascular risk factors. In line with prior reports on structural changes in vessels, increased calcified atherosclerotic plaque burden was strongly associated with the occurrence of common cardiovascular risk factors. (orig.)

  19. Endovascular repair of arterial iliac vessel wall lesions with a self-expandable nitinol stent graft system.

    Directory of Open Access Journals (Sweden)

    Birger Mensel

    Full Text Available To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs using a self-expandable Nitinol stent graft system.Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications.The primary technical and clinical success rate was 81.3% (13/16 patients and 75.0% (12/16, respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16 and 93.8% (15/16. The minor complication rate was 6.3% (patient with painful hematoma at the access site. The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis. During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed.Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective.

  20. Real-time ultrasound-tagging to track the 2D motion of the common carotid artery wall in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Zahnd, Guillaume, E-mail: g.zahnd@erasmusmc.nl [Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus MC, Rotterdam 3000 CA (Netherlands); Salles, Sébastien; Liebgott, Hervé; Vray, Didier [Université de Lyon, CREATIS, CNRS UMR 5220, INSERM U1044, INSA-Lyon, Université Lyon 1, Lyon 69100 (France); Sérusclat, André [Department of Radiology, Louis Pradel Hospital, Lyon 69500 (France); Moulin, Philippe [Department of Endocrinology, Louis Pradel Hospital, Hospices Civils de Lyon, Université Lyon 1, Lyon 69100, France and INSERM UMR 1060, Lyon 69500 (France)

    2015-02-15

    Purpose: Tracking the motion of biological tissues represents an important issue in the field of medical ultrasound imaging. However, the longitudinal component of the motion (i.e., perpendicular to the beam axis) remains more challenging to extract due to the rather coarse resolution cell of ultrasound scanners along this direction. The aim of this study is to introduce a real-time beamforming strategy dedicated to acquire tagged images featuring a distinct pattern in the objective to ease the tracking. Methods: Under the conditions of the Fraunhofer approximation, a specific apodization function was applied to the received raw channel data, in real-time during image acquisition, in order to introduce a periodic oscillations pattern along the longitudinal direction of the radio frequency signal. Analytic signals were then extracted from the tagged images, and subpixel motion tracking of the intima–media complex was subsequently performed offline, by means of a previously introduced bidimensional analytic phase-based estimator. Results: The authors’ framework was applied in vivo on the common carotid artery from 20 young healthy volunteers and 6 elderly patients with high atherosclerosis risk. Cine-loops of tagged images were acquired during three cardiac cycles. Evaluated against reference trajectories manually generated by three experienced analysts, the mean absolute tracking error was 98 ± 84 μm and 55 ± 44 μm in the longitudinal and axial directions, respectively. These errors corresponded to 28% ± 23% and 13% ± 9% of the longitudinal and axial amplitude of the assessed motion, respectively. Conclusions: The proposed framework enables tagged ultrasound images of in vivo tissues to be acquired in real-time. Such unconventional beamforming strategy contributes to improve tracking accuracy and could potentially benefit to the interpretation and diagnosis of biomedical images.

  1. The changes of individual carotid artery wall layer by aging and carotid intima-media thickness value for high risk.

    Science.gov (United States)

    Bae, Jang-Ho; Kim, Wuon-Shik; Lee, Moo-Sik; Kim, Kee-Sik; Park, Jeong Bae; Youn, Ho-Joong; Park, Chang-Gyu; Hong, Kyung-Soon; Kim, Jang-Young; Jeong, Jin-Won; Park, Jong Chun; Lim, Do-Sun; Kim, Moo Hyun; Woo, Jeong Taek

    2016-12-01

    It is still unclear which layer (intima or media) is mainly involved in increased carotid intima-media thickness (CIMT) by aging and also unclear regarding CIMT value suggesting high cardiovascular risk, although 75th percentile value of CIMT is known as a high risk in asymptomatic adults. We sought to find the changes of carotid intima thickness (CIT) and carotid media thickness (CMT) by aging and the 75th percentile value of CIMT in asymptomatic Korean adults. This is an observational cohort study. Carotid ultrasound findings (n=2204 from 12 hospitals) were prospectively collected. The carotid images were sent to Korea Research Institute of Standards and Science for analysis using specialized software which can measure intima and media wall also. Mean age was 58.1±13.5 years old (52% of men). Pearson's correlation coefficient between age and right CIMT (r=.489, Pvalue was 0.778 and 0.771 mm, respectively. Mean right CIT was 0.311±0.069 and 0.303±0.064 mm (P=.009), and mean right CMT was 0.391±0.124 and 0.388±0.131 mm (P=.694) in male and female, respectively. Left carotid ultrasound findings showed similar to the right one. An increased CIMT by aging was mainly due to increased CMT rather than CIT in asymptomatic adults. The 75th percentile values of right CIMT were 0.778 and 0.771 mm in asymptomatic Korean male and female adults, respectively. © 2016 John Wiley & Sons Ltd.

  2. Biopsia de la arteria temporal: revisión de indicaciones y técnica quirúrgica para cirujanos plásticos Temporal artery biopsy: review of indications and surgical technique for plastic surgeons

    Directory of Open Access Journals (Sweden)

    A. Rodríguez Lorenzo

    2007-06-01

    Full Text Available La arteritis de células gigantes (ACG es una vasculitis que presenta complicaciones graves si no es diagnosticada y tratada precozmente con corticoides a altas dosis. La biopsia de la arteria temporal (BAT es la técnica diagnóstica estandarizada utilizada para confirmar la enfermedad. Se trata de una técnica sencilla y con poca morbilidad. No obstante, en la actualidad existe una controversia sobre su indicación en pacientes con sospecha clínica de arteritis sin síntomas craneales debido a la baja tasa de positividad de la biopsia. Presentamos en este trabajo una serie de 28 pacientes en los que se realizaron 30 BAT con el objetivo de revisar las indicaciones y describir la técnica quirúrgica utilizada.Giant cell arteritis is a vasculitis that presents serious complications if it is not diagnosed and treated prematurely with corticosteroids to high dose. The temporal artery biopsy is the gold estandar technique of diagnosis used to confirm the disease. It is a simple technique with little morbidity. Nevertheless, currently there is a controversy on its indication in patients with clinical suspicion of arteritis without craneal symptoms because of the downward rate of positiveness of the biopsy. We present in this work a serie of 28 patients in which 30 biopsies were carried out with the objective to review the indications and to describe the surgical technique utilized.

  3. Spontaneous confabulation, temporal context confusion and reality monitoring: a study of three patients with anterior communicating artery aneurysms.

    Science.gov (United States)

    Turner, Martha S; Cipolotti, Lisa; Shallice, Tim

    2010-11-01

    Spontaneous confabulation involves the production of false or distorted memories, and is commonly associated with ventromedial prefrontal damage. One influential theory proposes that the critical deficit is a failure to suppress currently irrelevant memory traces that intrude into ongoing thinking (Schnider & Ptak, 1999). In this study, we report experimental investigations with three spontaneously confabulating patients aimed at exploring this account. Using Schnider and Ptak's (1999) continuous recognition paradigm, we replicated their experimental results with our patients. However, our data suggest that the critical impairment might be more generalized than a failure to suppress currently irrelevant memories. First, a temporal source monitoring task failed to show that previous memory traces intrude into the present. Second, a reality monitoring task revealed that confabulating patients had a tendency to misidentify imagined events as real, a result that cannot be explained in terms of temporal confusion. This error was specific to confabulating patients and was not shared by non-confabulating ACoA patients. Our data therefore suggest a more generalized impairment in source monitoring, not only on the basis of temporality or current relevance, but across a range of contextual domains, including information used to distinguish real memories from imaginings.

  4. Isolated single coronary artery (RII-B type presenting as an inferior wall myocardial infarction: A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Ankur C. Thummar

    2014-09-01

    Full Text Available Isolated single coronary artery without other congenital cardiac anomalies is very rare among the different variations of anomalous coronary patterns. The prognosis in patients with single coronary varies according to the anatomic distribution and associated coronary atherosclerosis. If the left main coronary artery travels between the aorta and pulmonary arteries, it may be a cause of sudden cardiac death. We present multimodality images of a single coronary artery, in which the whole coronary system originated by a single trunk from the right sinus of Valsalva with inter-arterial course of left main coronary artery. This rare type of single coronary artery was classified as RII-B type according to Lipton's scheme of classification. A significant flow-limiting lesions were found in the right coronary artery that was successfully treated with percutaneous coronary intervention.

  5. Arterial stiffness and cognitive impairment.

    Science.gov (United States)

    Li, Xiaoxuan; Lyu, Peiyuan; Ren, Yanyan; An, Jin; Dong, Yanhong

    2017-09-15

    Arterial stiffness is one of the earliest indicators of changes in vascular wall structure and function and may be assessed using various indicators, such as pulse-wave velocity (PWV), the cardio-ankle vascular index (CAVI), the ankle-brachial index (ABI), pulse pressure (PP), the augmentation index (AI), flow-mediated dilation (FMD), carotid intima media thickness (IMT) and arterial stiffness index-β. Arterial stiffness is generally considered an independent predictor of cardiovascular and cerebrovascular diseases. To date, a significant number of studies have focused on the relationship between arterial stiffness and cognitive impairment. To investigate the relationships between specific arterial stiffness parameters and cognitive impairment, elucidate the pathophysiological mechanisms underlying the relationship between arterial stiffness and cognitive impairment and determine how to interfere with arterial stiffness to prevent cognitive impairment, we searched PUBMED for studies regarding the relationship between arterial stiffness and cognitive impairment that were published from 2000 to 2017. We used the following key words in our search: "arterial stiffness and cognitive impairment" and "arterial stiffness and cognitive impairment mechanism". Studies involving human subjects older than 30years were included in the review, while irrelevant studies (i.e., studies involving subjects with comorbid kidney disease, diabetes and cardiac disease) were excluded from the review. We determined that arterial stiffness severity was positively correlated with cognitive impairment. Of the markers used to assess arterial stiffness, a higher PWV, CAVI, AI, IMT and index-β and a lower ABI and FMD were related to cognitive impairment. However, the relationship between PP and cognitive impairment remained controversial. The potential mechanisms linking arterial stiffness and cognitive impairment may be associated with arterial pulsatility, as greater arterial pulsatility

  6. Temporal distributions, habitat associations and behaviour of the green lizard (Lacerta bilineata and wall lizard (Podarcis muralis on roads in a fragmented landscape in Western France

    Directory of Open Access Journals (Sweden)

    Roger Meek

    2014-12-01

    Full Text Available Observations of the green lizard (Lacerta bilineata and wall lizard (Podarcis muralis on roads in Western France indicated that basking close to the road edge was the predominant activity in L. bilineata but P. muralis mostly foraged. Spatial locations of road mortalities in both species reflected this with the median distances from the road edge greater in P. muralis. Temporal differences in road presence, based on mortality counts and those of live lizards, indicated significantly more lizards were present on roads during late summer and autumn, especially in P. muralis. A significant correlation was found between the monthly presence of live lizards and monthly road mortalities in P. muralis (r = 0.73 but not in L. bilineata (r = 0.64.  Numbers of L. bilineata found on roads bisecting low-density urban areas and roads bordered by hedgerows were higher than expected in relation to the occurrence of these habitats at roadsides. In P. muralis higher than expected numbers were found alongside low-density urban areas and roads bisecting woodland. Generally both species were less commonly seen on roads alongside agricultural areas with no hedgerow border.

  7. Temporal evolution of vasospasm and clinical outcome after intra-arterial vasodilator therapy in patients with aneurysmal subarachnoid hemorrhage.

    Directory of Open Access Journals (Sweden)

    Laleh Daftari Besheli

    Full Text Available Intra-arterial (IA vasodilator therapy is one of the recommended treatments to minimize the impact of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm refractory to standard management. However, its usefulness and efficacy is not well established. We evaluated the effect IA vasodilator therapy on middle cerebral artery blood flow and on discharge outcome. We reviewed records for 115 adults admitted to Neurointensive Care Unit to test whether there was a difference in clinical outcome (discharge mRS in those who received IA infusions. In a subset of 19 patients (33 vessels treated using IA therapy, we tested whether therapy was effective in reversing the trends in blood flow. All measures of MCA blood flow increased from day -2 to -1 before infusion (maximum Peak Systolic Velocity (PSV 232.2±9.4 to 262.4±12.5 cm/s [p = 0.02]; average PSV 202.1±8.5 to 229.9±10.9 [p = 0.02]; highest Mean Flow Velocity (MFV 154.3±8.3 to 172.9±10.5 [p = 0.10]; average MFV 125.5±6.3 to 147.8±9.5 cm/s, [p = 0.02] but not post-infusion (maximum PSV 261.2±14.6 cm/s [p = .89]; average PSV 223.4±11.4 [p = 0.56]; highest MFV 182.9±12.4 cm/s [p = 0.38]; average MFV 153.0±10.2 cm/s [p = 0.54]. After IA therapy, flow velocities were consistently reduced (day X infusion interaction p<0.01 for all measures. However, discharge mRS was higher in IA infusion group, even after adjusting for sex, age, and admission grades. Thus, while IA vasodilator therapy was effective in reversing the vasospasm-mediated deterioration in blood flow, clinical outcomes in the treated group were worse than the untreated group. There is need for a prospective randomized controlled trial to avoid potential confounding effect of selection bias.

  8. Echocardiography-Derived Left Ventricular Outflow Tract Gradient and Left Ventricular Posterior Wall Thickening Are Associated with Outcomes for Anatomic Repair in Congenitally Corrected Transposition of the Great Arteries.

    Science.gov (United States)

    Moodley, Shreya; Balasubramanian, Sowmya; Tacy, Theresa A; Chan, Frandics; Hanley, Frank L; Punn, Rajesh

    2017-08-01

    Congenitally corrected transposition of the great arteries is a rare form of congenital heart disease. Management is controversial; options include observation, physiologic repair, and anatomic repair. Assessment of morphologic left ventricle preparedness is key in timing anatomic repair. This study's purpose was to review the modalities used to assess the morphologic left ventricle preoperatively and to determine if any echocardiographic variables are associated with outcomes. A retrospective review of patients with congenitally corrected transposition of the great arteries eligible for anatomic repair at Lucile Packard Children's Hospital from 2000 to 2016 was conducted. Inclusion criteria were (1) presurgical echocardiography, magnetic resonance imaging, and cardiac catheterization and (2) clinical follow-up information. Echocardiographic measurements included left ventricular (LV) single-plane Simpson's ejection fraction, LV eccentricity index, LV posterior wall thickening, pulmonary artery band (PAB)/LV outflow tract (LVOT) pressure gradient, and LV and right ventricular strain. Magnetic resonance imaging measurements included LV mass, ejection fraction, eccentricity index, and LV thickening. LV pressure, PAB/LVOT gradient, right ventricular pressure, pulmonary vascular resistance, and Qp/Qs constituted catheterization data. Outcomes included achieving anatomic repair within 1 year of assessment in patients with LVOT obstruction or within 1 year of pulmonary artery banding and freedom from death, transplantation, or heart failure at last follow-up. Forty-one patients met the inclusion criteria. PAB/LVOT gradients of 85.2 ± 23.4 versus 64.0 ± 32.1 mm Hg (P = .0282) by echocardiography and 60.1 ± 19.4 versus 35.9 ± 18.9 mm Hg (P = .0030) by catheterization were associated with achieving anatomic repair and freedom from death, transplantation, and heart failure. Echocardiographic LV posterior wall thickening of 35.4 ± 19.8% versus 20.6

  9. Geo-epidemiology of temporal artery biopsy-positive giant cell arteritis in Australia and New Zealand: is there a seasonal influence?

    Science.gov (United States)

    De Smit, Elisabeth; Clarke, Linda; Sanfilippo, Paul G; Merriman, Tony R; Brown, Matthew A; Hill, Catherine L; Hewitt, Alex W

    2017-01-01

    Previous studies, although inconclusive, have suggested possible associations of environmental risk factors with the development of giant cell arteritis (GCA). We aim to investigate seasonal influence on the incidence of GCA across Australia and New Zealand. In establishing an international study to investigate the molecular aetiology of GCA, archived temporal artery biopsy (TAB) specimens primarily from Australia and New Zealand were obtained. Demographic details including age, sex and date of TAB were collected from collaborating pathology departments. The season in which GCA was diagnosed was determined and compared with previous reports investigating the association between environmental risk factors and GCA. Our study comprises data from 2224 TAB-positive patients with GCA; 2099 of which were from patients in Australia and New Zealand. The mean age at time of diagnosis was 76.4 years of age. The female-to-male ratio was 2.2:1. We noted equal distribution of the incidence rate across all four seasons (530-580 cases diagnosed every quarter). Statistical analysis of seasonal variation by Poisson regression and cosinor methods showed no incidence preponderance across seasons. Our results do not support a seasonal component contributing to the onset of disease. Our literature search identifies no consistent environmental risk factor in association with GCA. This is the largest GCA data set reported outside of Europe. Our results demonstrate equal distribution of the incidence rate across all four seasons. In contrast to some earlier reports, we did not identify evidence of a seasonal component contributing to the onset of disease.

  10. Temporal Trends and Geographic Variation of Lower Extremity Amputation in Patients with Peripheral Artery Disease: Results from U.S. Medicare 2000–2008

    Science.gov (United States)

    Jones, W. Schuyler; Patel, Manesh R.; Dai, David; Subherwal, Sumeet; Stafford, Judith; Calhoun, Sarah; Peterson, Eric D.

    2014-01-01

    Objectives We sought to characterize temporal trends, patient-specific factors and geographic variation associated with amputation in patients with lower extremity peripheral artery disease (LE PAD) during the study period. Background Amputation represents the end stage failure for those with LE PAD and little is known about the rates and geographic variation in use of LE amputation. Methods Using data from the Centers for Medicare & Medicaid Services (CMS) from January 1, 2000 to December 31, 2008, we examined national patterns of LE amputation among patients 65 years or older with PAD. Multivariable logistic regression was used to adjust regional results for other patient demographic and clinical factors. Results Among 2,730,742 older patients with identified PAD, the overall rate of LE amputation declined from 7,258 per 100,000 PAD patients to 5,790 per 100,000 (p amputation. The adjusted odds ratio of LE amputation per year between 2000 and 2008 was 0.95 (95% CI, 0.95-0.95, pamputation rates decreased significantly among PAD patients. There however remains significant patient and geographic variation in amputation rates across the United States. PMID:23103040

  11. Correlation between arterial wall stiffness, N-terminal prohormone of brain natriuretic peptide, functional and structural myocardial abnormalities in patients with type 2 diabetes mellitus and cardiac autonomic neuropathy

    Directory of Open Access Journals (Sweden)

    Viktoriya Aleksandrovna Serhiyenko

    2013-12-01

    Full Text Available Aim. To assess arterial wall stiffness, plasma levels of of N-terminal prohormone of brain natriuretic peptide (NT-proBNP, as well as functional state and structure of the myocardium in patients with type 2 diabetes mellitus (T2DM and cardiac autonomic neuropathy (CAN.Materials and Methods. The study involved a total of 65 patients with T2DM. 12 had no evidence of cardiovascular disease (CVD or CAN, 14 were diagnosed with subclinical stage of CAN, 18 – with functional stage, and 21 – with organic stage. We measured aortic pulse wave velocity (PWV, aortic augmentation index (AIx, brachial artery AIx, ambulatory arterial stiffness index (AASI and plasma levels of NT-proBNP. Clinical examination included ECG, Holter monitoring, ambulatory BP measurement and echocardiography.Results. Patients with isolated T2DM showed a trend for increased vascular wall stiffness. PWV was increased in patients with subclinical stage of CAN. Aortic and brachial AIx, PWV and AASI were elevated in patients with functional stage of CAN, PWV being significantly higher vs. subclinical CAN subgroup. Organic stage was characterized by pathologically increased values of all primary parameters; PWV and AASI were significantly higher compared with other groups. Development and progression of CAN was accompanied by an increase in NT-proBNP plasma levels. Concentration of NT-proBNP was in direct correlation with left ventricular mass (LVM and PWV. PWV and LVM values also directly correlated between themselves.Conclusion. Development and progression of CAN in patients with T2DM is accompanied by an increase in vascular wall stiffness. The elevation of plasma NT-proBNP in patients with T2DM correlates with the development of CAN and is significantly and independently associated with an increase in LVM and PWV. Our data suggests the pathophysiological interconnection between metabolic, functional and structural myocardial abnormalities in patients with T2DM and CAN.

  12. Bestrophin-3 associated Ca2+-activated Cl- conductance is important for synchronization in the arterial wall

    DEFF Research Database (Denmark)

    Brøgger, Torbjørn; Aalkjær, Christian; Matchkov, Vladimir

    2009-01-01

    . The efficiency of transfection at molecular level was evaluated 3 days after transfection. Contractility, vasomotion and [Ca2+]i dynamic were tested in isometric myograph and using confocal microscope.   The specific Best-3 siRNA significantly reduced Best-3 expression in comparison to the control. Arteries from...... different groups were similar morphologically and no difference in contractility was seen. The arteries downregulated for Best-3 had significantly reduced amplitude of vasomotion without changes in the frequency. Endothelium denudation abolished vasomotion in both groups. Addition of 8Br......-cGMP to the endothelium-denuded vessels restored vasomotion but did not change the difference between groups. SMCs in control endothelium-intact arteries were completely synchronized whereas in the siRNA-transfected arteries only partial synchronization was observed.   Our data suggest that the Best-3-associated Ic...

  13. Asymptomatic carotid artery stenosis treated with medical therapy alone: temporal trends and implications for risk assessment and the design of future studies.

    Science.gov (United States)

    Hadar, Nira; Raman, Gowri; Moorthy, Denish; O'Donnell, Thomas F; Thaler, David E; Feldmann, Edward; Lau, Joseph; Kitsios, Georgios D; Dahabreh, Issa J

    2014-01-01

    The rate of adverse clinical outcomes among patients with asymptomatic carotid stenosis receiving medical therapy alone can be used to guide clinical decision-making and to inform future research. We aimed to investigate temporal changes in the incidence rate of clinical outcomes among patients with asymptomatic carotid stenosis receiving medical therapy alone and to explore the implications of these changes for the design of future comparative studies. We searched MEDLINE, the Cochrane Central Register of Controlled Trials, US Food and Drug Administration documents, and reference lists of included studies (last search: December 31, 2012). We selected prospective cohort studies of medical therapy for asymptomatic carotid artery stenosis and we extracted information on study characteristics, risk of bias, and outcomes. We performed meta-analyses to estimate summary incidence rates, meta-regressions to assess trends over time, and simulations to explore sample size requirements for the design of future studies comparing new treatments against medical therapy. The main outcomes of interest were ipsilateral stroke, any stroke, cardiovascular death, death, and myocardial infarction. We identified 41 studies of medical therapy for patients with asymptomatic carotid stenosis (last recruitment year: 1978-2009). The summary incidence rate of ipsilateral carotid territory stroke (25 studies) was 1.7 per 100 person-years. This incidence rate was significantly lower in recent studies (last recruitment year from 2000 onwards) as compared to studies that ended recruitment earlier (1.0 vs. 2.3 events per 100 person-years; p studies), cardiovascular death (6 studies), death (13 studies), and myocardial infarction (5 studies) were 2.7, 4.1, 4.6, and 1.8 per 100 person-years, respectively. Simulations showed that future studies would need to enroll large numbers of patients with a relatively high incidence rate under medical therapy, and evaluate interventions with large effect

  14. Asymmetric pulsation of rat carotid artery bifurcation in three-dimension observed by ultrasound imaging.

    Science.gov (United States)

    Jin, Changzhu; Nam, Kweon-Ho; Paeng, Dong-Guk

    2016-10-01

    The arterial structure cyclically fluctuates in three-dimensions (3-D) caused by pulsatile blood flow. The evaluation of arterial wall motion and hemodynamics contributes to early diagnosis of carotid atherosclerosis. Ultrasound is one of the most appropriate imaging modalities to evaluate arterial wall motion in real time. Although many previous studies have discussed the mechanical properties of the carotid artery bifurcation (CAB) from the two-dimensional (2-D) view, the spatio-temporal variation of carotid artery geometry in 3-D has not yet been investigated in detail. In this study, the 3-D data set of CAB from rats was acquired using a high spatio-temporal resolution ultrasound imaging system with a 40 MHz probe using mechanical sector scanning. A total of 31 slices of cross-section images were stored and a spoke scan algorithm was implemented to radially scan the lumen area in polar coordinates based on a pre-tracked seed point. The boundary of the arterial lumen was segmented using intensity-threshold-based boundary detection and fitted by polynomial regression. Two operators, who were trained with the same protocol to minimize inter- and intra-operator variability, manually segmented the lumen boundary on systolic and diastolic phase from the gray-scale images. Finally, the 3-D lumen geometries of CAB during one cardiac cycle were constructed based on the segmented lumen boundaries. From this constructed 3-D geometry, we observed that the CAB geometry favorably expanded to the anterior/posterior direction, parallel to the sagittal plane; and the manually segmented geometry also confirmed the asymmetrical change in bifurcation geometry. This is the first study on visualization and quantification on the asymmetrical variation of the CAB geometry of a rat in 3-D during a whole cardiac cycle. This finding may be useful in understanding hemodynamic etiology of various cardiovascular diseases such as arterial stenosis and its complications, and also provides

  15. The Effect of Spatial and Temporal Resolution of Cine Phase Contrast MRI on Wall Shear Stress and Oscillatory Shear Index Assessment

    NARCIS (Netherlands)

    Cibis, Merih; Potters, Wouter V.; Gijsen, Frank J.; Marquering, Henk; van Ooij, Pim; VanBavel, Ed; Wentzel, Jolanda J.; Nederveen, Aart J.

    2016-01-01

    Introduction Wall shear stress (WSS) and oscillatory shear index (OSI) are associated with atherosclerotic disease. Both parameters are derived from blood velocities, which can be measured with phase-contrast MRI (PC-MRI). Limitations in spatiotemporal resolution of PC-MRI are known to affect these

  16. Multivessel coronary artery thrombosis.

    Science.gov (United States)

    Kanei, Yumiko; Janardhanan, Rajesh; Fox, John T; Gowda, Ramesh M

    2009-02-01

    Simultaneous thrombosis of multiple epicardial coronary arteries is an uncommon clinical finding in ST-segment elevation myocardial infarction (STEMI). We describe a 37-year-old male present with inferior wall STEMI who was found to have large thrombi in both the right coronary artery (RCA) and the left anterior descending artery (LAD). We reviewed 23 patients with multivessel thrombosis in acute myocardial infarction in the literature. The mean age of patients was 53 +/- 14 years (32-82 years); 74% were males, and most patients had multiple risk factors for coronary artery disease. The LAD (78%) and RCA (87%) were the arteries involved for most patients. Aspiration thrombectomy was used in 3 cases. Though it is rare, STEMI with multiple culprit arteries can occur, and it is crucial to recognize this condition to determine the proper treatment, since most of these patients are critically ill.

  17. The Role of Ultrasound Compared to Biopsy of Temporal Arteries in the Diagnosis and Treatment of Giant Cell Arteritis (TABUL): a diagnostic accuracy and cost-effectiveness study.

    Science.gov (United States)

    Luqmani, Raashid; Lee, Ellen; Singh, Surjeet; Gillett, Mike; Schmidt, Wolfgang A; Bradburn, Mike; Dasgupta, Bhaskar; Diamantopoulos, Andreas P; Forrester-Barker, Wulf; Hamilton, William; Masters, Shauna; McDonald, Brendan; McNally, Eugene; Pease, Colin; Piper, Jennifer; Salmon, John; Wailoo, Allan; Wolfe, Konrad; Hutchings, Andrew

    2016-01-01

    BACKGROUND Giant cell arteritis (GCA) is a relatively common form of primary systemic vasculitis, which, if left untreated, can lead to permanent sight loss. We compared ultrasound as an alternative diagnostic test with temporal artery biopsy, which may be negative in 9-61% of true cases. OBJECTIVE To compare the clinical effectiveness and cost-effectiveness of ultrasound with biopsy in diagnosing patients with suspected GCA. DESIGN Prospective multicentre cohort study. SETTING Secondary care. PARTICIPANTS A total of 381 patients referred with newly suspected GCA. MAIN OUTCOME MEASURES Sensitivity, specificity and cost-effectiveness of ultrasound compared with biopsy or ultrasound combined with biopsy for diagnosing GCA and interobserver reliability in interpreting scan or biopsy findings. RESULTS We developed and implemented an ultrasound training programme for diagnosing suspected GCA. We recruited 430 patients with suspected GCA. We analysed 381 patients who underwent both ultrasound and biopsy within 10 days of starting treatment for suspected GCA and who attended a follow-up assessment (median age 71.1 years; 72% female). The sensitivity of biopsy was 39% [95% confidence interval (CI) 33% to 46%], which was significantly lower than previously reported and inferior to ultrasound (54%, 95% CI 48% to 60%); the specificity of biopsy (100%, 95% CI 97% to 100%) was superior to ultrasound (81%, 95% CI 73% to 88%). If we scanned all suspected patients and performed biopsies only on negative cases, sensitivity increased to 65% and specificity was maintained at 81%, reducing the need for biopsies by 43%. Strategies combining clinical judgement (clinician's assessment at 2 weeks) with the tests showed sensitivity and specificity of 91% and 81%, respectively, for biopsy and 93% and 77%, respectively, for ultrasound; cost-effectiveness (incremental net monetary benefit) was £485 per patient in favour of ultrasound with both cost savings and a small health gain. Inter

  18. Arterial responses during migraine headache

    DEFF Research Database (Denmark)

    Iversen, Helle Klingenberg; Nielsen, T H; Olesen, J

    1990-01-01

    The superficial temporal artery has been thought to be the main focus of pain during migraine attacks, but its diameter has never been measured directly. The use of a new, high-resolution ultrasound machine to measure arterial size in 25 migraine patients with unilateral head pain showed...... that the lumen was wider on the painful than on the non-painful side during a migraine attack. The diameters of both radial arteries and the temporal artery on the non-painful side were smaller during than between attacks. The generalised vasoconstriction was not shared by the temporal artery on the affected...... side, which suggests a local vasodilatory response. The findings suggest that cephalic arteries may play a role in migraine pathogenesis....

  19. Monocyte chemoattractant protein 1 (MCP-1) in temporal arteritis and polymyalgia rheumatica

    DEFF Research Database (Denmark)

    Ellingsen, T; Elling, P; Olson, A

    2000-01-01

    OBJECTIVE: To examine the localisation of monocyte chemoattractant protein 1 (MCP-1) in the inflamed vessel wall in temporal arteritis (TA) and to measure MCP-1 in plasma both in patients with TA and patients with polymyalgia rheumatica (PMR). METHODS: By immunohistochemical techniques MCP-1...... was localised to the vessel wall in patients with TA. In TA, PMR, and healthy controls MCP-1 was quantified by enzyme linked immunosorbent assay (ELISA) in plasma. RESULTS: MCP-1 was localised to the majority of mononuclear cells, some smooth muscle cells, and giant cells in the arterial biopsy specimens from...

  20. Vascularização temporária de membros isquêmicos por meio de shunt arteriomedular: trabalho experimental Temporary vascularization on ischemic limbs through arterial-medullar shunt: an experimental work

    Directory of Open Access Journals (Sweden)

    Ronaldo André Poerschke

    2012-03-01

    Full Text Available CONTEXTO: Os autores idealizaram um shunt temporário entre a artéria femoral e o canal medular de ossos longos para manter a viabilidade dos membros agudamente isquêmicos, enquanto não é possível estabelecer um tratamento definitivo. OBJETIVO: Avaliar a perviedade de shunts temporários arteriomedulares e a perfusão dos membros, durante duas horas em cães de experimentação, que tiveram a artéria femoral ligada. MÉTODOS: Alocaram-se aleatoriamente dois grupos, com três cães no Grupo Controle e seis no Grupo Intervenção. Os controles tiveram a artéria femoral comum direita ligada. O Grupo Intervenção, além da ligadura da artéria, recebeu um shunt. Após duas horas, realizou-se a medida de pH dos membros isquêmicos; avaliação do fluxo arterial por meio de um sonar Doppler; avaliação da coloração do sangramento na extremidade distal do membro e foram retirados em bloco torácico os pulmões para análise anatomopatológica. RESULTADOS: A média do pH do sangue capilar das extremidades do membros no Grupo Controle foi de 6,97 (±0,39; no Grupo Intervenção o pH foi de 7,25 (±0,46, com pBACKGROUND: The authors idealized a temporary shunt between the femoral artery and the medullar canal on long bones to keep the viability of acutely ischemic limbs, while waiting for a definitive treatment. OBJECTIVE: To assess the flow on temporary shunts between the femoral artery and the marrow canal of the tibia during two hours in experimental dogs, which had the femoral artery interrupted. METHODS: Two groups with three dogs on the Control Group and six on the Intervention Group were allocated at random. The controls had the right femoral common artery interrupted. The Intervention Group received a shunt between the iliac external artery and the medullar canal of the right tibia in addition. After two hours, the measure of the pH, blood coloration, blood flow in sonar Doppler on the ischemic limbs were performed. The lungs were

  1. Pharmacological modulation of arterial stiffness.

    LENUS (Irish Health Repository)

    Boutouyrie, Pierre

    2011-09-10

    Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for \\'de-stiffening drugs\\

  2. Sex differences in intracranial arterial bifurcations

    DEFF Research Database (Denmark)

    Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K

    2010-01-01

    Subarachnoid hemorrhage (SAH) is a serious condition, occurring more frequently in females than in males. SAH is mainly caused by rupture of an intracranial aneurysm, which is formed by localized dilation of the intracranial arterial vessel wall, usually at the apex of the arterial bifurcation. T....... The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....

  3. Influence of a laminar steady-state fluid-imposed wall shear stress on the binding, internalization, and degradation of low-density lipoproteins by cultured arterial endothelium.

    Science.gov (United States)

    Sprague, E A; Steinbach, B L; Nerem, R M; Schwartz, C J

    1987-09-01

    Fluid mechanical steady-state laminar wall shear stresses of 30 dyne/cm2 (high stress) and less than 1 dyne/cm2 (low stress) have been applied for varying times to confluent cultures of bovine aortic endothelial cells (BAECs) by means of two parallel plate channel flow chambers in series. BAEC cultures not exposed to shear or flow (no stress) were also studied. A shear stress of 30 dyne/cm2 resulted in cellular elongation and alignment, changes that were largely complete by 24 hr. In experiments in which BAECs were incubated with 125I-labeled low-density lipoprotein for 2 or 24 hr in the presence of shear stress levels, 125I-LDL internalization at 24 hr was increased (p less than .05) in response to high-stress conditions. This increased uptake of 125I-LDL was observed in BAECs prealigned for 24 hr under high stress and in BAECs undergoing alignment in the presence of circulating 125I-LDL. BAECs were also exposed to shear stress for 24 hr in the presence of a lipoprotein-deficient circulating medium to maximize LDL receptor expression. Receptor-mediated 125I-LDL internalization and degradation measured immediately after shear stress were both significantly enhanced (p less than .01) in BAECs exposed to high stress. Furthermore, 125I-LDL binding studies at 4 degrees C revealed a significant increase (p less than .01) in specific 125I-LDL binding to BAECs exposed to high stress relative to those exposed to low or no stress. Nonspecific 125I-LDL endocytosis was not influenced by shear stress levels.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Correlations of coronary plaque wall thickness with wall pressure and wall pressure gradient: a representative case study

    Directory of Open Access Journals (Sweden)

    Liu Biyue

    2012-07-01

    Full Text Available Abstract Background There are two major hemodynamic stresses imposed at the blood arterial wall interface by flowing blood: the wall shear stress (WSS acting tangentially to the wall, and the wall pressure (WP acting normally to the wall. The role of flow wall shear stress in atherosclerosis progression has been under intensive investigation, while the impact of blood pressure on plaque progression has been under-studied. Method The correlations of wall thickness (WT with wall pressure (WP, blood pressure on the lumen wall and spatial wall pressure gradient (WPG in a human atherosclerotic right coronary artery were studied. The pulsatile blood flow was simulated using a three dimensional mathematical model. The blood was treated as an incompressible viscous non-Newtonian fluid. The geometry of the artery was re-constructed using an in vivo intravascular ultrasound (IVUS 44-slice dataset obtained from a patient with consent obtained. The WT, the WP and the WPG were averaged on each slice, respectively, and Pearson correlation analysis was performed on slice averaged base. Each slice was then divided into 8 segments and averaged vessel WT, WP and WPG were collected from all 352 segments for correlation analysis. Each slice was also divided into 2 segments (inner semi-wall of bend and outer semi-wall of bend and the correlation analysis was performed on the 88 segments. Results Under mean pressure, the Pearson coefficient for correlation between WT and WP was r = − 0.52 (p  Conclusions Results from this representative case report indicated that plaque wall thickness correlated negatively with wall pressure (r = −0.81 by slice and positively with wall pressure gradient (r = 0.45. The slice averaged WT has a strong linear relationship with the slice averaged WP. Large-scale patient studies are needed to further confirm our findings.

  5. Exposure to Road, Railway, and Aircraft Noise and Arterial Stiffness in the SAPALDIA Study: Annual Average Noise Levels and Temporal Noise Characteristics.

    Science.gov (United States)

    Foraster, Maria; Eze, Ikenna C; Schaffner, Emmanuel; Vienneau, Danielle; Héritier, Harris; Endes, Simon; Rudzik, Franziska; Thiesse, Laurie; Pieren, Reto; Schindler, Christian; Schmidt-Trucksäss, Arno; Brink, Mark; Cajochen, Christian; Marc Wunderli, Jean; Röösli, Martin; Probst-Hensch, Nicole

    2017-09-07

    The impact of different transportation noise sources and noise environments on arterial stiffness remains unknown. We evaluated the association between residential outdoor exposure to annual average road, railway, and aircraft noise levels, total noise intermittency (IR), and total number of noise events (NE) and brachial-ankle pulse wave velocity (baPWV) following a cross-sectional design. We measured baPWV (meters/second) in 2,775 participants (49-81 y old) at the second follow-up (2010-2011) of the Swiss Cohort Study on Air Pollution and Lung and Heart Diseases in Adults (SAPALDIA). We assigned annual average road, railway, and aircraft noise levels (Ldensource), total day- and nighttime NEtime and IRtime (percent fluctuation=0%, none or constant noise; percent fluctuation=100%, high fluctuation) at the most exposed façade using 2011 Swiss noise models. We applied multivariable linear mixed regression models to analyze associations. Medians [interquartile ranges (IQRs)] were baPWV=13.4 (3.1) m/s; Ldenair (57.6% exposed)=32.8 (8.0) dB; Ldenrail (44.6% exposed)=30.0 (8.1) dB; Ldenroad (99.7% exposed): 54.2 (10.6) dB; NEnight=123 (179); NEday=433 (870); IRnight=73% (27); and IRday=63.8% (40.3). We observed a 0.87% (95% CI: 0.31, 1.43%) increase in baPWV per IQR of Ldenrail, which was greater with IRnight>80% or with daytime sleepiness. We observed a nonsignificant positive association between Ldenroad and baPWV in urban areas and a negative tendency in rural areas. NEnight, but not NEday, was associated with baPWV. Associations were independent of the other noise sources and air pollution. Long-term exposure to railway noise, particularly in an intermittent nighttime noise environment, and to nighttime noise events, mainly related to road noise, may affect arterial stiffness, a major determinant of cardiovascular disease. Ascertaining noise exposure characteristics beyond average noise levels may be relevant to better understand noise-related health

  6. Temporal assessment of splenic function in patients who have undergone percutaneous image-guided splenic artery embolization in the setting of trauma.

    Science.gov (United States)

    Pirasteh, Ali; Snyder, Laura L; Lin, Roger; Rosenblum, David; Reed, Steven; Sattar, Abdus; Passalacqua, Matthew; Prologo, J David

    2012-01-01

    The role of transcatheter splenic arterial embolization (SAE) in the nonoperative management of splenic injury is evolving. The purpose of this study is to evaluate patients who have undergone SAE for laboratory markers of hyposplenism in the years after their procedure. Thirty-four subjects who had undergone SAE as part of nonoperative management of splenic trauma during a period of 10 years were included. A blood sample was collected from each patient for complete blood count and smear analysis for peripheral markers of hyposplenism (as indicated by Howell-Jolly bodies [HJBs]). Sample size and power analysis was performed, and likelihoods for various true prevalences were calculated. The average time interval from procedure to follow-up was 4.4 years. No participants had peripheral markers of hyposplenism or abnormalities in cell count on follow-up. Phagocytic function of the spleen in patients who have undergone SAE is preserved, as evidenced by the absence of HJBs on follow-up peripheral blood smears. Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.

  7. Intraoperative Eptifibatide Administration During Urgent Arterial Bypass in Neurosurgery.

    Science.gov (United States)

    Stambolija, Vasilije; Mrak, Goran; Lozic, Marin; Ljevak, Josip; Miklic Bublic, Martina; Scap, Miroslav

    2017-07-01

    In some cases when risk of occlusion of a blood vessel is greater than risk of bleeding when patients undergo urgent or unplanned bypass during neurosurgery, the use of eptifibatide may be an option. We describe 2 patients who underwent arterial bypass in whom eptifibatide was used successfully intraoperatively during neurosurgery for prevention of bypass occlusion. The first patient presented with a right middle cerebral artery (MCA) aneurysm with subocclusive stenosis of the M1 branch. After right-sided osteoplastic frontotemporal craniotomy, the MCA bifurcation was exposed with a bifurcational 6-mm aneurysm with a wide neck. Prebifurcation stenosis was found, with yellow calcification of the vessel wall, and postbifurcation calcification was found on the upper M2 branch. Superficial temporal artery-MCA bypass and occlusion of the MCA aneurysm was done. Before the bypass, continuous intravenous infusion of eptifibatide 1 μg/kg/minute was administered. The patient recovered normally without hemorrhage or neurologic deficit. The second patient presented with a left-sided lateral sphenoid wing meningioma. Left-sided frontotemporal craniotomy was performed, and the tumor was completely removed from the arachnoid layer. The temporal M3 branch was invaded by the meningioma. As there was no flow through the invaded segment of the aforementioned artery, termino-terminal M3 arterial anastomosis was done. Continuous intravenous infusion of eptifibatide 1 μg/kg/minute was administered. Indocyanine green angiography showed normal flow through the anastomosis, and the patient recovered normally. Future studies are needed to test the safety and potential efficacy of eptifibatide in intraoperative settings. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. The extended abdominal wall flap for transplantation.

    Science.gov (United States)

    Hollenbeck, S T; Senghaas, A; Turley, R; Ravindra, K V; Zenn, M R; Levin, L S; Erdmann, D

    2011-06-01

    Patients with extensive loss of the abdominal wall tissue have few options for restoring the abdominal cavity. Composite tissue allotransplantation has been used for limited abdominal wall reconstruction in the setting of visceral transplantation, yet replacement of the entire abdominal wall has not been described. The purpose of this study was to determine the maximal abdominal skin surface available through an external iliac/femoral cuff-based pedicle. Five human cadaveric abdominal walls were injected with methylene blue to analyze skin perfusion based on either the deep inferior epigastric artery (DIEA; n = 5) or a cuff of external iliac/femoral artery (n = 5) containing the deep circumflex iliac, deep inferior epigastric, and superficial inferior epigastric, and superficial circumflex iliac arteries. Abdominal wall flaps were taken full thickness from the costal margin to the midaxillary line and down to the pubic tubercle and proximal thigh. In all specimens, the deep inferior epigastric, deep circumflex iliac, superficial inferior epigastric, and superficial circumflex iliac arteries were found to originate within a 4-cm cuff of the external iliac/femoral artery. Abdominal wall flaps injected through a unilateral external iliac/femoral segment had a significantly greater degree of total flap perfusion than those injected through the DIEA alone (76.5% ± 4% vs 57.2% ± 5%; Student t test, P DIEA vessel alone. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. A multiscale SPH particle model of the near-wall dynamics of leukocytes in flow.

    Science.gov (United States)

    Gholami, Babak; Comerford, Andrew; Ellero, Marco

    2014-01-01

    A novel multiscale Lagrangian particle solver based on SPH is developed with the intended application of leukocyte transport in large arteries. In such arteries, the transport of leukocytes and red blood cells can be divided into two distinct regions: the bulk flow and the near-wall region. In the bulk flow, the transport can be modeled on a continuum basis as the transport of passive scalar concentrations. Whereas in the near-wall region, specific particle tracking of the leukocytes is required and lubrication forces need to be separately taken into account. Because of large separation of spatio-temporal scales involved in the problem, simulations of red blood cells and leukocytes are handled separately. In order to take the exchange of leukocytes between the bulk fluid and the near-wall region into account, solutions are communicated through coupling of conserved quantities at the interface between these regions. Because the particle tracking is limited to those leukocytes lying in the near-wall region only, our approach brings considerable speedup to the simulation of leukocyte circulation in a test geometry of a backward-facing step, which encompasses many flow features observed in vivo. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Mechanical instability of normal and aneurysmal arteries.

    Science.gov (United States)

    Lee, Avione Y; Sanyal, Arnav; Xiao, Yangming; Shadfan, Ramsey; Han, Hai-Chao

    2014-12-18

    Tortuous arteries associated with aneurysms have been observed in aged patients with atherosclerosis and hypertension. However, the underlying mechanism is poorly understood. The objective of this study was to determine the effect of aneurysms on arterial buckling instability and the effect of buckling on aneurysm wall stress. We investigated the mechanical buckling and post-buckling behavior of normal and aneurysmal carotid arteries and aorta's using computational simulations and experimental measurements to elucidate the interrelationship between artery buckling and aneurysms. Buckling tests were done in porcine carotid arteries with small aneurysms created using elastase treatment. Parametric studies were done for model aneurysms with orthotropic nonlinear elastic walls using finite element simulations. Our results demonstrated that arteries buckled at a critical buckling pressure and the post-buckling deflection increased nonlinearly with increasing pressure. The presence of an aneurysm can reduce the critical buckling pressure of arteries, although the effect depends on the aneurysm's dimensions. Buckled aneurysms demonstrated a higher peak wall stress compared to unbuckled aneurysms under the same lumen pressure. We conclude that aneurysmal arteries are vulnerable to mechanical buckling and mechanical buckling could lead to high stresses in the aneurysm wall. Buckling could be a possible mechanism for the development of tortuous aneurysmal arteries such as in the Loeys-Dietz syndrome. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Habitual exercise and arterial aging

    OpenAIRE

    Seals, Douglas R.; DeSouza, Christopher A.; Donato, Anthony J.; Tanaka, Hirofumi

    2008-01-01

    Aging affects the function and structure of arteries and increases the risk of cardiovascular diseases (CVD). In healthy sedentary adults, aging is associated with increased stiffness (reduced compliance) of large elastic arteries; impaired vascular endothelial function, including reductions in endothelium-dependent dilation (EDD), release of tissue-type plasminogen activator (fibrinolytic capacity) and endothelial progenitor cell number and function; increased intima-media wall thickness (IM...

  12. Obesity and carotid artery remodeling

    DEFF Research Database (Denmark)

    Kozakova, M; Palombo, C; Morizzo, C

    2015-01-01

    characterized by body size-dependent increase in stroke volume (SV) and blood pressure (BP). SUBJECTS/METHODS: Common carotid artery (CCA) luminal diameter (LD), IMT and CWS were measured in three different populations in order to study: (A) cross-sectional associations between SV, BP, anthropometric parameters...... the luminal enlargement caused by body size-induced increase in SV, and therefore, to normalize the wall stress. CCA diameter in obesity could represent an additional biomarker, depicting the impact of altered hemodynamics on arterial wall....

  13. Ambiguous walls

    DEFF Research Database (Denmark)

    Mody, Astrid

    2012-01-01

    of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...... and flat, “ambiguous walls” combine softness, tectonics and three-dimensionality. The paper considers a selection of luminious surfaces and reflects on the extent of their ambiguous qualities. Initial ideas for new directions for the wall will be essayed through the discussion....

  14. Anomalous Origin of the Left Coronary Artery From the Pulmonary Artery

    Directory of Open Access Journals (Sweden)

    Venkat Gangadharan MD

    2017-01-01

    Full Text Available A 36-year-old woman was seen with complaints of exertional chest pain and shortness of breath. Her medical history included atrial fibrillation and diabetes. Physical examination was unremarkable except for an irregular cardiac rhythm. Myocardial perfusion imaging revealed the presence of a large area of infarction involving the entire anterior and apical walls and part of the anteroseptal wall with minimal periinfarct ischemia. Computed tomography coronary angiogram revealed an anomalous left main coronary artery arising from the main pulmonary artery. Right and left heart catheterizations demonstrated moderate pulmonary hypertension with a slight step-up in oxygen saturation between the right ventricle and main pulmonary artery. Coronary angiography showed a large tortuous right coronary artery with collaterals to the left anterior descending artery that drained into the main pulmonary artery. She was referred for surgery. This case demonstrates a rare coronary artery anomaly in an adult where survival is dependent on collateral circulation.

  15. Increased arterial compliance in decompensated cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Møller, Søren; Schifter, S

    1999-01-01

    of CGRP (r=0.34, pinverse correlation was present to MAP (r= -0.63, pinversely related...... to the level of arterial blood pressure. The altered static and dynamic functions of the arterial wall in cirrhosis may have implications for the circulatory and homoeostatic derangement, and potentially for therapy with vasoactive drugs....

  16. Analysis of rheological properties of Herschel-Bulkley fluid for pulsating flow of blood in ω-shaped stenosed artery

    Science.gov (United States)

    Abbas, Z.; Shabbir, M. S.; Ali, N.

    2017-10-01

    In the present article, we examined the pulsating flow of blood in the tapered ω-shaped stenosed arterial segment. The Herschel-Bulkley fluid model is used to represent the non-Newtonian characteristics of blood in narrow arteries. The equation governing the present flow is modelled by assuming that the flow is unsteady and one dimensional. Regular perturbation method is used to find the first order expression of various flow variables. The temporal and axial distributions of velocity, wall shear stress, volumetric flux and resistance to the flow are displayed graphically. The effects of various involved parameters on the radius of plug flow region are also discussed. A comparison between the flow of blood in single symmetric and ω-shaped stenotic regions of the arteries is also analyzed.

  17. Anatomical variation of arterial supply to the rabbit stomach.

    Science.gov (United States)

    Ikegami, Reona; Tanimoto, Yoshimasa; Kishimoto, Miori; Shibata, Hideshi

    2016-05-03

    Gastric stasis is common in rabbits, and gastrotomy may be performed to cure this pathological condition. Detailed descriptions of the arterial supply to the stomach are essential for this surgical operation, but published descriptions are limited. Here, we investigated anatomical variations of the arterial supply to the stomach in 43 New Zealand White rabbits by injecting colored latex into arteries. We observed that the left gastric artery that arose as the second branch from the celiac artery provided 1-3 parietal and 1-3 visceral branches to the stomach, with various branching patterns depending on the case. In 34 of 43 cases, the left gastric artery ended upon entering the gastric wall at the lesser curvature, whereas in the remaining cases, the artery continued as the hepatic artery without entering the gastric wall. The right gastric artery that branched off from the gastroduodenal artery also supplied the lesser curvature sinistrally but did not anastomose with the left gastric artery. In 40 cases, the hepatic artery provided 1-4 pyloric branches. In the fundic region, the short gastric arteries arose from the splenic artery and varied in number from 2 to 6. The right and left gastroepiploic arteries anastomosed to give 2-7 branches to the greater curvature. The results showed that many variations occurred in the arteries supplying the rabbit stomach, suggesting that such variations should be considered when performing veterinary surgical treatments in rabbits.

  18. Intravascular ultrasound for iliac artery imaging. Clinical review

    DEFF Research Database (Denmark)

    Vogt, K G; Schroeder, T V

    2001-01-01

    IVUS is able to produce trans-sectional images of the iliac arteries at a high resolution. The three layered appearance of the arterial wall can be visualized. In the atherosclerotic diseased artery calcified plaques can be discerned from non-calcified plaques, and the distribution of the plaque...

  19. In vivo serial MR imaging of magnetically labeled endothelial progenitor cells homing to the endothelium injured artery in mice.

    Directory of Open Access Journals (Sweden)

    Jun Chen

    Full Text Available BACKGROUND: Emerging evidence of histopathological analyses suggests that endothelial progenitor cells (EPCs play an important role in vascular diseases. Neointimal hyperplasia can be reduced by intravenous transfusion of EPCs after vascular injury in mice. Therefore, it would be advantageous to develop an in vivo technique that can explore the temporal and spatial migration of EPCs homing to the damaged endothelium noninvasively. METHODOLOGY/PRINCIPAL FINDINGS: The left carotid common artery (LCCA was injured by removal of endothelium with a flexible wire in Kunming mice. EPCs were collected by in vitro culture of spleen-derived mouse mononuclear cells (MNCs. EPCs labeling was carried out in vitro using Fe₂O₃-poly-L-lysine (Fe₂O₃-PLL. In vivo serial MR imaging was performed to follow-up the injured artery at different time points after intravenous transfusion of EPCs. Vessel wall areas of injured artery were computed on T₂WI. Larger MR signal voids of vessel wall on T₂WI was revealed in all 6 mice of the labeled EPC transfusion group 15 days after LCCA injury, and it was found only in 1 mouse in the unlabeled EPC transfusion group (p = 0.015. Quantitative analyses of vessel wall areas on T₂WI showed that the vessel wall areas of labeled EPC transfusion group were less than those of unlabeled EPC transfusion group and control group fifteen days after artery injury (p<0.05. Histopathological analyses confirmed accumulation and distribution of transfused EPCs at the injury site of LCCA. CONCLUSIONS/SIGNIFICANCE: These data indicate that MR imaging might be used as an in vivo method for the tracking of EPCs homing to the endothelium injured artery.

  20. Haemodynamic assessment of human coronary arteries is affected by degree of freedom of artery movement.

    Science.gov (United States)

    Javadzadegan, Ashkan; Yong, Andy S C; Chang, Michael; Ng, Martin K C; Behnia, Masud; Kritharides, Leonard

    2017-02-01

    Abnormal haemodynamic parameters are associated with atheroma plaque progression and instability in coronary arteries. Flow recirculation, shear stress and pressure gradient are understood to be important pathogenic mediators in coronary disease. The effect of freedom of coronary artery movement on these parameters is still unknown. Fluid-structure interaction (FSI) simulations were carried out in 25 coronary artery models derived from authentic human coronaries in order to investigate the effect of degree of freedom of movement of the coronary arteries on flow recirculation, wall shear stress (WSS) and wall pressure gradient (WPG). Each FSI model had distinctive supports placed upon it. The quantitative and qualitative differences in flow recirculation, maximum wall shear stress (MWSS), areas of low wall shear stress (ALWSS) and maximum wall pressure gradient (MWPG) for each model were determined. The results showed that greater freedom of movement was associated with lower MWSS, smaller ALWSS, smaller flow recirculation zones and lower MWPG. With increasing percentage diameter stenosis (%DS), the effect of degree of freedom on flow recirculation and WSS diminished. Freedom of movement is an important variable to be considered for computational modelling of human coronary arteries, especially in the setting of mild to moderate stenosis. 3D: Three-dimensional; 3DR: Three-dimensional Reconstruction; 3D-QCA: Three-dimensional quantitative coronary angiography; ALWSS: Areas of low wall shear stress; CAD: Coronary artery disease; CFD: Computational fluid dynamics; %DS: Diameter stenosis percentage; EPCS: End point of counter-rotating streamlines; FSI: Fluid-structure interaction; IVUS: Intravascular ultrasound; LAD: Left anterior descending; MWSS: Maximum wall shear stress; SST: Shear stress transport; TAWSS: Time-averaged wall shear stress; WSS: wall shear stress; WPG: Wall pressure gradient; MWPG: Maximum wall pressure gradient; FFR: Fractional flow reserve; i

  1. Wall Art

    Science.gov (United States)

    McGinley, Connie Q.

    2004-01-01

    The author of this article, an art teacher at Monarch High School in Louisville, Colorado, describes how her experience teaching in a new school presented an exciting visual challenge for an art teacher--monotonous brick walls just waiting for decoration. This school experienced only minimal instances of graffiti, but as an art teacher, she did…

  2. Impact of age, sex and exercise on brachial and popliteal artery remodelling in humans.

    NARCIS (Netherlands)

    Green, D.J.; Swart, A.; Exterkate, A.; Naylor, L.H.; Black, M.A.; Cable, N.T.; Thijssen, D.H.J.

    2010-01-01

    OBJECTIVE: To examine the impact of age, sex and exercise on wall thickness and remodelling in the popliteal and brachial arteries. METHODS: We compared wall thickness, lumen diameter and wall:lumen ratios in the brachial and popliteal arteries of 15 young (Y, 25.4+/-0.8 yr; 7M 8W) and 16 older

  3. Assessment of conduit artery vasomotion using photoplethysmography

    Science.gov (United States)

    Kanders, Karlis; Grabovskis, Andris; Marcinkevics, Zbignevs; Aivars, Juris Imants

    2013-11-01

    Vasomotion is a spontaneous oscillation of vascular tone. The phenomenon has been observed in small arterioles and capillaries as well as in the large conduit arteries. The layer of smooth muscle cells that surrounds a blood vessel can spontaneously and periodically change its tension and thereby the arterial wall stiffness also changes. As the understanding of the phenomenon is still rather obscure, researchers would benefit from a low-cost and reliable investigation technique such as photoplethysmography (PPG). PPG is an optical blood pulsation measurement technique that can offer substantial information about the arterial stiffness. The aims of this pilot study were to evaluate the usefulness of the PPG technique in the research of vasomotion and to investigate vasomotion in the relatively large conduit arteries. Continuous 15 minute long measurements of posterior tibial artery wall stiffness were taken. Artery diameter, electrocardiogram, blood pressure and respiration were also simultaneously registered. Fast Fourier Transform power spectra were calculated to identify unique stiffness oscillations that did not correspond to fluctuations in the systemic parameters and thus would indicate vasomotion. We concluded that photoplethysmography is a convenient method for the research of the vasomotion in large arteries. Local stiffness parameter b/a is more accurate to use and easier to measure than the pulse wave velocity which describes stiffness of a segment of an artery. Conduit arteries might exhibit a low amplitude high frequency vasomotion ( 9 to 27 cycles per minute). Low frequency vasomotion is problematic to distinguish from the passive oscillations imposed by the arterial pressure.

  4. [Sports-related carotid artery dissection].

    Science.gov (United States)

    Berrouschot, J; Bormann, A; Routsi, D; Stoll, A

    2009-09-01

    Sports-related carotid artery dissection are very rare and were described in different kinds of sports. We report on a 45-year old man who suffered bilateral brain infarctions caused by bilateral extracranial internal carotid artery dissection after excessive weight lifting in a gym. As possible trigger factors for the dissections we assumed the abrupt extension of the neck during weight lifting and the frequent Valsalva manoeuvers with massive rise in the pressure in the carotid artery system. The patient underwent angioplasty and stenting of the stenosis of right carotid artery, the primarily occluded left carotid artery recanalized spontaneously. Secondary prevention was established by platelet aggregation inhibitors. The patient recovered completely. The pathogenesis of sports-related dissections is multifactorial. In addition to sporting activities hereditary or acquired structural aberrations in the arterial walls could be discussed. Acute focal neurological symptoms after sport should always focus on carotid or vertebral artery dissection. (c) Georg Thieme Verlag KG Stuttgart-New York.

  5. Arterial endothelial function measurement method and apparatus

    Science.gov (United States)

    Maltz, Jonathan S; Budinger, Thomas F

    2014-03-04

    A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

  6. Arteriosclerotic femoral artery aneurysms. A short review

    DEFF Research Database (Denmark)

    Levi, N; Schroeder, T V

    1997-01-01

    True arteriosclerotic aneurysms of the femoral artery are rare but they are dangerous lesions that may thrombose, embolise or rupture. They are often bilateral and frequently the patient has other aneurysms in the abdominal aortic or popliteal artery. True femoral aneurysms were originally...... classified by Cutler and Darling in 1973 as type 1 and type 2 according to their relationship to the common femoral bifurcation. Case reports of isolated superficial and profunda femoral artery aneurysms have been published, but these are exceedingly rare although isolated aneurysms of the profunda femoris...... artery may be more common in Denmark. True femoral artery aneurysms are attributed to weakening of the arterial wall due to atherosclerosis. True femoral artery aneurysms are relatively rare and are found in elderly smoking men. Aortic aneurysms are approximately 10 times more common. Distal embolization...

  7. Low prevalence of significant carotid artery disease in Iranian patients undergoing elective coronary artery bypass

    Directory of Open Access Journals (Sweden)

    Karimi Fatemeh

    2007-01-01

    Full Text Available Abstract Background Coronary artery bypass grafting ranks as one of the most frequent operations worldwide. The presence of carotid artery stenosis may increase the stroke rate in the perioperative period. Routine preoperative noninvasive assessment of the carotid arteries are recommended in many institutions to reduce the stroke rate. Methods 271 consecutive patients undergoing coronary artery bypass grafting at Shaheed Madani hospital of Tabriz, Iran (age, 58.5 Y; 73.1% male underwent preoperative ultrasonography for assessment of carotid artery wall thickness. Results Plaque in right common, left common, right internal and left internal carotid arteries was detected in 4.8%, 7.4%, 43.2% and 42.1% of patients respectively. 5 patients (1.8% had significant ( Conclusion Consecutive Iranian patients undergoing elective coronary artery bypass surgery show a very low prevalence of significant carotid artery disease.

  8. Wall Layers

    Science.gov (United States)

    1992-01-14

    Sydney, Australia. December 6, 1990. Lumley, J. L. A dynamical-systems-theory approach to the wall region. Environmental Engineering Laboratory, CSIRO...Nonlinear Science. Holmes, P. Editor in Chief, Nonlinear Scinece Today. Holmes, P. Reviewer for Physica D, J. Sound Vib., J. Phys., Q. Appl. Math, Phys...Spring, 1994; Organizing committee member. Holmes, P. Editorial Board Member: Archive for Rational Mechanics and Analysis; Journal of Nonlinear Scinece

  9. CLIMBING WALL

    CERN Multimedia

    1999-01-01

    The FIRE AND RESCUE Group of TIS Commission informs that the climbing wall in the yard of the Fire-fighters Station, is intended for the sole use of the members of that service, and recalls that access to this installation is forbidden for safety reasons to all persons not belonging to the Service.CERN accepts no liability for damage or injury suffered as a result of failure to comply with this interdiction.TIS/DI

  10. Transcatheter arterial embolization of a pseudoaneurysm of gastroduodenal artery: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Han, Young Min; Kang, Sung Soo; Lee, Jeong Min; Chung, Jin Young; Lee, Sang Yong; Chung, Gyung Ho; Kim, Chong Soo; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University School of Medicine, Chonju (Korea, Republic of)

    1997-01-01

    Gastroduodenal artery pseudoaneurysm is a relatively rare and potentionally life-threatening complication of chronic pancreatitis, which is thought to occur because of autodigestion of arterial walls by pancreatic enzymes. Embolotherapy should probably be the first method of treatment, since surgical treatment carries a high risk of mortality and morbidity. We report the case of 30-year-old male with gastroduodenal artery pseudoaneurysm caused by chronic pancreatitis which was successfully treated by transcatheter embolization using Gianturco spring coils.

  11. Pulsatile flow in a coronary artery using multiphase kinetic theory.

    Science.gov (United States)

    Huang, Jing; Lyczkowski, Robert W; Gidaspow, Dimitri

    2009-04-16

    Pulsatile flow in a model of a right coronary artery (RCA) was previously modeled as a single-phase fluid and as a two-phase fluid using experimental rheological data for blood as a function of hematocrit and shear rate. Here we present a multiphase kinetic theory model which has been shown to compute correctly the viscosity of red blood cells (RBCs) and their migration away from vessel walls: the Fahraeus-Lindqvist effect. The computed RBC viscosity decreases with shear rate and vessel size, consistent with measurements. The pulsatile computations were performed using a typical cardiac waveform until a limit cycle was well established. The RBC volume fractions, shear stresses, shear stress gradients, granular temperatures, viscosities, and phase velocities varied with time and position during each cardiac cycle. Steady-state computations were also performed and were found to compare well with time-averaged transient results. The wall shear stress and wall shear stress gradients (both spatial and temporal) were found to be highest on the inside area of maximum curvature. Potential atherosclerosis sites are identified using these computational results.

  12. The contribution of arterial calcification to peripheral arterial disease in pseudoxanthoma elasticum.

    Directory of Open Access Journals (Sweden)

    Georges Leftheriotis

    Full Text Available The contribution of arterial calcification (AC in peripheral arterial disease (PAD and arterial wall compressibility is a matter of debate. Pseudoxanthoma elasticum (PXE, an inherited metabolic disease due to ABCC6 gene mutations, combines elastic fiber fragmentation and calcification in various soft tissues including the arterial wall. Since AC is associated with PAD, a frequent complication of PXE, we sought to determine the role of AC in PAD and arterial wall compressibility in this group of patients.Arterial compressibility and patency were determined by ankle-brachial pressure index (ABI in a cohort of 71 PXE patients (mean age 48 ± SD 14 yrs, 45 women and compared to 30 controls without PAD. Lower limb arterial calcification (LLAC was determined by non-contrast enhanced helicoidal CT-scan. A calcification score (Ca-score was computed for the femoral, popliteal and sub-popliteal artery segments of both legs. Forty patients with PXE had an ABI1.40. LLAC increased with age, significantly more in PXE subjects than controls. A negative association was found between LLAC and ABI (r = -0.363, p = 0.002. The LLAC was independently associated with PXE and age, and ABI was not linked to cardiovascular risk factors.The presence of AC was associated with PAD and PXE without affecting arterial compressibility. PAD in PXE patients is probably due to proximal obstructive lesions developing independently from cardiovascular risk factors.

  13. The contribution of arterial calcification to peripheral arterial disease in pseudoxanthoma elasticum.

    Science.gov (United States)

    Leftheriotis, Georges; Kauffenstein, Gilles; Hamel, Jean François; Abraham, Pierre; Le Saux, Olivier; Willoteaux, Serge; Henrion, Daniel; Martin, Ludovic

    2014-01-01

    The contribution of arterial calcification (AC) in peripheral arterial disease (PAD) and arterial wall compressibility is a matter of debate. Pseudoxanthoma elasticum (PXE), an inherited metabolic disease due to ABCC6 gene mutations, combines elastic fiber fragmentation and calcification in various soft tissues including the arterial wall. Since AC is associated with PAD, a frequent complication of PXE, we sought to determine the role of AC in PAD and arterial wall compressibility in this group of patients. Arterial compressibility and patency were determined by ankle-brachial pressure index (ABI) in a cohort of 71 PXE patients (mean age 48 ± SD 14 yrs, 45 women) and compared to 30 controls without PAD. Lower limb arterial calcification (LLAC) was determined by non-contrast enhanced helicoidal CT-scan. A calcification score (Ca-score) was computed for the femoral, popliteal and sub-popliteal artery segments of both legs. Forty patients with PXE had an ABI1.40. LLAC increased with age, significantly more in PXE subjects than controls. A negative association was found between LLAC and ABI (r = -0.363, p = 0.002). The LLAC was independently associated with PXE and age, and ABI was not linked to cardiovascular risk factors. The presence of AC was associated with PAD and PXE without affecting arterial compressibility. PAD in PXE patients is probably due to proximal obstructive lesions developing independently from cardiovascular risk factors.

  14. Habitual exercise and arterial aging.

    Science.gov (United States)

    Seals, Douglas R; Desouza, Christopher A; Donato, Anthony J; Tanaka, Hirofumi

    2008-10-01

    Aging affects the function and structure of arteries and increases the risk of cardiovascular diseases (CVD). In healthy sedentary adults, aging is associated with increased stiffness (reduced compliance) of large elastic arteries; impaired vascular endothelial function, including reductions in endothelium-dependent dilation (EDD), release of tissue-type plasminogen activator (fibrinolytic capacity) and endothelial progenitor cell number and function; increased intima-media wall thickness (IMT); and peripheral vasoconstriction (decreased basal leg blood flow). Habitual physical activity/increased aerobic exercise capacity is associated with reduced risk of CVD. Compared with their sedentary peers, adults who regularly perform aerobic exercise demonstrate smaller or no age-associated increases in large elastic artery stiffness, reductions in vascular endothelial function, and increases in femoral artery IMT. A short-term, moderate-intensity aerobic exercise intervention (brisk daily walking for 12 wk) improves carotid artery compliance and can restore vascular endothelial function in previously sedentary middle-aged and older adults. Reduced oxidative stress may be an important mechanism contributing to these effects. Habitual resistance exercise increases (high-intensity) or does not affect (moderate-intensity) large elastic artery stiffness, and prevents/restores the age-associated reduction in basal leg blood flow independent of changes in leg fat-free mass. Habitual exercise favorably modulates several expressions of arterial aging, thus preserving vascular function and possibly reducing the risk of CVD.

  15. Coronary Artery Bypass Grafting

    Science.gov (United States)

    ... Health Topics / Coronary Artery Bypass Grafting Coronary Artery Bypass Grafting What Is Coronary artery bypass grafting (CABG) ... multiple coronary arteries during one surgery. Coronary Artery Bypass Grafting Figure A shows the location of the ...

  16. Coronary artery anatomy and variants.

    Science.gov (United States)

    Malagò, Roberto; Pezzato, Andrea; Barbiani, Camilla; Alfonsi, Ugolino; Nicolì, Lisa; Caliari, Giuliana; Pozzi Mucelli, Roberto

    2011-12-01

    Variants and congenital anomalies of the coronary arteries are usually asymptomatic, but may present with severe chest pain or cardiac arrest. The introduction of multidetector CT coronary angiography (MDCT-CA) allows the detection of significant coronary artery stenosis. Improved performance with isotropic spatial resolution and higher temporal resolution provides a valid alternative to conventional coronary angiography (CCA) in many patients. MDCT-CA is now considered the ideal tool for three-dimensional visualization of the complex and tortuous anatomy of the coronary arteries. With multiplanar and volume-rendered reconstructions, MDCT-CA may even outperform CCA in determining the relative position of vessels, thus providing a better view of the coronary vascular anatomy. The purpose of this review is to describe the normal anatomy of the coronary arteries and their main variants based on MDCT-CA with appropriate reconstructions.

  17. Coronary artery anatomy and variants

    Energy Technology Data Exchange (ETDEWEB)

    Malago, Roberto; Pezzato, Andrea; Barbiani, Camilla; Alfonsi, Ugolino; Nicoli, Lisa; Caliari, Giuliana; Pozzi Mucelli, Roberto [Policlinico G.B. Rossi, University of Verona, Department of Radiology, Verona (Italy)

    2011-12-15

    Variants and congenital anomalies of the coronary arteries are usually asymptomatic, but may present with severe chest pain or cardiac arrest. The introduction of multidetector CT coronary angiography (MDCT-CA) allows the detection of significant coronary artery stenosis. Improved performance with isotropic spatial resolution and higher temporal resolution provides a valid alternative to conventional coronary angiography (CCA) in many patients. MDCT-CA is now considered the ideal tool for three-dimensional visualization of the complex and tortuous anatomy of the coronary arteries. With multiplanar and volume-rendered reconstructions, MDCT-CA may even outperform CCA in determining the relative position of vessels, thus providing a better view of the coronary vascular anatomy. The purpose of this review is to describe the normal anatomy of the coronary arteries and their main variants based on MDCT-CA with appropriate reconstructions. (orig.)

  18. Coronary Arteries

    Science.gov (United States)

    ... animations for grades K-6. The Coronary Arteries Coronary Circulation The heart muscle, like every other organ or ... the heart by its own vascular system, called coronary circulation. The aorta (the main blood supplier to the ...

  19. Non-Newtonian blood flow dynamics in a right internal carotid artery with a saccular aneurysm

    Science.gov (United States)

    Valencia, Alvaro; Zarate, Alvaro; Galvez, Marcelo; Badilla, Lautaro

    2006-02-01

    Flow dynamics plays an important role in the pathogenesis and treatment of cerebral aneurysms. The temporal and spatial variations of wall shear stress in the aneurysm are hypothesized to be correlated with its growth and rupture. In addition, the assessment of the velocity field in the aneurysm dome and neck is important for the correct placement of endovascular coils. This work describes the flow dynamics in a patient-specific model of carotid artery with a saccular aneurysm under Newtonian and non-Newtonian fluid assumptions. The model was obtained from three-dimensional rotational angiography image data and blood flow dynamics was studied under physiologically representative waveform of inflow. The three-dimensional continuity and momentum equations for incompressible and unsteady laminar flow were solved with a commercial software using non-structured fine grid with 283 115 tetrahedral elements. The intra-aneurysmal flow shows complex vortex structure that change during one pulsatile cycle. The effect of the non-Newtonian properties of blood on the wall shear stress was important only in the arterial regions with high velocity gradients, on the aneurysmal wall the predictions with the Newtonian and non-Newtonian blood models were similar.

  20. Caroli's syndrome leading to splenic artery aneurysm: a rare presentation.

    Science.gov (United States)

    Mandal, Shramana; Das, Partha M; Mandal, A K

    2009-02-01

    Splenic artery aneurysm is a rare disorder (0.7%) that arises mainly as a sequlae to portal hypertension. Other causes of splenic artery aneurysm are atherosclerosis, arterial wall injury due to trauma, pancreatitis, and medial dysplasias of the wall. However, though Caroli's disease is known to cause portal hypertension, the rise of vascular pressure leading to aneurysm is not yet reported (extensive Medlar search failed to reveal any publication). Every effort should be made to diagnose this condition as early as possible because 25% of ruptured splenic aneurysms are fatal. A unique case of Caroli's disease giving rise to splenic artery aneurysm and its possible pathogenesis is reported.

  1. [Arterial rigidity in patients with chronic obstructive pulmonary disease].

    Science.gov (United States)

    Karoli, N A; Dolishniaia, G R; Rebrov, A P

    2012-01-01

    The aim of this open study was to estimate arterial rigidity in patients with chronic obstructive pulmonary disease (COPD). It included 105 patients above 40 years of age. Exclusion criteria were clinical signs of CHD, peripheral atherosclerosis, and other severe chronic diseases in the exacerbation phase. The control group was comprised of 27 practically healthy volunteers. The arterial fluid was detected using a Tensioclinic arteriograph (Tensiomed, Hungary). Arterial rigidity was estimated in patients of two age groups (below and above 60 years) with COPD of different severity The results suggest the development of arterial wall lesions in proportion to the patients' age and COPD severity. It was shown that excessive arterial rigidity and accelerated pulse wave reflection (increased speed of pulse wave propagation and augmentation index) exert significant influence on the elevation of central arterial pressure. Enhanced rigidity of the arterial wall being a cardiovascular risk factor further prospective studies are needed.

  2. Understanding the fluid mechanics behind transverse wall shear stress.

    Science.gov (United States)

    Mohamied, Yumnah; Sherwin, Spencer J; Weinberg, Peter D

    2017-01-04

    The patchy distribution of atherosclerosis within arteries is widely attributed to local variation in haemodynamic wall shear stress (WSS). A recently-introduced metric, the transverse wall shear stress (transWSS), which is the average over the cardiac cycle of WSS components perpendicular to the temporal mean WSS vector, correlates particularly well with the pattern of lesions around aortic branch ostia. Here we use numerical methods to investigate the nature of the arterial flows captured by transWSS and the sensitivity of transWSS to inflow waveform and aortic geometry. TransWSS developed chiefly in the acceleration, peak systolic and deceleration phases of the cardiac cycle; the reverse flow phase was too short, and WSS in diastole was too low, for these periods to have a significant influence. Most of the spatial variation in transWSS arose from variation in the angle by which instantaneous WSS vectors deviated from the mean WSS vector rather than from variation in the magnitude of the vectors. The pattern of transWSS was insensitive to inflow waveform; only unphysiologically high Womersley numbers produced substantial changes. However, transWSS was sensitive to changes in geometry. The curvature of the arch and proximal descending aorta were responsible for the principal features, the non-planar nature of the aorta produced asymmetries in the location and position of streaks of high transWSS, and taper determined the persistence of the streaks down the aorta. These results reflect the importance of the fluctuating strength of Dean vortices in generating transWSS. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Polymyalgia rheumatica and temporal arthritis.

    Science.gov (United States)

    Epperly, T D; Moore, K E; Harrover, J D

    2000-08-15

    Polymyalgia rheumatica and temporal arteritis are closely related inflammatory conditions that affect different cellular targets in genetically predisposed persons. Compared with temporal arteritis, polymyalgla rheumatica is much more common, affecting one in 200 persons older than 50 years. Temporal arteritis, however, is more dangerous and can lead to sudden blindness. The diagnosis of polymyalgia rheumatica is based on the presence of a clinical syndrome consisting of fever, nonspecific somatic complaints, pain and stiffness in the shoulder and pelvic girdles, and an elevated erythrocyte sedimentation rate. Temporal arteritis typically presents with many of the same findings as polymyalgia rheumatica, but patients also have headaches and tenderness to palpation over the involved artery. Arterial biopsy usually confirms the diagnosis of temporal arteritis. Early diagnosis and treatment of polymyalgia rheumatica or temporal arteritis can dramatically improve patients' lives and return them to previous functional status. Corticosteroid therapy provides rapid and dramatic improvement of the clinical features of both conditions. Therapy is generally continued for six to 24 months. Throughout treatment, clinical condition is assessed periodically. Patients are instructed to see their physician immediately if symptoms recur or they develop new headache, jaw claudication or visual problems.

  4. Intracranial vessel wall imaging at 7.0 tesla MRI

    NARCIS (Netherlands)

    van der Kolk, A.G.

    2014-01-01

    Intracranial atherosclerosis is one of the main causes of ischemic stroke. Current conventional imaging techniques assessing intracranial arterial disease in vivo only visualize the vessel wall lumen instead of the pathological vessel wall itself. Therefore, not much is known about the imaging

  5. Arterial stiffness

    Directory of Open Access Journals (Sweden)

    Ursula Quinn

    2012-09-01

    Full Text Available Measurements of biomechanical properties of arteries have become an important surrogate outcome used in epidemiological and interventional cardiovascular research. Structural and functional differences of vessels in the arterial tree result in a dampening of pulsatility and smoothing of blood flow as it progresses to capillary level. A loss of arterial elastic properties results a range of linked pathophysiological changes within the circulation including increased pulse pressure, left ventricular hypertrophy, subendocardial ischaemia, vessel endothelial dysfunction and cardiac fibrosis. With increased arterial stiffness, the microvasculature of brain and kidneys are exposed to wider pressure fluctuations and may lead to increased risk of stroke and renal failure. Stiffening of the aorta, as measured by the gold-standard technique of aortic Pulse Wave Velocity (aPWV, is independently associated with adverse cardiovascular outcomes across many different patient groups and in the general population. Therefore, use of aPWV has been proposed for early detection of vascular damage and individual cardiovascular risk evaluation and it seems certain that measurement of arterial stiffness will become increasingly important in future clinical care. In this review we will consider some of the pathophysiological processes that result from arterial stiffening, how it is measured and factors that may drive it as well as potential avenues for therapy. In the face of an ageing population where mortality from atheromatous cardiovascular disease is falling, pathology associated with arterial stiffening will assume ever greater importance. Therefore, understanding these concepts for all clinicians involved in care of patients with cardiovascular disease will become vital.

  6. Falling walls

    CERN Multimedia

    It was 20 years ago this week that the Berlin wall was opened for the first time since its construction began in 1961. Although the signs of a thaw had been in the air for some time, few predicted the speed of the change that would ensue. As members of the scientific community, we can take a moment to reflect on the role our field played in bringing East and West together. CERN’s collaboration with the East, primarily through links with the Joint Institute for Nuclear Research, JINR, in Dubna, Russia, is well documented. Less well known, however, is the role CERN played in bringing the scientists of East and West Germany together. As the Iron curtain was going up, particle physicists on both sides were already creating the conditions that would allow it to be torn down. Cold war historian Thomas Stange tells the story in his 2002 CERN Courier article. It was my privilege to be in Berlin on Monday, the anniversary of the wall’s opening, to take part in a conference entitled &lsquo...

  7. Vascular narrowing in pulmonary arterial hypertension is heterogeneous: rethinking resistance

    NARCIS (Netherlands)

    Rol, N.; Timmer, E.M.; Faes, T.J.; Noordegraaf, A.V.; Grunberg, K.; Bogaard, H.J.; Westerhof, N.

    2017-01-01

    In idiopathic pulmonary arterial hypertension (PAH), increased pulmonary vascular resistance is associated with structural narrowing of small (resistance) vessels and increased vascular tone. Current information on pulmonary vascular remodeling is mostly limited to averaged increases in wall

  8. WITHDRAWN: The extended abdominal wall flap for transplantation.

    Science.gov (United States)

    Hollenbeck, S T; Senghaas, A; Turley, R; Ravindra, K V; Zenn, M R; Levin, L S; Erdmann, D

    2011-11-01

    Patients with extensive loss of abdominal wall tissue have few options for restoring the abdominal cavity. Composite tissue allotransplantation has been used for limited abdominal wall reconstruction in the setting of visceral transplantation, yet replacement of the entire abdominal wall has not been described. The purpose of this study was to determine the maximal abdominal skin surface available through an external iliac/femoral cuff-based pedicle. Five human cadaver abdominal walls were injected with methylene blue to analyze skin perfusion based on either the deep inferior epigastric artery (DIEA; n = 5) or a cuff of external iliac/femoral artery (n = 5) containing the deep circumflex iliac, deep inferior epigastric, superficial inferior epigastric, and the superficial circumflex iliac arteries. Abdominal wall flaps were taken full thickness from the costal margin to the mid-axial line and down to the pubic tubercle and proximal thigh. In all specimens, the deep inferior epigastric, deep circumflex iliac, superficial inferior epigastric, and the superficial circumflex iliac arteries were found to originate within a 4-cm cuff of the external iliac/femoral artery. Abdominal wall flaps injected through a unilateral external iliac/femoral segment had a significantly greater degree of total flap perfusion than those injected through the DIEA alone (76.5 +/- 4% versus 57.2 +/- 5%; Student t test, P DIEA vessel alone. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Performance assessment and optimization of Pulse Wave Imaging (PWI) in ex vivo canine aortas and in vivo normal human arteries.

    Science.gov (United States)

    Li, Ronny X; Qaqish, William W; Shahmirzadi, Danial; Konofagou, Elisa E

    2012-01-01

    The amplitude, velocity, and morphology of the arterial pulse wave may all provide valuable diagnostic information for cardiovascular pathology. Pulse Wave Imaging (PWI) is an ultrasound-based method developed by our group to noninvasively visualize and map the spatio-temporal variations of the pulse wave-induced vessel wall motion. Because PWI is capable of acquiring multiple wall motion waveforms successively along an imaged arterial segment over a single cardiac cycle in vivo, the regional morphological changes, amplitudes, and velocity (i.e. pulse wave velocity, or PWV) of the pulse wave can all be evaluated. In this study, an ex vivo setup was used to assess the effects of varying PWI image acquisition variables (beam density/frame rate and scanning orientation) and signal processing methods (beam sweep compensation scheme and waveform feature tracking) on the PWV estimation in order to validate the optimal parameters. PWI was also performed on the carotid arteries and abdominal aortas of six healthy volunteers for identification of several salient features of the waveforms over the entire cardiac cycle that may aid in assessing the morphological changes of the pulse wave. The ex vivo results suggest that the PWI temporal resolution is more important for PWV estimation than the PWI spatial resolution, and also that the reverse scanning orientation (i.e. beam sweeping direction opposite the direction of fluid flow) is advantageous due to higher precision and less dependence on the frame rate. In the in vivo waveforms, the highest precision PWV measurements were obtained by tracking the 50% upstroke of the waveforms. Finally, the dicrotic notch, reflected wave, and several inflection points were qualitatively identified in the carotid and aortic anterior wall motion waveforms and shown in one representative subject.

  10. Coil embolization of ruptured frontopolar artery aneurysm: case report.

    Science.gov (United States)

    Castaño-Leon, Ana M; Cicuendez, Marta; Paredes, Igor; Alen, Jose F; Navia, Pedro; Lagares, Alfonso

    2014-01-01

    Distal anterior cerebral artery aneurysms are infrequent. The most common location is at the bifurcation of the pericallosal and callosomarginal arteries. Cerebral artery anomalies can sometimes, at least partially, explain aneurysm formation in less common locations in relation to hemodynamic stress caused on the vascular wall. We report a very rare case of subarachnoid hemorrhage due to a ruptured frontopolar artery aneurysm as a part of an anomalous anterior cerebral artery complex that was, for the first time, treated with endovascular coiling. Copyright © 2012 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  11. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...... into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... multiply in interaction with project management technologies and how conventional linear conceptions of project time may be contested with the emergence of new non-human stakeholders and temporalities. Research limitations/implications – The study draws on ANT to show how animals can become stakeholders...

  12. Impact of age, sex and exercise on brachial and popliteal artery remodelling in humans.

    Science.gov (United States)

    Green, Daniel J; Swart, Anne; Exterkate, Anne; Naylor, Louise H; Black, Mark A; Cable, N Timothy; Thijssen, Dick H J

    2010-06-01

    To examine the impact of age, sex and exercise on wall thickness and remodelling in the popliteal and brachial arteries. We compared wall thickness, lumen diameter and wall:lumen ratios in the brachial and popliteal arteries of 15 young (Y, 25.4+/-0.8 yr; 7M 8W) and 16 older sedentary (OS, 58.8+/-1.1 yr; 8M 8W) subjects, with 12 of the OS group also studied following 12 and 24 weeks exercise training. Wall thickness and lumen diameter were higher in the popliteal than the brachial artery for both groups (P<0.05); wall:lumen ratio was similar between arteries. Comparison of the Y and OS groups revealed no impact on wall thickness, whereas diameter values were higher in OS subjects (P<0.05). Whilst there were no significant differences in wall thickness between men and women in the Y or OS groups, diameter was larger in men than in women for both arteries (P<0.05). After 24 weeks of training the wall thickness of both arteries decreased (P<0.01) and the wall:lumen ratio of the brachial (P<0.01) and the popliteal (P<0.05) decreased. The cross-sectional results suggest that ageing was associated with increased lumen diameter, although wall:lumen ratio remained unchanged. Wall:lumen ratio was higher in women than men, irrespective of subject age or the artery studied. This related primarily to differences in lumen diameter between the sexes, as wall thickness did not significantly differ between men and women. Our longitudinal data strongly suggest that exercise training is associated with beneficial effects on conduit artery wall thickness and wall:lumen ratio in both upper and lower limbs in humans. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  13. The efficacy of laparosonic coagulating shears for arterial division and hemostasis in porcine arteries.

    Science.gov (United States)

    Ninomiya, K; Kitano, S; Yoshida, T; Bandoh, T; Baatar, D; Matsumoto, T; Tsuboi, S

    2000-02-01

    Recently, the laparosonic coagulating shears (LCS) have been used widely in laparoscopic surgery. In the current study, the usefulness of LCS for arterial division and hemostasis was examined in porcine arteries. Porcine arteries of several diameters (1, 3, and 5 mm) were removed and divided using LCS with different blade modes: shear, blunt, and flat. The division time and bursting pressure were registered. Additionally, divided sections stained by the Azan-Mallory method were observed microscopically. The division time was dependent on the blade modes used. With the flat mode, the bursting pressure of 5-mm arteries was significantly higher than the bursting pressure with shear and blunt modes. Histologically, cavitation and mild degeneration of the vessel walls occurred adjacent to the cutting edge. The LCS is a safe and useful device for arterial division and hemostasis for 5-mm arteries if an adequate blade mode is used.

  14. Occlusive Peripheral Arterial Disease

    Science.gov (United States)

    ... but also to the worsening of the disease. Obstructive peripheral arterial disease most commonly develops in the arteries of the legs, including the two branches of the aorta (iliac arteries), main arteries of the thighs (femoral arteries), of ... arterial disease may also develop in the part ...

  15. Heterogeneity in conduit artery function in humans: impact of arterial size.

    Science.gov (United States)

    Thijssen, Dick H J; Dawson, Ellen A; Black, Mark A; Hopman, Maria T E; Cable, N Timothy; Green, Daniel J

    2008-11-01

    To determine whether conduit artery size affects functional responses, we compared the magnitude, time course, and eliciting shear rate stimulus for flow-mediated dilation (FMD) in healthy men (n = 20; 31 +/- 7 yr). Upper limb (brachial and radial) and lower limb (common and superficial femoral) FMD responses were simultaneously assessed, whereas popliteal responses were measured in the same subjects during a separate visit. Glyceryl trinitrate (GTN)-mediated responses were similarly examined. Edge detection and wall tracking of high-resolution B-mode arterial ultrasound images, combined with synchronized Doppler waveform envelope analysis, were used to calculate conduit artery diameter, blood flow, and shear rate continuously across the cardiac cycle. Baseline artery size correlated inversely with the FMD response (r = -0.57, P < 0.001). Within-artery comparisons revealed a significant inverse correlation between artery size and FMD% for the radial (r = -0.66, P = 0.001), brachial (r = -0.55, P = 0.01), and popliteal artery (r = -0.48, P = 0.03), but not for the superficial and common femoral artery. Normalization of FMD responses for differences in eliciting shear rate did not abolish the between-artery relationship for artery function and size (r = -0.48, P < 0.001), suggesting that differences between artery function responses were not entirely due to size-related differences in shear rate. This was reinforced by a significant between-artery correlation for GTN responses and baseline artery size (r = -0.74, P < 0.001). In summary, systematic differences exist in vascular function responses of conduit arteries that differ in size. This raises the possibility that differences in artery size within or between individuals may influence functional responses.

  16. Pediatric nonaortic arterial aneurysms.

    Science.gov (United States)

    Davis, Frank M; Eliason, Jonathan L; Ganesh, Santhi K; Blatt, Neal B; Stanley, James C; Coleman, Dawn M

    2016-02-01

    Pediatric arterial aneurysms are extremely uncommon. Indications for intervention remain poorly defined and treatments vary. The impetus for this study was to better define the contemporary surgical management of pediatric nonaortic arterial aneurysms. A retrospective analysis was conducted of 41 children with 61 aneurysms who underwent surgical treatment from 1983 to 2015 at the University of Michigan. Arteries affected included: renal (n = 26), femoral (n = 7), iliac (n = 7), superior mesenteric (n = 4), brachial (n = 3), carotid (n = 3), popliteal (n = 3), axillary (n = 2), celiac (n = 2), ulnar (n = 2), common hepatic (n = 1), and temporal (n = 1). Intracranial aneurysms and aortic aneurysms treated during the same time period were not included in this study. Primary outcomes analyzed were postoperative complications, mortality, and freedom from reintervention. The study included 27 boys and 14 girls, with a median age of 9.8 years (range, 2 months-18 years) and a weight of 31.0 kg (range, 3.8-71 kg). Multiple aneurysms existed in 14 children. Obvious factors that contributed to aneurysmal formation included: proximal juxta-aneurysmal stenoses (n = 14), trauma (n = 12), Kawasaki disease (n = 4), Ehlers-Danlos type IV syndrome (n = 1), and infection (n = 1). Preoperative diagnoses were established using arteriography (n = 23), magnetic resonance angiography (n = 6), computed tomographic arteriography (n = 5), or ultrasonography (n = 7), and confirmed during surgery. Indications for surgery included risk of expansion and rupture, potential thrombosis or embolization of aneurysmal thrombus, local soft tissue and nerve compression, and secondary hypertension in the case of renal artery aneurysms. Primary surgical techniques included: aneurysm resection with reanastomsis, reimplantation, or angioplastic closure (n = 16), interposition (n = 10) or bypass grafts (n = 2), ligation (n = 9), plication (n = 8), endovascular occlusion (n = 3), and nephrectomy (n = 4) in

  17. Arterial Stiffness and Renal Replacement Therapy: A Controversial Topic.

    Science.gov (United States)

    Fischer, Edmundo Cabrera; Zócalo, Yanina; Galli, Cintia; Wray, Sandra; Bia, Daniel

    2015-01-01

    The increase of arterial stiffness has been to have a significant impact on predicting mortality in end-stage renal disease patients. Pulse wave velocity (PWV) is a noninvasive, reliable parameter of regional arterial stiffness that integrates the vascular geometry and arterial wall intrinsic elasticity and is capable of predicting cardiovascular mortality in this patient population. Nevertheless, reports on PWV in dialyzed patients are contradictory and sometimes inconsistent: some reports claim the arterial wall stiffness increases (i.e., PWV increase), others claim that it is reduced, and some even state that it augments in the aorta while it simultaneously decreases in the brachial artery pathway. The purpose of this study was to analyze the literature in which longitudinal or transversal studies were performed in hemodialysis and/or peritoneal dialysis patients, in order to characterize arterial stiffness and the responsiveness to renal replacement therapy.

  18. Arterial Stiffness and Renal Replacement Therapy: A Controversial Topic

    Directory of Open Access Journals (Sweden)

    Edmundo Cabrera Fischer

    2015-01-01

    Full Text Available The increase of arterial stiffness has been to have a significant impact on predicting mortality in end-stage renal disease patients. Pulse wave velocity (PWV is a noninvasive, reliable parameter of regional arterial stiffness that integrates the vascular geometry and arterial wall intrinsic elasticity and is capable of predicting cardiovascular mortality in this patient population. Nevertheless, reports on PWV in dialyzed patients are contradictory and sometimes inconsistent: some reports claim the arterial wall stiffness increases (i.e., PWV increase, others claim that it is reduced, and some even state that it augments in the aorta while it simultaneously decreases in the brachial artery pathway. The purpose of this study was to analyze the literature in which longitudinal or transversal studies were performed in hemodialysis and/or peritoneal dialysis patients, in order to characterize arterial stiffness and the responsiveness to renal replacement therapy.

  19. Recapitulation of Developing Artery Muscularization in Pulmonary Hypertension

    Directory of Open Access Journals (Sweden)

    Abdul Q. Sheikh

    2014-03-01

    Full Text Available Excess smooth muscle accumulation is a key component of many vascular disorders, including atherosclerosis, restenosis, and pulmonary artery hypertension, but the underlying cell biological processes are not well defined. In pulmonary artery hypertension, reduced pulmonary artery compliance is a strong independent predictor of mortality, and pathological distal arteriole muscularization contributes to this reduced compliance. We recently demonstrated that embryonic pulmonary artery wall morphogenesis consists of discrete developmentally regulated steps. In contrast, poor understanding of distal arteriole muscularization in pulmonary artery hypertension severely limits existing therapies that aim to dilate the pulmonary vasculature but have modest clinical benefit and do not prevent hypermuscularization. Here, we show that most pathological distal arteriole smooth muscle cells, but not alveolar myofibroblasts, derive from pre-existing smooth muscle. Furthermore, the program of distal arteriole muscularization encompasses smooth muscle cell dedifferentiation, distal migration, proliferation, and then redifferentiation, thereby recapitulating many facets of arterial wall development.

  20. Review: Mechanical Characterization of Carotid Arteries and Atherosclerotic Plaques

    NARCIS (Netherlands)

    Korte, C.L. de; Fekkes, S.; Nederveen, A.J.; Manniesing, R.; Hansen, H.R.

    2016-01-01

    Cardiovascular disease (CVD) is a leading cause of death and is in the majority of cases due to the formation of atherosclerotic plaques in arteries. Initially, thickening of the inner layer of the arterial wall occurs. Continuation of this process leads to plaque formation. The risk of a plaque to

  1. Deep Circumflex Iliac Artery Pseudoaneurysm as a Complication of Paracentesis

    Directory of Open Access Journals (Sweden)

    Bhawna Satija

    2012-01-01

    Full Text Available We report a case of a pseudoaneurysm arising from the deep circumflex iliac artery, in an end-stage renal disease patient with gross ascitis, presenting with an anterior abdominal wall hematoma following paracentesis. Duplex Doppler sonography confirmed the presence of the pseudoaneurysm and multidetector computed tomography angiography delineated the detailed arterial anatomy.

  2. Vascular Aging and Arterial Stiffness

    Directory of Open Access Journals (Sweden)

    Luana de Rezende Mikael

    Full Text Available Abstract Cardiovascular diseases (CVD account annually for almost one third of all deaths worldwide. Among the CVD, systemic arterial hypertension (SAH is related to more than half of those outcomes. Type 2 diabetes mellitus is an independent risk factor for SAH because it causes functional and structural damage to the arterial wall, leading to stiffness. Several studies have related oxidative stress, production of free radicals, and neuroendocrine and genetic changes to the physiopathogenesis of vascular aging. Indirect ways to analyze that aging process have been widely studied, pulse wave velocity (PWV being considered gold standard to assess arterial stiffness, because there is large epidemiological evidence of its predictive value for cardiovascular events, and it requires little technical knowledge to be performed. A pulse wave is generated during each cardiac contraction and travels along the arterial bed until finding peripheral resistance or any bifurcation point, determining the appearance of a reflected wave. In young individuals, arteries tend to be more elastic, therefore, the reflected wave occurs later in the cardiac cycle, reaching the heart during diastole. In older individuals, however, the reflected wave occurs earlier, reaching the heart during systole. Because PWV is an important biomarker of vascular damage, highly valuable in determining the patient’s global cardiovascular risk, we chose to review the articles on vascular aging in the context of cardiovascular risk factors and the tools available to the early identification of that damage.

  3. Severe gastric variceal haemorrhage due to splenic artery thrombosis and consecutive arterial bypass

    Directory of Open Access Journals (Sweden)

    Wasmuth Hermann E

    2011-06-01

    Full Text Available Abstract Background Upper gastrointestinal haemorrhage is mainly caused by ulcers. Gastric varicosis due to portal hypertension can also be held responsible for upper gastrointestinal bleeding. Portal hypertension causes the development of a collateral circulation from the portal to the caval venous system resulting in development of oesophageal and gastric fundus varices. Those may also be held responsible for upper gastrointestinal haemorrhage. Case presentation In this study, we describe the case of a 69-year-old male with recurrent severe upper gastrointestinal bleeding caused by arterial submucosal collaterals due to idiopathic splenic artery thrombosis. The diagnosis was secured using endoscopic duplex ultrasound and angiography. The patient was successfully treated with a laparoscopic splenectomy and complete dissection of the short gastric arteries, resulting in the collapse of the submucosal arteries in the gastric wall. Follow-up gastroscopy was performed on the 12th postoperative week and showed no signs of bleeding and a significant reduction in the arterial blood flow within the gastric wall. Subsequent follow-up after 6 months also showed no further gastrointestinal bleeding as well as subjective good quality of life for the patient. Conclusion Submucosal arterial collaterals must be excluded by endosonography via endoscopy in case of recurrent upper gastrointestinal bleeding. Laparoscopic splenectomy provides adequate treatment in preventing any recurrent bleeding, if gastric arterial collaterals are caused by splenic artery thrombosis.

  4. The effect of sumatriptan on cephalic arteries

    DEFF Research Database (Denmark)

    Amin, Faisal Mohammad; Asghar, Mohammad Sohail; Ravneberg, Julie W

    2013-01-01

    AIM: To explore a possible differential effect of sumatriptan on extracerebral versus cerebral arteries, we examined the superficial temporal (STA), middle meningeal (MMA), extracranial internal carotid (ICAextra), intracranial internal carotid (ICAintra), middle cerebral (MCA) and basilar arteries...... (BA). METHODS: The arterial circumferences were recorded blindly using high-resolution magnetic resonance angiography before and after subcutaneous sumatriptan injection (6 mg) in 18 healthy volunteers. RESULTS: We found significant constrictions of MMA (16.5%), STA (16.4%) and ICAextra (15.2%) ( P...

  5. Great Wall of China

    Science.gov (United States)

    2001-01-01

    This ASTER sub-image covers a 12 x 12 km area in northern Shanxi Province, China, and was acquired January 9, 2001. The low sun angle, and light snow cover highlight a section of the Great Wall, visible as a black line running diagonally through the image from lower left to upper right. The Great Wall is over 2000 years old and was built over a period of 1000 years. Stretching 4500 miles from Korea to the Gobi Desert it was first built to protect China from marauders from the north.This image is located at 40.2 degrees north latitude and 112.8 degrees east longitude.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats, monitoring potentially active volcanoes, identifying crop stress, determining cloud morphology and physical properties, wetlands Evaluation, thermal pollution monitoring, coral reef degradation, surface temperature mapping of soils and geology, and measuring surface

  6. Quantitative Measurements of Competitive Flow in Left Internal Mammary Artery Bypass Grafts

    NARCIS (Netherlands)

    Spoor, Pien; Halfwerk, F.R.; Hagmeijer, Rob; Grandjean, J.G.

    2017-01-01

    OBJECTIVE: A low flow rate with diminished wall shear stress in arteries can cause intima hyperplasia and diameter reduction. In coronary artery bypass grafting (CABG) a low flow rate through the graft can cause graft failure (i.e. the string sign effect and occlusion). Arterial grafts bypassing an

  7. Walled Carotid Bifurcation Phantoms for Imaging Investigations of Vessel Wall Motion and Blood Flow Dynamics.

    Science.gov (United States)

    Chee, Adrian J Y; Ho, Chung Kit; Yiu, Billy Y S; Yu, Alfred C H

    2016-07-18

    As a major application domain of vascular ultrasound, the carotid artery has long been the subject of anthropomorphic phantom design. It is nevertheless not trivial to develop walled carotid phantoms that are compatible for use in integrative imaging of carotid wall motion and flow dynamics. In this paper, we present a novel phantom design protocol that can enable efficient fabrication of walled carotid bifurcation phantoms with: (i) high acoustic compatibility, (ii) artery-like vessel elasticity, and (iii) stenotic narrowing feature. Our protocol first involved direct fabrication of the vessel core and an outer mold using computer-aided design tools and 3-D printing technology; these built parts were then used to construct an elastic vessel tube through investment casting of a polyvinyl alcohol containing mixture, and an agar-gelatin tissue mimicking slab was formed around the vessel tube. For demonstration, we applied our protocol to develop a set of healthy and stenosed (25%, 50%, 75%) carotid bifurcation phantoms. Plane wave imaging experiments were performed on these phantoms using an ultrasound scanner with channel-level configurability. Results show that the wall motion dynamics of our phantoms agreed with pulse wave propagation in an elastic vessel (pulse wave velocity of 4.67±0.71 m/s measured at the common carotid artery), and their flow dynamics matched the expected ones in healthy and stenosed bifurcation (recirculation and flow jet formation observed). Integrative imaging of vessel wall motion and blood flow dynamics in our phantoms was also demonstrated, from which we observed fluid-structure interaction differences between healthy and diseased bifurcation phantoms. These findings show that the walled bifurcation phantoms developed with our new protocol are useful in vascular imaging studies that individually or jointly assess wall motion and flow dynamics.

  8. Woven coronary artery: differential diagnosis with diffuse intracoronary thrombosis.

    Science.gov (United States)

    Martuscelli, E; Romeo, F; Giovannini, M; Nigri, A

    2000-04-01

    Woven coronary malformation is characterized by the branching of a major epicardial coronary artery into thin channels which then merge again in a normal conduit. The angiogram can suggest a filling defect instead of a malformation and an undue coronary angioplasty could be performed determining some damage to the arterial wall. In this case report we describe a patient with a stenosis on the left anterior descending coronary artery and a woven coronary artery on the right coronary artery. In 1995 a coronary angioplasty was performed on the left anterior descending coronary artery. Four years later a coronary angiogram did not show any changes in the right coronary artery. In this patient the malformation did not induce any reduction in the coronary reserve as shown at cardiac scintigraphy. We need more information about the natural history of such a malformation.

  9. Constitutive description of human femoropopliteal artery aging.

    Science.gov (United States)

    Kamenskiy, Alexey; Seas, Andreas; Deegan, Paul; Poulson, William; Anttila, Eric; Sim, Sylvie; Desyatova, Anastasia; MacTaggart, Jason

    2017-04-01

    Femoropopliteal artery (FPA) mechanics play a paramount role in pathophysiology and the artery's response to therapeutic interventions, but data on FPA mechanical properties are scarce. Our goal was to characterize human FPAs over a wide population to derive a constitutive description of FPA aging to be used for computational modeling. Fresh human FPA specimens ([Formula: see text]) were obtained from [Formula: see text] predominantly male (80 %) donors 54±15 years old (range 13-82 years). Morphometric characteristics including radius, wall thickness, opening angle, and longitudinal pre-stretch were recorded. Arteries were subjected to multi-ratio planar biaxial extension to determine constitutive parameters for an invariant-based model accounting for the passive contributions of ground substance, elastin, collagen, and smooth muscle. Nonparametric bootstrapping was used to determine unique sets of material parameters that were used to derive age-group-specific characteristics. Physiologic stress-stretch state was calculated to capture changes with aging. Morphometric and constitutive parameters were derived for seven age groups. Vessel radius, wall thickness, and circumferential opening angle increased with aging, while longitudinal pre-stretch decreased ([Formula: see text]). Age-group-specific constitutive parameters portrayed orthotropic FPA stiffening, especially in the longitudinal direction. Structural changes in artery wall elastin were associated with reduction of physiologic longitudinal and circumferential stretches and stresses with age. These data and the constitutive description of FPA aging shed new light on our understanding of peripheral arterial disease pathophysiology and arterial aging. Application of this knowledge might improve patient selection for specific treatment modalities in personalized, precision medicine algorithms and could assist in device development for treatment of peripheral artery disease.

  10. Niflumic Acid Attenuated Pulmonary Artery Tone and Vascular Structural Remodeling of Pulmonary Arterial Hypertension Induced by High Pulmonary Blood Flow In Vivo.

    Science.gov (United States)

    Wang, Kai; Ma, Jianfa; Pang, Yusheng; Lao, Jinquan; Pan, Xuanren; Tang, Qiaoyun; Zhang, Feng; Su, Danyan; Qin, Suyuan; Shrestha, Arnav Prasad

    2015-10-01

    Calcium-activated chloride channels (CaCCs) play a vital role in regulating pulmonary artery tone during pulmonary arterial hypertension (PAH) induced by high blood flow. The role of CaCCs inhibitor niflumic acid (NFA) in vivo during this process requires further investigation. We established the PAH model by abdominal shunt surgery and treated with NFA in vivo. Fifty rats were randomly divided into normal, sham, shunt, NFA group 1 (0.2 mg/kg), and NFA group 2 (0.4 mg/kg). Pathological changes, right ventricle hypertrophy index, arterial wall area/vessel area, and arterial wall thickness/vessel external diameter were analyzed. Then contraction reactions of pulmonary arteries were measured. Finally, the electrophysiological characteristics of pulmonary arterial smooth muscle cells were investigated using patch-clamp technology. After 11 weeks of shunting, PAH developed, accompanied with increased right ventricle hypertrophy index, arterial wall area/vessel area, and arterial wall thickness/vessel external diameter. In the NFA treatment groups, the pressure and pathological changes were alleviated. The pulmonary artery tone in the shunt group increased, whereas it decreased after NFA treatment. The current density of CaCC was higher in the shunt group, and it was decreased in the NFA treatment groups. In conclusion, NFA attenuated pulmonary artery tone and structural remodeling in PAH induced by high pulmonary blood flow in vivo. CaCCs were involved and the augmented current density was alleviated by NFA treatment.

  11. The arterial blood supply of the temporomandibular joint: an anatomical study and clinical implications.

    Science.gov (United States)

    Cuccia, Antonino Marco; Caradonna, Carola; Caradonna, Domenico; Anastasi, Giuseppe; Milardi, Demetrio; Favaloro, Angelo; De Pietro, Anita; Angileri, Tommaso Maurizio; Caradonna, Luigi; Cutroneo, Giuseppina

    2013-03-01

    The aim of this study was to analyze three-dimensional images of the arterial supply to the temporomandibular joint. Ten patients (five men and five women, mean age 36 years) without signs or symptoms of temporomandibular disorders, who underwent contrast-enhanced computed tomographic (CT) scanning with intravenous contrast, were studied. The direct volume rendering technique of CT images was used, and a data set of images to visualize the vasculature of the human temporomandibular joint in three dimensions was created. After elaboration of the data through post-processing, the arterial supply of the temporomandibular joint was studied. The analysis revealed the superficial temporal artery, the anterior tympanic artery, the deep temporal artery, the auricular posterior artery, the transverse facial artery, the middle meningeal artery, and the maxillary artery with their branches as the main arterial sources for the lateral and medial temporomandibular joint. The direct volume rendering technique was found to be successful in the assessment of the arterial supply to the temporomandibular joint. The superficial temporal artery and maxillary artery ran along the lateral and medial sides of the condylar neck, suggesting that these arteries are at increased risk during soft-tissue procedures such as an elective arthroplasty of the temporomandibular joint.

  12. The arterial blood supply of the temporomandibular joint: an anatomical study and clinical implications

    Energy Technology Data Exchange (ETDEWEB)

    Cuccia, Antonino Marco; Caradonna, Carola; Caradonna, Domenico [Dept. of Surgical and Oncological Disciplines, University of Palermo, Palermo (Italy); Anastasi, Giuseppe; Milardi, Demetrio; Favaloro, Angelo; Caradonna, Luigi; Cutroneo, Giuseppina [Biomorphology and Biotechnologies, University of Messina, Messina (Italy); De Pietro, Anita; Angileri, Tommaso Maurizio [Villa Santa Teresa, Diagnostica per Immagini, Palermo (Italy)

    2013-03-15

    The aim of this study was to analyze three-dimensional images of the arterial supply to the temporomandibular joint. Ten patients (five men and five women, mean age 36 years) without signs or symptoms of temporomandibular disorders, who underwent contrast-enhanced computed tomographic (CT) scanning with intravenous contrast, were studied. The direct volume rendering technique of CT images was used, and a data set of images to visualize the vasculature of the human temporomandibular joint in three dimensions was created. After elaboration of the data through post-processing, the arterial supply of the temporomandibular joint was studied. The analysis revealed the superficial temporal artery, the anterior tympanic artery, the deep temporal artery, the auricular posterior artery, the transverse facial artery, the middle meningeal artery, and the maxillary artery with their branches as the main arterial sources for the lateral and medial temporomandibular joint. The direct volume rendering technique was found to be successful in the assessment of the arterial supply to the temporomandibular joint. The superficial temporal artery and maxillary artery ran along the lateral and medial sides of the condylar neck, suggesting that these arteries are at increased risk during soft-tissue procedures such as an elective arthroplasty of the temporomandibular joint.

  13. Surgical repair for a coronary-pulmonary artery fistula with a saccular aneurysm of the coronary artery.

    Science.gov (United States)

    Izumi, Kenta; Hisata, Yoichi; Hazam, Shiro

    2009-06-01

    The patient, a 69-year-old woman, had been diagnosed with a heart murmur. A chest X-ray at a local clinic had shown an abnormal shadow. Since CT revealed a 3-cm-diameter mass close to the pulmonary artery, we performed a coronary angiography and diagnosed her as having a coronary artery aneurysm associated with a coronary-pulmonary artery fistula. We incised the aneurysm under cardiac arrest, the wall of which had three openings that were suture closed from the inside and outside. The coronary-pulmonary artery fistula was suture closed. A postoperative angiography confirmed the disappearance of the coronary artery aneurysm and the abnormal blood vessels. The patient had an uneventful postoperative course and was discharged on postoperative day 15. We report a rare case of coronary-pulmonary artery fistula with a coronary artery aneurysm for which surgery was followed by an uneventful postoperative course.

  14. [Arterial stiffness in patients with chronic obstructive pulmonary disease].

    Science.gov (United States)

    2012-01-01

    To estimate arterial stiffness (AS) in patients with chronic obstructive pulmonary disease (COPD). A total of 112 COPD patients over 40 years of age entered a population-based trial. The patients with coronary heart diseases, peripheral vascular atherosclerosis, other severe chronic diseases in exacerbation were withdrawn. The control group consisted of 26 healthy volunteers matched by gender and age. AS was measured at arteriograph "Tensioclinic" ("Tensiomed", Hungary). COPD patients, first of all elderly ones, had abnormal properties of arterial wall. Increased arterial rigidity and pulse wave reflection (accelerated pulse wave velocity and high index of augmentation) are strongly associated with elevation of central arterial pressure. High arterial wall stiffness in COPD patients suggests an increased risk of cardiovascular diseases that necessitates examination in prospective studies.

  15. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  16. Carotid artery surgery

    Science.gov (United States)

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... results of stenting versus endarterectomy for carotid-artery stenosis. N Engl J Med . 2016;374(11):1021- ...

  17. Carotid Artery Disease

    Science.gov (United States)

    ... head with blood. If you have carotid artery disease, the arteries become narrow or blocked, usually because ... other substances found in the blood. Carotid artery disease is serious because it can block the blood ...

  18. Coronary artery disease (image)

    Science.gov (United States)

    ... through these arteries is critical for the heart. Coronary artery disease usually results from the build-up of fatty material and plaque, a condition called atherosclerosis. As the coronary arteries narrow, the flow of blood to the ...

  19. Peripheral arterial line (image)

    Science.gov (United States)

    A peripheral arterial line is a small, short plastic catheter placed through the skin into an artery of the arm or leg. The purpose of a peripheral arterial line is to allow continuous monitoring of blood pressure ...

  20. Bipolar Cutting Method: Another Technique for Harvesting Donor Artery With Histological Investigation.

    Science.gov (United States)

    Tokugawa, Joji; Ogura, Kanako; Yatomi, Kenji; Kudo, Kentaro; Hishii, Makoto; Tanikawa, Rokuya; Kamiyama, Hiroyasu

    2018-01-01

    Safe and appropriate harvesting of the donor scalp vessel is the first key procedure in any type of bypass surgery. To use the so-called bipolar cutting method to harvest donor arteries, in which the donor arteries are skeletonized with bipolar cautery. The surgical procedure and the preparation of the equipment of the bipolar cutting method are described. The surgical results and histological assessment are presented. The bipolar generator was set at 50 Malis units in the coagulation mode. Under the surgical microscope, the surrounding tissue of the donor artery was divided and coagulated with the bipolar forceps. The donor artery was completely skeletonized to provide adequate length. After the recipient artery was chosen and the anastomosis site was decided, the distal end of the donor artery was cut to the appropriate length. The remnant fragment of the donor artery was histologically investigated for any damage to the arterial wall. The specimen was cut longitudinally to observe the entire length of the arterial wall and stained with hematoxylin and eosin and elastica van Gieson. A total of 30 bypass surgeries were performed and 38 histological specimens were obtained between February 2015 and June 2016. The success rate of the bypass was 96%. No arterial wall damage such as thermal injury or dissection of the wall was recognized in any of the specimens. The bipolar cutting method is a useful and safe method for harvesting donor scalp artery.

  1. The parasitic cell wall of Coccidioides immitis.

    Science.gov (United States)

    Cole, G T; Hung, C Y

    2001-01-01

    Coccidioides immitis is a human respiratory pathogen characterized by a parasitic cycle that is unique among fungi that cause systemic mycoses. Biochemical, molecular and immunological studies of the cell wall of C. immitis have focused on three distinct events of parasitic cell differentiation: isotropic growth, segmentation and endosporulation. Current investigations of each developmental phase in vitro include the identification, expression analysis, and disruption of synthase and hydrolase genes that are suspected to have key roles in morphogenesis. Temporal expression of families of beta-glucosidase and chitinase genes are of particular interest because their products may participate in wall modification during both isotropic growth and endosporulation and, thereby, represent potential molecular targets for novel antifungal drugs. Furthermore, our immunological studies of these and other isolated parasitic cell-wall components have resulted in the identification of antigens with demonstrated impact on host response to coccidioidal infection. C. immitis has proved to be an excellent model for fungal cell-wall research.

  2. Pattern of division and distribution of the mesenteric arteries in nutria (Myocastor coypus – Rodentia: Mammalia

    Directory of Open Access Journals (Sweden)

    Adelvino Parizzi

    2006-03-01

    Full Text Available For the recognition of the anatomical pattern of the mesenteric arteries, ten adults nutria (Myocastor coypus, males and females, were dissected, and the following results were obtained: a The cranial mesenteric artery appears from the ventral face of the abdominal aorta, close to the celiac artery (70%, or as a common trunk with it (30%. b The direct branches of the cranial mesenteric artery are the caudal pancreaticoduodenal (100%, middle colic (100%, duodenojejunal (90%, pancreatic (10%, hepatic (10%, right colic (100%, jejunal (100%, ileocolic (100% and ileal (100% arteries. The caudal mesenteric artery appears from the ventral face of the abdominal aorta, immediately cranial to the emergence of the external iliac arteries, and it separates to form the cranial rectal and left colic arteries. This left colic artery can be anastomosed (30%, along the wall of the descending colon, with the descending branch of the middle colic artery.

  3. Non-arterial assessment of blood gas status in patients with chronic pulmonary disease.

    OpenAIRE

    Elborn, J. S.; Finch, M. B.; Stanford, C. F.

    1991-01-01

    Assessment of blood gas status is important in the management of patients with chronic pulmonary disease. Arterial puncture is often painful and may damage the arterial wall. Measurement of oxygen saturation by transcutaneous oximetry offers a non-invasive alternative to arterial methods but does not allow assessment of partial pressure of carbon dioxide. We have examined the value of oximetry and dorsal hand venous carbon dioxide as an alternative to arterial puncture. Transcutaneous oxygen ...

  4. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output

    DEFF Research Database (Denmark)

    Smerup, Morten Holdgaard; Damkjær, Mads; Brøndum, Emil

    2016-01-01

    by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It remains enigmatic, however, how the normal-sized giraffe heart generates such massive arterial pressures.We hypothesized that giraffe hearts have a small...... intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic...

  5. Intima-media thickness of peripheral arteries in asymptomatic cigarette smokers.

    Science.gov (United States)

    van den Berkmortel, F W; Smilde, T J; Wollersheim, H; van Langen, H; de Boo, T; Thien, T

    2000-06-01

    Although it is known that smoking is associated with an increase in arterial wall thickness, most studies have been performed in heterogeneous groups of older age, already suffering from atherosclerotic diseases or having additional cardiovascular risk factors. The purpose of this study is to assess the effect on arterial wall thickness of the carotid and femoral artery in cigarette smokers. In a cross-sectional study, intima-media thickness of the common and internal carotid artery, carotid bulb and common femoral artery was determined with the use of a B-mode ultrasound device, in 184 (44.3+/-9.0 years) cigarette smokers for whom smoking is the single cardiovascular risk factor. Comparisons were made with 56 non-smokers, matching in age and gender. The posterior walls of both carotid bulbs (right: P=0.0005; left: P=0.02) and of the internal carotid arteries (right: P=0.004; left: P=0.003) as well as the posterior wall of the right common carotid artery (P=0.02) and of the right common femoral artery (P<0.0001) were thicker in smokers. Cigarette smoking as the single cardiovascular risk factor causes wall thickening of the carotid and femoral arteries, which indicates that early atherosclerosis is already present in smokers entering middle age.

  6. Charged Domain Walls

    OpenAIRE

    Campanelli, L.; Cea, P.; Fogli, G. L.; Tedesco, L.

    2003-01-01

    In this paper we investigate Charged Domain Walls (CDW's), topological defects that acquire surface charge density $Q$ induced by fermion states localized on the walls. The presence of an electric and magnetic field on the walls is also discussed. We find a relation in which the value of the surface charge density $Q$ is connected with the existence of such topological defects.

  7. Radial Artery Aneurysm

    Directory of Open Access Journals (Sweden)

    Ali Fedakar

    2011-04-01

    Full Text Available Upper limb aneurysms are less frequently seen than the other aneurysm. Radial arterial aneurysm is usually associated with the trauma. Interventional procedures can cause pseudoaneurysm at the radial artery puncture sites. Radial artery aneurysm may cause the thromboembolic events at the fingers and the hand. We present a case of isolated radial arterial aneurysm with idiopathic origin.

  8. Single umbilical artery

    Directory of Open Access Journals (Sweden)

    Shanthi Ramesh

    2015-01-01

    Full Text Available The umbilical cord usually contains two arteries and one vein. The vein carries the oxygenated blood from the placenta to the fetus. The arteries carry the deoxygenated blood and the waste products from the fetus to the placenta. Occasionally, primary agenesis or secondary atrophy of one of the arteries occurs resulting in single umbilical artery.

  9. Single umbilical artery

    OpenAIRE

    Shanthi Ramesh; Sangeetha Hariprasath; Gunasekaran Anandan; P John Solomon; Vijayakumar, V.

    2015-01-01

    The umbilical cord usually contains two arteries and one vein. The vein carries the oxygenated blood from the placenta to the fetus. The arteries carry the deoxygenated blood and the waste products from the fetus to the placenta. Occasionally, primary agenesis or secondary atrophy of one of the arteries occurs resulting in single umbilical artery.

  10. Single umbilical artery.

    Science.gov (United States)

    Ramesh, Shanthi; Hariprasath, Sangeetha; Anandan, Gunasekaran; Solomon, P John; Vijayakumar, V

    2015-04-01

    The umbilical cord usually contains two arteries and one vein. The vein carries the oxygenated blood from the placenta to the fetus. The arteries carry the deoxygenated blood and the waste products from the fetus to the placenta. Occasionally, primary agenesis or secondary atrophy of one of the arteries occurs resulting in single umbilical artery.

  11. Arterial hypertension in patients with heart failure.

    Science.gov (United States)

    Díez, Javier

    2014-04-01

    Hypertensive heart disease (HHD) has been considered the adaptive hypertrophy of the left ventricle wall to increased blood pressure. Recent findings in hypertensive animals and patients now challenge this paradigm by showing that HHD also results from pathologic structural remodeling of the myocardium in response to hemodynamic and nonhemodynamic factors that are altered in arterial hypertension. The possibility that hypertensive patients predisposed to develop heart failure may be detected before the appearance of clinical manifestations provides a new way to prevent this major arterial complication. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Feeding Arteries of Primary Tongue Cancers on Intra-arterial Infusion Chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kamitani, Takeshi, E-mail: kamitani@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan); Kawanami, Satoshi, E-mail: kawanami-01@mac.com [Kyushu University, Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences (Japan); Asayama, Yoshiki, E-mail: asayama@radiol.med.kyushu-u.ac.jp; Matsuo, Yoshio, E-mail: yymatsuo@radiol.med.kyushu-u.ac.jp; Yonezawa, Masato, E-mail: ymasato@radiol.med.kyushu-u.ac.jp; Yamasaki, Yuzo, E-mail: yyama@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan); Nagao, Michinobu, E-mail: minagao@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences (Japan); Yamanouchi, Torahiko, E-mail: tora0228@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan); Yabuuchi, Hidetake, E-mail: h-yabu@med.kyushu-u.ac.jp [Kyushu University, Department of Health Sciences, Graduate School of Medical Sciences (Japan); Nakamura, Katsumasa, E-mail: nakam@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan); Nakashima, Torahiko, E-mail: nakatora@qent.med.kyushu-u.ac.jp [Kyushu University, Department of Otorhinolaryngology, Graduate School of Medical Sciences (Japan); Honda, Hiroshi, E-mail: honda@radiol.med.kyushu-u.ac.jp [Kyushu University, Department of Clinical Radiology, Graduate School of Medical Sciences (Japan)

    2016-02-15

    PurposeTo evaluate the frequency and the predictive factor of each feeding artery on intra-arterial infusion chemotherapy (IAIC) in primary tongue cancer.Materials and MethodsWe retrospectively evaluated 20 patients who received IAIC for primary tongue cancer. The main and accompanying feeding arteries were identified on super-selective angiography of the branches of the external carotid artery. Tumor diameter, and extension to the contralateral side, tongue extrinsic muscles (TEMs), and lateral mesopharyngeal wall were determined based on magnetic resonance imaging or computed tomography findings.ResultsThe main feeding artery was the ipsilateral lingual artery (LA) in 15 of the 20 examined tumors and the contralateral LA in the other 5. Ten cancers had only one feeding artery, and multiple feeding arteries were detected in the remaining 10. Tumors >4 cm (n = 9), those with extension to the contralateral side (n = 13), and those with extension to TEMs (n = 15) were supplied by significantly larger numbers of feeding arteries compared to tumors without these features (P = 0.01, 0.049, and 0.02, respectively). The frequency of feeding from the contralateral LA was 64 % (9/14) and 17 % (1/6) in tumors with and without extension to the contralateral side, respectively. Feeding from a facial artery (FA) was not detected in tumors ≤4 cm, while 5 of the 9 (56 %) tumors >4 cm were supplied by a FA (P = 0.01).ConclusionA careful search for feeding arteries is required, especially in large tumors with extension to the contralateral side or to TEMs.

  13. Peripheral Endothelial Function After Arterial Switch Operation for D-looped Transposition of the Great Arteries.

    Science.gov (United States)

    Sun, Heather Y; Stauffer, Katie Jo; Nourse, Susan E; Vu, Chau; Selamet Tierney, Elif Seda

    2017-06-01

    Coronary artery re-implantation during arterial switch operation in patients with D-looped transposition of the great arteries (D-TGA) can alter coronary arterial flow and increase shear stress, leading to local endothelial dysfunction, although prior studies have conflicting results. Endothelial pulse amplitude testing can predict coronary endothelial dysfunction by peripheral arterial testing. This study tested if, compared to healthy controls, patients with D-TGA after arterial switch operation had peripheral endothelial dysfunction. Patient inclusion criteria were (1) D-TGA after neonatal arterial switch operation; (2) age 9-29 years; (3) absence of known cardiovascular risk factors such as hypertension, diabetes, hypercholesterolemia, vascular disease, recurrent vasovagal syncope, and coronary artery disease; and (4) ability to comply with overnight fasting. Exclusion criteria included (1) body mass index ≥85th percentile, (2) use of medications affecting vascular tone, or (3) acute illness. We assessed endothelial function by endothelial pulse amplitude testing and compared the results to our previously published data in healthy controls (n = 57). We tested 20 D-TGA patients (16.4 ± 4.8 years old) who have undergone arterial switch operation at a median age of 5 days (0-61 days). Endothelial pulse amplitude testing indices were similar between patients with D-TGA and controls (1.78 ± 0.61 vs. 1.73 ± 0.54, p = 0.73).In our study population of children and young adults, there was no evidence of peripheral endothelial dysfunction in patients with D-TGA who have undergone arterial switch operation. Our results support the theory that coronary arterial wall thickening and abnormal vasodilation reported in these patients is a localized phenomenon and not reflective of overall atherosclerotic burden.

  14. Vascular Extracellular Matrix and Arterial Mechanics

    Science.gov (United States)

    WAGENSEIL, JESSICA E.; MECHAM, ROBERT P.

    2009-01-01

    An important factor in the transition from an open to a closed circulatory system was a change in vessel wall structure and composition that enabled the large arteries to store and release energy during the cardiac cycle. The component of the arterial wall in vertebrates that accounts for these properties is the elastic fiber network organized by medial smooth muscle. Beginning with the onset of pulsatile blood flow in the developing aorta, smooth muscle cells in the vessel wall produce a complex extracellular matrix (ECM) that will ultimately define the mechanical properties that are critical for proper function of the adult vascular system. This review discusses the structural ECM proteins in the vertebrate aortic wall and will explore how the choice of ECM components has changed through evolution as the cardiovascular system became more advanced and pulse pressure increased. By correlating vessel mechanics with physiological blood pressure across animal species and in mice with altered vessel compliance, we show that cardiac and vascular development are physiologically coupled, and we provide evidence for a universal elastic modulus that controls the parameters of ECM deposition in vessel wall development. We also discuss mechanical models that can be used to design better tissue-engineered vessels and to test the efficacy of clinical treatments. PMID:19584318

  15. Abdominal wall fat pad biopsy

    Science.gov (United States)

    Amyloidosis - abdominal wall fat pad biopsy; Abdominal wall biopsy; Biopsy - abdominal wall fat pad ... method of taking an abdominal wall fat pad biopsy . The health care provider cleans the skin on ...

  16. Segmentation features and structural organization of the intrapulmonary artery of the yak.

    Science.gov (United States)

    Zhou, Jinxing; Yu, Sijiu; He, Junfeng; Cui, Yan

    2013-11-01

    This study aims to systematically investigate intrapulmonary artery segmentation, blood vessel wall characteristics and structure organization, and the interrelation between intrapulmonary artery structure and plateau hypoxia adaptation in yak. The normal intrapulmonary artery structure of the yak had been studied using histological methods and transmission electron microscopy. The intrapulmonary artery of the yak was also examined using morphometric analysis and angiography. Results showed that the elastic intrapulmonary artery is divided into two types, namely, classical and transitional elastic segments. The muscular intrapulmonary artery is divided into three types, namely, transitional, classical muscular, and muscular arteriole segments. In the transitional elastic artery, elastic fibers and smooth muscles are linked through three models of ends, lateral branches, and branch tops. Two phenomena are possible for the transition from the elastic intrapulmonary artery to the muscular artery. One phenomenon postulates that a less elastic membrane is first increased and then suddenly decreased, and another supposes that the elastic membrane is gradually reduced and assembled in one to two layers before entering the transitional muscular artery. The smooth muscle of the intrapulmonary artery tunica media had more apophysis; it was physically connected with elastic membrane or fiber and composed of functionally resilient unit of the intrapulmonary arterial wall. Glycogenosomes increased in the muscular intrapulmonary artery smooth muscle cells. It exist one to two layers intact smooth muscle in intrapulmonary arteriole, the presence of intact smooth muscle in the intrapulmonary arteriole of the yak is a kind of structure adaptation to low-oxygen environment. Copyright © 2013 Wiley Periodicals, Inc.

  17. The Digital Evolution of Occupy Wall Street

    OpenAIRE

    Conover, Michael D.; Ferrara, Emilio; Menczer, Filippo; Flammini, Alessandro

    2013-01-01

    We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the movement's first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit participation ...

  18. The Interaction between Fluid Wall Shear Stress and Solid Circumferential Strain Affects Endothelial Gene Expression

    Science.gov (United States)

    Amaya, Ronny; Pierides, Alexis; Tarbell, John M.

    2015-01-01

    Endothelial cells lining the walls of blood vessels are exposed simultaneously to wall shear stress (WSS) and circumferential stress (CS) that can be characterized by the temporal phase angle between WSS and CS (stress phase angle – SPA). Regions of the circulation with highly asynchronous hemodynamics (SPA close to -180°) such as coronary arteries are associated with the development of pathological conditions such as atherosclerosis and intimal hyperplasia whereas more synchronous regions (SPA closer to 0°) are spared of disease. The present study evaluates endothelial cell gene expression of 42 atherosclerosis-related genes under asynchronous hemodynamics (SPA=-180 °) and synchronous hemodynamics (SPA=0 °). This study used a novel bioreactor to investigate the cellular response of bovine aortic endothelial cells (BAECS) exposed to a combination of pulsatile WSS and CS at SPA=0 or SPA=-180. Using a PCR array of 42 genes, we determined that BAECS exposed to non-reversing sinusoidal WSS (10±10 dyne/cm2) and CS (4 ± 4 %) over a 7 hour testing period displayed 17 genes that were up regulated by SPA = -180 °, most of them pro-atherogenic, including NFκB and other NFκB target genes. The up regulation of NFκB p50/p105 and p65 by SPA =-180° was confirmed by Western blots and immunofluorescence staining demonstrating the nuclear translocation of NFκB p50/p105 and p65. These data suggest that asynchronous hemodynamics (SPA=-180 °) can elicit proatherogenic responses in endothelial cells compared to synchronous hemodynamics without shear stress reversal, indicating that SPA may be an important parameter characterizing arterial susceptibility to disease. PMID:26147292

  19. The Interaction between Fluid Wall Shear Stress and Solid Circumferential Strain Affects Endothelial Gene Expression.

    Directory of Open Access Journals (Sweden)

    Ronny Amaya

    Full Text Available Endothelial cells lining the walls of blood vessels are exposed simultaneously to wall shear stress (WSS and circumferential stress (CS that can be characterized by the temporal phase angle between WSS and CS (stress phase angle - SPA. Regions of the circulation with highly asynchronous hemodynamics (SPA close to -180° such as coronary arteries are associated with the development of pathological conditions such as atherosclerosis and intimal hyperplasia whereas more synchronous regions (SPA closer to 0° are spared of disease. The present study evaluates endothelial cell gene expression of 42 atherosclerosis-related genes under asynchronous hemodynamics (SPA=-180 ° and synchronous hemodynamics (SPA=0 °. This study used a novel bioreactor to investigate the cellular response of bovine aortic endothelial cells (BAECS exposed to a combination of pulsatile WSS and CS at SPA=0 or SPA=-180. Using a PCR array of 42 genes, we determined that BAECS exposed to non-reversing sinusoidal WSS (10±10 dyne/cm2 and CS (4 ± 4% over a 7 hour testing period displayed 17 genes that were up regulated by SPA = -180 °, most of them pro-atherogenic, including NFκB and other NFκB target genes. The up regulation of NFκB p50/p105 and p65 by SPA =-180° was confirmed by Western blots and immunofluorescence staining demonstrating the nuclear translocation of NFκB p50/p105 and p65. These data suggest that asynchronous hemodynamics (SPA=-180 ° can elicit proatherogenic responses in endothelial cells compared to synchronous hemodynamics without shear stress reversal, indicating that SPA may be an important parameter characterizing arterial susceptibility to disease.

  20. KIR channels tune electrical communication in cerebral arteries

    DEFF Research Database (Denmark)

    Sancho, Maria; Samson, Nina C; Hald, Bjorn O

    2017-01-01

    The conducted vasomotor response reflects electrical communication in the arterial wall and the distance signals spread is regulated by three factors including resident ion channels. This study defined the role of inward-rectifying K(+) channels (KIR) in governing electrical communication along h...... and the increased feedback arising from voltage-dependent-K(+) channels. In summary, this study shows that two KIR populations work collaboratively to govern electrical communication and the spread of vasomotor responses along cerebral arteries.......The conducted vasomotor response reflects electrical communication in the arterial wall and the distance signals spread is regulated by three factors including resident ion channels. This study defined the role of inward-rectifying K(+) channels (KIR) in governing electrical communication along...... hamster cerebral arteries. Focal KCl application induced a vasoconstriction that conducted robustly, indicative of electrical communication among cells. Inhibiting dominant K(+) conductances had no attenuating effect, the exception being Ba(2+) blockade of KIR Electrophysiology and Q-PCR analysis...

  1. Green walls in Vancouver

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, R. [Sharp and Diamond Landscape Architecture Inc., Vancouver, BC (Canada)

    2007-07-01

    With the renewed interest in design for microclimate control and energy conservation, many cities are implementing clean air initiatives and sustainable planning policies to mitigate the effects of urban climate and the urban heat island effect. Green roofs, sky courts and green walls must be thoughtfully designed to withstand severe conditions such as moisture stress, extremes in temperature, tropical storms and strong desiccating winds. This paper focused on the installation of green wall systems. There are 2 general types of green walls systems, namely facade greening and living walls. Green facades are trellis systems where climbing plants can grow vertically without attaching to the surface of the building. Living walls are part of a building envelope system where plants are actually planted and grown in a wall system. A modular G-SKY Green Wall Panel was installed at the Aquaquest Learning Centre at the Vancouver Aquarium in Stanley Park in September 2006. This green wall panel, which was originally developed in Japan, incorporates many innovative features in the building envelope. It provides an exterior wall covered with 8 species of plants native to the Coastal Temperate Rain Forest. The living wall is irrigated by rainwater collected from the roof, stored in an underground cistern and fed through a drip irrigation system. From a habitat perspective, the building imitates an escarpment. Installation, support systems, irrigation, replacement of modules and maintenance are included in the complete wall system. Living walls reduce the surface temperature of buildings by as much as 10 degrees C when covered with vegetation and a growing medium. The project team is anticipating LEED gold certification under the United States-Canada Green Building Council. It was concluded that this technology of vegetated building envelopes is applicable for acoustical control at airports, biofiltration of indoor air, greywater treatment, and urban agriculture and vertical

  2. Automated carotid artery intima layer regional segmentation

    Science.gov (United States)

    Meiburger, Kristen M.; Molinari, Filippo; Rajendra Acharya, U.; Saba, Luca; Rodrigues, Paulo; Liboni, William; Nicolaides, Andrew; Suri, Jasjit S.

    2011-07-01

    Evaluation of the carotid artery wall is essential for the assessment of a patient's cardiovascular risk or for the diagnosis of cardiovascular pathologies. This paper presents a new, completely user-independent algorithm called carotid artery intima layer regional segmentation (CAILRS, a class of AtheroEdge™ systems), which automatically segments the intima layer of the far wall of the carotid ultrasound artery based on mean shift classification applied to the far wall. Further, the system extracts the lumen-intima and media-adventitia borders in the far wall of the carotid artery. Our new system is characterized and validated by comparing CAILRS borders with the manual tracings carried out by experts. The new technique is also benchmarked with a semi-automatic technique based on a first-order absolute moment edge operator (FOAM) and compared to our previous edge-based automated methods such as CALEX (Molinari et al 2010 J. Ultrasound Med. 29 399-418, 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CULEX (Delsanto et al 2007 IEEE Trans. Instrum. Meas. 56 1265-74, Molinari et al 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CALSFOAM (Molinari et al Int. Angiol. (at press)), and CAUDLES-EF (Molinari et al J. Digit. Imaging (at press)). Our multi-institutional database consisted of 300 longitudinal B-mode carotid images. In comparison to semi-automated FOAM, CAILRS showed the IMT bias of -0.035 ± 0.186 mm while FOAM showed -0.016 ± 0.258 mm. Our IMT was slightly underestimated with respect to the ground truth IMT, but showed uniform behavior over the entire database. CAILRS outperformed all the four previous automated methods. The system's figure of merit was 95.6%, which was lower than that of the semi-automated method (98%), but higher than that of the other automated techniques.

  3. Automated carotid artery intima layer regional segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Meiburger, Kristen M; Molinari, Filippo [Biolab, Department of Electronics, Politecnico di Torino, Torino (Italy); Acharya, U Rajendra [Department of ECE, Ngee Ann Polytechnic (Singapore); Saba, Luca [Department of Radiology, A.O.U. di Cagliari, Cagliari (Italy); Rodrigues, Paulo [Department of Computer Science, Centro Universitario da FEI, Sao Paulo (Brazil); Liboni, William [Neurology Division, Gradenigo Hospital, Torino (Italy); Nicolaides, Andrew [Vascular Screening and Diagnostic Centre, London (United Kingdom); Suri, Jasjit S, E-mail: filippo.molinari@polito.it [Fellow AIMBE, CTO, Global Biomedical Technologies Inc., CA (United States)

    2011-07-07

    Evaluation of the carotid artery wall is essential for the assessment of a patient's cardiovascular risk or for the diagnosis of cardiovascular pathologies. This paper presents a new, completely user-independent algorithm called carotid artery intima layer regional segmentation (CAILRS, a class of AtheroEdge(TM) systems), which automatically segments the intima layer of the far wall of the carotid ultrasound artery based on mean shift classification applied to the far wall. Further, the system extracts the lumen-intima and media-adventitia borders in the far wall of the carotid artery. Our new system is characterized and validated by comparing CAILRS borders with the manual tracings carried out by experts. The new technique is also benchmarked with a semi-automatic technique based on a first-order absolute moment edge operator (FOAM) and compared to our previous edge-based automated methods such as CALEX (Molinari et al 2010 J. Ultrasound Med. 29 399-418, 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CULEX (Delsanto et al 2007 IEEE Trans. Instrum. Meas. 56 1265-74, Molinari et al 2010 IEEE Trans. Ultrason. Ferroelectr. Freq. Control 57 1112-24), CALSFOAM (Molinari et al Int. Angiol. (at press)), and CAUDLES-EF (Molinari et al J. Digit. Imaging (at press)). Our multi-institutional database consisted of 300 longitudinal B-mode carotid images. In comparison to semi-automated FOAM, CAILRS showed the IMT bias of -0.035 {+-} 0.186 mm while FOAM showed -0.016 {+-} 0.258 mm. Our IMT was slightly underestimated with respect to the ground truth IMT, but showed uniform behavior over the entire database. CAILRS outperformed all the four previous automated methods. The system's figure of merit was 95.6%, which was lower than that of the semi-automated method (98%), but higher than that of the other automated techniques.

  4. In vivo noninvasive method for measuring local wave velocity in femoral arteries of pig

    Science.gov (United States)

    Zhang, Xiaoming; Kinnick, Randall; Pislaru, Cristina; Fatemi, Mostafa; Greenleaf, James

    2005-09-01

    We have proposed generating a bending wave in the arterial wall using ultrasound radiation force and measuring the wave velocity along the arterial wall [Zhang et al., IEEE Trans. Ultrason. Ferroelectr. Freq. Control 52, 642-652 (2005)]. Here, we report the results of in vivo studies on pigs. The pig was anesthetized, and a micromanometer tip catheter was inserted into the femoral artery to measure luminal pressure. A water bath was created on the animal's groin to allow unimpeded access of the ultrasound beams to the femoral artery. The femoral artery was first located using a 13-MHz linear-array transducer. Then, a vibro-acoustography image was obtained to ensure precise positioning of the excitation force relative to the artery. The artery was excited by the force transducer and the resulting vibration of the arterial wall was measured by a sensing Doppler transceiver. Measured wave velocity was 3.1 m/s at 300 Hz. With this new method wave velocity over a distance of 5 mm, and therefore stiffness of arteries, can be measured locally and non-invasively. Measurement time is short in a few tens of milliseconds, which allows pressure dependence and pharmacological effect on the wall properties to be measured at different cardiac times.

  5. Bacteria of leg atheromatous arteries responsible for inflammation.

    Science.gov (United States)

    Olszewski, Waldemar Lech; Rutkowska, Joanna; Moscicka-Wesolowska, Maria; Swoboda-Kopec, Ewa; Stelmach, Ewa; Zaleska, Marzanna; Zagozda, Malgorzata

    2016-09-01

    Ischaemia of the lower limbs is frequently followed by inflammation and, in advanced cases, necrosis of peripheral tissues. Whether this is caused by arterial hypoperfusion only or by the presence of bacteria in the arterial walI as well remains unclear. The aim of the study was to prove the presence and source of bacteria in arterial specimens and evaluate their chemotactic properties resulting in the formation of periarterial cellular infiltrates. Bacterial culture and testing for 16sRNA were performed in fragments of popliteal artery harvested from amputated limbs. Carotid artery plaques served as controls. Fragments of arteries were transplanted into scid mice to evaluate their chemotactic activity for macrophages. a) higher prevalence of isolates and 16sRNA in atherosclerotic popliteal than carotid arteries, b) high density of plaque and periarterial infiltrates and mRNA level for pro-inflammatory cytokines in popliteal arteries, c) prevalent microbes were Staphylococcus aureus, S. epidermidis and Enterococci, d) foot skin and arterial bacterial phenotypes and DNA revealed evident similarities, and e) more intensive mouse macrophage accumulation in popliteal than carotid implants into scid mice. The presence of bacteria in the lower limb arterial wall was documented. They may predispose to inflammation secondary to ischaemic changes.

  6. Effect of pulsatile swirling flow on stenosed arterial blood flow.

    Science.gov (United States)

    Ha, Hojin; Lee, Sang Joon

    2014-09-01

    The existence of swirling flow phenomena is frequently observed in arterial vessels, but information on the fluid-dynamic roles of swirling flow is still lacking. In this study, the effects of pulsatile swirling inlet flows with various swirling intensities on the flow field in a stenosis model are experimentally investigated using a particle image velocimetry velocity field measurement technique. A pulsatile pump provides cyclic pulsating inlet flow and spiral inserts with two different helical pitches (10D and 10/3D) induce swirling flow in the stenosed channel. Results show that the pulsatile swirling flow has various beneficial effects by reducing the negative wall shear stress, the oscillatory shear index, and the flow reverse coefficient at the post-stenosis channel. Temporal variations of vorticity fields show that the short propagation length of the jet flow and the early breakout of turbulent flow are initiated as the swirling flow disturbs the symmetric development of the shear layer. In addition, the overall energy dissipation rate of the flow is suppressed by the swirling component of the flow. The results will be helpful for elucidating the hemodynamic characteristics of atherosclerosis and discovering better diagnostic procedures and clinical treatments. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  7. Cardiac causes of pulmonary arterial hypertension: assessment with multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, Edward T.D.; Gopalan, Deepa; Agrawal, S.K.B. [Papworth Hospital, Cambridge (United Kingdom); Screaton, Nicholas J. [Papworth Hospital, Cambridge (United Kingdom); Papworth Hospital NHS Trust, Diagnostic Centre, Department of Radiology, Papworth Everard, Cambridgeshire (United Kingdom)

    2009-11-15

    The causes of pulmonary arterial hypertension (PAH) are diverse and include multiple congenital and acquired cardiac diseases as well as diseases primarily affecting the pulmonary vasculature, lung, pleura and chest wall. The traditional role of CT in evaluating PAH includes assessment of pulmonary vasculature and lung parenchyma with limited assessment of the heart. Advances in multidetector CT technology with improved spatial and temporal resolution now permit accurate delineation of cardiac morphology. CT pulmonary angiography (CTPA) is widely utilised in the workup of patients with suspected pulmonary vascular disease and can identify both pulmonary and cardiac causes. As the initial presentation for CTPA is often precipitated by nonspecific, unexplained symptoms and therefore undertaken by a general radiologist, it is important that a systematic approach to the interpretation of these studies, including cardiac evaluation, is routinely adopted. This paper reviews the CT evaluation in pulmonary hypertension with a particular focus on the cardiac causes, their subclassification into congenital systemic to pulmonary shunts and secondary to left heart disease, and their imaging features. It emphasises the use of a systematic approach to interpretation of CTPA examinations both in patients with known PAH and those with previously unsuspected disease. (orig.)

  8. Automated quantification of bronchiectasis, airway wall thickening and lumen tapering in chest CT

    DEFF Research Database (Denmark)

    Perez-Rovira, Adria; Kuo, Wieying; Petersen, Jens

    Purpose: To automatically quantify airway structural properties visualised on CT in children with cystic fibrosis (CF) and controls, including: bronchiectasis, airway wall thickening, and lumen tapering. Methods and materials: The 3D surface of the airway lumen, outer wall, and bronchial arteries...

  9. Anomalous left coronary artery from the pulmonary artery

    Science.gov (United States)

    ... of the left coronary artery arising from the pulmonary artery; ALCAPA; ALCAPA syndrome; Bland-White-Garland syndrome; ... children with ALCAPA, the LCA originates from the pulmonary artery. The pulmonary artery is the major blood ...

  10. Low level termination of external carotid artery and its clinical significance: A case report

    Directory of Open Access Journals (Sweden)

    Surekha Devadasa Shetty

    2015-09-01

    Full Text Available The external carotid arterial system is a complex vascular system providing nourishment to the territorial areas of the head and neck. The branches of the external carotid artery are the key landmarks for adequate exposure and appropriate placement of cross-clamps on the carotid arteries during carotid endarterectomy. Knowledge of anatomical variation of the external carotid artery is important in head and neck surgeries. Variations in the branching pattern of the external carotid artery are well known and documented. We report a rare case of low-level termination of the external carotid artery. It terminated by dividing into maxillary and superficial temporal arteries deep into the posterior belly of the digastric muscle, one inch below the angle of the mandible. The occipital and posterior auricular arteries arose from a common trunk given off by the external carotid artery. [Arch Clin Exp Surg 2015; 4(3.000: 160-163

  11. A viscoelastic fluid-structure interaction model for carotid arteries under pulsatile flow.

    Science.gov (United States)

    Wang, Zhongjie; Wood, Nigel B; Xu, Xiao Yun

    2015-05-01

    In this study, a fluid-structure interaction model (FSI) incorporating viscoelastic wall behaviour is developed and applied to an idealized model of the carotid artery under pulsatile flow. The shear and bulk moduli of the arterial wall are described by Prony series, where the parameters can be derived from in vivo measurements. The aim is to develop a fully coupled FSI model that can be applied to realistic arterial geometries with normal or pathological viscoelastic wall behaviour. Comparisons between the numerical and analytical solutions for wall displacements demonstrate that the coupled model is capable of predicting the viscoelastic behaviour of carotid arteries. Comparisons are also made between the solid only and FSI viscoelastic models, and the results suggest that the difference in radial displacement between the two models is negligible. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Propagation of dissection in a residually-stressed artery model.

    Science.gov (United States)

    Wang, Lei; Roper, Steven M; Hill, Nicholas A; Luo, Xiaoyu

    2017-02-01

    This paper studies dissection propagation subject to internal pressure in a residually-stressed two-layer arterial model. The artery is assumed to be infinitely long, and the resultant plane strain problem is solved using the extended finite element method. The arterial layers are modelled using the anisotropic hyperelastic Holzapfel-Gasser-Ogden model, and the tissue damage due to tear propagation is described using a linear cohesive traction-separation law. Residual stress in the arterial wall is determined by an opening angle [Formula: see text] in a stress-free configuration. An initial tear is introduced within the artery which is subject to internal pressure. Quasi-static solutions are computed to determine the critical value of the pressure, at which the dissection starts to propagate. Our model shows that the dissection tends to propagate radially outwards. Interestingly, the critical pressure is higher for both very short and very long tears. The simulations also reveal that the inner wall buckles for longer tears, which is supported by clinical CT scans. In all simulated cases, the critical pressure is found to increase with the opening angle. In other words, residual stress acts to protect the artery against tear propagation. The effect of residual stress is more prominent when a tear is of intermediate length ([Formula: see text]90[Formula: see text] arc length). There is an intricate balance between tear length, wall buckling, fibre orientation, and residual stress that determines the tear propagation.

  13. Origin of axial prestretch and residual stress in arteries.

    Science.gov (United States)

    Cardamone, L; Valentín, A; Eberth, J F; Humphrey, J D

    2009-12-01

    The structural protein elastin endows large arteries with unique biological functionality and mechanical integrity, hence its disorganization, fragmentation, or degradation can have important consequences on the progression and treatment of vascular diseases. There is, therefore, a need in arterial mechanics to move from materially uniform, phenomenological, constitutive relations for the wall to those that account for separate contributions of the primary structural constituents: elastin, fibrillar collagens, smooth muscle, and amorphous matrix. In this paper, we employ a recently proposed constrained mixture model of the arterial wall and show that prestretched elastin contributes significantly to both the retraction of arteries that is observed upon transection and the opening angle that follows the introduction of a radial cut in an unloaded segment. We also show that the transmural distributions of elastin and collagen, compressive stiffness of collagen, and smooth muscle tone play complementary roles. Axial prestresses and residual stresses in arteries contribute to the homeostatic state of stress in vivo as well as adaptations to perturbed loads, disease, or injury. Understanding better the development of and changes in wall stress due to individual extracellular matrix constituents thus promises to provide considerable clinically important insight into arterial health and disease.

  14. Origin of Axial Prestretch and Residual Stress in Arteries*

    Science.gov (United States)

    Cardamone, L.; Valentin, A.; Eberth, J.F.; Humphrey, J.D.

    2009-01-01

    The structural protein elastin endows large arteries with unique biological functionality and mechanical integrity, hence its disorganization, fragmentation, or degradation can have important consequences on the progression and treatment of vascular diseases. There is, therefore, a need in arterial mechanics to move from materially uniform, phenomenological, constitutive relations for the wall to those that account for separate contributions of the primary structural constituents: elastin, fibrillar collagens, smooth muscle, and amorphous matrix. In this paper, we employ a recently proposed constrained mixture model of the arterial wall and show that prestretched elastin contributes significantly to both the retraction of arteries that is observed upon transection and the opening angle that follows the introduction of a radial cut in an unloaded segment. We also show that the transmural distributions of elastin and collagen, compressive stiffness of collagen, and smooth muscle tone play complementary roles. Axial prestresses and residual stresses in arteries contribute to the homeostatic state of stress in vivo as well as adaptations to perturbed loads, disease, or injury. Understanding better the development of and changes in wall stress due to individual extracellular matrix constituents thus promises to provide considerable clinically important insight into arterial health and disease. PMID:19123012

  15. Coronary Artery Circumferential Stress: Departure from Laplace Expectations with Aging

    Directory of Open Access Journals (Sweden)

    Richard E Tracy

    2009-01-01

    Full Text Available Normal, youthful arteries generally maintain constant radius/wall thickness ratios, with the relationship being described by the Laplace Law. Whether this relationship is maintained during aging is unclear. This study first examines the Laplace relationships in postmortem coronary arteries using a novel method to correct measurements for postmortem artifacts, uses data from the literature to provide preliminary validation, and then describes histology associated with low circumferential stress. Measurements of radius and wall thickness, taken at sites free from atheromas, were used with national population estimates of age-, gender-, and race-specific blood pressure data to calculate average circumferential stress within demographic groups. The estimated circumferential stress at ages 55-74 years was about half that at ages 18-24 years because of a disproportionate increase of wall thickness relative to artery radius at older ages, violating the expected relationships described by the Laplace Law. Arteries with low circumferential stress (estimated at sites distant from atherosclerosis had more necrotic atheromas than arteries with high stress. At sites with low stress and intimal thickening, smooth muscle cells (SMCs were spread apart, thereby diminishing their density within both the intima and media. Thus, older arteries displayed both low circumferential stress and abundant matrix of low cellularity microscopically. Such changes might alter SMC-matrix interactions.

  16. Supersymmetric domain walls

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Kleinschmidt, Axel; Riccioni, Fabio

    2012-01-01

    We classify the half-supersymmetric "domain walls," i.e., branes of codimension one, in toroidally compactified IIA/IIB string theory and show to which gauged supergravity theory each of these domain walls belong. We use as input the requirement of supersymmetric Wess-Zumino terms, the properties of

  17. Thin Wall Iron Castings

    Energy Technology Data Exchange (ETDEWEB)

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka

    2001-10-31

    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  18. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik

    2010-01-01

    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...

  19. International Divider Walls

    NARCIS (Netherlands)

    Kruis, A.; Sneller, A.C.W.(L.)

    2013-01-01

    The subject of this teaching case is the Enterprise Resource Planning (ERP) system implementation at International Divider Walls, the world market leader in design, production, and sales of divider walls. The implementation in one of the divisions of this multinational company had been successful,

  20. Separate origin of the main components of the left coronary artery in Syrian hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Durán, A C; Arqué, J M; Fernández, B; Fernández, M C; Fernández-Gallego, T; Sans-Coma, V

    2007-08-01

    This study describes a rare congenital coronary artery anomaly in the Syrian hamster; namely, the separate origin of the obtuse marginal and left circumflex arteries which are the main components of the left coronary artery. The hearts of nine affected animals were examined by means of a corrosion-cast technique and histology. The hamsters belonged to a laboratory inbred family with a high incidence of coronary artery anomalies and bicuspid aortic valve. The aortic valve was tricuspid in three hamsters and bicuspid in the other six hamsters. In all cases, the right coronary artery was normal, whereas the left coronary artery main trunk was absent. The present anomalous coronary artery patterns could be classified into two main entities: (i) ectopic origin of the obtuse marginal artery from the right aortic sinus or from the right coronary artery, with the left circumflex artery arising from the left side of the aortic valve; and (ii) ectopic origin of both the obtuse marginal artery from the right aortic sinus or from the right coronary artery and left circumflex artery from the dorsal aortic sinus. In all cases, the obtuse marginal artery coursed to the right side of the heart through the ventral wall of the right ventricular outflow tract. When the left circumflex artery arose from the dorsal aortic sinus, it formed an acute angle with the aortic wall. This report seems to be the first to describe the separate origin of the main components of the left coronary artery in a non-human mammalian species. In man, the congenital coronary artery and aortic valve defects reported herein may entail the risk of clinical complications. However, none of the affected hamsters showed signs of disease.

  1. Modeling Effects of Axial Extension on Arterial Growth and Remodeling

    OpenAIRE

    Valentín, A.; Humphrey, J. D.

    2009-01-01

    Diverse mechanical perturbations elicit arterial growth and remodeling responses that appear to optimize structure and function so as to achieve mechanical homeostasis. For example, it is well known that functional adaptations to sustained changes in transmural pressure and blood flow primarily affect wall thickness and caliber to restore circumferential and wall shear stresses toward normal. More recently, however, it has been shown that changes in axial extension similarly prompt dramatic c...

  2. Bilateral renal artery variation

    OpenAIRE

    Üçerler, Hülya; Üzüm, Yusuf; İkiz, Z. Aslı Aktan

    2015-01-01

    Each kidney is supplied by a single renal artery, although renal artery variations are common. Variations of the renal arteryhave become important with the increasing number of renal transplantations. Numerous studies describe variations in renalartery anatomy. Especially the left renal artery is among the most critical arterial variations, because it is the referred side forresecting the donor kidney. During routine dissection in a formalin fixed male cadaver, we have found a bilateral renal...

  3. Implementation of variable segments to model the arterial system using electromechanical analogy

    Science.gov (United States)

    Borik, Stefan; Cap, Ivo; Babusiak, Branko; Capova, Klara

    2017-05-01

    The article deals with the design of an electrical model of variable segments of a non-symmetrical tree of small arteries This model can be used to simulate the blood pressure and flow. Peripheral arterial resistance changes are modelled by an exponentially dependent resistor. By modulating the capacitor value, we can model the arterial wall properties which depend on the arterial pressure. Simulations are performed in which vasoconstriction and vasodilation were modelled by varying the transmural pressure. As a result, we can observe the changes in the blood pressure for each arterial generation.

  4. Echocardiographic presentation of anomalous origin of the left coronary artery from the pulmonary artery.

    Science.gov (United States)

    Silverman, Norman H

    2015-12-01

    In the 1970s, diagnosing anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) was often uncertain using imaging alone; however, with the advances in high-frequency transducers, advanced image processing, and other ultrasound modalities such as Doppler colour flow imaging, tissue Doppler imaging, and speckle tracking to asses regional wall motion abnormalities, modern echocardiography now permits accurate diagnosis of ALCAPA with greater certainty. Although many consider ultrasound to be the only imaging test necessary if there is a question as to the diagnosis, other imaging modalities such as MRI, CT, and cardiac catheterisation with angiography remain valuable complementary tests, especially in older patients.

  5. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth

    OpenAIRE

    Jean-Claude Mollet; Christelle Leroux; Flavien Dardelle; Arnaud Lehner

    2013-01-01

    The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with...

  6. Pulsatile blood flow in elastic artery with model aneurysm

    Science.gov (United States)

    Nikolov, N.; Radev, St.; Tabakova, S.

    2017-11-01

    The mathematical modeling and numerical simulations are expected to play an important role to predict the genesis of different cardiovascular diseases, such as the formation and rupture of aneurysms. In the present work, the numerical solutions of the oscillatory blood flow are constructed for an elastic artery with a model aneurysm by use of the software ANSYS. It is observed that the artery elastic strain behaves in a different way: stably or unstably depending on the different combinations between the flow parameter (outlet pressure) and the elastic modulus of the artery wall.

  7. Artery Bypass Grafting

    African Journals Online (AJOL)

    Unknown

    nary artery disease (CAD) was coronary artery bypass graft (CAB G) using a segment of saphenous vein interposed between the ascend- ing aorta and the coronary artery distal to the obstructing lesion. This was performed by David Sabiston of Duke University in 1962. With the use of the recently developed technique of ...

  8. Carotid artery surgery - slideshow

    Science.gov (United States)

    ... right- and left-internal carotid arteries, and the right- and left-external carotid arteries. The carotid arteries deliver oxygen-rich blood from the heart to both the head and brain. Review Date 6/1/2015 Updated by: Daniel ...

  9. Solar Walls in tsbi3

    DEFF Research Database (Denmark)

    Wittchen, Kim Bjarne

    tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building....... This version, C, of tsbi3 is capable of simulating five types of solar walls say: mass-walls, Trombe-walls, double Trombe-walls, internally ventilated walls and solar walls for preheating ventilation air. The user's guide gives a description of the capabilities and how to simulate solar walls in tsbi3....

  10. Alveolar Antral Artery: Review of Surgical Techniques Involving this Anatomic Structure

    Directory of Open Access Journals (Sweden)

    Amin Rahpeyma

    2014-04-01

    Full Text Available Introduction: The horizontal bony canal in the lateral maxillary wall is the site of anastomosis between the arterial branches from the posterior superior alveolar artery (PSAa and the infraorbital artery. This anatomic structure is known as the ‘alveolar antral artery’.   Materials and Methods: We performed a literature review. The anatomic location of the alveolar antral artery in the lateral maxillary sinus wall was researched and its importance in surgical procedures routinely performed on this bony wall discussed.   Results: This artery can be accidentally involved during surgical procedures on the lateral maxillary sinus wall, such as open sinus lift surgery, horizontal osteotomy of the maxilla, Le Fort I fracture treatment, and Caldwell-Luc surgeries.   Conclusion: The alveolar antral artery is an important anatomic structure in the lateral maxillary sinus wall. A preoperative cone beam computed tomography (CBCT scan can be used as a good diagnostic procedure to reduce surgical complications in suspected cases as well as conditions that may involve this artery

  11. Non-arterial assessment of blood gas status in patients with chronic pulmonary disease.

    Science.gov (United States)

    Elborn, J S; Finch, M B; Stanford, C F

    1991-10-01

    Assessment of blood gas status is important in the management of patients with chronic pulmonary disease. Arterial puncture is often painful and may damage the arterial wall. Measurement of oxygen saturation by transcutaneous oximetry offers a non-invasive alternative to arterial methods but does not allow assessment of partial pressure of carbon dioxide. We have examined the value of oximetry and dorsal hand venous carbon dioxide as an alternative to arterial puncture. Transcutaneous oxygen saturation correlated with arterial oxygen saturation (r = 0.76, p less than 0.001) with an error of 2.1% and dorsal hand venous carbon dioxide tension correlated with the arterial tension (r = 0.84, p less than 0.001) with an error of 8%. Changes in oximetric oxygen saturation and venous carbon dioxide tension following oxygen therapy reflected arterial values. Assessment of blood gas status using oximetry and dorsal hand venous carbon dioxide tension is a useful alternative to arterial puncture.

  12. Computational modeling of hypertensive growth in the human carotid artery

    Science.gov (United States)

    Sáez, Pablo; Peña, Estefania; Martínez, Miguel Angel; Kuhl, Ellen

    2014-06-01

    Arterial hypertension is a chronic medical condition associated with an elevated blood pressure. Chronic arterial hypertension initiates a series of events, which are known to collectively initiate arterial wall thickening. However, the correlation between macrostructural mechanical loading, microstructural cellular changes, and macrostructural adaptation remains unclear. Here, we present a microstructurally motivated computational model for chronic arterial hypertension through smooth muscle cell growth. To model growth, we adopt a classical concept based on the multiplicative decomposition of the deformation gradient into an elastic part and a growth part. Motivated by clinical observations, we assume that the driving force for growth is the stretch sensed by the smooth muscle cells. We embed our model into a finite element framework, where growth is stored locally as an internal variable. First, to demonstrate the features of our model, we investigate the effects of hypertensive growth in a real human carotid artery. Our results agree nicely with experimental data reported in the literature both qualitatively and quantitatively.

  13. Spontaneous renal artery dissection.

    Science.gov (United States)

    John, Santhosh G; Pillai, Unnikrishnan; Vaidyan, Philip B; Ishiyama, Takaaki

    2010-01-01

    Isolated spontaneous dissection of renal arteries or its branches are extremely rare. Most cases of renal artery dissection are associated with underlying pathology of the renal arteries. We report a case of spontaneous dissection of the left main renal artery and infarction of the left kidney with positive antiphospholipid antibody. Extensive work up of the patient including imaging studies confirmed the diagnosis of SRAD. Antiphospholipid antibodies may have a role in the pathogenesis of arterial dissection by causing endothelial dysfunction. This is a first literature report.

  14. Effects of Renal Denervation on Renal Artery Function in Humans: Preliminary Study.

    Directory of Open Access Journals (Sweden)

    Adelina Doltra

    Full Text Available To study the effects of RD on renal artery wall function non-invasively using magnetic resonance.32 patients undergoing RD were included. A 3.0 Tesla magnetic resonance of the renal arteries was performed before RD and after 6-month. We quantified the vessel sharpness of both renal arteries using a quantitative analysis tool (Soap-Bubble®. In 17 patients we assessed the maximal and minimal cross-sectional area of both arteries, peak velocity, mean flow, and renal artery distensibility. In a subset of patients wall shear stress was assessed with computational flow dynamics. Neither renal artery sharpness nor renal artery distensibility differed significantly. A significant increase in minimal and maximal areas (by 25.3%, p = 0.008, and 24.6%, p = 0.007, respectively, peak velocity (by 16.9%, p = 0.021, and mean flow (by 22.4%, p = 0.007 was observed after RD. Wall shear stress significantly decreased (by 25%, p = 0.029. These effects were observed in blood pressure responders and non-responders.RD is not associated with adverse effects at renal artery level, and leads to an increase in cross-sectional areas, velocity and flow and a decrease in wall shear stress.

  15. Saline flush during excimer laser angioplasty: short and long term effects in the rabbit femoral artery

    NARCIS (Netherlands)

    van Leeuwen, T. G.; Velema, E.; Pasterkamp, G.; Post, M. J.; Borst, C.

    1998-01-01

    BACKGROUND AND OBJECTIVE: In this study, the effect of flushing saline on arterial wall damage (medial ruptures and necrosis), intimal hyperplasia, and arterial remodeling was determined. During excimer laser coronary angioplasty saline is flushed to reduce the size of explosive water vapor bubbles

  16. Acute Anterior Myocardial Infarction Accompanied by Acute Inferior Myocardial Infarction: A Very Rare Coronary Artery Anomaly

    Directory of Open Access Journals (Sweden)

    Y. Alsancak

    2015-01-01

    Full Text Available Coronary artery anomalies are rare and mostly silent in clinical practice. First manifestation of this congenital abnormality can be devastating as syncope, acute coronary syndrome, and sudden cardiac death. Herein we report a case with coronary artery anomaly complicated with ST segment myocardial infarction in both inferior and anterior walls simultaneously diagnosed during primary percutaneous coronary intervention.

  17. Right iliac arterial aneurysm in a 4-year-old girl who does not have a right external iliac artery.

    Science.gov (United States)

    Lee, Jeong-Hwan; Oh, Chaeyoun; Youn, Joong Kee; Han, Ji-Won; Kim, Hyun-Young; Jung, Sung-Eun

    2016-11-01

    Pediatric arterial aneurysm is rare disease. Among them, idiopathic-congenital arterial aneurysm is extremely rare. This is a case report of right common iliac artery idiopathic aneurysm with absence of right external iliac artery. A 4-year-old girl who had been complaining of intermittent abdominal pain since 2 years prior presented with a right lower abdominal mass that had been palpable since 6 months prior. Abdominal CT revealed a 5.2 cm × 4.5 cm × 5.1 cm, right-sided, partially thrombosed, saccular, iliac artery aneurysm. She underwent to operation, aneurismal resection. A pathological examination confirmed that it was a true aneurysm, considering that all layers of the vascular wall were stretched with no deficit. The patient was discharged 3 days after the surgery without any complication. Five months passed since the surgery, and the patient is doing well without any abdominal or leg pain.

  18. Log-layer mismatch and modeling of the fluctuating wall stress in wall-modeled large-eddy simulations

    Science.gov (United States)

    Yang, Xiang I. A.; Park, George Ilhwan; Moin, Parviz

    2017-10-01

    Log-layer mismatch refers to a chronic problem found in wall-modeled large-eddy simulation (WMLES) or detached-eddy simulation, where the modeled wall-shear stress deviates from the true one by approximately 15 % . Many efforts have been made to resolve this mismatch. The often-used fixes, which are generally ad hoc, include modifying subgrid-scale stress models, adding a stochastic forcing, and moving the LES-wall-model matching location away from the wall. An analysis motivated by the integral wall-model formalism suggests that log-layer mismatch is resolved by the built-in physics-based temporal filtering. In this work we investigate in detail the effects of local filtering on log-layer mismatch. We show that both local temporal filtering and local wall-parallel filtering resolve log-layer mismatch without moving the LES-wall-model matching location away from the wall. Additionally, we look into the momentum balance in the near-wall region to provide an alternative explanation of how LLM occurs, which does not necessarily rely on the numerical-error argument. While filtering resolves log-layer mismatch, the quality of the wall-shear stress fluctuations predicted by WMLES does not improve with our remedy. The wall-shear stress fluctuations are highly underpredicted due to the implied use of LES filtering. However, good agreement can be found when the WMLES data are compared to the direct numerical simulation data filtered at the corresponding WMLES resolutions.

  19. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik

    2010-01-01

    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding...... is reduced. To investigate the possibilities, full-size wall elements with wooden cladding and different cavity design, type of cladding and type of wind barrier were exposed to natural climate on the outside and to a humid indoor climate on the inside. During the exposure period parts of the vapour barrier...

  20. [Alterations in arterial compliance of dyslipidemic patients].

    Science.gov (United States)

    Clara, Fernando Mario; Corral, Pablo; Blanco, Gustavo Hector; Scandurra, Adriana Graciela; Meschino, Gustavo Javier

    2015-01-01

    We studied the alteration on the distensibility of the arterial walls caused by dyslipidemia LDLc dependent, along the decades of life, by means of a study of the radial artery pulse wave. We made an analysis of the radial artery pulse wave records acquired by means a movement displacement sensor, placed on radial palpation area. We recruited 100 dyslipidemic men without other cardiovascular risk factors, between the 3rd and the 6th decade. We identified the reflected wave in the records and we computed the augmentation index in order to quantify its amplitude and position. This index is useful to assess the endothelial dysfunction. Besides, we defined a velocity coefficient as the ratio between the size of the individuals and the delay time between the peak of the systolic wave and the arrival of the reflected wave. Results were compared against those obtained in a group of 161 healthy volunteers. We found that dyslipidemic patients presented augmentation index values similar to controls until the fourth decade, increasing thereafter with significant differences only in the 6th decade. No significant differences were found in the velocity index in any of the ages studied. We conclude that alterations produced by dyslipidemia take decades to manifest, and they begin affecting the mechanism of vasodilation of distal arteries with highest proportion of smooth muscle, without altering the proximal conduit arteries with more elastin content. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  1. Coagulation and the vessel wall in thrombosis and atherosclerosis.

    Science.gov (United States)

    Kleinegris, Marie-Claire; Ten Cate-Hoek, Arina J; Ten Cate, Hugo

    2012-01-01

    The blood coagulation system is a key survival mechanism that has developed to protect man against lethal bleeding. A second function of blood coagulation is its close interaction with immunity. The immune-mediated coagulation responses may broadly be regarded as an element of response to injury. Pathological coagulation responses, including thromboembolism and disseminated intravascular coagulation (DIC), could therefore be regarded as excessive immune responses to a vessel wall injury. Virchow's triad, which comprises changes in the components of the blood, the state of the vessel wall, and the blood flow, was originally proposed for venous thrombosis. However, lately it appears that the same principles can be applied to arterial thrombosis and even DIC. It has even been postulated that all forms of thrombosis may be part of a continuous spectrum of the same disease. Over the past few years, an accumulation of evidence has shown that the etiopathogenetic mechanisms behind venous and arterial thrombosis are quite similar. The traditional elements of Virchow's triad are found to apply to both arterial and venous thrombosis. Yet, nowadays more emphasis is placed on the vessel wall and vascular bed specificity and the interaction with inflammation and hypercoagulability. This narrative review will discuss recent advances in research on the possible interactions between coagulation, the vascular endothelium, and atherosclerosis as well as the consequences of such interactions for venous and arterial thrombosis.

  2. Plasticity of endothelial cells during arterial-venous differentiation in the avian embryo.

    Science.gov (United States)

    Moyon, D; Pardanaud, L; Yuan, L; Bréant, C; Eichmann, A

    2001-09-01

    Remodeling of the primary vascular system of the embryo into arteries and veins has long been thought to depend largely on the influence of hemodynamic forces. This view was recently challenged by the discovery of several molecules specifically expressed by arterial or venous endothelial cells. We here analysed the expression of neuropilin-1 and TIE2, two transmembrane receptors known to play a role in vascular development. In birds, neuropilin-1 was expressed by arterial endothelium and wall cells, but absent from veins. TIE2 was strongly expressed in embryonic veins, but only weakly transcribed in most arteries. To examine whether endothelial cells are committed to an arterial or venous fate once they express these specific receptors, we constructed quail-chick chimeras. The dorsal aorta, carotid artery and the cardinal and jugular veins were isolated together with the vessel wall from quail embryos between embryonic day 2 to 15 and grafted into the coelom of chick hosts. Until embryonic day 7, all grafts yielded endothelial cells that colonized both host arteries and veins. After embryonic day 7, endothelial plasticity was progressively lost and from embryonic day 11 grafts of arteries yielded endothelial cells that colonized only chick arteries and rarely reached the host veins, while grafts of jugular veins colonized mainly host veins. When isolated from the vessel wall, quail aortic endothelial cells from embryonic day 11 embryos were able to colonize both host arteries and veins. Our results show that despite the expression of arterial or venous markers the endothelium remains plastic with regard to arterial-venous differentiation until late in embryonic development and point to a role for the vessel wall in endothelial plasticity and vessel identity.

  3. Energetic and spatial constraints of arterial networks

    Directory of Open Access Journals (Sweden)

    Sandro Rossitti

    1995-06-01

    Full Text Available The principle of minimum work (PMW is a parametric optimization model for the growth and adaptation of arterial trees. A balance between energy dissipation due to frictional resistance of laminar flow (shear stress and the minimum volume of the blood and vessel wall tissue is achieved when the vessel radii are adjusted to the cube root of the volumetric flow. The PMW is known to apply over several magnitudes of vessel calibers, and in many different organs, including the brain, in humans and in animals. Animal studies suggest that blood flow in arteries is approximately proportional to the cube of the vessel radius, and that arteries alter their caliber in response to sustained changes of blood flow according to PMW. Remodelling of the retinal arteriolar network to long-term changes in blood flow was observed in humans. Remodelling of whole arterial networks occurs in the form of increase or diminishing of vessel calibers. Shear stress induced endothelial mediation seems to be the regulating mechanism for the maintenance of this optimum blood flow/vessel diameter relation. Arterial trees are also expected to be nearly space filing. The vascular system is constructed in such a way that, while blood vessels occupy only a small percentage of the body volume leaving the bulk to tissue, they also crisscross organs so tightly that every point in the tissue lies on the boundary between an artery and a vein. This review describes how the energetic optimum principle for least energy cost for blood flow is also compatible with the spatial constraints of arterial networks according to concepts derived from fractal geometry.

  4. Assessment of the Temporopolar Artery as a Donor Artery for Intracranial-Intracranial Bypass to the Middle Cerebral Artery: Anatomic Feasibility Study.

    Science.gov (United States)

    Tayebi Meybodi, Ali; Lawton, Michael T; Griswold, Dylan; Mokhtari, Pooneh; Payman, Andre; Tabani, Halima; Yousef, Sonia; Kola, Olivia; Benet, Arnau

    2017-08-01

    Intracranial-intracranial bypass is a valuable cerebral revascularization option. Despite several advantages, one of the main shortcomings of the intracranial-intracranial bypass is the possibility of ischemic complications of the donor artery. However, when sacrificed, the temporopolar artery (TPA) is not associated with major neurologic deficits. We sought to define the role of TPA as a donor for revascularization of the middle cerebral artery (MCA). Pterional craniotomy was performed on 14 specimens. The TPA was released from arachnoid trabecula, and the small twigs to the temporal lobe were cut. The feasibility of side-to-side and end-to-side bypass to the farthest arterial targets on insular, opercular, and cortical MCA branches was assessed. The distance of the bypass point was measured in reference to limen insulae. A total of 15 TPAs were assessed (1 specimen had 2 TPAs). The average cisternal length of the TPA was 37.3 mm. For side-to-side bypass, the TPA was a poor candidate as an intracranial donor, except for the cortical orbitofrontal artery, which was reached in 87% of cases. However, the end-to-side bypass was successfully completed for most arteries (87%-100%) on the anterior frontal operculum and more than 50% of the cortical or opercular middle and posterior temporal arteries. There was no correlation between the TPA's cisternal length and maximum bypass reach. When of favorable diameter, the TPA is a competent donor for intracranial-intracranial bypass to MCA branches at the anterior insula, and anterior frontal and middle temporal opercula (arteries anterior to the precentral gyrus coronal plane). Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Anterior vaginal wall repair

    Science.gov (United States)

    ... may have you: Learn pelvic floor muscle exercises ( Kegel exercises ) Use estrogen cream in your vagina Try ... repair; Urinary incontinence - vaginal wall repair Patient Instructions Kegel exercises - self-care Self catheterization - female Suprapubic catheter ...

  6. Advanced walling systems

    CSIR Research Space (South Africa)

    De Villiers, A

    2010-01-01

    Full Text Available The question addressed by this chapter is: How should advanced walling systems be planned, designed, built, refurbished, and end their useful lives, to classify as smart, sustainable, green or eco-building environments?...

  7. A method for automatically constructing the initial contour of the common carotid artery

    Directory of Open Access Journals (Sweden)

    Yara Omran

    2013-10-01

    Full Text Available In this article we propose a novel method to automatically set the initial contour that is used by the Active contours algorithm.The proposed method exploits the accumulative intensity profiles to locate the points on the arterial wall. The intensity profiles of sections that intersect the artery show distinguishable characterstics that make it possible to recognize them from the profiles of sections that do not intersect the artery walls. The proposed method is applied on ultrasound images of the transverse section of the common carotid artery, but it can be extended to be used on the images of the longitudinal section. The intensity profiles are classified using Support vector machine algorithm, and the results of different kernels are compared. The extracted features used for the classification are basically statistical features of the intensity profiles. The echogenicity of the arterial lumen, and gives the profiles that intersect the artery a special shape that helps recognizing these profiles from other general profiles.The outlining of the arterial walls may seem a classic task in image processing. However, most of the methods used to outline the artery start from a manual, or semi-automatic, initial contour.The proposed method is highly appreciated in automating the entire process of automatic artery detection and segmentation.

  8. Towards General Temporal Aggregation

    DEFF Research Database (Denmark)

    Boehlen, Michael H.; Gamper, Johann; Jensen, Christian Søndergaard

    2008-01-01

    Most database applications manage time-referenced, or temporal, data. Temporal data management is difficult when using conventional database technology, and many contributions have been made for how to better model, store, and query temporal data. Temporal aggregation illustrates well the problem...

  9. Fast and Accurate Pressure-Drop Prediction in Straightened Atherosclerotic Coronary Arteries

    NARCIS (Netherlands)

    J.T.C. Schrauwen (Jelle); D. Koeze (Dion); J.J. Wentzel (Jolanda); F.N. van de Vosse (Frans); A.F.W. van der Steen (Ton); F.J.H. Gijsen (Frank)

    2014-01-01

    textabstractAtherosclerotic disease progression in coronary arteries is influenced by wall shear stress. To compute patient-specific wall shear stress, computational fluid dynamics (CFD) is required. In this study we propose a method for computing the pressure-drop in regions proximal and distal to

  10. Medial arterial calcification in diabetes and its relationship to neuropathy

    DEFF Research Database (Denmark)

    Jeffcoate, W J; Rasmussen, Lars Melholt; Hofbauer, L C

    2009-01-01

    is not strictly accurate because the morphological changes incorporate those of new bone formation, i.e. ossification. The processes are complex, but are closely related to those involved in bone homeostasis, and it is relevant that calcification of the arterial wall and osteopenia often co-exist. One particular...

  11. CO2 vascular anastomosis of atherosclerotic and calcified arteries

    Science.gov (United States)

    White, John V.; Leefmans, Eric; Stewart, Gwendolyn J.; Katz, Mira L.; Comerota, Anthony J.

    1990-06-01

    The technique for CO2 laser fusion vascular anastomosis in normal vessels has been well established. Normal arterial wall has a predictable thermal response to the incident laser energy, with rapid heating and cooling of collagen within the arterial wall. Since atherosclerosis involves subendothelial cellular proliferation, lipid and calcium deposition, it may modify the thermal responsiveness of the arterial wall. To this study, CO2 laser fusion anastomoses were attempted in rabbits with non-calcific atherosclerosis and humans with calcific atherosclerosis. All anastomoses were successfully completed without alteration in technique despite the presence of plaque at the site of laser fusion. Histology of rabbit vessels revealed the classic laser fusion cap within the adventitia and persistent atherosclerotic plaque at the flow surface. Duplex imaging of patients post-operatively demonstrated long term anastomotic patency in 2 of 3 fistulae. These results suggest that neither non-calcified or calcified atherosclerosis significantly alters the arterial wall thermal responsiveness to CO2 laser energy or inhibits creation of laser fusion anastomoses. Therefore, this technique may be applicable to the treatment of patients with atherosclerotic occlusive disease.

  12. Reappraisal of the structure of arterial Tunica adventitia and its ...

    African Journals Online (AJOL)

    Tunica adventitia was previously considered an inert fibrous layer only involved in nutritional and physical support of the arterial wall. Recent studies reveal that it is an important dynamic layer actively involved in the regulation of vascular structure, function, response to injury and disease processes especially ...

  13. Ultrasound Evaluation of Intima-Media Thickness of Carotid Arteries ...

    African Journals Online (AJOL)

    Background: Ultrasound measured Carotid Intima-Media Thickness (CIMT) is a simple and inexpensive tool for assessing the cumulative effects of hypertension on the carotid arterial walls. It is also an independent predictor of future myocardial infarctionand stroke risk. Objectives: This study compared ultrasound measured ...

  14. Hemodynamics Modeling and Simulation of Anterior Communicating Artery Aneurysms

    Directory of Open Access Journals (Sweden)

    Jianjun Li

    2014-07-01

    Full Text Available It is a general agreement that hemodynamics plays very important role in the initiation, growth, and rupture of cerebral aneurysms and hemodynamics in the anterior communicating artery aneurysms is considered the most complex in all cerebral aneurysms and it is difficult to find some reasonable relationship between the hemodynamics parameters and the rupture risk. In this paper, the 3D geometries of four anterior communicating artery aneurysms were generated from the CTA data and the computational models with bilateral feeding arteries for the four aneurysms were constructed. The blood flow was simulated by computational fluid dynamics software and the hemodynamics parameters such as velocity, wall shear stress, and oscillatory shear index were calculated. The following results were observed: one of the four models only needs the left feeding artery; the max normalized wall shear stress locates at the aneurysmal neck of the largest aneurysm; the max oscillatory shear index locates at the aneurysmal sac of the largest aneurysm. The conclusion was drawn that the anterior communicating artery aneurysm has higher rupture risk from the hemodynamics viewpoint if the max wall shear stress locates at the neck and the max oscillatory shear index locates at the dome.

  15. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output.

    Science.gov (United States)

    Smerup, Morten; Damkjær, Mads; Brøndum, Emil; Baandrup, Ulrik T; Kristiansen, Steen Buus; Nygaard, Hans; Funder, Jonas; Aalkjær, Christian; Sauer, Cathrine; Buchanan, Rasmus; Bertelsen, Mads Frost; Østergaard, Kristine; Grøndahl, Carsten; Candy, Geoffrey; Hasenkam, J Michael; Secher, Niels H; Bie, Peter; Wang, Tobias

    2016-02-01

    Giraffes--the tallest extant animals on Earth--are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. Arterial pressure may exceed 300 mmHg and has historically been attributed to an exceptionally large heart. Recently, this has been refuted by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It thus remains unexplained how the normal-sized giraffe heart generates such massive arterial pressures. We hypothesized that giraffe hearts have a small intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic pressures to calculate left ventricular wall stress. Cardiac output was also determined by inert gas rebreathing to provide an additional and independent estimate of stroke volume. Echocardiography and inert gas-rebreathing yielded similar cardiac outputs of 16.1±2.5 and 16.4±1.4 l min(-1), respectively. End-diastolic and end-systolic volumes were 521±61 ml and 228±42 ml, respectively, yielding an ejection fraction of 56±4% and a stroke volume of 0.59 ml kg(-1). Left ventricular circumferential wall stress was 7.83±1.76 kPa. We conclude that, relative to body mass, a small left ventricular cavity and a low stroke volume characterizes the giraffe heart. The adaptations result in typical mammalian left ventricular wall tensions, but produce a lowered cardiac output. © 2016. Published by The Company of Biologists Ltd.

  16. Notes on Cool: The Temporal Politics of Friendly Monsters and the E-waste Aesthetic

    Directory of Open Access Journals (Sweden)

    Sabine LeBel

    2015-06-01

    Full Text Available Notes on Cool: The Temporal Politics of Friendly Monsters and the E-waste Aesthetic by Sabine LeBel- nanocrit.com. Two compelling examples of e-waste, with the aim to educate and inform, albeit using different visual tactics than Burtynsky or Hugo, are WEEE Man and the film WALL-E. WEEE Man is a giant sculpture in the United Kingdom made entirely from e-waste. In WALL-E, e-waste is an important part of the devastated wastescapes of abandoned future earth. Both WEEE Man and WALL-E represent garbage and e-waste in terms of scale.

  17. Painful chewing and blindness: signs and symptoms of temporal arteritis.

    Science.gov (United States)

    Allen, D T; Voytovich, M C; Allen, J C

    2000-12-01

    This case report illustrates the need to consider temporal arteritis in the differential diagnosis of jaw or tooth pain. This disease affects the cranial arteries, more frequently in women and usually in those older than age 60 years, causing jaw pain, visual symptoms, headache, scalp pain and sometimes blindness. A 71-year-old man had jaw pain that increased with chewing and speaking, scalp tenderness and dimming vision. A temporal artery biopsy confirmed the diagnosis of temporal arteritis. Treatment with decreasing amounts of oral steroids over 23 months was successful in relieving his signs and symptoms and in saving his vision. Patients with this disease may seek care from their dentist first. Jaw or tooth pain is the most reliable clinical symptom in the diagnosis of temporal arteritis. Diagnosis and timely referral for treatment with oral steroids can prevent blindness.

  18. KETERASINGAN DALAM FILM WALL-E

    Directory of Open Access Journals (Sweden)

    Rahmadya Putra Nugraha

    2017-05-01

    Full Text Available Modern society nowadays technological advances at first create efficiency in human life. Further development of the technology thus drown human in a routine and automation of work created. The State is to be one of the causes of man separated from fellow or the outside world and eventually experiencing alienation. The movie as a mass media function to obtain the movie and entertainment can be informative or educative function is contained, even persuasive. The purpose of this research was conducted to find out the alienation in the movie Wall E. The concepts used to analyze the movie Wall E this is communication, movie, and alienation. The concept of alienation of human alienation from covering its own products of human alienation from its activities, the human alienation from nature of his humanity and human alienation from each other. Paradigm used is a critical paradigm with type a descriptive research with qualitative approach. The method used is the analysis of semiotics Roland Barthes to interpretation the scope of social alienation and fellow humans in the movie.This writing research results found that alienation of humans with other humans influenced the development of the technology and how the human it self represented of technology, not from our fellow human beings. Masyarakat modern saat ini kemajuan teknologi pada awalnya membuat efisiensi dalam kehidupan manusia. Perkembangan selanjutnya teknologi justru menenggelamkan manusia dalam suatu rutinitas dan otomatisasi kerja yang diciptakan. Keadaan itulah yang menjadi salah satu penyebab manusia terpisah dari sesama atau dunia luar dan akhirnya mengalami keterasingan. Film sebagai media massa berfungsi untuk memperoleh hiburan dan dalam film dapat terkandung fungsi informatif maupun edukatif, bahkan persuasif. Tujuan Penelitian ini dilakukan untuk mengetahui Keterasingan dalam film Wall E. Konsep-konsep yang digunakan untuk menganalisis film Wall E ini adalah komunikasi, film, dan

  19. Pressure Myography to Study the Function and Structure of isolated small arteries

    DEFF Research Database (Denmark)

    Schjørring, Olav; Carlsson, Rune; Simonsen, Ulf

    2015-01-01

    Small arteries play an important role in regulation of peripheral resistance and organ perfusion. Here we describe a series of the methods allowing measurements in pressurized segments of small arteries from the systemic and coronary circulation of mice as well as other species. The pressure...... myography techniques described include measurements of wall structure, wall stress, strain, and of myogenic tone. The pressurized perfused small arteries also allow evaluation of responses to increases in pressure, flow, and drugs, where the main readout is changes in vascular diameter....

  20. testicular artery arising from an aberrant right renal artery

    African Journals Online (AJOL)

    User

    2017-08-17

    Aug 17, 2017 ... Correspondence to Dr. Emmanuel Henry Suluba, Department of Anatomy, School of Medicine,. Muhimbili University of Health and ... vein, left colic artery and the descending colon. Both right and left testicular arteries as ... anatomy of the vessels such as testicular arteries, ovarian arteries, renal arteries and.

  1. Acute radiographic workup of blunt temporal bone trauma: maxillofacial versus temporal bone CT.

    Science.gov (United States)

    Dempewolf, Ryan; Gubbels, Sam; Hansen, Marlan R

    2009-03-01

    To evaluate the radiographic workup of blunt temporal bone trauma and determine the utility of maxillofacial computed tomography (CT) versus temporal bone CT in identifying carotid canal fractures. Retrospective review. The charts of 227 patients evaluated at a level I trauma center receiving a temporal bone CT for blunt head trauma within 48 hours of admission were reviewed. Acute evaluation findings and complications were noted. Sensitivity, specificity, positive predictive value, and negative predictive (NPV) value were calculated for maxillofacial CT's ability to identify carotid canal fractures compared to temporal bone CT. One hundred forty fractures were found. Physical exam findings of blood in the external auditory canal as the sole finding, and blood in the external auditory canal with associated hemotympanum were significantly associated with absence and presence of fracture respectively. The sensitivity and specificity of maxillofacial CT for identifying carotid canal fractures, when compared to temporal bone CT, were 90.3% and 94.4% respectively (NPV > 95%). Only 6% of all patients either did have or should have had their management changed based on the temporal bone CT findings. All of these changes were regarding further workup for blunt carotid artery injury. A combination of helical computed tomography and physical exam findings can allow for judicious use of temporal bone CTs when no maxillofacial CT is indicated. Temporal bone CTs rarely change acute management. But when they do, it is in regard to the need for further workup of possible vascular injury. Lastly, maxillofacial CTs are adequate for identifying carotid canal fractures.

  2. Duplicated middle cerebral artery

    Science.gov (United States)

    Perez, Jesus; Machado, Calixto; Scherle, Claudio; Hierro, Daniel

    2009-01-01

    Duplicated middle cerebral artery (DMCA) is an anomalous vessel arising from the internal carotid artery. The incidence DMCA is relatively law, and an association between this anomaly and cerebral aneurysms has been documented. There is a controversy whether DMCA may have perforating arteries. This is an important fact to consider in aneurysm surgery. We report the case of a 34-year-old black woman who suffered a subarachnoid hemorrhage and the angiography a left DMCA, and an aneurysm in an inferior branch of the main MCA. The DMCA and the MCA had perforating arteries. The aneurysm was clipped without complications. The observation of perforating arteries in our patient confirms that the DMCA may have perforating arteries. This is very important to be considered in cerebral aneurysms surgery. Moreover, the DMCA may potentially serve as a collateral blood supply to the MCA territory in cases of MCA occlusion. PMID:22140405

  3. Study of the course of inferior epigastric artery with reference to laparoscopic portal

    OpenAIRE

    Manvikar Purushottam Rao; Vatsala Swamy; Vasanti Arole; Paramatma Mishra

    2013-01-01

    Introduction: Laparoscopy has been in vogue for more than 2 decades. Making portals in the anterior abdominal wall for introducing laparoscopic instruments is done with trocar and cannula which is a blind procedure. Stab incision and trocar insertion, though safe, at times can lead to injury of blood vessels of anterior abdominal wall more so the inferior epigastric artery (IEA). Trauma to abdominal wall vessels is 0.2%-2% of laparoscopic procedures and said to be 3 per 1000 cases. Injury to ...

  4. Relation between zero-stress state and branching order of porcine left coronary arterial tree.

    Science.gov (United States)

    Frøbert, O; Gregersen, H; Bjerre, J; Bagger, J P; Kassab, G S

    1998-12-01

    The left common coronary arterial trees of eight pig hearts were dissected. The zero-stress state (the state of the organ when the external loads are removed) of the coronary arteries was determined by first cutting the arteries into short, ring-shaped segments perpendicular to the longitudinal axis of the blood vessel and then making a radial cut. This procedure caused the ring to open into a sector whose opening angle (theta), internal and external lengths (circumferences), and wall thickness were measured. Morphometric and theta data were organized in the framework of a diameter-defined Strahler system. We investigated 4 rings from the left common coronary artery (LCCA), 185 from the left anterior descending artery (LAD) and its branches, and 159 from the left circumflex artery (LCX) and its branches. The inner circumferences of the rings ranged over six orders for the LAD arterial tree and five orders for the LCX arterial tree, corresponding to a diameter range of about one order of magnitude for both arteries. theta demonstrates viscoelastic behavior and was measured 30 min after cutting. Our results show that the inner and outer circumference and the wall thickness increase as geometric sequences with the order number. theta is found to decrease linearly toward the smaller orders with a slope of 7.3 degrees/order in the range of the six largest orders. Strain calculations showed that the inner part of the arterial wall is in compression, whereas the outer part of the wall is in tension in the no-load (zero transmural pressure) state. This study provides basic data on the zero-stress state that are necessary for understanding the mechanics of the coronary artery.

  5. Nitroglycerin-induced heterogeneous subendocardial myocardial blood flow observed by cardioscopy in patients with coronary artery disease.

    Science.gov (United States)

    Uchida, Yasuto; Uchida, Yasumi; Maezawa, Yuko; Maezawa, Yoshiro; Sakurai, Takeshi; Kanai, Masahito; Shirai, Seiichiro; Tabata, Tsuyoshi

    2011-01-01

    It is controversial as to whether or not nitroglycerin (NTG) increases subendocardial myocardial blood flow (SMBF), and if it does, whether arterial or venous blood flow is increased in patients with coronary artery disease. This study was performed to examine NTG-induced changes in SMBF.Changes in SMBF induced by NTG (200 µg, i.v.) were examined by cardioscopy in 58 left ventricular wall segments of 58 patients with coronary artery disease. NTG-induced red and purple endocardial colors were defined as increased arterial and venous SMBF, respectively. Endocardial color before NTG administration was classified into brown, light brown, pale and white. Endomyocardial biopsy of the observed portion and (201)Tl scintigraphy were performed in 40 of these patients immediately after cardioscopy and several days after cardioscopy, respectively.Upon administration of NTG, SMBF increased in 48 of 58 wall segments; arterial SMBF in 34 and venous SMBF in 12 wall segments; arterial SMBF in all 24 brown to light brown segments; venous SMBF, arterial SMBF and no change in 12, 10 and 5 of pale segments, respectively; and no change in all 10 white wall segments. (201)Tl-scintigraphy and endomyocardial biopsy revealed that brown, light brown, pale and white endocardial color represented no ischemia, mild ischemia, severe ischemia and fibrosis, respectively.NTG caused an increase in either arterial or venous SMBF depending on control endocardial color, wall motion and severity of coronary stenosis.

  6. Popliteal artery entrapment syndrome.

    LENUS (Irish Health Repository)

    O'Leary, D P

    2010-01-01

    Popliteal artery entrapment syndrome is a rare abnormality of the anatomical relationship between the popliteal artery and adjacent muscles or fibrous bands in the popliteal fossa. The following is a case report of a 19 year old female, in whom popliteal artery entrapment syndrome was diagnosed, and successfully treated surgically. A review of literature is also presented and provides details on how PAES is classified, diagnosed both clinically and radiologically, and treated surgically.

  7. Celiac Artery Compression Syndrome

    Directory of Open Access Journals (Sweden)

    Mohammed Muqeetadnan

    2013-01-01

    Full Text Available Celiac artery compression syndrome is a rare disorder characterized by episodic abdominal pain and weight loss. It is the result of external compression of celiac artery by the median arcuate ligament. We present a case of celiac artery compression syndrome in a 57-year-old male with severe postprandial abdominal pain and 30-pound weight loss. The patient eventually responded well to surgical division of the median arcuate ligament by laparoscopy.

  8. Geometric analysis and blood flow simulation of basilar artery.

    Science.gov (United States)

    Lee, Sang Hyuk; Hur, Nahmkeon; Jeong, Seul-Ki

    2012-01-01

    The aim of this study was to find a region of low wall shear stress (WSS) in a basilar artery using 3-dimensional (3D) geometric analysis and blood flow simulation. A 61-year-old patient who underwent follow-up time-of-flight magnetic resonance angiography (TOF-MRA) of the brain was recruited as the subject of the present study. In the basilar artery, the angle of the directional vector was calculated for the region of low WSS. The subject's 3D arterial geometry and blood flow velocity from a transcranial Doppler examination were used for a blood flow simulation study. The regions of low WSS identified by both geometric analysis and blood flow simulation were compared, and these methods were repeated for the basilar arteries of various geometries from other patients. Two distinct arterial angulations along the basilar artery were identified: lateral and anterior angulations on the anteroposterior and lateral TOF-MR views, respectively. A low WSS region was observed in the distal portion along the inner curvatures of both angulations in the basilar artery. The directional vectors of the region of low WSS calculated by geometric analysis and blood flow simulation were very similar (correlation coefficient= 0.996, p flow simulation of the basilar artery identified lateral and anterior angulations which determined the low WSS region in the distal portion along the inner curvatures of the angulations.

  9. Cigarette smoking in military pilots and intima-media thickness of the carotid arteries

    Directory of Open Access Journals (Sweden)

    Jovelić Stojan

    2005-01-01

    Full Text Available Background. It is well known that smoking is associated with an increase in arterial wall thickness. However, most studies of this problem have been undertaken in age and sex heterogeneous groups, as well as in patients with already present other conventional risk factors. The aim of this study was to assess the effect of cigarette smoking on arterial wall thickness of the common carotid artery in asymptomatic pilots. Methods. The imaging of intima−media thickness of the posterior wall of the distal 1 cm of both common carotid arteries was performed using a B mode ultrasound device, in 39 pilots (37.05 ± 6.66 years, for whom smoking was the single cardiovascular risk factor. Comparisons were made with 49 non-smokers (35.12 ± 7.39 years. Results. The posterior walls of both common carotid arteries were thicker in smokers (left, p < 0.05; right, p > 0,05. Intima-media thickness was significantly lower on the right side than on the left side in both smokers and nonsmokers (p < 0.01. Conclusion. Cigarette smoking as the single cardiovascular risk factor was associated with the wall thickness of the carotid arteries in our study. This finding indicated that early atherosclerosis was already present in pilots - smokers entering middle age.

  10. Internal carotid artery rupture caused by carotid shunt insertion.

    Science.gov (United States)

    Illuminati, Giulio; Caliò, Francesco G; Pizzardi, Giulia; Vietri, Francesco

    2015-01-01

    Shunting is a well-accepted method of maintaining cerebral perfusion during carotid endarterectomy (CEA). Nonetheless, shunt insertion may lead to complications including arterial dissection, embolization, and thrombosis. We present a complication of shunt insertion consisting of arterial wall rupture, not reported previously. A 78-year-old woman underwent CEA combined with coronary artery bypass grafting (CABG). At the time of shunt insertion an arterial rupture at the distal tip of the shunt was detected and was repaired via a small saphenous vein patch. Eversion CEA and subsequent CABG completed the procedure whose postoperative course was uneventful. Shunting during combined CEA-CABG may be advisable to assure cerebral protection from possible hypoperfusion due to potential hemodynamic instability of patients with severe coronary artery disease. Awareness and prompt management of possible shunt-related complications, including the newly reported one, may contribute to limiting their harmful effect. Arterial wall rupture is a possible, previously not reported, shunt-related complication to be aware of when performing CEA. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Theoretical study on the constricted flow phenomena in arteries

    Science.gov (United States)

    Sen, S.; Chakravarty, S.

    2012-12-01

    The present study is dealt with the constricted flow characteristics of blood in arteries by making use of an appropriate mathematical model. The constricted artery experiences the generated wall shear stress due to flow disturbances in the presence of constriction. The disturbed flow in the stenosed arterial segment causes malfunction of the cardiovascular system leading to serious health problems in the form of heart attack and stroke. The flowing blood contained in the stenosed artery is considered to be non-Newtonian while the flow is treated to be two-dimensional. The present pursuit also accounts for the motion of the arterial wall and its effect on local fluid mechanics. The flow analysis applies the time-dependent, two-dimensional incompressible nonlinear Navier-Stokes equations for non-Newtonian fluid representing blood. An extensive quantitative analysis presented at the end of the paper based on large scale numerical computations of the quantities of major physiological significance enables one to estimate the constricted flow characteristics in the arterial system under consideration which deviates significantly from that of normal physiological flow conditions.

  12. The absent inferior epigastric artery: a unique anomaly and implications for deep inferior epigastric artery perforator flaps.

    Science.gov (United States)

    Rozen, Warren M; Houseman, Nicholas D; Ashton, Mark W

    2009-06-01

    The abdominal wall is particularly advantageous as a donor site due to the reliability of its vascular supply. Although the cutaneous perforators of the deep inferior epigastric artery (DIEA) and the superficial inferior epigastric artery (SIEA) may show significant individual variability, the DIEA itself has been shown to be ever-present as a vascular pedicle and to be highly dependable. The increasing use of preoperative computed tomographic angiography (CTA) has led to increasing reports of anatomic variability. With the use of preoperative CTA, we describe a unique case of a completely absent DIEA in patient who had not previously undergone any open abdominal surgery. The absence of the DIEA had led to vascular changes throughout the abdominal wall, including dilatation of both SIEAs and the ipsilateral deep superior epigastric artery. Preoperative CTA in this setting helped us identify this anomaly and aided surgical planning. The incidence of this anomaly was subsequently reviewed in 150 consecutive CTA scans performed at our institution.

  13. Renal Branch Artery Stenosis

    DEFF Research Database (Denmark)

    Andersson, Zarah; Thisted, Ebbe; Andersen, Ulrik Bjørn

    2017-01-01

    Renovascular hypertension is a common cause of pediatric hypertension. In the fraction of cases that are unrelated to syndromes such as neurofibromatosis, patients with a solitary stenosis on a branch of the renal artery are common and can be diagnostically challenging. Imaging techniques...... that perform well in the diagnosis of main renal artery stenosis may fall short when it comes to branch artery stenosis. We report 2 cases that illustrate these difficulties and show that a branch artery stenosis may be overlooked even by the gold standard method, renal angiography....

  14. Atherosclerotic femoral artery aneurysms

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Schroeder, T V

    1996-01-01

    Based on a clinical suspicion of an increase in the proportion of deep femoral aneurysms, we reviewed the case records of patients who underwent reconstructive procedures for femoral aneurysms to investigate if this could be confirmed and explained by selection of patient or modality of diagnosis...... femoral artery and 3 the deep femoral artery. The proportion of deep femoral aneurysm was therefore 3/17 = 18%. Previous series report that aneurysms of the profunda femoris artery occurs in only 1% to 2.6% of all femoral artery aneurysms. No explanation was found for this significant increase (p

  15. Simulation of a pulsatile non-Newtonian flow past a stenosed 2D artery with atherosclerosis.

    Science.gov (United States)

    Tian, Fang-Bao; Zhu, Luoding; Fok, Pak-Wing; Lu, Xi-Yun

    2013-09-01

    Atherosclerotic plaque can cause severe stenosis in the artery lumen. Blood flow through a substantially narrowed artery may have different flow characteristics and produce different forces acting on the plaque surface and artery wall. The disturbed flow and force fields in the lumen may have serious implications on vascular endothelial cells, smooth muscle cells, and circulating blood cells. In this work a simplified model is used to simulate a pulsatile non-Newtonian blood flow past a stenosed artery caused by atherosclerotic plaques of different severity. The focus is on a systematic parameter study of the effects of plaque size/geometry, flow Reynolds number, shear-rate dependent viscosity and flow pulsatility on the fluid wall shear stress and its gradient, fluid wall normal stress, and flow shear rate. The computational results obtained from this idealized model may shed light on the flow and force characteristics of more realistic blood flow through an atherosclerotic vessel. Copyright © 2013. Published by Elsevier Ltd.

  16. Near Wall Turbulence: an experimental view

    Science.gov (United States)

    Stanislas, Michel

    2016-11-01

    The aim of this presentation is to summarize the understanding of the near wall turbulence phenomena obtained at Laboratoire de Mécanique de Lille using both hot wire anemometry and PIV. A wind tunnel was built in 1993 specifically designed for these two measurement techniques and aimed at large Reynolds numbers. Several experiments were performed since then in the frame of different PhDs and European projects, all aimed at evidencing turbulence organization in this region. These have fully benefited of the extraordinary development of PIV in that time frame, which has allowed entering visually and quantitatively inside the complex spatial and temporal structure of near wall turbulence. The presentation will try to emphasize the benefit of this approach in terms of understanding and modelling, illustrated by some representative results obtained. M. Stanislas particularly acknowledges the financial support of Region Nord Pas de Calais, unmissing during 25 years.

  17. Electroweak bubble wall speed limit

    Science.gov (United States)

    Bödeker, Dietrich; Moore, Guy D.

    2017-05-01

    In extensions of the Standard Model with extra scalars, the electroweak phase transition can be very strong, and the bubble walls can be highly relativistic. We revisit our previous argument that electroweak bubble walls can "run away," that is, achieve extreme ultrarelativistic velocities γ ~ 1014. We show that, when particles cross the bubble wall, they can emit transition radiation. Wall-frame soft processes, though suppressed by a power of the coupling α, have a significance enhanced by the γ-factor of the wall, limiting wall velocities to γ ~ 1/α. Though the bubble walls can move at almost the speed of light, they carry an infinitesimal share of the plasma's energy.

  18. Reconstruction of lateral attic wall in acquired cholesteatoma

    Directory of Open Access Journals (Sweden)

    Erdoglija Milan

    2017-01-01

    Full Text Available Background/Aim. Attic cholesteatoma is an epithelial cystic pseudotumor which arises in the top compartment of the middle ear. Surgery is the only therapeutic treatment for attic cholesteatoma. The aim of this study was to analyze the surgical and audiological results in tympanoplasties that use a logical application of several techniques for the management of attic cholesteatoma. Our hypothesis was that the tympanoplasty technique with cartilage/bone reconstruction of the achieve better outcome than the tympanoplasty technique with only temporal fascia reconstruction of the lateral attic wall. Methods. This retrospective clinical study included 80 patients, aged 16–65 years, with attic cholesteatoma undergoing canal “wall up” tympanoplasty with lateral attic wall reconstruction, under general anesthesia in the Eear, Nose and Throat Clinic, Military Medical Academy in Belgrade between 2006 and 2010. The patients were divided into two groups according to the type of lateral attic wall reconstruction: the group I of 60 patients with cartilage/bone plus temporalis fascia lateral attic wall reconstruction and the group II of 20 patients with only temporal fascia lateral attic wall reconstruction. Postoperative follow-up examinations were done at least 5 years after the surgery. The χ2 test was used to compare postoperative sequelae for two groups of operated patients with lateral attic wall reconstruction. The independent and paired samples t-test of air conduction and air-bone gap were used to compare the results of preoperative and postoperative hearing tests. Results. The differences between hearing measurements of the two groups according to preoperative and postoperative auditory thresholds of the air conduction and the air-bone gap were considered no statistically significant. The difference between the two groups recarding to recurrent attic retraction pocket appearance and recurrence of cholesteatoma was considered statistically

  19. 3D cardiac wall thickening assessment for acute myocardial infarction

    Science.gov (United States)

    Khalid, A.; Chan, B. T.; Lim, E.; Liew, Y. M.

    2017-06-01

    Acute myocardial infarction (AMI) is the most severe form of coronary artery disease leading to localized myocardial injury and therefore irregularities in the cardiac wall contractility. Studies have found very limited differences in global indices (such as ejection fraction, myocardial mass and volume) between healthy subjects and AMI patients, and therefore suggested regional assessment. Regional index, specifically cardiac wall thickness (WT) and thickening is closely related to cardiac function and could reveal regional abnormality due to AMI. In this study, we developed a 3D wall thickening assessment method to identify regional wall contractility dysfunction due to localized myocardial injury from infarction. Wall thickness and thickening were assessed from 3D personalized cardiac models reconstructed from cine MRI images by fitting inscribed sphere between endocardial and epicardial wall. The thickening analysis was performed in 5 patients and 3 healthy subjects and the results were compared against the gold standard 2D late-gadolinium-enhanced (LGE) images for infarct localization. The notable finding of this study is the highly accurate estimation and visual representation of the infarct size and location in 3D. This study provides clinicians with an intuitive way to visually and qualitatively assess regional cardiac wall dysfunction due to infarction in AMI patients.

  20. Upper lip reconstruction using a pedicel superficial temporal artery flap

    Directory of Open Access Journals (Sweden)

    Mohammad M. Al-Qattan

    2018-01-01

    Conclusion: We demonstrate that the pedicle flap is much simpler than the free flap and is adequate for reconstruction of partial upper lip defects. We also demonstrate a good cosmetic and functional outcome; and highlight several technical points to ensure a satisfactory outcome.

  1. [Neck pain and headache as the only manifestation of cervical artery dissection].

    Science.gov (United States)

    Kalashnikova, L A; Dobrinina, L A; Dreval, M V; Doronina, E V; Nazarova, M A

    2015-01-01

    To analyze clinical and neuroimaging data in patients with neck pain and headache as the only manifestation of the internal carotid artery (ICA) dissection (ICAD) and vertebral artery (VA) dissection (VAD). One hundred and sixty-one patients (mean age - 37.4±4,99 years, 84 women, 52%) with cervical artery dissection (CAD) verified by magnetic resonance imaging (MRI) were enrolled. Neck pain and headache were the only CAD manifestation in 33 patients (mean age 37,3±7,4 yars, 28 women, 85%). The localization of the dissections in these patients was the following: one VA (15 patients), two VA (9), one ICA (7), two ICA (1), one ICA + two VA (1). The whole number of dissected arteries was 45: extracranial localization - 38, extra-intracranial - 6, intracranial - 1. Dissection led to stenosis of the arterial lumen in 41 arteries, to occlusion - in 2 and to dual lumen in 2 arteries. Small aneurism was found in 4 arteries. Combination of headache and the neck pain was observed in 26 out of 33 patients (79%), the only headache in 4 patients, the only neck pain in 3 patients. Along with this, 9 out of 24 VAD patients had the shoulder and/or arm pain. Headache in VAD patients was located more often in the occipital region (18 out of 24) that had never been observed in ICAD patients (p=0.0009). Fronto-temporal pain was observed more often in ICAD patients (5 out of 8 patients) than in VAD (2 out of 24 patients) (p=0.003). Neck pain in all VAD patients in comparison with 3 out ofI8 [CAD patients had posterior localization (p=0,007). Anterolateral neck pain was observed in 4 out ofI8 ICAD patients and in no patients with VAD (p=0.0009). The pain appearance was abrupt in all ICAD patients and most of the VAD patients. In 8 VAD patients the pain has been increasing during several hours. The pain intensity was severe in 19 patients, moderate in 12 and mild in 2. The characteristics of the pain were as following: constrictive/dull (26 patients), throbbing (1 patient) or combined

  2. Do diabetes mellitus and systemic hypertension predispose to left ventricular free wall rupture in acute myocardial infarction?

    DEFF Research Database (Denmark)

    Melchior, T; Hildebrant, P; Køber, L

    1997-01-01

    Diabetes and systemic hypertension had no influence on left ventricular free wall rupture complicating acute myocardial infarction. Age <65 years and a history of coronary artery disease offers some protection from protection.......Diabetes and systemic hypertension had no influence on left ventricular free wall rupture complicating acute myocardial infarction. Age

  3. Constitutive modeling of human femoropopliteal artery biaxial stiffening due to aging and diabetes.

    Science.gov (United States)

    Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

    2017-12-01

    Atherosclerotic obstructive disease of the femoropopliteal artery (Peripheral Arterial Disease, PAD) is notorious for high treatment failure rates. Older age and diabetes mellitus (DM) are among the major risk factors for PAD, and both are associated with increased arterial stiffness. Our goal was to develop a constitutive model describing multiaxial arterial stiffening, and use it to portray aging of normal and diabetic human femoropopliteal arteries (FPA). Fresh human FPAs (n=744) were obtained from 13-82-year-old donors. Arteries were tested using planar biaxial extension, and their behavior was modeled with a constitutive relation that included stiffening functions of age. FPA diameter, wall thickness, circumferential, and longitudinal opening angles increased with age, while longitudinal pre-stretch decreased. Diameter and circumferential opening angle did not change with age in subjects with DM. Younger FPAs were more compliant longitudinally but became more isotropic with age. Arteries with DM stiffened significantly faster in the circumferential direction than arteries without DM. Constitutive model accurately portrayed orthotropic stiffening with age of both normal and diabetic arteries. Constitutive description of FPA aging contributes to understanding of arterial pathophysiology and can help improve fidelity of computational models investigating device-artery interaction in PAD repair by providing more personalized arterial properties. We have analyzed n=744 human femoropopliteal artery (FPA) specimens using biaxial tensile testing to derive constitutive description of FPA aging in diabetic and non-diabetic subjects. The proposed model allows determination of FPA mechanical properties for subjects of any given age in the range of 13-82years. These results contribute to understanding of FPA pathophysiology and can help improve fidelity of computational models investigating device-artery interaction in peripheral arterial disease repair by providing more

  4. Semantics of Temporal Models with Multiple Temporal Dimensions

    DEFF Research Database (Denmark)

    Kraft, Peter; Sørensen, Jens Otto

    Semantics of temporal models with multi temporal dimensions are examined progressing from non-temporal models unto uni-temporal, and further unto bi- and tri-temporal models. An example of a uni-temporal model is the valid time model, an example of a bi-temporal model is the valid time/transactio...

  5. Recurrent post-partum coronary artery dissection

    Directory of Open Access Journals (Sweden)

    Resnic Frederic S

    2010-10-01

    Full Text Available Abstract Coronary artery dissection is a rare but well-described cause for myocardial infarction during the post-partum period. Dissection of multiple coronary arteries is even less frequent. Here we present a case of recurrent post-partum coronary artery dissections. This unusual presentation poses unique problems for management. A 35 year-old female, gravida 3 para 2, presented with myocardial infarction 9 weeks and 3 days post-partum. Cardiac catheterization demonstrated left anterior descending (LAD dissection but an otherwise normal coronary anatomy. The lesion was treated with four everolimus eluting stents. Initially the patient made an unremarkable recovery until ventricular fibrillation arrest occurred on the following day. Unsynchronized cardioversion restored a normal sinus rhythm and repeat catheterization revealed new right coronary artery (RCA dissection. A wire was passed distally, but it was unclear whether this was through the true or false lumen and no stents could be placed. However, improvement of distal RCA perfusion was noted on angiogram. Despite failure of interventional therapy the patient was therefore treated conservatively. Early operation after myocardial infarction has a significantly elevated risk of mortality and the initial dissection had occurred within 24 hours. This strategy proved successful as follow-up transthoracic echocardiography after four months demonstrated a preserved left ventricular ejection fraction of 55-60% without regional wall motion abnormalities. The patient remained asymptomatic from a cardiac point of view.

  6. Stenting of Extracranial Carotid Artery Stenosis

    Science.gov (United States)

    Koshimae, N.; Morimoto, T.; Nagata, K.

    2003-01-01

    Summary The purpose of this study is to evaluate our cases of cervical internal carotid artery stenosis for safty stenting. We investigate the preoperative internal carotid artery stenosis using by integrated backscatter (IBS) method of ultra sonography, comparing with the thirty five surgical specimens as to their nature, histological structure, thickness of fibrous cap. We choose the protection method according to plaque structure, and placed Easy-Wall stent or Smart stent after prePTA. We added post PTA according to the extent of expansion and IVUS findings. Calibrated IBS = IBS value (ROI) /intinal IBS value of ‘bleeding’, ‘lipiď, ‘thrombus’, fiber, ‘hyalinization’ were -27.5, -22.5, -15.2, -11.1, +2.1. That of the thin fibrous cap were -10.9*, that of thic fibrous cap were -2.4 (*p safty stenting. PMID:20591243

  7. Left ventricular wall motion in patients with Chagas's disease.

    Science.gov (United States)

    Hammermeister, K E; Caeiro, T; Crespo, E; Palmero, H; Gibson, D G

    1984-01-01

    The effect of early chronic Chagas's disease on the timing and extent of regional left ventricular wall motion was studied with a frame by frame analysis of left ventriculograms in nine patients and compared with those in 19 normal subjects. In all the patients there was hypokinesis or akinesis in the anteroapical region together with delay in the onset of inward movement. Hypokinesis of the proximal inferior segment was also present, but the time of onset of inward motion here was normal. These differences can be explained on the basis of regional asynchrony within the normal left ventricle, where anteroapical wall motion is delayed with respect to that elsewhere. Thus contraction of the diseased anteroapical segment starts against an appreciable pressure and so may be isometric, whereas the affected proximal inferior segment starts contracting earlier against a lower pressure and so is able to shorten. No abnormalities of wall motion were seen during isovolumic relaxation despite segmental involvement, which is a distinctly different finding from that in patients with coronary artery disease. This may be due partly to the absence of incoordinate relaxation in Chagas's disease and partly to myocardial involvement by Chagas's disease in the mid-anterior segment. This is the site of rapid early diastolic wall thinning, which has been put forward as a major mechanism of normal rapid ventricular filling and whose premature activity causes disturbances in regional wall motion before mitral valve opening when relaxation is incoordinate. Thus quantitative analysis of both the timing and amplitude of wall motion indicates fundamental differences between Chagas's disease and coronary artery disease, when a less complex analysis would have shown a similar pattern of segmental dysfunction in both. Since the effect of the same pathological process on wall motion varies with the site of ventricular involvement, the importance of the disturbances seen in Chagas's disease

  8. Heritability of cilioretinal arteries

    DEFF Research Database (Denmark)

    Taarnhøj, Nina Charlotte; Munch, Inger C; Kyvik, Kirsten O

    2005-01-01

    of healthy monozygotic and dizygotic twins were examined using digital fundus photography and visual assessment of grayscale fundus photographs and color transparencies to detect the presence of cilioretinal arteries. RESULTS: Cilioretinal arteries were present in 45.1% of participants and 28.8% of eyes...

  9. Peripheral artery disease - legs

    Science.gov (United States)

    ... the legs, feet, and toes Painful, non-bleeding sores on the feet or toes (most often black) that are slow ... block small arteries Coronary artery disease Impotence Open sores ... (gangrene) The affected leg or foot may need to be amputated

  10. Carotid Artery Screening

    Science.gov (United States)

    ... that look for inherited genetic markers linked to disease, and imaging tests that produce pictures of the inside of the body. These ... a risk factor. Risk factors for carotid artery disease include: age high blood pressure diabetes tobacco smoking high cholesterol coronary artery disease (CAD) obesity ...

  11. Current insights on the pathogenesis of pulmonary arterial hypertension.

    Science.gov (United States)

    Perros, Frédéric; Dorfmüller, Peter; Humbert, Marc

    2005-08-01

    Regardless of the initial trigger, the elevated pulmonary arterial pressure and vascular resistance in patients with pulmonary arterial hypertension are primarily caused by remodeling and thrombosis of small- and medium-sized pulmonary arteries and arterioles, as well as sustained vasoconstriction. The process of pulmonary vascular remodeling involves all layers of the vessel wall and is complicated by cellular heterogeneity within each compartment. Indeed, each cell type (endothelial cells, smooth muscle cells, and fibroblasts), as well as inflammatory cells and platelets, may play significant roles in this condition. Recent studies have emphasized the relevance of several mediators in this condition, including prostaglandin-I (2) (prostacyclin), nitric oxide, endothelin-1, angiopoietin-1, 5-hydroxytryptamine (serotonin), cytokines, chemokines, and members of the transforming growth factor beta (TGF-beta) superfamily. Targeting some of these dysfunctional pathways (prostacyclin, nitric oxide, and endothelin-1) has been beneficial in subjects displaying pulmonary arterial hypertension.

  12. An Integrative Model of the Cardiovascular System Coupling Heart Cellular Mechanics with Arterial Network Hemodynamics

    Science.gov (United States)

    Kim, Young-Tae; Lee, Jeong Sang; Youn, Chan-Hyun; Choi, Jae-Sung

    2013-01-01

    The current study proposes a model of the cardiovascular system that couples heart cell mechanics with arterial hemodynamics to examine the physiological role of arterial blood pressure (BP) in left ventricular hypertrophy (LVH). We developed a comprehensive multiphysics and multiscale cardiovascular model of the cardiovascular system that simulates physiological events, from membrane excitation and the contraction of a cardiac cell to heart mechanics and arterial blood hemodynamics. Using this model, we delineated the relationship between arterial BP or pulse wave velocity and LVH. Computed results were compared with existing clinical and experimental observations. To investigate the relationship between arterial hemodynamics and LVH, we performed a parametric study based on arterial wall stiffness, which was obtained in the model. Peak cellular stress of the left ventricle and systolic blood pressure (SBP) in the brachial and central arteries also increased; however, further increases were limited for higher arterial stiffness values. Interestingly, when we doubled the value of arterial stiffness from the baseline value, the percentage increase of SBP in the central artery was about 6.7% whereas that of the brachial artery was about 3.4%. It is suggested that SBP in the central artery is more critical for predicting LVH as compared with other blood pressure measurements. PMID:23960442

  13. An integrative model of the cardiovascular system coupling heart cellular mechanics with arterial network hemodynamics.

    Science.gov (United States)

    Kim, Young-Tae; Lee, Jeong Sang; Youn, Chan-Hyun; Choi, Jae-Sung; Shim, Eun Bo

    2013-08-01

    The current study proposes a model of the cardiovascular system that couples heart cell mechanics with arterial hemodynamics to examine the physiological role of arterial blood pressure (BP) in left ventricular hypertrophy (LVH). We developed a comprehensive multiphysics and multiscale cardiovascular model of the cardiovascular system that simulates physiological events, from membrane excitation and the contraction of a cardiac cell to heart mechanics and arterial blood hemodynamics. Using this model, we delineated the relationship between arterial BP or pulse wave velocity and LVH. Computed results were compared with existing clinical and experimental observations. To investigate the relationship between arterial hemodynamics and LVH, we performed a parametric study based on arterial wall stiffness, which was obtained in the model. Peak cellular stress of the left ventricle and systolic blood pressure (SBP) in the brachial and central arteries also increased; however, further increases were limited for higher arterial stiffness values. Interestingly, when we doubled the value of arterial stiffness from the baseline value, the percentage increase of SBP in the central artery was about 6.7% whereas that of the brachial artery was about 3.4%. It is suggested that SBP in the central artery is more critical for predicting LVH as compared with other blood pressure measurements.

  14. Dose-dependent headache response and dilatation of limb and extracranial arteries after three doses of 5-isosorbide-mononitrate

    DEFF Research Database (Denmark)

    Iversen, Helle Klingenberg; Nielsen, T H; Garre, K

    1992-01-01

    The aim of the present study was to compare the ability of different doses of isosorbide-5-mononitrate (5-ISMN) to cause dilatation of medium sized and small arteries, and to examine the intensity and duration of any headache produced. Ten healthy volunteers each received 3 doses of 5-ISMN...... and placebo on separate days. The diameters of the radial and superficial temporal arteries were repeatedly measured with high frequency ultrasound and pain was scored using a 10 point verbal scale. A clear dose-relationship was found for plasma concentrations and headache, and for changes in the diameter...... of the temporal artery, but not for the radial artery. It is concluded that headache after 5-ISMN is caused by arterial dilatation or by mechanisms responsible for the arterial dilatation. Ultrasound monitoring of arterial diameters is an important and sensitive tool in the evaluation of nitrates and other...

  15. BILATERAL DUPLICATION OF RENAL ARTERIES

    OpenAIRE

    Prajkta A Thete; Mehera Bhoir; M.V.Ambiye

    2014-01-01

    Routine dissection of a male cadaver revealed the presence of bilateral double renal arteries. On the right side the accessory renal artery originated from the abdominal aorta just above the main renal artery. On the left side the accessory renal artery originated from the abdominal aorta about 1 cm above the main renal artery. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, su...

  16. Initial isolated Takayasu`s arteritis of the right pulmonary artery: MR appearance

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, G. [Department of Radiology, CHU Michallon, J Fourier University, Grenoble, F-38 043 Grenoble Cedex (France); Defaye, P. [Department of Cardiology, CHU Michallon, J Fourier University, Grenoble, F-38 043 Grenoble Cedex (France); Thony, F. [Department of Radiology, CHU Michallon, J Fourier University, Grenoble, F-38 043 Grenoble Cedex (France); Ranchoup, Y. [Department of Radiology, CHU Michallon, J Fourier University, Grenoble, F-38 043 Grenoble Cedex (France); Coulomb, M. [Department of Radiology, CHU Michallon, J Fourier University, Grenoble, F-38 043 Grenoble Cedex (France)

    1996-08-01

    Takayasu`s arteritis involves the pulmonary artery tree in more than 50 % of the cases. Initial isolated involvement of the pulmonary artery by Takayasu`s arteritis, however, is very rare. We report the case of a 34-year-old white woman who presented a clinical and radiographic pattern that mimicked an acute pulmonary embolism with pulmonary infarction. Pulmonary angiography showed stenosis lesions and occlusion of the right pulmonary artery tree. Magnetic resonance imaging demonstrated thickening of the pulmonary artery wall leading to the correct diagnosis. (orig.). With 3 figs.

  17. Vascular wall stress during intravascular optical coherence tomography imaging

    Science.gov (United States)

    Sun, Cuiru; Yang, Victor

    2015-03-01

    Biomechanical properties of arterial wall is crucial for understanding the changes in the cardiovascular system. Catheters are used during intravascular optical coherence tomography (IVOCT) imaging. The presence of a catheter alters the flow field, pressure distribution and frictional resistance to flow in an artery. In this paper, we first study the transmural stress distribution of the catheterized vessel. COMSOL (COMSOL 4.4) was used to simulate the blood flow induced deformation in a catheterized vessel. Blood is modeled as an incompressible Newtonian fluid. Stress distribution from an three-layer vascular model with an eccentric catheter are simulated, which provides a general idea about the distribution of the displacement and the stress. Optical coherence elastography techniques were then applied to porcine carotid artery samples to look at the deformation status of the vascular wall during saline or water injection. Preliminary simulation results show nonuniform stress distribution in the circumferential direction of the eccentrically catheterized vascular model. Three strain rate methods were tested for intravascular OCE application. The tissue Doppler method has the potential to be further developed to image the vascular wall biomechnical properties in vivo. Although results in this study are not validated quantitatively, the experiments and methods may be valuable for intravascular OCE studies, which may provide important information for cardiovascular disease prevention, diagnosis and treatment.

  18. Wall shear stress distributions on stented patent ductus arteriosus

    Science.gov (United States)

    Kori, Mohamad Ikhwan; Jamalruhanordin, Fara Lyana; Taib, Ishkrizat; Mohammed, Akmal Nizam; Abdullah, Mohammad Kamil; Ariffin, Ahmad Mubarak Tajul; Osman, Kahar

    2017-04-01

    A formation of thrombosis due to hemodynamic conditions after the implantation of stent in patent ductus arteriosus (PDA) will derived the development of re-stenosis. The phenomenon of thrombosis formation is significantly related to the distribution of wall shear stress (WSS) on the arterial wall. Thus, the aims of this study is to investigate the distribution of WSS on the arterial wall after the insertion of stent. Three dimensional model of patent ductus arteriosus inserted with different types of commercial stent are modelled. Computational modelling is used to calculate the distributions of WSS on the arterial stented PDA. The hemodynamic parameters such as high WSS and WSSlow are considered in this study. The result shows that the stented PDA with Type III stent has better hemodynamic performance as compared to others stent. This model has the lowest distributions of WSSlow and also the WSS value more than 20 dyne/cm2. From the observed, the stented PDA with stent Type II showed the highest distributions area of WSS more than 20 dyne/cm2. This situation revealed that the high possibility of atherosclerosis to be developed. However, the highest distribution of WSSlow for stented PDA with stent Type II indicated that high possibility of thrombosis to be formed. In conclusion, the stented PDA model calculated with the lowest distributions of WSSlow and WSS value more than 20dyne/cm2 are considered to be performed well in stent hemodynamic performance as compared to other stents.

  19. Pulmonary artery catheter entrapment in cardiac surgery

    Directory of Open Access Journals (Sweden)

    Alsatli Raed

    2010-01-01

    Full Text Available A pulmonary artery catheter (PAC is an important tool in the preoperative cardiac management, and it provides measurements which helps in the patient management During open heart surgery the catheter tends to rest against the anterior lateral wall of the right atrium where the catheter may be caught by a suture in the cannulation for cardiopulmonary bypass. We describe a very rare complication which is inadvertent surgical suturing of the PAC to the inferior vena cava that necessitated reopening the chest, cutting, the suture and removing the catheter.

  20. A Review on Atherosclerotic Biology, Wall Stiffness, Physics of Elasticity, and Its Ultrasound-Based Measurement.

    Science.gov (United States)

    Patel, Anoop K; Suri, Harman S; Singh, Jaskaran; Kumar, Dinesh; Shafique, Shoaib; Nicolaides, Andrew; Jain, Sanjay K; Saba, Luca; Gupta, Ajay; Laird, John R; Giannopoulos, Argiris; Suri, Jasjit S

    2016-12-01

    Functional and structural changes in the common carotid artery are biomarkers for cardiovascular risk. Current methods for measuring functional changes include pulse wave velocity, compliance, distensibility, strain, stress, stiffness, and elasticity derived from arterial waveforms. The review is focused on the ultrasound-based carotid artery elasticity and stiffness measurements covering the physics of elasticity and linking it to biological evolution of arterial stiffness. The paper also presents evolution of plaque with a focus on the pathophysiologic cascade leading to arterial hardening. Using the concept of strain, and image-based elasticity, the paper then reviews the lumen diameter and carotid intima-media thickness measurements in combined temporal and spatial domains. Finally, the review presents the factors which influence the understanding of atherosclerotic disease formation and cardiovascular risk including arterial stiffness, tissue morphological characteristics, and image-based elasticity measurement.

  1. De novo cerebral arteriovenous malformation: Pink Floyd's song "Brick in the Wall" as a warning sign.

    Science.gov (United States)

    Ozsarac, Murat; Aksay, Ersin; Kiyan, Selahattin; Unek, Orkun; Gulec, F Feray

    2012-07-01

    Arteriovenous malformations are shunts between an artery and the venous system that lie within a nidus without an intervening capillary bed. These lesions are thought to be congenital, but recent reports have challenged this assumption. A 50-year-old man presented to the emergency department with a generalized tonic-clonic seizure. Before the onset of his seizure, he experienced a vivid auditory hallucination of his favorite song by the band Pink Floyd, "A Brick in the Wall." He had been diagnosed with epilepsy 25 years previously. On presentation, his neurological examination was normal, but a computed tomography scan of the brain revealed a large arteriovenous malformation (AVM) occupying the left temporal lobe. Upon more detailed questioning, he recalled that a brain angiogram had been performed 25 years before and was reported to be normal. Neurosurgery was not performed in view of the size of the malformation. The patient is being followed-up as an outpatient. AVMs may arise de novo and then spontaneously become symptomatic. Cerebral de novo AVM should be considered in the differential diagnosis in patients with complex auditory musical hallucinations or any new neuropsychiatric symptoms. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Moisture Research - Optimizing Wall Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Arena, Lois [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Mantha, Pallavi [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2013-05-01

    In this project, the Consortium for Advanced Residential Buildings (CARB) team evaluated several different configurations of wall assemblies to determine the accuracy of moisture modeling and make recommendations to ensure durable, efficient assemblies. WUFI and THERM were used to model the hygrothermal and heat transfer characteristics of these walls. Wall assemblies evaluated included code minimum walls using spray foam insulation and fiberglass batts, high R-value walls at least 12 in. thick (R-40 and R-60 assemblies), and brick walls with interior insulation.

  3. [Vascularization of the wall of the superficial veins. Anatomic study of the vasa vasorum].

    Science.gov (United States)

    Lefebvre, D; Lescalie, F

    1996-01-01

    The blood vessel wall is almost always nourished by two ways; from the blood stream itself and through the outer part of the wall by vasa vasorum. The aim of this study was to demonstrate that this kind of nutrition is also available for the venous wall and to define the distribution pattern in superficial venous walls. 50 long saphenous veins and 20 short saphenous veins latex or barium injections, dissections with magnifying glasses and microradiographies. Topographical evaluation of the origin of vasa vasorum. The results showed that vasa vasorum originated from perforating arteries coming from several levels and getting a lot of anastomosis. We showed that the main sources for the long saphenous vein are the external pudendal artery and descending artery of the knee and for the short saphenous vein, the short saphenous vein artery. In thrombosis and varicose veins, the vasa were strongly altered. This study outlines the fact that superficial veins are supplied by arterial and venous vasa vasorum, and the role of vasa vasorum must be considered when questioning the pathogenesis of varicose and post thrombotic disease.

  4. High-resolution intracranial vessel wall MRI in an elderly asymptomatic population: comparison of 3T and 7T

    Energy Technology Data Exchange (ETDEWEB)

    Harteveld, Anita A.; Kolk, Anja G. van der; Dieleman, Nikki; Siero, Jeroen C.W.; Luijten, Peter R.; Zwanenburg, Jaco J.M.; Hendrikse, Jeroen [University Medical Center Utrecht, Department of Radiology, Postbox 85500, Utrecht (Netherlands); Worp, H.B. van der; Frijns, Catharina J.M. [University Medical Center Utrecht, Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, Utrecht (Netherlands); Kuijf, Hugo J. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands)

    2017-04-15

    Several intracranial vessel wall sequences have been described in recent literature, with either 3-T or 7-T magnetic resonance imaging (MRI). In the current study, we compared 3-T and 7-T MRI in visualising both the intracranial arterial vessel wall and vessel wall lesions. Twenty-one elderly asymptomatic volunteers were scanned by 3-T and 7-T MRI with an intracranial vessel wall sequence, both before and after contrast administration. Two raters scored image quality, and presence and characteristics of vessel wall lesions. Vessel wall visibility was equal or significantly better at 7 T for the studied arterial segments, even though there were more artefacts hampering assessment. The better visualisation of the vessel wall at 7 T was most prominent in the proximal anterior cerebral circulation and the posterior cerebral artery. In the studied elderly asymptomatic population, 48 vessel-wall lesions were identified at 3 T, of which 7 showed enhancement. At 7 T, 79 lesions were identified, of which 29 showed enhancement. Seventy-one percent of all 3-T lesions and 59 % of all 7-T lesions were also seen at the other field strength. Despite the large variability in detected lesions at both field strengths, we believe 7-T MRI has the highest potential to identify the total burden of intracranial vessel wall lesions. (orig.)

  5. Passive biaxial mechanical response of aged human iliac arteries.

    Science.gov (United States)

    Schulze-Bauer, Christian A J; Mörth, Christian; Holzapfel, Gerhard A

    2003-06-01

    Inflation and extension tests of arteries are essential for the understanding of arterial wall mechanics. Data for such tests of human arteries are rare. At autopsy we harvested 10 non-diseased external iliac arteries of aged subjects (52-87 yrs). Structural homogeneity was ensured by means of ultrasound imaging, and anamneses of patients were recorded. We measured the axial in situ stretches, load-free geometries and opening angles. Passive biaxial mechanical responses of preconditioned cylindrical specimens were studied in 37 degrees C calcium-free Tyrode solution under quasistatic loading conditions. Specimens were subjected to pressure cycles varying from 0 to 33.3 kPa (250 mmHg) at nine fixed axial loads, varying from 0 to 9.90N. For the description of the load-deformation behavior we employed five "two-dimensional" orthotropic strain-energy functions frequently used in arterial wall mechanics. The associated constitutive models were compared in regard to their ability of representing the experimental data. Histology showed that the arteries were of the muscular type. In contrast to animal arteries they exhibited intimal layers of considerable thickness. The average ratio of wall thickness to outer diameter was 7.7, which is much less than observed for common animal arteries. We found a clear correlation between age and the axial in situ stretch lambda is (r = -0.72, P = 0.03), and between age and distensibility of specimens, i.e. aged specimens are less distensible. Axial in situ stretches were clearly smaller (1.07 +/- 0.09, mean +/- SD) than in animal arteries. For one specimen lambda is was even smaller than 1.0, i.e. the vessel elongated axially upon excision. The nonlinear and anisotropic load-deformation behavior showed small hystereses. For the majority of specimens