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Sample records for ischemic penumbra predicts

  1. Use of susceptibility-weighted imaging in assessing ischemic penumbra

    Science.gov (United States)

    Wu, Xiujuan; Luo, Song; Wang, Ying; Chen, Yang; Liu, Jun; Bai, Jing; Feng, Jiachun; Zhang, Hongliang

    2017-01-01

    Abstract Rationale: The ischemic penumbra assessment is essential for the subsequent therapy and prediction of evolution in patients with acute ischemic infraction. Although controversial as a perfect equivalence to penumbra, perfusion-weighted imaging (PWI)-diffusion-weighted imaging (DWI) mismatch may predict the response to thrombolysis. Due to the reliance of PWI on contrast agents, noninvasive alternatives remain an unmet need. Patient concerns: We reported a 65-year-old man complained of paroxysmal hemiplegia of his right limbs and anepia for 2 days, whereas the symptoms lasted for about 12 hours when he admitted to the hospital. Diagnosis: We diagnosed it as acute ischemic stroke caused by the left middle cerebral artery stenosis. Interventions: Susceptibility-weighted imaging (SWI), multimodal magnetic resonance imaging (MRI) work-up which includes conventional MRI sequences (T1WI, T2WI, and FLAIR), DWI, PWI. Outcomes: His DWI-SWI mismatch was comparable to that of DWI-PWI at admission, suggesting that DWI-SWI could predict ischemic penumbra in patient with acute infarction. He refused the digital subtraction angiography examination or stenting, and he was treated with aspirin, atorvastain, and supportive treatment. The patient received a reexamination of the conventional MRI and SWI 11 days later. Expansion of the infarction in the affected MCA territory resulted from the penumbra indicated by the mismatch between DWI-SWI. Lessons: SWI can be used as a noninvasive alternative to evaluate the ischemic penumbra. Besides, SWI can provide perfusion information comparable to PWI and SWI is sufficient to identify occlusive arteries. PMID:28178170

  2. Rescuing the ischemic penumbra: Our experience

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    Milosavljević Tamara

    2013-12-01

    Full Text Available Objectives: Over one million strokes per year are occurring in Europe. Brain stroke is one of the most important death and disability causes in Europe and USA. The main role of perfusion is to determine the border of insult core and ischemic penumbra. Penumbra can be saved with thrombolytic therapy but core have irreversible injuries and represent death of brain cells. Aim: to determine the role of CT brain perfusion in cases of acute brain stroke and following thrombolytic therapy. Methods: We examined 64 patients with acute brain stroke who received thrombolytic therapy after that. All patients were examining on 16 MDCT with 50 ml of iodine contrast agent following the standard procedure for CT perfusion. Patients were 34 male and 30 female with middle age of 64 years. MRI was made after thrombolytic therapy and compare with perfusion results before therapy. Results: Using an artery and a vein as reference three parameters were measured - blood flow (CBF, blood volume (CBV and mean transit time (MTT, for each patient. Hemorrhagic was find in 9 (14.01% patients after thrombolytic therapy. 4 (6.25% other patients develop new stroke of same but mostly other side of brain. 8 (12.50% more patients finished lethally. From other 42 patients with thrombolytic therapy we can positively say that in 31 (48.44% patients penumbra was rescued. For other 11 (17.19% stroke was same size like firstly involved core and penumbra but not bigger. Conclusion: CT perfusion plays major role by showing a curable parts of tissue in brain strokes.

  3. Recurrent Spontaneous Spreading Depolarizations Facilitate Acute Dendritic Injury in the Ischemic Penumbra

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    Risher, W Christopher; Ard, Deborah; Yuan, Jianghe; Kirov, Sergei A.

    2010-01-01

    Spontaneous spreading depolarizations (SDs) occur in the penumbra surrounding ischemic core. These SDs, often referred to as peri-infarct depolarizations, cause vasoconstriction and recruitment of the penumbra into the ischemic core in the critical first hours after focal ischemic stroke; however, the real-time spatiotemporal dynamics of SD-induced injury to synaptic circuitry in the penumbra remain unknown. A modified cortical photothrombosis model was used to produce a square-shaped lesion ...

  4. Whole-Brain CT Perfusion to Quantify Acute Ischemic Penumbra and Core.

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    Lin, Longting; Bivard, Andrew; Krishnamurthy, Venkatesh; Levi, Christopher R; Parsons, Mark W

    2016-06-01

    Purpose To validate the use of perfusion computed tomography (CT) with whole-brain coverage to measure the ischemic penumbra and core and to compare its performance to that of limited-coverage perfusion CT. Materials and Methods Institutional ethics committee approval and informed consent were obtained. Patients (n = 296) who underwent 320-detector CT perfusion within 6 hours of the onset of ischemic stroke were studied. First, the ischemic volume at CT perfusion was compared with the penumbra and core reference values at magnetic resonance (MR) imaging to derive CT perfusion penumbra and core thresholds. Second, the thresholds were tested in a different group of patients to predict the final infarction at diffusion-weighted imaging 24 hours after CT perfusion. Third, the change in ischemic volume delineated by the optimal penumbra and core threshold was determined as the brain coverage was gradually reduced from 160 mm to 20 mm. The Wilcoxon signed-rank test, concordance correlation coefficient (CCC), and analysis of variance were used for the first, second, and third steps, respectively. Results CT perfusion at penumbra and core thresholds resulted in the least volumetric difference from MR imaging reference values with delay times greater than 3 seconds and delay-corrected cerebral blood flow of less than 30% (P = .34 and .33, respectively). When the thresholds were applied to the new group of patients, prediction of the final infarction was allowed with delay times greater than 3 seconds in patients with no recanalization of the occluded artery (CCC, 0.96 [95% confidence interval: 0.92, 0.98]) and with delay-corrected cerebral blood flow less than 30% in patients with complete recanalization (CCC, 0.91 [95% confidence interval: 0.83, 0.95]). However, the ischemic volume with a delay time greater than 3 seconds was underestimated when the brain coverage was reduced to 80 mm (P = .04) and the core volume measured as cerebral blood flow less than 30% was

  5. Value of perfusion computed tomography in acute ischemic stroke: diagnosis of infarct core and penumbra.

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    Pan, Jiawei; Zhang, Jun; Huang, Weiyuan; Cheng, Xin; Ling, Yifeng; Dong, Qiang; Geng, Daoying

    2013-01-01

    This study aimed to perform an evaluation of 4 perfusion computed tomographic (PCT) parameters (relative cerebral blood flow, cerebral blood volume, mean transit time [MTT], and delay time [DT]) in a series of patients with acute ischemic stroke to find optimal parameters to predict infarct core and penumbra. Twenty-six patients with symptoms suggesting stroke less than 7 hours from onset were enrolled in this study. They all underwent admission and 24-hour PCT and a 24-hour diffusion-weighted imaging. Perfusion computed tomographic maps were assessed for relative reduced cerebral blood flow and cerebral blood volume and increased MTT and DT. Receiver operating characteristic curve analysis was performed to locate the optimal threshold for each parameter, using diffusion-weighted imaging as the gold standard. The PCT parameter that most accurately describes the penumbra is the relative MTT of 150% or greater (area under the curve, 0.827; 95% confidence interval, 0.826-0.827), whereas the parameter that most accurately describes the infarct core is the relative DT of + 2.0 seconds or greater (area under the curve, 0.879; 95% confidence interval, 0.878-0.879). The optimal parameters to define the infarct core and the penumbra are relative DT (≥+ 2.0 seconds) and relative MTT (≥ 150%).

  6. Altered resting-state FMRI signals in acute stroke patients with ischemic penumbra.

    Directory of Open Access Journals (Sweden)

    Yuan-Hsiung Tsai

    Full Text Available Identifying the ischemic penumbra in acute stroke subjects is important for the clinical decision making process. The aim of this study was to use resting-state functional magnetic resonance singal (fMRI to investigate the change in the amplitude of low-frequency fluctuations (ALFF of these subjects in three different subsections of acute stroke regions: the infarct core tissue, the penumbra tissue, and the normal brain tissue. Another aim of this study was to test the feasilbility of consistently detecting the penumbra region of the brain through ALFF analysis.Sixteen subjects with first-ever acute ischemic stroke were scanned within 27 hours of the onset of stroke using magnetic resonance imaging. The core of infarct regions and penumbra regions were determined by diffusion and perfusion-weighted imaging respectively. The ALFF were measured from resting-state blood oxygen level dependent (BOLD fMRI scans. The averaged relative ALFF value of each regions were correlated with the time after the onset of stroke.Relative ALFF values were significantly different in the infarct core tissue, penumbra tissue and normal brain tissue. The locations of lesions in the ALFF maps did not match perfectly with diffusion and perfusion-weighted imagings; however, these maps provide a contrast that can be used to differentiate between penumbra brain tissue and normal brain tissue. Significant correlations between time after stroke onset and the relative ALFF values were present in the penumbra tissue but not in the infarct core and normal brain tissue.Preliminary results from this study suggest that the ALFF reflects the underlying neurovascular activity and has a great potential to estimate the brain tissue viability after ischemia. Results also show that the ALFF may contribute to acute stroke imaging for thrombolytic or neuroprotective therapies.

  7. Delay-sensitive and delay-insensitive deconvolution perfusion-CT: similar ischemic core and penumbra volumes if appropriate threshold selected for each

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    Man, Fengyuan [Capital Medical University, Department of Radiology, Beijing Tongren Hospital, Beijing (China); University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States); Patrie, James T.; Xin, Wenjun [University of Virginia, Department of Public Health Sciences, Charlottesville, VA (United States); Zhu, Guangming [University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States); Military General Hospital of Beijing PLA, Department of Neurology, Beijing (China); Hou, Qinghua [University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States); The Second Affiliated Hospital of Guangzhou Medical University, Department of Neurology, Guangzhou (China); Michel, Patrik; Eskandari, Ashraf [Centre Hospitalier Universitaire Vaudois, Department of Neurology, Lausanne (Switzerland); Jovin, Tudor [University of Pittsburgh, Department of Neurology, Pittsburgh, PA (United States); Xian, Junfang; Wang, Zhenchang [Capital Medical University, Department of Radiology, Beijing Tongren Hospital, Beijing (China); Wintermark, Max [University of Virginia, Department of Radiology, Neuroradiology Division, Charlottesville, VA (United States); Centre Hospitalier Universitaire Vaudois, Department of Radiology, Lausanne (Switzerland); Stanford University, Department of Radiology, Neuroradiology Division, Stanford, CA (United States)

    2015-03-07

    Perfusion-CT (PCT) processing involves deconvolution, a mathematical operation that computes the perfusion parameters from the PCT time density curves and an arterial curve. Delay-sensitive deconvolution does not correct for arrival delay of contrast, whereas delay-insensitive deconvolution does. The goal of this study was to compare delay-sensitive and delay-insensitive deconvolution PCT in terms of delineation of the ischemic core and penumbra. We retrospectively identified 100 patients with acute ischemic stroke who underwent admission PCT and CT angiography (CTA), a follow-up vascular study to determine recanalization status, and a follow-up noncontrast head CT (NCT) or MRI to calculate final infarct volume. PCT datasets were processed twice, once using delay-sensitive deconvolution and once using delay-insensitive deconvolution. Regions of interest (ROIs) were drawn, and cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) in these ROIs were recorded and compared. Volume and geographic distribution of ischemic core and penumbra using both deconvolution methods were also recorded and compared. MTT and CBF values are affected by the deconvolution method used (p < 0.05), while CBV values remain unchanged. Optimal thresholds to delineate ischemic core and penumbra are different for delay-sensitive (145 % MTT, CBV 2 ml x 100 g{sup -1} x min{sup -1}) and delay-insensitive deconvolution (135 % MTT, CBV 2 ml x 100 g{sup -1} x min{sup -1} for delay-insensitive deconvolution). When applying these different thresholds, however, the predicted ischemic core (p = 0.366) and penumbra (p = 0.405) were similar with both methods. Both delay-sensitive and delay-insensitive deconvolution methods are appropriate for PCT processing in acute ischemic stroke patients. The predicted ischemic core and penumbra are similar with both methods when using different sets of thresholds, specific for each deconvolution method. (orig.)

  8. Learning and memory changes in rats following exogenous human hepatocyte growth factor gene injection into cerebral ischemic penumbra

    Institute of Scientific and Technical Information of China (English)

    Zhijun You; Yong Liu; Jianye Yang; Qingping Jiang

    2011-01-01

    Human hepatocyte growth factor can be used to treat cerebral infarction, administered by lateral ventricular, cerebellomedullary cistern or subarachnoid injections. However, the target gene expression product is scarcely found in the ischemic penumbra, but extensively distributes in other regions, increasing the risks of gene therapy. The present study directly transfected hepatocyte growth factor gene into the ischemic penumbra of rats with transient middle cerebral artery occlusion. Immunohistochemical analysis revealed that infarct volume was significantly decreased, hepatocyte growth factor protein expression level and vessel quantity in the ischemic penumbra were significantly increased, and learning and memory were significantly improved.

  9. The ischemic penumbra: correlates in imaging and implications for treatment of ischemic stroke. The Johann Jacob Wepfer award 2011.

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    Heiss, Wolf-Dieter

    2011-01-01

    The concept of the ischemic penumbra was formulated 30 years ago based on experiments in animal models showing functional impairment and electrophysiological disturbances with decreasing flow to the brain below defined values (the threshold for function) and irreversible tissue damage with the blood supply further decreased (the threshold for infarction). The perfusion range between these thresholds was termed 'penumbra', and restitution of flow above the functional threshold was able to reverse the deficits without permanent damage. However, in further experiments, the dependency of the development of irreversible lesions on the interaction of the severity and duration of critically reduced blood flow was established - proving that the lower the flow, the shorter the time for efficient reperfusion. Therefore, infarction develops from the core of ischemia to the areas of less severe hypoperfusion. The propagation of irreversible tissue damage is characterized by a complex cascade of interconnected electrophysiological, molecular, metabolic and perfusional disturbances. Waves of depolarizations, the peri-infarct spreading depression-like depolarizations, inducing activation of ion pumps and liberation of excitatory transmitters, have dramatic consequences as drastically increased metabolic demand cannot be satisfied in regions with critically reduced blood supply. The translation of experimental concept into the basis for efficient treatment of stroke requires non-invasive methods by which regional flow and energy metabolism can be repeatedly investigated to demonstrate penumbra tissue that can benefit from therapeutic interventions. Positron emission tomography (PET) allows the quantification of regional cerebral blood flow, the regional metabolic rate for oxygen and the regional oxygen extraction fraction. From these variables, clear definitions of irreversible tissue damage and critically perfused but potentially salvageable tissue (i.e. the penumbra) can be

  10. CLINICAL STUDY OF ISCHEMIC PENUMBRA REGION IN BRAIN ELECTRICAL ACTIVITY MAPPING

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    Liu Qingrui; Liu Mingshun; Gu Lanjie; Mei Fengjun

    2000-01-01

    Department of Neurology, Fourth Affiliated Hospital. Hebei Medical University, Shijiazhuang ABSTRACT OBJETIVE To study features and clinical usage of ischemic penumbra region(IPR) in brain electrical activity mapping(BEAM).BACKGROUND To explore the functional improvement index of IPR untraumaticly. METH0DS 69 patients with acute cerebral infarction were divided into two groups according to different therapeutic time window--early treatment group( 32 cases, treatment in 12 hours)and contral group (37 cases, treatment in 12-72 hours).They were analysed in BEAM pre-and post-treatment Results: BEAM showed that the power of infarcted core was decreased and IPR became smaller in slow waves significantly after treatment in early treatment group and this change was in good agreement with improvement of clinical functions and SPECT DISCUSSION The key to treat acute cerebral infarction was to improve functions of IPR as 8oos as possible, BEAM could show the location and size of IPR. CONCLUSION BEAM was one of important index in evaluating the function of IPR.

  11. Blood flow and vascular reactivity in collaterally perfused brain tissue. Evidence of an ischemic penumbra in patients with acute stroke

    DEFF Research Database (Denmark)

    Olsen, T S; Larsen, B; Herning, M;

    1983-01-01

    ischemic low flow areas were a constant finding in the collaterally perfused tissue. In 6 of the patients, the collaterally perfused part of the brain had low flow values comparable to those of an "ischemic penumbra" (viable, but functionally depressed brain tissue due to inadequate perfusion......In a group of 48 patients with completed stroke, 8 patients had viable collaterally perfused brain tissue which was accessible for rCBF recordings with a two dimensional technique. All 8 had deep subcortical infarcts on CT-scan, and angiographic occlusion of the arteries normally supplying...... the infarcted territory. The brain tissue overlying the deep infarcts appeared normal on CT-scan and was supplied by collateral circulation. rCBF was measured in all within 72 hours after the stroke. The intra-carotid Xe-133 injection method and a 254 multidetector camera were used to study rCBF. Relatively...

  12. The role of the cerebral capillaries in acute ischemic stroke: the extended penumbra model.

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    Østergaard, Leif; Jespersen, Sune Nørhøj; Mouridsen, Kim; Mikkelsen, Irene Klærke; Jonsdottír, Kristjana Ýr; Tietze, Anna; Blicher, Jakob Udby; Aamand, Rasmus; Hjort, Niels; Iversen, Nina Kerting; Cai, Changsi; Hougaard, Kristina Dupont; Simonsen, Claus Z; Von Weitzel-Mudersbach, Paul; Modrau, Boris; Nagenthiraja, Kartheeban; Riisgaard Ribe, Lars; Hansen, Mikkel Bo; Bekke, Susanne Lise; Dahlman, Martin Gervais; Puig, Josep; Pedraza, Salvador; Serena, Joaquín; Cho, Tae-Hee; Siemonsen, Susanne; Thomalla, Götz; Fiehler, Jens; Nighoghossian, Norbert; Andersen, Grethe

    2013-05-01

    The pathophysiology of cerebral ischemia is traditionally understood in relation to reductions in cerebral blood flow (CBF). However, a recent reanalysis of the flow-diffusion equation shows that increased capillary transit time heterogeneity (CTTH) can reduce the oxygen extraction efficacy in brain tissue for a given CBF. Changes in capillary morphology are typical of conditions predisposing to stroke and of experimental ischemia. Changes in capillary flow patterns have been observed by direct microscopy in animal models of ischemia and by indirect methods in humans stroke, but their metabolic significance remain unclear. We modeled the effects of progressive increases in CTTH on the way in which brain tissue can secure sufficient oxygen to meet its metabolic needs. Our analysis predicts that as CTTH increases, CBF responses to functional activation and to vasodilators must be suppressed to maintain sufficient tissue oxygenation. Reductions in CBF, increases in CTTH, and combinations thereof can seemingly trigger a critical lack of oxygen in brain tissue, and the restoration of capillary perfusion patterns therefore appears to be crucial for the restoration of the tissue oxygenation after ischemic episodes. In this review, we discuss the possible implications of these findings for the prevention, diagnosis, and treatment of acute stroke.

  13. 脑梗塞患者缺血半暗带的PET检查%PET Measurement of Ischemic Penumbra in Patients with Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    刘建辉

    2001-01-01

    The role of positron emission tomography(PET) for measurement of ischemic penumbra in acute ischemic cerebrovascular diseases are reviewed.With PET,not only the location and size of penumbra can be discovered in the early stage,but also the existent status of the living tissue and its prognosis can be judeged.PET is a new,effective measuring means in the screening of the candidates for early therapy in ischemic cerebrovascular diseases and clinical study of ischemia penumbra.%对正电子发射计算机断层显像(Positron emission tomography,PET)在缺血性脑血管病早期缺血半暗带判定中的作用进行了综述。PET不但能早期发现半暗带的部位及大小,而且可以判定其中存活组织的生存状态,并能预测其转归,为缺血性脑血管病早期治疗对象的筛选及缺血半暗带的研究提供了一种新的、有效的检查手段。

  14. Differentiation of the infarct core from ischemic penumbra within the first 4.5 hours, using diffusion tensor imaging-derived metrics: A rat model

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    Kuo, Duen Pang [Dept. of Electrical Engineering, National Taiwan University, Taipei (China); Lu, Chia Feng [Research Center of Translational Imaging, College of Medicine, Taipei Medical University, Taipei (China); Chen, Yung Chieh [Dept. of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei (China); Liou, Michelle [Institute of Statistical Science, Academia Sinica, Taipei (China); Chung, Hsiao Wen [Graduate Institute of Biomedical Electrics and Bioinformatics, National Taiwan University, Taipei (China)

    2017-04-15

    To investigate whether the diffusion tensor imaging-derived metrics are capable of differentiating the ischemic penumbra (IP) from the infarct core (IC), and determining stroke onset within the first 4.5 hours. All procedures were approved by the local animal care committee. Eight of the eleven rats having permanent middle cerebral artery occlusion were included for analyses. Using a 7 tesla magnetic resonance system, the relative cerebral blood flow and apparent diffusion coefficient maps were generated to define IP and IC, half hour after surgery and then every hour, up to 6.5 hours. Relative fractional anisotropy, pure anisotropy (rq) and diffusion magnitude (rL) maps were obtained. One-way analysis of variance, receiver operating characteristic curve and nonlinear regression analyses were performed. The evolutions of tensor metrics were different in ischemic regions (IC and IP) and topographic subtypes (cortical, subcortical gray matter, and white matter). The rL had a significant drop of 40% at 0.5 hour, and remained stagnant up to 6.5 hours. Significant differences (p < 0.05) in rL values were found between IP, IC, and normal tissue for all topographic subtypes. Optimal rL threshold in discriminating IP from IC was about -29%. The evolution of rq showed an exponential decrease in cortical IC, from -26.9% to -47.6%; an rq reduction smaller than 44.6% can be used to predict an acute stroke onset in less than 4.5 hours. Diffusion tensor metrics may potentially help discriminate IP from IC and determine the acute stroke age within the therapeutic time window.

  15. Differentiation of the Infarct Core from Ischemic Penumbra within the First 4.5 Hours, Using Diffusion Tensor Imaging-Derived Metrics: A Rat Model

    Science.gov (United States)

    Kuo, Duen-Pang; Lu, Chia-Feng; Liou, Michelle; Chen, Yung-Chieh; Chung, Hsiao-Wen

    2017-01-01

    Objective To investigate whether the diffusion tensor imaging-derived metrics are capable of differentiating the ischemic penumbra (IP) from the infarct core (IC), and determining stroke onset within the first 4.5 hours. Materials and Methods All procedures were approved by the local animal care committee. Eight of the eleven rats having permanent middle cerebral artery occlusion were included for analyses. Using a 7 tesla magnetic resonance system, the relative cerebral blood flow and apparent diffusion coefficient maps were generated to define IP and IC, half hour after surgery and then every hour, up to 6.5 hours. Relative fractional anisotropy, pure anisotropy (rq) and diffusion magnitude (rL) maps were obtained. One-way analysis of variance, receiver operating characteristic curve and nonlinear regression analyses were performed. Results The evolutions of tensor metrics were different in ischemic regions (IC and IP) and topographic subtypes (cortical, subcortical gray matter, and white matter). The rL had a significant drop of 40% at 0.5 hour, and remained stagnant up to 6.5 hours. Significant differences (p < 0.05) in rL values were found between IP, IC, and normal tissue for all topographic subtypes. Optimal rL threshold in discriminating IP from IC was about -29%. The evolution of rq showed an exponential decrease in cortical IC, from -26.9% to -47.6%; an rq reduction smaller than 44.6% can be used to predict an acute stroke onset in less than 4.5 hours. Conclusion Diffusion tensor metrics may potentially help discriminate IP from IC and determine the acute stroke age within the therapeutic time window. PMID:28246507

  16. A mismatch between the abnormalities in diffusion- and susceptibility-weighted magnetic resonance imaging may represent an acute ischemic penumbra with misery perfusion.

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    Fujioka, Masayuki; Okuchi, Kazuo; Iwamura, Asami; Taoka, Toshiaki; Siesjö, Bo K

    2013-11-01

    Susceptibility-weighted imaging (SWI) has recently attracted attention for its ability to investigate acute stroke pathophysiology. SWI detects an increased ratio of deoxyhemoglobin to oxyhemoglobin in cerebral venous compartments, which can illustrate cerebral misery perfusion with a compensatory increase of oxygen extraction fraction in the hypoperfused brain. In this study we make the first case report of blunt cervical trauma leading to a stroke, demonstrating the disparity between diffusion-weighted imaging (DWI) and SWI changes, or DWI-SWI mismatch, in the acute ischemic brain. The area of mismatch between a smaller DWI cytotoxic edema and a larger SWI misery perfusion in our patient matured into a complete infarction with time. The DWI-SWI mismatch may signify the presence of an ischemic penumbra, and provide information about viability of the brain tissue at risk of potential infarction if without early reperfusion.

  17. Assessment of ischemic penumbra in patients with hyperacute stroke using amide proton transfer (APT) chemical exchange saturation transfer (CEST) MRI.

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    Tietze, Anna; Blicher, Jakob; Mikkelsen, Irene Klaerke; Østergaard, Leif; Strother, Megan K; Smith, Seth A; Donahue, Manus J

    2014-02-01

    Chemical exchange saturation transfer (CEST)-derived, pH-weighted, amide proton transfer (APT) MRI has shown promise in animal studies for the prediction of infarction risk in ischemic tissue. Here, APT MRI was translated to patients with acute stroke (1-24 h post-symptom onset), and assessments of APT contrast, perfusion, diffusion, disability and final infarct volume (23-92 days post-stroke) are reported. Healthy volunteers (n = 5) and patients (n = 10) with acute onset of symptoms (0-4 h, n = 7; uncertain onset diffusion- and perfusion-weighted MRI, fluid-attenuated inversion recovery (FLAIR) and CEST. Traditional asymmetry and a Lorentzian-based APT index were calculated in the infarct core, at-risk tissue (time-to-peak, TTP; lengthening) and final infarct volume. On average (mean ± standard deviation), control white matter APT values (asymmetry, 0.019 ± 0.005; Lorentzian, 0.045 ± 0.006) were not significantly different (p > 0.05) from APT values in normal-appearing white matter (NAWM) of patients (asymmetry, 0.022 ± 0.003; Lorentzian, 0.048 ± 0.003); however, ischemic regions in patients showed reduced (p = 0.03) APT effects compared with NAWM. Representative cases are presented, whereby the APT contrast is compared quantitatively with contrast from other imaging modalities. The findings vary between patients; in some patients, a trend for a reduction in the APT signal in the final infarct region compared with at-risk tissue was observed, consistent with tissue acidosis. However, in other patients, no relationship was observed in the infarct core and final infarct volume. Larger clinical studies, in combination with focused efforts on sequence development at clinically available field strengths (e.g. 3.0 T), are necessary to fully understand the potential of APT imaging for guiding the hyperacute management of patients.

  18. Transplanted bone marrow stem cells relocate to infarct penumbra and co-express endogenous proliferative and immature neuronal markers in a mouse model of ischemic cerebral stroke

    Directory of Open Access Journals (Sweden)

    Liu Wei

    2010-10-01

    Full Text Available Abstract Background Several studies demonstrate that neurogenesis may be induced or activated following vascular insults, which may be important for neuronal regeneration and functional recovery. Understanding the cellular mechanism underlying stroke-associated neurogenesis is of neurobiological as well as neurological/clinical relevance. The present study attempted to explore potential homing and early development of transplanted bone marrow stem cells in mouse forebrain after focal occlusion of the middle cerebral artery, an experimental model of ischemic stroke. Results Bone marrow stem cells isolated from donor mice were confirmed by analysis of surface antigen profile, and were pre-labeled with a lipophilic fluorescent dye PKH26, and subsequently transfused into recipient mice with middle cerebral artery coagulation. A large number of PKH26-labeled cells were detected surrounding the infarct site, most of which colocalized with immunolabelings for the proliferating cell nuclear antigen (PCNA and some also colocalized with the immature neuronal marker doublecortin (DCX during 1-2 weeks after the bone marrow cells transfusion. Conclusions The present study shows that transplanted bone morrow cells largely relocate to the infarct penumbra in ischemic mouse cerebrum. These transplanted bone marrow cells appear to undergo a process of in situ proliferation and develop into putative cortical interneurons during the early phase of experimental vascular injury.

  19. F-18 fluoromisonidazole PET predicts early lesion progression in acute ischemic stroke patients

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    Lee, G. H.; Kim, J. S.; Oh, S. J.; Cho, A. H.; Cho, K. H.; Kang, D. H.; Kim, J. S.; Kwon, S. E. [Asan Medical Center, Seoul (Korea, Republic of)

    2007-07-01

    F-18 fluoromisonidazole (FMISO) PET has been known to image viable hypoxic area. We performed this study to define whether FMISO PET can reveal ischemic penumbra of acute ischemic stroke. We prospectively selected acute ischemic stroke patients with large diffusion-perfusion mismatch due to occlusion of MCA or ICA on MRI among patients who visited emergency room within 24 hours after stroke onset. FMISO PET and diffusion weighted MR image (DWI) performed within 48 hours after initial MRI. We excluded the patients who performed any reperfusion procedure. To define the final infarcted area, DWI was performed again 2 days after PET scan. Brain FMISO PET was performed 3 hour after the injection of FMISO (370 MBq). FMISO PET was assessed by visual and quantitative analysis. The extent of abnormally increased FMISO uptake was automatically calculated by the number and size of voxels having higher count than upper 3SD of the mean count of contralateral normal hemisphere. We compared the extent of abnormal FMISO uptake area with the change of the extent of ischemic lesions on DWI. Fifteen patients were enrolled in this study. Ten of these patients showed abnormally increased FMISO uptake in peri-infarct area. Ischemic lesion size on follow-up DWI significantly increased in all patients with abnormally increased FMISO uptake except one patient of whom the MCA spontaneously recanalized on follow up angiogram. Ischemic lesions on DWI increased in only one of five patients without abnormally increased FMISO uptake. The extent of abnormally increased FMISO uptake area was positively correlated with infarct size progression on DWI (Spearman correlation coefficient = 0.757, p<0.01). FMISO uptake specifically and sensitively predicted early lesion progression in acute ischemic stroke patients with large diffusion-perfusion mismatch. Therefore, FMISO PET will be a good indicator of the revascularization or reperfusion procedure for acute ischemic stroke by defining ischemic

  20. Comparisons of Apparent Diffusion Coefficient Values in Penumbra, Infarct, and Normal Brain Regions in Acute Ischemic Stroke: Confirmatory Data Using Bootstrap Confidence Intervals, Analysis of Variance, and Analysis of Means.

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    Lopez-Mejia, Mariana; Roldan-Valadez, Ernesto

    2016-03-01

    There is no consensus about apparent diffusion coefficient (ADC) values in acute stroke regions that could be used by clinicians in a day-to-day clinical practice; regional measures using confidence intervals (CIs) and a graphic representation of means are scarce in the literature. Our aim in this study was to compare ADC values in infarct, penumbra, and normal brain regions in patients with acute ischemic stroke (AIS). This is a retrospective study of 100 magnetic resonance imaging data sets from AIS patients. ADC values were measured in the infarct, penumbra, and normal regions. Three hundred measurements underwent 1-way analysis of variance, analysis of means, and calculation of 95% and 84% CIs. There was a statistically significant difference at the P level less than .025 in ADC values for the 3 regions (F[2, 297] = 168.039, P ≤ .001), with no overlap of the CIs for the means among the regions: normal brain (mean [M] = .847, standard deviation [SD] = .103, 95% CI: .825-.866), infarct (M = .533, SD = .157, 95% CI: .501-.563), and penumbra (M = .764, SD = .110, 95% CI: .740-.787). ADC values might be used as reference data in acute stroke-specific populations; CIs would provide radiologists and clinicians with additional quantitative tools to evaluate penumbra, infarct, and normal brain tissue and to tailor follow-up and treatment options for selected patients. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  1. Using the knowledge of penumbra with a trick simulation

    CERN Document Server

    Bülbül, Mustafa Şahin

    2016-01-01

    The study is about a basic shadow experiment, which was enriched with a simulation to understand the reasoning of participants when we use a trick. Two light sources create an umbra and penumbra behind the objects. With this experiment, we asked what would happen when the penumbras interact. Most of the participants predicted the correct solution, that there should be an umbra. Some of the participants choose wrong alternative, and explained in terms of the structure of penumbra.

  2. Ischaemic penumbra: highlights.

    Science.gov (United States)

    Pestalozza, Isabella F; Di Legge, Silvia; Calabresi, Marco; Lenzi, Gian Luigi

    2002-01-01

    The ischaemic penumbra was described for the first time in the late 1970s as a ring of hypoperfused zone surrounding the region of complete infarction. The penumbral zone is a functionally silent tissue which is able to regain its function if promptly reperfused. This implies that the ischaemic penumbra is not a static but a "dynamic" and "time-dependent" concept. In this paper we describe the role of neuroimmaging tecniques such as single photon emission tomography (SPET), positron emission tomography (PET), and diffusion-weighted and perfusion-weighted magnetic resonance imaging (DWI and PWI) in the study of ischaemic penumbra. These functional imaging techniques have the advantage of giving "in vivo" quantitative estimate of cerebral blood flow (CBF) as well as information on how the ischaemic tissue metabolic changes develop. It follows that, as therapeutic options for treating acute stroke evolve, neuroimaging strategies are assuming an increasingly important role in the initial evaluation and management of the acute ischaemic patient. In this regard, a wide range of therapeutic approaches have been investigated for either ameliorating the perfusion, or interfering with the pathobiochemical cascade leading to ischaemic neuronal damage, or improving endogenous neuroprotection pathways. The "time windows" required for these treatments to be effective varies being rather short for reperfusion and longer for neuroprotection. Salvaging more penumbra would enhance recovery and thereby allow the most appropriate candidate for therapeutic trials to be selected.

  3. Application of Whole-brain Perfusion CT with 320-detector Row CT System in Staging of Cerebral Ischemic Penumbra%320排动态容积CT全脑灌注成像在脑梗死缺血半暗带分期中的应用

    Institute of Scientific and Technical Information of China (English)

    向永华; 王波; 金科; 杨伟; 汪春红

    2012-01-01

    Purpose To investigate the feasibility of staging cerebral ischemic penumbra using 320-detector row CT whole-brain perfusion imaging. Materials and Methods The values of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were measured in infarct core area, ischemic penumbra, and mirror area in 18 cases with ischemic penumbra. The staging of the ischemic penumbra was made according to the criteria of pre-infarction period staging. Results In 18 cases with ischemic penumbra, MTT and TTP were delayed; CBF was decreased; CBV was slightly decreased, normal or slightly increased. Compared with infarct core area, CBV and CBF were increased, MTT was delayed and TTP was shortened in ischemic penumbra (P 0.05). In 18 cases, three cases were in stage I 2, nine cases in stage Ⅱ1, six cases in stage Ⅱ2. Conclusion Application of whole-brain perfusion CT with 320-detector row CT system can identify the area of cerebral lesions and the existence of ischemic penumbra.%目的 应用320排动态容积CT全脑灌注成像探讨脑梗死缺血半暗带分期的可行性.资料与方法 测量18例存在缺血半暗带脑梗死患者的梗死核心区、缺血半暗带区及其镜像对侧脑血容量(CBV)、脑血流量(CBF)、平均通过时间(MTT)及达峰时间(TTP),按脑梗死前期分期标准对缺血半暗带进行分期.结果 18例缺血半暗带区表现为MTT、TTP延长,CBF降低,CBV轻度升高、正常或轻度降低.与梗死核心区比较,缺血半暗带区CBV、CBF升高,MTT延长,TTP缩短(P<0.05);与健侧对应区比较,CBF降低,MTT及TTP延长(P<0.05),而CBV无显著差异(P>0.05).缺血半暗带分期:Ⅰ2期3例,Ⅱ1期9例,Ⅱ2期6例.结论 应用320排动态容积CT全脑灌注成像可明确脑梗死患者的病变部位、范围以及有无缺血半暗带存在,并可对缺血半暗带进行分期.

  4. Docosahexaenoic acid signaling modulates cell survival in experimental ischemic stroke penumbra and initiates long-term repair in young and aged rats.

    Directory of Open Access Journals (Sweden)

    Tiffany N Eady

    Full Text Available BACKGROUND: Docosahexaenoic acid, a major omega-3 essential fatty acid family member, improves behavioral deficit and reduces infarct volume and edema after experimental focal cerebral ischemia. We hypothesize that DHA elicits neuroprotection by inducing AKT/p70S6K phosphorylation, which in turn leads to cell survival and protects against ischemic stroke in young and aged rats. METHODS AND RESULTS: Rats underwent 2 h of middle cerebral artery occlusion (MCAo. DHA, neuroprotectin D1 (NPD1 or vehicle (saline was administered 3 h after onset of stroke. Neurological function was evaluated on days 1, 2, 3, and 7. DHA treatment improved functional recovery and reduced cortical, subcortical and total infarct volumes 7 days after stroke. DHA also reduced microglia infiltration and increased the number of astrocytes and neurons when compared to vehicle on days 1 and 7. Increases in p473 AKT and p308 AKT phosphorylation/activation were observed in animals treated with DHA 4 h after MCAo. Activation of other members of the AKT signaling pathway were also observed in DHA treated animals including increases in pS6 at 4 h and pGSK at 24 h. DHA or NPD1 remarkably reduced total and cortical infarct in aged rats. Moreover, we show that in young and aged rats DHA treatment after MCAo potentiates NPD1 biosynthesis. The phosphorylation of p308 AKT or pGSK was not different between groups in aged rats. However, pS6 expression was increased with DHA or NPD1 treatment when compared to vehicle. CONCLUSIONS: We suggest that DHA induces cell survival, modulates the neuroinflammatory response and triggers long term restoration of synaptic circuits. Both DHA and NPD1 elicited remarkable protection in aged animals. Accordingly, activation of DHA signaling might provide benefits in the management of ischemic stroke both acutely as well as long term to limit ensuing disabilities.

  5. Factors predicting poor prognosis in ischemic colitis

    Institute of Scientific and Technical Information of China (English)

    Ramón A(n)ón; Marta Maia Boscá; Vicente Sanchiz; Joan Tosca; Pedro Almela; Cirilo Amorós; Adolfo Benages

    2006-01-01

    AIM: To determine the clinical, analytical and endoscopic factors related to ischemic colitis (IC) severity. METHODS: A total of 85 patients were enrolled in a retrospective study from January 1996 to May 2004.There were 53 females and 32 males (age 74.6 ± 9.4 years, range 45-89 years). The patients were diagnosed as IC. The following variables were analyzed including age, sex, period of time from the appearance of symptoms to admission, medical history, medication, stool frequency, clinical symptoms and signs, blood tests (hemogram and basic biochemical profile), and endoscopic findings. Patients were divided in mild IC group and severe IC group (surgery and/or death). Qualitative variables were analyzed using chi-square test and parametric data were analyzed using Student's t test (P < 0.05).RESULTS: The mild IC group was consisted of 69 patients (42 females and 27 males, average age 74.7 ±12.4 years). The severe IC group was composed of 16 patients (11 females and 5 males, average age of 73.8 ± 12.4 years). One patient died because of failure of medical treatment (no surgery), 15 patients underwent surgery (6 after endoscopic diagnosis and 9 after peroperatory diagnosis). Eight of 85 patients (9.6%) died and the others were followed up as out-patients for 9.6 ± 3.5 mo. Demographic data, medical history, medication and stool frequency were similar in both groups (P >0.05). Seriously ill patients had less hematochezia than slightly ill patients (37.5% vs 86.9%, P = 0.000). More tachycardia (45.4% vs 10.1%, P = 0.011) and a higher prevalence of peritonism signs (75% vs 5.7%, P = 0.000) were observed in the severe IC group while the presence and intensity of abdominal pain were similar between two groups. Two patients with severe IC had shock when admitted. Regarding analytical data, more seriously ill patients were found to have anemia and hyponatremia than the mildly ill patients (37.5% vs 10.1%, P = 0.014 and 46.6% vs 14.9%, P = 0.012, respectively

  6. Computed tomography workup of patients suspected of acute ischemic stroke: perfusion computed tomography adds value compared with clinical evaluation, noncontrast computed tomography, and computed tomography angiogram in terms of predicting outcome.

    Science.gov (United States)

    Zhu, Guangming; Michel, Patrik; Aghaebrahim, Amin; Patrie, James T; Xin, Wenjun; Eskandari, Ashraf; Zhang, Weiwei; Wintermark, Max

    2013-04-01

    To determine whether perfusion computed tomography (PCT) adds value to noncontrast head CT (NCT), CT angiogram (CTA), and clinical assessment in patients suspected of acute ischemic stroke. We retrospectively reviewed 165 patients with acute ischemic stroke. PCT was used to calculate the volumes of infarct core and ischemic penumbra on admission. Other imaging data included Alberta Score Program Early CT Score, site of occlusion, and collateral flow. Clinical data included age, time, National Institutes of Health Stroke Scale at baseline, treatment type, and modified Rankin score (mRS) at 90 days. Recanalization status was assessed on follow-up imaging. In a first multivariate regression analysis, we assessed whether volumes of PCT penumbra and infarct core could be predicted from clinical variables, NCT, or CTA, or whether they represented independent information. In a second multivariate regression analysis, we used mRS at 90 days as outcome and determined which variables predicted it best. Of 165 patients identified, 76 had a mRS score of 0 to 2 at 90 days, 89 had a mRS score >2. PCT infarct could be predicted by clinical data, NCT, CTA, and combinations of this data (Pstroke CT workup, including NCT and CTA.

  7. Improving prediction of ischemic cardiovascular disease in the general population using apolipoprotein B

    DEFF Research Database (Denmark)

    Benn, Marianne; Nordestgaard, Børge G; Jensen, Gorm Boje

    2007-01-01

    Apolipoprotein B (apoB) levels predict fatal myocardial infarction. Whether apoB also predicts nonfatal ischemic cardiovascular events is unclear. We tested the following hypotheses: apoB predicts ischemic cardiovascular events, and apoB is a better predictor of ischemic cardiovascular events tha...

  8. Imaging-based management of acute ischemic stroke patients: Current neuroradiological perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Na, Dong Gyu [Dept. of Radiology, Neuroradiology, Head and Neck Radiology, Thyroid Radiology Human Medical Imaging and Intervention Center, Seoul (Korea, Republic of); Sohn, Chul Ho [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Eung Yeop [Dept. of Radiology, Gachon University Gil Medical Center, Incheon (Korea, Republic of)

    2015-04-15

    Advances in imaging-based management of acute ischemic stroke now provide crucial information such as infarct core, ischemic penumbra/degree of collaterals, vessel occlusion, and thrombus that helps in the selection of the best candidates for reperfusion therapy. It also predicts thrombolytic efficacy and benefit or potential hazards from therapy. Thus, radiologists should be familiar with various imaging studies for patients with acute ischemic stroke and the applicability to clinical trials. This helps radiologists to obtain optimal rapid imaging as well as its accurate interpretation. This review is focused on imaging studies for acute ischemic stroke, including their roles in recent clinical trials and some guidelines to optimal interpretation.

  9. Improving prediction of ischemic cardiovascular disease in the general population using apolipoprotein B

    DEFF Research Database (Denmark)

    Benn, M; Nordestgaard, B; Jensen, Gorm Boje

    2007-01-01

    than low-density lipoprotein cholesterol in the prediction of ischemic heart disease, myocardial infarction, any ischemic cardiovascular event, and any nonfatal ischemic cardiovascular event in both genders (P=0.03 to years with systolic blood pressure >160 mm...... Hg, apoB contributed 11% in women and 15% in men to the increase in absolute 10-year risk from the lower to the upper apoB tertile. Conclusion- ApoB predicts ischemic cardiovascular events in both genders, and is better than low-density lipoprotein cholesterol in this respect. We suggest......Background- Apolipoprotein B (apoB) levels predict fatal myocardial infarction. Whether apoB also predicts nonfatal ischemic cardiovascular events is unclear. We tested the following hypotheses: apoB predicts ischemic cardiovascular events, and apoB is a better predictor of ischemic cardiovascular...

  10. The Growth of a Primitive Penumbra

    Science.gov (United States)

    Sreejith, P.; Tritschler, A.; Sankarasubramanian, K.

    We report on the penumbral formation in active region NOAA 10837. The penumbra observed on continuum intensity images grew from a quiet-Sun area to a primitive penumbra and then to a fully developed penumbra over about 5 h. The growth indicates nonlinear development with time.

  11. Low ankle-brachial index predicts cardiovascular risk after acute ischemic stroke or transient ischemic attack.

    Science.gov (United States)

    Busch, Markus A; Lutz, Katrin; Röhl, Jens-Eric; Neuner, Bruno; Masuhr, Florian

    2009-12-01

    A low ankle-brachial blood pressure index (ABI) is an established risk marker for cardiovascular disease and mortality in the general population, but little is known about its prognostic value in individuals with acute ischemic stroke or transient ischemic attack (TIA). An inception cohort of 204 patients with acute ischemic stroke or TIA was followed up for a mean of 2.3 years. At baseline, patients underwent ABI measurement and were assessed for risk factors, cardiovascular comorbidities, and cervical or intracranial artery stenosis. The association between low ABI (stroke, myocardial infarction, or death was examined by Kaplan-Meier and Cox regression analyses. A low ABI was found in 63 patients (31%) and was associated with older age, current smoking, hypertension, peripheral arterial disease, and cervical or intracranial stenosis. During a total of 453.0 person-years of follow-up, 37 patients experienced outcome events (8.2% per person-year), with a higher outcome rate per person-year in patients with low ABI (12.8% vs 6.3%, P=0.03). In survival analysis adjusted for age and stroke etiology, patients with a low ABI had a 2 times higher risk of stroke, myocardial infarction, or death than those with a normal ABI (hazard ratio=2.2; 95% CI, 1.1 to 4.5). Additional adjustment for risk factors and cardiovascular comorbidities did not attenuate the association. A low ABI independently predicted subsequent cardiovascular risk and mortality in patients with acute stroke or TIA. ABI measurement may help to identify high-risk patients for targeted secondary stroke prevention.

  12. Does computed tomography permeability predict hemorrhagic transformation after ischemic stroke?

    Institute of Scientific and Technical Information of China (English)

    Peggy Yen; Allison Cobb; Jai Jai Shiva Shankar

    2016-01-01

    AIM: To use perfusion-derived permeability-surface area product maps to predict hemorrhagic transformation following thrombolytic treatment for acute ischemic stroke.METHODS: We retrospectively analyzed our prospectively kept acute stroke database over five consecutive months for patients with symptoms of acute ischemic stroke(AIS) who had computed tomography(CT) perfusion(CTP) done at arrival. Patients included in the analyses also had to have a follow-up CT. The permeability-surface area product maps(PS) was calculated for the side of the ischemia and/or infarction and for the contralateral unaffected side at the same level. The cerebral blood flow map was used to delineate the ischemic territory. Next, a region of interest was drawn at the centre of this territory on the PS parametric map. Finally, a mirror region of interest was created on the contralateral side at the same level. The relative permeability-surface area product maps(r PS) provided an internal control and was calculated as the ratio of the PS on the side of the AIS to the PS on the contralateral side. A student t-test was performed after log conversion of r PS between patients with and without hemorrhagic transformation. Log conversion was used to convert the data into normal distribution to use t-test. For the group of patients who experienced intracranial bleed, a student t-test was performed between those with only petechial hemorrhage and those with more severe parenchymal hematoma with subarachnoid haemorrhage.RESULTS: Of 84 patients with AIS and CTP at admission, only 42 patients had a follow-up CT. The r PSderived using the normal side as the internal control was significantly higher(P = 0.003) for the 15 cases of hemorrhagic transformation(1.71 + 1.64) compared to 27 cases that did not have any(1.07 + 1.30). Patients with values above the overall mean r PS of 1.3 had an increased likelihood of subsequent hemorrhagic transformation. The sensitivity of using this score to predict

  13. Penumbra

    DEFF Research Database (Denmark)

    Bengtsen, Søren Smedegaard; Wisker, Gina; Robinson, Gill

    2016-01-01

    the ‘darkside’, verging on plagiarism, substitution of effort, bad practice. We identify those in support as resembling a ‘penumbra’ a light around the main activity, and adopted an analogy of dramatic production roles to explore work of the various cast and production team supporting PhD students’ work....

  14. Penumbra

    DEFF Research Database (Denmark)

    Bengtsen, Søren Smedegaard; Wisker, Gina; Robinson, Gill

    2016-01-01

    the ‘darkside’, verging on plagiarism, substitution of effort, bad practice. We identify those in support as resembling a ‘penumbra’ a light around the main activity, and adopted an analogy of dramatic production roles to explore work of the various cast and production team supporting PhD students’ work....... consider formal and informal learning communities supporting students in their research journeys, and roles played by families, friends and others, sometimes offering encouragement and sometimes an added stress. However, little has yet been explored, exposed and shared concerning the often unofficial...

  15. Value of Whole Brain Computed Tomography Perfusion for Predicting Outcome after TIA or Minor Ischemic Stroke

    NARCIS (Netherlands)

    Van Den Wijngaard, Ido R.; Algra, Ale; Lycklama À Nijeholt, Geert J.; Boiten, Jelis; Wermer, Marieke J H; Van Walderveen, Marianne A A

    2015-01-01

    Introduction About 15% of patients with transient ischemic attack (TIA) or minor ischemic stroke have functional impairment after 3 months. We studied the role of whole brain computed tomography perfusion (WB-CTP) in the emergency diagnosis of TIA or minor stroke in predicting disability at 3 months

  16. Medical image analysis methods in MR/CT-imaged acute-subacute ischemic stroke lesion: Segmentation, prediction and insights into dynamic evolution simulation models. A critical appraisal☆

    Science.gov (United States)

    Rekik, Islem; Allassonnière, Stéphanie; Carpenter, Trevor K.; Wardlaw, Joanna M.

    2012-01-01

    Over the last 15 years, basic thresholding techniques in combination with standard statistical correlation-based data analysis tools have been widely used to investigate different aspects of evolution of acute or subacute to late stage ischemic stroke in both human and animal data. Yet, a wave of biology-dependent and imaging-dependent issues is still untackled pointing towards the key question: “how does an ischemic stroke evolve?” Paving the way for potential answers to this question, both magnetic resonance (MRI) and CT (computed tomography) images have been used to visualize the lesion extent, either with or without spatial distinction between dead and salvageable tissue. Combining diffusion and perfusion imaging modalities may provide the possibility of predicting further tissue recovery or eventual necrosis. Going beyond these basic thresholding techniques, in this critical appraisal, we explore different semi-automatic or fully automatic 2D/3D medical image analysis methods and mathematical models applied to human, animal (rats/rodents) and/or synthetic ischemic stroke to tackle one of the following three problems: (1) segmentation of infarcted and/or salvageable (also called penumbral) tissue, (2) prediction of final ischemic tissue fate (death or recovery) and (3) dynamic simulation of the lesion core and/or penumbra evolution. To highlight the key features in the reviewed segmentation and prediction methods, we propose a common categorization pattern. We also emphasize some key aspects of the methods such as the imaging modalities required to build and test the presented approach, the number of patients/animals or synthetic samples, the use of external user interaction and the methods of assessment (clinical or imaging-based). Furthermore, we investigate how any key difficulties, posed by the evolution of stroke such as swelling or reperfusion, were detected (or not) by each method. In the absence of any imaging-based macroscopic dynamic model

  17. WIN55,212-2 protects oligodendrocyte precursor cells in stroke penumbra following permanent focal cerebral ischemia in rats

    Institute of Scientific and Technical Information of China (English)

    Jing SUN; Yin-quan FANG; Hong REN; Tao CHEN; Jing-jing GUO; Jun YAN; Shu SONG; Lu-yong ZHANG; Hong LIAO

    2013-01-01

    Aim:To explore whether the synthetic cannabinoid receptor agonist WIN55,212-2 could protect oligodendrocyte precursor cells (OPCs)in stroke penumbra,thereby providing neuroprotection following permanent focal cerebral ischemia in rats.Methods:Adult male SD rats were subjected to permanent middle cerebral artery occlusion (p-MCAO).The animals were administered WIN55,212-2 at 2 h,and sacrificed at 24 h after the ischemic insult.The infarct volumes and brain swelling were assessed.The expression of cannabinoid receptor type 1 (CB1) in the stroke penumbra was examined using Western blot assay.The pathological changes and proliferation of neural glial antigen 2-positive OPCs (NG2+ cells) in the stroke penumbra were studied using immunohistochemistry staining.Results:p-MCAO significantly increased the expression of CB1 within the stroke penumbra with the highest level appearing at 2 h following the ischemic insult.Administration of WIN55,212-2 (9 mg/kg,iv) significantly attenuated the brain swelling,and reduced the infarct volume as well as the number of tau-immunoreactive NG2+ cells (tau-1+/NG2+ cells) in the stroke penumbra.Moreover,WIN55,212-2 significantly promoted the proliferation of NG2+ cells in the stroke penumbra and in the ipsilateral subventricular zone at 24 h following the ischemic insult.Administration of the selective CB1 antagonist rimonabant (1 mg/kg,iv) partially blocked the effects caused by WIN55,212-2.Conclusion:Tau-1 is expressed in NG2+ cells following permanent focal cerebral ischemic injury.Treatment with WIN55,212-2 reduces the number of tau-1+/NG2+ cells and promotes NG2+ cell proliferation in the stroke penumbra,which are mediated partially via CB1 and may contribute to its neuroprotective effects.

  18. White Matter Hyperintensities Improve Ischemic Stroke Recurrence Prediction

    DEFF Research Database (Denmark)

    Andersen, Søren Due; Larsen, Torben Bjerregaard; Gorst-Rasmussen, Anders;

    2017-01-01

    -based, observational cohort study, we included 832 patients (mean age 59.6 (SD 13.9); 42.0% females) with incident ischemic stroke and no AF. We assessed the severity of white matter hyperintensities using MRI. Hazard ratios stratified by the white matter hyperintensities score and adjusted for the components......BACKGROUND: Nearly one in 5 patients with ischemic stroke will invariably experience a second stroke within 5 years. Stroke risk stratification schemes based solely on clinical variables perform only modestly in non-atrial fibrillation (AF) patients and improvement of these schemes will enhance...... their clinical utility. Cerebral white matter hyperintensities are associated with an increased risk of incident ischemic stroke in the general population, whereas their association with the risk of ischemic stroke recurrence is more ambiguous. In a non-AF stroke cohort, we investigated the association between...

  19. Noncontrast Computed Tomography versus Computed Tomography Angiography Source Images for Predicting Final Infarct Size in Anterior Circulation Acute Ischemic Stroke: a Prospective Cohort Study.

    Science.gov (United States)

    Mukherjee, Amritendu; Muthusami, Prakash; Mohimen, Aneesh; K, Srinivasan; B, Babunath; Pn, Sylaja; Kesavadas, Chandrasekharan

    2017-02-01

    There has been a recent debate regarding the superiority of computed tomography angiography source images (CTASIs) over noncontrast computed tomography (NCCT) to predict the final infarct size in acute ischemic stroke (AIS). We hypothesized that the parenchymal abnormality on CTASI in faster scanners would overestimate ischemic core. This prospective study assessed the correlation of Alberta Stroke Program Early CT Score (ASPECTS) on NCCT, CTASI, and computed tomography perfusion (CTP) with final infarct size in patients within 8 hours of AIS. Follow-up with NCCT or diffusion-weighted magnetic resonance imaging (MRI) was performed at 24 hours. Correlations of NCCT and CTASI with final infarct size and with CTP parameters were assessed. Subgroup analysis was performed in patients who underwent intravenous thrombolysis or mechanical thrombectomy. Inter-rater reliability was tested using Spearman's rank correlation. A P value less than .05 was considered statistically significant. A total of 105 patients were included in the final analysis. NCCT had a stronger correlation with the final infarct size than did CTASI (Spearman's ρ = .85 versus .78, P = .13). We found an overestimation of the final infarct size by CTASI in 47.6% of the cases, whereas NCCT underestimated infarct size in 60% of the patients. NCCT correlated most strongly with CBV (ρ = .93), whereas CTASI correlated most strongly with CBF (ρ = .87). Subgroup analysis showed less correlation of CTASI with final infarct size in the group that received thrombolysis versus the group that did not (ρ = .70 versus .88, P = .01). In a 256-slice scanner, the CTASI parenchymal abnormality includes ischemic penumbra and thus overestimates final infarct size-this could result in inappropriate exclusion of patients from thrombolysis or thrombectomy. Copyright © 2017 National Stroke Association. All rights reserved.

  20. Characteristics of Misclassified CT Perfusion Ischemic Core in Patients with Acute Ischemic Stroke

    NARCIS (Netherlands)

    Geuskens, R.R.; Borst, J.; Lucas, M.; Boers, A.M.; Berkhemer, O.A.; Roos, Y.B.; Walderveen, M.A. van; Jenniskens, S.F.M.; Zwam, W.H. van; Dippel, D.W.; Majoie, C.B.; Marquering, H.A.

    2015-01-01

    BACKGROUND: CT perfusion (CTP) is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to

  1. Research progress in traumatic brain penumbra

    Institute of Scientific and Technical Information of China (English)

    Wang Kai; Liu Baiyun; Ma Jun

    2014-01-01

    Objective Following traumatic brain injury (TBI),brain tissue that surrounding the regional primary lesion is known as traumatic penumbra; this region may undergo secondary injury and is considered to have the potential to recover.This review aimed to reveal the existence and significance of traumatic penumbra by analyzing all relevant studies concerning basic pathologic changes and brain imaging after TBI.Data sources We collected all relevant studies about TBI and traumatic penumbra in Medline (1995 to June 2013) and ISI (1997 to March 2013),evaluated their quality and relevance,then extracted and synthesized the information.Study selection We included all relevant studies concerning TBI and traumatic penumbra (there was no limitation of research design and article language) and excluded the duplicated articles.Results The crucial pathological changes after TBI include cerebral blood flow change,cerebral edema,blood-brain barrier damage,cell apoptosis and necrosis.Besides,traditional imaging method cannot characterize the consequences of CBF reduction at an early stage and provides limited insights into the underlying pathophysiology.While advanced imaging technique,such as diffusion tensor imaging (DTI) and positron emission tomography (PET),may provide better characterization of such pathophysiology.Conclusions The future of traumatic brain lesions depends to a large extent on the evolution of the penumbra.Therefore,understanding the formation and pathophysiologic process of the traumatic penumbra and its imaging research progress is of great significant for early clinical determination and timely brain rescue.

  2. Effect of baseline magnetic resonance imaging (MRI) apparent diffusion coefficient lesion volume on functional outcome in ischemic stroke.

    Science.gov (United States)

    Ma, Li; Gao, Pei-yi; Hu, Qing-mao; Lin, Yan; Jing, Li-na; Xue, Jing; Chen, Zhi-jun; Wang, Yong-jun; Liu, Mei-li; Cai, Ye-feng

    2011-06-01

    We explored the relationship between predicted infarct core, predicted ischemic penumbras and predicted final infarct volumes obtained though apparent diffusion coefficient (ADC)-based method, as well as other clinical variables, and functional outcome. Patients with acute cerebral ischemic stroke were retrospectively recruited. The National Institutes of Health Stroke Scale score was evaluated at baseline and the modified Rankin Scale (mRS) at day 90. Favorable outcome was defined as an mRS score of 0 to 2, and unfavorable outcome as 3 to 6. Multimodal stroke magnetic resonance imaging was carried out at presentation. The volumes of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) were measured using the regions of interest (ROI) method. The volumes of predicted infarct core, predicted ischemic penumbra and predicted final infarct were obtained by an automated image analysis system based on baseline ADC maps. The association between baseline magnetic resonance imaging volumes, baseline clinical variables, and functional outcome was statistically analyzed. The study included 30 males and 20 females (mean±SD age, 56±10 years). Baseline DWI, PWI and PWI-DWI mismatch volumes were not correlated with day-90 mRS (P>0.05). Predicted infarct core, predicted ischemic penumbra and predicted final infarct through ADC-based method were all correlated with day-90 mRS (PStroke Scale and recanalization also demonstrated a trend toward a favorable outcome. Receiver operating characteristic analysis showed that the area under the curve of predicted final infarct volume and recanalization were higher with statistical significance (PStroke Scale and recanalization may have effect on functional outcome in acute ischemic stroke.

  3. Transient ischemic attacks - Definition, risk prediction and urgent management

    Directory of Open Access Journals (Sweden)

    Sylaja P

    2009-01-01

    Full Text Available Recent evidence suggests that the risk of stroke in first few months after transient ischemic attack is higher than that was previously realized. There are clinical and imaging predictors which help in risk stratifying the patients to identify the high risk group who need immediate hospitalization and urgent evaluation. Recent advances in neuroimaging have revolutionized the evaluation of these patients. Further research is required in the deciding on the optimal treatment of these patients in the acute phase.

  4. The use of blood biomarkers to predict poor outcome after acute transient ischemic attack or ischemic stroke.

    Science.gov (United States)

    Whiteley, William; Wardlaw, Joanna; Dennis, Martin; Lowe, Gordon; Rumley, Ann; Sattar, Naveed; Welsh, Paul; Green, Alison; Andrews, Mary; Sandercock, Peter

    2012-01-01

    The prediction of death or disability ("poor outcome") after stroke by validated clinical models might be improved by the addition of blood biomarker measurements. We investigated whether such measurements improved the classification of patients into 4 categories of predicted risk of poor outcome: very high, intermediate high, intermediate low, and very low. We prospectively recruited symptomatic patients within 24 hours of ischemic cerebrovascular events. We measured clinical prognostic variables in each patient. We drew blood soon after admission and measured markers of inflammation, thrombosis, cardiac strain, and cerebral damage. We assessed poor outcome at 3 months with the modified Rankin Scale and recovery of symptoms at 24 hours. We measured the association between blood marker levels and poor outcome after adjustment for stroke severity and age with multivariate logistic regression. Where these associations were statistically significant, we calculated the net reclassification index. We recruited 270 patients with acute ischemic cerebrovascular events. At 3 months, 112 patients had a poor outcome. After adjustment for stroke severity and age, only interleukin-6 and N-terminal pro-brain natriuretic peptide were significantly associated with poor outcome. The addition of either interleukin-6 or N-terminal pro-brain natriuretic peptide to National Institutes of Health Stroke Scale and age did not improve the prediction of a poor outcome. Neither interleukin-6 nor N-terminal pro-brain natriuretic peptide had sufficient predictive power to be of clinical use to predict poor outcome after stroke. The search for better markers to improve the classification of patients across clinically relevant boundaries of predicted probabilities of outcome events needs to continue.

  5. 猴大脑中动脉闭塞模型脑缺血半暗带的面积演变%Evolution of ischemic penumbra area in monkey middle cerebral artery occlusion model

    Institute of Scientific and Technical Information of China (English)

    孙志华; 张雪君; 冯前进; 张云亭

    2009-01-01

    Objective To investigate the evolution of monkey brain isehemic penumbra(IP)area.Methods Seyen monkeys were used to make middle cerebral artery occlusion(MCAO)model by interventional methods.CT perfnsion imaging,MR diffusion weighted-imaging (DWI),perfusion weighted imaging(PWI)and T2W1 were performed at 1,5,10;15,20 and 24 h after MCAO respectively.Four regions of interest of infarct lesion were measured.Point 1 was at the infarct core.point 3 was at the infamt margin,and point 2 was at the midpoint between point 1 and 3.Point 4 demonstrated normal signal intensity adjacent to high signal intensity.Parameters measured included cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), apparent diffusion coefficient (ADC) and negative enhancement integral (NEI).The relative ratios between infarct lesions and the corresponding contralateral normal brain were calculated(rCBF, rCBV, rMTY, rADC and rNEI).The IP areas were calculated by two methods: IP thresholds combined with self-made computer software, and PWI( MrlT)-DWI mismatch.ANOVA and ROC analysis were used. Results Five of 7 monkey MCAO models were made successfuUy. There were signitlcanfly difference of rCBF and rNEI within 20 h, of rCBV within 15 h, of rADC within 10 h, of rMTT at24 h (P<0.05).ROI 1,2 and 3 values as following: rCBF: 1 h(0.160 ±0.034, 0.310 ±0.037,0.540±0.107), 5 h(0.098±0.029, 0.157 ± 0.052, 0.427 ±0.116), 10 h(0.072 ±0.023, 0.097 ±0.028, 0.209 ± 0.070), 15 h(0.054 ± 0.017, 0.069 ± 0.015, 0.166 ± 0.049), 20 h(0.038 ± 0.011,0.026± 0.007, 0.092±0.013); rNEI: 1 h(0.219 ± 0.085, 0.303 ± 0.099, 0.463 ± 0.132), 5 h (0.143±0.057, 0.195± 0.055, 0.348±0.127), 10 h(0.127 ± 0.029, 0.171 ± 0.058, 0.259 ±0.079), 15 h(0.128 ±0.024, 0.164 ±0.031, 0.217 ±0.030), 20 h(0.075±0.019, 0.147±0.058,0.129 ±0.045) ; rCBV: 1 h(0.594 ± 0.199, 0.804 ± 0.099, 1.021 ±0.169), 5 h(0.457±0.103,0.462±0.145, 0.815±0.201), 10 h(0.222 ±0.046, 0.249±0.065, 0.529 ±0

  6. Prediction factors of recurrent ischemic events in one year after minor stroke.

    Directory of Open Access Journals (Sweden)

    Changqing Zhang

    Full Text Available BACKGROUND: The risk of a subsequent stroke following a minor stroke is high. However, there are no effective rating scales to predict recurrent stroke following a minor one. Therefore, we assessed the risk factors associated with recurrent ischemic stroke or transient ischemic attack (TIA within one year of minor stroke onset in order to identify possible risk factors. METHODS: Eight hundred and sixty-three non-cardioembolic ischemic stroke patients in the Chinese IntraCranial AtheroSclerosis Study that presented with minor stroke, defined as an admission National Institutes of Health stroke scale (NIHSS score of ≤3, were consecutively enrolled in our study. Clinical information and imaging features upon admission, and any recurrent ischemic stroke or TIA within one year was recorded. Cox regression was used to identify risk factors associated with recurrent ischemic stroke or TIA within the year following stroke onset. RESULTS: A total of 50 patients (6.1% experienced recurrent ischemic stroke or TIA within one year of minor stroke onset. Multivariate Cox regression model identified lower admission NIHSS score (HR, 1.75; 95% CI, 1.32 to 2.33; P<0.0001, history of coronary heart disease (HR, 2.62; 95% CI, 1.17 to 5.86; P = 0.02, severe stenosis or occlusion of large cerebral artery (HR, 4.68; 95% CI, 1.87 to 11.7; P = 0.001, and multiple acute cerebral infarcts (HR, 2.61; 95% CI, 1.01 to 6.80; P = 0.05 as independent risk factors for recurrent ischemic stroke or TIA within one year. CONCLUSIONS: Some minor stroke patients are at higher risk for recurrent ischemic stroke or TIA. Urgent and intensified therapy may be reasonable in these patients.

  7. 胞二磷胆碱结合康复训练对脑缺血大鼠半暗带区存活素表达的影响%The effect of drugs in combination with rehabilitative training on the expression of survivin in the ischemic penumbra after focal cerebral ischemia in rats

    Institute of Scientific and Technical Information of China (English)

    毕然然; 孙强三; 孙丽

    2013-01-01

    Objective To investigate the effect of drugs in combination with rehabilitative training on motor function and the expression of survivin in the ischemic penumbra after focal cerebral ischemia.Methods One hundred and twenty male,adult,Sprague-Dawley rats were subjected to left middle cerebral artery occlusion (MCAO)by suturing.Ninety-six of them were then randomly divided into a control group,a drug group,a rehabilitative trainiug group,and a drugs in combination with rehabilitative training group,with 24 in each.For three days the rats in the control group received no treatment,while those in the drug group received 500 mg/kg of citicoline daily,those in the rehabilitative training group received motor training including balancing,grasping,rotating and walking exercises,aud those in the drug and rehabilitative training group received both citicoline and the motor training.Behavioral tests were administered to all groups,and immunohistochemistry was used to detect the expression of survivin in the ischemic penumbra.Results Average behavior scores in the drug group and the control group were not significantly different at day 7,14 or 21 after the MCAO.Average behavior scores in the rehabilitative training and drug in combination with rehabilitative training groups were significantly superior to those of the control and drug groups at day 14 and 21.At those time points the average scores in the drug in combination with rehabilitative training group were also significantly better than those of the rehabilitation training group.Compared with control group,at the 7th,14th and 21st day after MCAO,expression of survivin in the other three groups had increased significantly.Expression of survivin in the group where drug treatment was combined with rehabilitative training was significantly greater than in the drug and rehabilitative training groups.Conclusions Citicoline in combination with rehabilitative training can improve the recovery of motor function in rats

  8. Value of Computed Tomographic Perfusion-Based Patient Selection for Intra-Arterial Acute Ischemic Stroke Treatment.

    Science.gov (United States)

    Borst, Jordi; Berkhemer, Olvert A; Roos, Yvo B W E M; van Bavel, Ed; van Zwam, Wim H; van Oostenbrugge, Robert J; van Walderveen, Marianne A A; Lingsma, Hester F; van der Lugt, Aad; Dippel, Diederik W J; Yoo, Albert J; Marquering, Henk A; Majoie, Charles B L M

    2015-12-01

    The utility of computed tomographic perfusion (CTP)-based patient selection for intra-arterial treatment of acute ischemic stroke has not been proven in randomized trials and requires further study in a cohort that was not selected based on CTP. Our objective was to study the relationship between CTP-derived parameters and outcome and treatment effect in patients with acute ischemic stroke because of a proximal intracranial arterial occlusion. We included 175 patients who underwent CTP in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN). Association of CTP-derived parameters (ischemic-core volume, penumbra volume, and percentage ischemic core) with outcome was estimated with multivariable ordinal logistic regression as an adjusted odds ratio for a shift in the direction of a better outcome on the modified Rankin Scale. Interaction between CTP-derived parameters and treatment effect was determined using multivariable ordinal logistic regression. Interaction with treatment effect was also tested for mismatch (core 1.2; penumbra core >10 mL). The adjusted odds ratio for improved functional outcome for ischemic core, percentage ischemic core, and penumbra were 0.79 per 10 mL (95% confidence interval: 0.71-0.89; P<0.001), 0.82 per 10% (95% confidence interval: 0.66-0.90; P=0.002), and 0.97 per 10 mL (96% confidence interval: 0.92-1.01; P=0.15), respectively. No significant interaction between any of the CTP-derived parameters and treatment effect was observed. We observed no significant interaction between mismatch and treatment effect. CTP seems useful for predicting functional outcome, but cannot reliably identify patients who will not benefit from intra-arterial therapy. © 2015 American Heart Association, Inc.

  9. Anomalous flows in a sunspot penumbra

    CERN Document Server

    Louis, Rohan E; Mathew, Shibu K; Venkatakrishnan, P

    2014-01-01

    High-resolution spectropolarimetric observations of active region NOAA 11271 were obtained with the spectro-polarimeter on board Hinode to analyze the properties of an anomalous flow in the photosphere in a sunspot penumbra. We detect a blue-shifted feature that appeared on the limb-side penumbra of a sunspot and that was present intermittently during the next two hours. It exhibited a maximum blue-shift of 1.6 km/s, an area of 5.2 arcsec^2, and an uninterrupted lifetime of 1 hr. The blue-shifted feature, when present, lies parallel to red-shifts. Both blue and red shifts flank a highly inclined/horizontal magnetic structure that is radially oriented in the penumbra. The low-cadence SP maps reveal changes in size, radial position in the penumbra and line-of-sight velocity of the blue-shifted feature, from one scan to the other. There was an increase of nearly 500 G in the field strength and a marginal reduction in the field inclination of about 10 deg with the onset of the blue-shifts. In the chromosphere, in...

  10. A Fully Automated Penumbra Segmentation Tool

    DEFF Research Database (Denmark)

    Nagenthiraja, Kartheeban; Ribe, Lars Riisgaard; Hougaard, Kristina Dupont

    2012-01-01

    salavageable tissue, quickly and accurately. We present a fully Automated Penumbra Segmentation (APS) algorithm using PWI and DWI images. We compare automatically generated PWI-DWI mismatch mask to mask outlined manually by experts, in 168 patients. Method: The algorithm initially identifies PWI lesions...

  11. Comparison of statistical and clinical predictions of functional outcome after ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Douglas D Thompson

    Full Text Available To determine whether the predictions of functional outcome after ischemic stroke made at the bedside using a doctor's clinical experience were more or less accurate than the predictions made by clinical prediction models (CPMs.A prospective cohort study of nine hundred and thirty one ischemic stroke patients recruited consecutively at the outpatient, inpatient and emergency departments of the Western General Hospital, Edinburgh between 2002 and 2005. Doctors made informal predictions of six month functional outcome on the Oxford Handicap Scale (OHS. Patients were followed up at six months with a validated postal questionnaire. For each patient we calculated the absolute predicted risk of death or dependence (OHS≥3 using five previously described CPMs. The specificity of a doctor's informal predictions of OHS≥3 at six months was good 0.96 (95% CI: 0.94 to 0.97 and similar to CPMs (range 0.94 to 0.96; however the sensitivity of both informal clinical predictions 0.44 (95% CI: 0.39 to 0.49 and clinical prediction models (range 0.38 to 0.45 was poor. The prediction of the level of disability after stroke was similar for informal clinical predictions (ordinal c-statistic 0.74 with 95% CI 0.72 to 0.76 and CPMs (range 0.69 to 0.75. No patient or clinician characteristic affected the accuracy of informal predictions, though predictions were more accurate in outpatients.CPMs are at least as good as informal clinical predictions in discriminating between good and bad functional outcome after ischemic stroke. The place of these models in clinical practice has yet to be determined.

  12. Multimodal MR examination in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Mezzapesa, D.M.; Petruzzellis, M.; Lucivero, V.; Prontera, M.; Tinelli, A.; Sancilio, M.; Carella, A.; Federico, F. [University of Bari, Department of Neurological and Psychiatric Sciences, Bari (Italy)

    2006-04-15

    In recent years, combined diffusion-weighted imaging (DWI) with perfusion imaging (PI) has become an important investigational tool in the acute phase of ischemic stroke, as it may differentiate reversible from irreversible brain tissue damage. We consecutively examined 20 subjects within 12 h of stroke onset using a multiparametric magnetic resonance (MR) examination consisting of DWI, mean transit time (MTT) as PI parameter, and MR angiography (MRA). T2-weighted and fluid-attenuated inversion recovery (FLAIR) on day 7 were also acquired in order to obtain final infarct volume. The following MR parameters were considered: volumetric measures of lesion growth and MTT abnormalities, quantification of regional apparent diffusion coefficient (ADC) and visual inspection of MRA findings. Our results showed: (1) an acute DWI lesion was not predictive of lesion growth and the DWI abnormality did not represent the irreversibly infarcted tissue; (2) ADC values in the ischemic penumbra could not predict tissue at risk; (3) the DWI-PI mismatch did not predict lesion growth, and the PI abnormality overestimated the amount of tissue at risk; and (4) patients with proximal middle cerebral artery occlusion had greater initial and final infarct volumes. This study did not demonstrate the prognostic value of a multimodal MR approach in early ischemic stroke; MRA alone provided predictive information about the volumetric evolution of the lesion. (orig.)

  13. The iScore predicts effectiveness of thrombolytic therapy for acute ischemic stroke.

    Science.gov (United States)

    Saposnik, Gustavo; Fang, Jiming; Kapral, Moira K; Tu, Jack V; Mamdani, Muhammad; Austin, Peter; Johnston, S Claiborne

    2012-05-01

    Tools to predict the clinical response after intravenous thrombolytic therapy (tPA) are scarce. The iScore is an existing validated tool to estimate outcomes after an acute ischemic stroke. The purpose of this study was to determine the ability of the iScore to predict clinical response and risk of hemorrhagic transformation after tPA. We applied the iScore (www.sorcan.ca/iscore) to patients presenting with an acute ischemic stroke at 11 stroke centers in Ontario, Canada, between 2003 and 2009 identified from the Registry of the Canadian Stroke Network. A cohort of patients with stroke treated at 154 centers in Ontario was used for external validation. We compared outcomes between patients receiving and not receiving tPA after adjusting for differences in baseline characteristics using propensity-score matching. Patients were stratified into 3 a priori defined groups according to stroke severity using the iScore. Among 12 686 patients with an acute ischemic stroke, 1696 (13.4%) received intravenous thrombolysis. Higher iScores were associated with poor outcomes in both the tPA and non-tPA groups (Pacute ischemic stroke. Patients with high iScores may not have a clinically meaningful benefit from intravenous tPA at the time of carrying a higher risk of hemorrhagic complications.

  14. Use of APACHE II and SAPS II to predict mortality for hemorrhagic and ischemic stroke patients.

    Science.gov (United States)

    Moon, Byeong Hoo; Park, Sang Kyu; Jang, Dong Kyu; Jang, Kyoung Sool; Kim, Jong Tae; Han, Yong Min

    2015-01-01

    We studied the applicability of the Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) in patients admitted to the intensive care unit (ICU) with acute stroke and compared the results with the Glasgow Coma Scale (GCS) and National Institutes of Health Stroke Scale (NIHSS). We also conducted a comparative study of accuracy for predicting hemorrhagic and ischemic stroke mortality. Between January 2011 and December 2012, ischemic or hemorrhagic stroke patients admitted to the ICU were included in the study. APACHE II and SAPS II-predicted mortalities were compared using a calibration curve, the Hosmer-Lemeshow goodness-of-fit test, and the receiver operating characteristic (ROC) curve, and the results were compared with the GCS and NIHSS. Overall 498 patients were included in this study. The observed mortality was 26.3%, whereas APACHE II and SAPS II-predicted mortalities were 35.12% and 35.34%, respectively. The mean GCS and NIHSS scores were 9.43 and 21.63, respectively. The calibration curve was close to the line of perfect prediction. The ROC curve showed a slightly better prediction of mortality for APACHE II in hemorrhagic stroke patients and SAPS II in ischemic stroke patients. The GCS and NIHSS were inferior in predicting mortality in both patient groups. Although both the APACHE II and SAPS II systems can be used to measure performance in the neurosurgical ICU setting, the accuracy of APACHE II in hemorrhagic stroke patients and SAPS II in ischemic stroke patients was superior.

  15. Early Dynamics of P-selectin and Interleukin 6 Predicts Outcomes in Ischemic Stroke

    DEFF Research Database (Denmark)

    Pusch, Gabriella; Debrabant, Birgit; Molnar, Tihamer;

    2015-01-01

    with acute ischemic stroke (6, 24, and 72 hours after onset); (2) compared with 44 patients with asymptomatic severe (≥70%) carotid stenosis and 66 patients with Parkinson disease; and (3) we applied multiple regression methods, relating biological biomarkers combined with demographic data and comorbidities......BACKGROUND: Thromboinflammatory molecules connect the prothrombotic state, endothelial dysfunction, and systemic/local inflammation in the acute phase of ischemic stroke. METHODS: We prospectively investigated (1) serial changes in the levels of thromboinflammatory biomarkers in 76 patients...... of death by 7%. CONCLUSIONS: In regression models, in which biological, demographic, and comorbid factors were combined, those biological biomarkers predicted poor outcome with high accuracy, which were characterized by an increasing concentration by 72 hours. Two particular biomarkers emerged to predict...

  16. The value of preoperative 3-dimensional over 2-dimensional valve analysis in predicting recurrent ischemic mitral regurgitation after mitral annuloplasty

    NARCIS (Netherlands)

    Wijdh-den Hamer, Inez J.; Bouma, Wobbe; Lai, Eric K.; Levack, Melissa M.; Shang, Eric K.; Pouch, Alison M.; Eperjesi, Thomas J.; Plappert, Theodore J.; Yushkevich, Paul A.; Hung, Judy; Mariani, Massimo A.; Khabbaz, Kamal R.; Gleason, Thomas G.; Mahmood, Feroze; Acker, Michael A.; Woo, Y. Joseph; Cheung, Albert T.; Gillespie, Matthew J.; Jackson, Benjamin M.; Gorman, Joseph H.; Gorman, Robert C.

    2016-01-01

    Objectives: Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months. Methods: Intraoperative

  17. The value of preoperative 3-dimensional over 2-dimensional valve analysis in predicting recurrent ischemic mitral regurgitation after mitral annuloplasty

    NARCIS (Netherlands)

    Wijdh-den Hamer, Inez J.; Bouma, Wobbe; Lai, Eric K.; Levack, Melissa M.; Shang, Eric K.; Pouch, Alison M.; Eperjesi, Thomas J.; Plappert, Theodore J.; Yushkevich, Paul A.; Hung, Judy; Mariani, Massimo A.; Khabbaz, Kamal R.; Gleason, Thomas G.; Mahmood, Feroze; Acker, Michael A.; Woo, Y. Joseph; Cheung, Albert T.; Gillespie, Matthew J.; Jackson, Benjamin M.; Gorman, Joseph H.; Gorman, Robert C.

    Objectives: Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months. Methods: Intraoperative

  18. WIN55,212-2 protects oligodendrocyte precursor cells in stroke penumbra following permanent focal cerebral ischemia in rats

    OpenAIRE

    SUN, JING; Fang, Yin-quan; Ren, Hong; Tao CHEN; Guo, Jing-Jing; Yan, Jun; SONG, SHU; Zhang, Lu-yong; Liao, Hong

    2012-01-01

    Aim: To explore whether the synthetic cannabinoid receptor agonist WIN55,212-2 could protect oligodendrocyte precursor cells (OPCs) in stroke penumbra, thereby providing neuroprotection following permanent focal cerebral ischemia in rats. Methods: Adult male SD rats were subjected to permanent middle cerebral artery occlusion (p-MCAO). The animals were administered WIN55,212-2 at 2 h, and sacrificed at 24 h after the ischemic insult. The infarct volumes and brain swelling were assessed. The e...

  19. Blood oxygenation level dependent effect of cerebral ischemic penumbra in monkey reversible middle cerebral artery occlusion model%猴可复性大脑中动脉闭塞模型脑缺血半暗带的血氧水平依赖效应

    Institute of Scientific and Technical Information of China (English)

    张敬; 陈英敏; 张云亭

    2010-01-01

    Objective To investigate the value of blood oxygenation level dependent (BOLD) MRI in detecting monkey cerebral ischemic penumbra (IP). Methods Six monkeys were used to make reversible middle cerebral artery occlusion (MCAO) model by an interventional microcatheter method. MR DWI, PWI mean transit time (MTT), T_2WI and quantitative T_2 map, T_2~* map were performed at MCAO (0 h) and 1,3,6,12,24,48 h after reperfusion. Reversible transverse relaxation rate (R_2') BOLD imaging was calculated using quantitative T_2 and T_2~* maps. Lesion volume percentage (lesion volume/bilateral hemispheres volume) were measured on 0 h DWI,48 h T_2WI and TTC staining. Ischemic area was subdivided into infracted core (high signal area on both 0 h DWI and 48 h T_2 WI), IP (high signal on 0 h DWI, iso on 48 h T_2 WI) and oligemia (0 h delayed MTT, iso signal on both 0 h DWI and 48 h T_2 WI). Relative R_2' (rR_2') was calculated to get ratio between the lesion and mirror area in contralateral healthyhemisphere. Paired t test and correlation analysis were used for comparison of lesion volume percentage. rR_2' values at each time point were compared by ANOVA. Results Reversible MCAO models were made successfully in 4 of 6 monkeys. Lesion volume porcentage on 48 h T_2 WI was reduced compared to that on Oh DWI [ (8.16±0.55)% vs (11.37±1.41)% ,t=6.472,P0.05], which showed significant positive correlation (r=0.98, P0.05),两者呈明显正相关(r=0.98,P<0.05).梗死核心、IP、低灌注区rR_2'在各时间点差异均有统计学意义,梗死核心低于IP,IP低于低灌注区(P<0.05),三者rR_2'值:0 h时分别为1.129±0.108、1.329±0.081、1.584±0.103(F=36.19,P<0.05).1 h分别为0.668±0.082、1.237±0.072、1.435±0.066(F=134.09,P<0.05).3 h分别为0.536±0.075、1.453±0.081、1.770±0.141(F=256.30,P<0.05).6 h分别为0.259±0.050、2.435±0.131、2.957±0.177(F=803.25,P<0.05).12 h分别为0.385±0.054、2.447±0.148、3.254±0.184(F=743.74,P<0.05).24 h分别为0.083±0.026、1

  20. 高频重复经颅磁刺激对脑梗死大鼠缺血半暗带超微结构及脑源性神经营养因子表达的影响%Effects of high-frequency repetitive transcranial magnetic stimulation on the ultrastructure of an ischemic brain penumbra and the expression of brain-derived neurotrophic factors in rats

    Institute of Scientific and Technical Information of China (English)

    黄杰; 马玉娟; 方征宇; 种玉飞; 随燕芳; 尤春景

    2011-01-01

    Objective To investigate the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) at different intensities on the ultrastructure of an ischemic brain penumbra and the expression of brainderived neurotrophic factor (BDNF) using rats with permanent middle cerebral artery occlusion (MCAO).Methods Forty-two rats were randomly divided into a blank control group,an MCAO model control group,a sham stimulation control group and an rTMS group.The rTMS group was divided further into 3 subgroups:an 80% of motor threshold (MT) subgroup,a 100% of MT subgroup and a 120% of MT subgroup.The cerebral infarction model was established by right MCAO.rTMS treatment was given 24 hours after the MCAO model was successfully established.The rTMS group and sham stimulation control group were given 20 Hz rTMS with the planned intensities.The MCAO model control group was not given any stimulation.After 14 days of treatment,transmission electron microscopy,immunohistochemical and Western blotting ( WB ) methods were used to investigate the ultrastructure of the ischemic penumbra and the expression of BDNF.Results Damage reflected in the ultrastructure in the 3 rTMS subgroups was less than in the model control group and the sham stimulation control group.Expression of BDNF protein increased significantly in 100% of the MT group and blank control group rats as compared with that in the sham stimulation control group,while the blank control group and the 3 rTMS subgroups had no statistically significant difference in comparison with the MCAO model control group.The expression of BDNF protein had no statistically significant difference between any of the groups.Conclusion 20 Hz rTMS might,especially at 100% of the MT,promote the recovery of the ultrastructure of neural tissues in the ischemic penumbra after acute cerebral infarction and enhance the expression of BDNF in the ipsilesional hemisphere.This may be one of the important mechanisms of r

  1. Functional promoter variant in zinc finger protein 202 predicts severe atherosclerosis and ischemic heart disease

    DEFF Research Database (Denmark)

    Frikke-Schmidt, R.; Nordestgaard, Børge; Grande, Peer

    2008-01-01

    Objectives This study was designed to test the hypotheses that single nucleotide polymorphisms ( SNPs), in zinc finger protein 202 ( ZNF202), predict severe atherosclerosis and ischemic heart disease ( IHD). Background ZNF202 is a transcriptional repressor controlling promoter elements in genes......,998 controls. Finally, we determined whether g. -660A>G altered transcriptional activity of the ZNF202 promoter in vitro. Results Cross-sectionally, ZNF202 g. -660 GG versus AA homozygosity predicted an odds ratio for severe atherosclerosis of 2.01 ( 95% confidence interval [CI]: 1.34 to 3.01). Prospectively...... were highly correlated with g. -660A>G, also predicted risk of severe atherosclerosis and IHD. Finally, ZNF202 g. -660G versus g. -660A was associated with a 60% reduction in transcriptional activity in vitro, whereas none of the 2 correlated SNPs were predicted to be functional. Conclusions...

  2. Multiparametric Magnetic Resonance Imaging for Prediction of Parenchymal Hemorrhage in Acute Ischemic Stroke After Reperfusion Therapy.

    Science.gov (United States)

    Nael, Kambiz; Knitter, James R; Jahan, Reza; Gornbein, Jeffery; Ajani, Zahra; Feng, Lei; Meyer, Brett C; Schwamm, Lee H; Yoo, Albert J; Marshall, Randolph S; Meyers, Philip M; Yavagal, Dileep R; Wintermark, Max; Liebeskind, David S; Guzy, Judy; Starkman, Sidney; Saver, Jeffrey L; Kidwell, Chelsea S

    2017-03-01

    Patients with acute ischemic stroke are at increased risk of developing parenchymal hemorrhage (PH), particularly in the setting of reperfusion therapies. We have developed a predictive model to examine the risk of PH using combined magnetic resonance perfusion and diffusion parameters, including cerebral blood volume (CBV), apparent diffusion coefficient, and microvascular permeability (K2). Voxel-based values of CBV, K2, and apparent diffusion coefficient from the ischemic core were obtained using pretreatment magnetic resonance imaging data from patients enrolled in the MR RESCUE clinical trial (Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy). The associations between PH and extreme values of imaging parameters were assessed in univariate and multivariate analyses. Receiver-operating characteristic curve analysis was performed to determine the optimal parameter(s) and threshold for predicting PH. In 83 patients included in this analysis, 20 developed PH. Univariate analysis showed significantly lower 10th percentile CBV and 10th percentile apparent diffusion coefficient values and significantly higher 90th percentile K2 values within the infarction core of patients with PH. Using classification tree analysis, the 10th percentile CBV at threshold of 0.47 and 90th percentile K2 at threshold of 0.28 resulted in overall predictive accuracy of 88.7%, sensitivity of 90.0%, and specificity of 87.3%, which was superior to any individual or combination of other classifiers. Our results suggest that combined 10th percentile CBV and 90th percentile K2 is an independent predictor of PH in patients with acute ischemic stroke with diagnostic accuracy superior to individual classifiers alone. This approach may allow risk stratification for patients undergoing reperfusion therapies. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00389467. © 2017 The Authors.

  3. The iScore predicts poor functional outcomes early after hospitalization for an acute ischemic stroke.

    Science.gov (United States)

    Saposnik, Gustavo; Raptis, Stavroula; Kapral, Moira K; Liu, Ying; Tu, Jack V; Mamdani, Muhammad; Austin, Peter C

    2011-12-01

    The iScore is a prediction tool originally developed to estimate the risk of death after hospitalization for an acute ischemic stroke. Our objective was to determine whether the iScore could also predict poor functional outcomes. We applied the iScore to patients presenting with an acute ischemic stroke at multiple hospitals in Ontario, Canada, between 2003 and 2008, who had been identified from the Registry of the Canadian Stroke Network regional stroke center database (n=3818) and from an external data set, the Registry of the Canadian Stroke Network Ontario Stroke Audit (n=4635). Patients were excluded if they were included in the sample used to develop and validate the initial iScore. Poor functional outcomes were defined as: (1) death at 30 days or disability at discharge, in which disability was defined as having a modified Rankin Scale 3 to 5; and (2) death at 30 days or institutionalization at discharge. The prevalence of poor functional outcomes in the Registry of the Canadian Stroke Network and the Ontario Stroke Audit, respectively, were 55.7% and 44.1% for death at 30 days or disability at discharge and 16.9% and 16.2%, respectively, for death at 30 days or institutionalization at discharge. The iScore stratified the risk of poor outcomes in low- and high-risk individuals. Observed versus predicted outcomes showed high correlations: 0.988 and 0.940 for mortality or disability and 0.985 and 0.993 for mortality or institutionalization in the Registry of the Canadian Stroke Network and Ontario Stroke Audit cohorts. The iScore can be used to estimate the risk of death or a poor functional outcome after an acute ischemic stroke.

  4. The effect of density on the 10MV photon beam penumbra.

    Science.gov (United States)

    Hoban, P W; Keal, P J; Round, W H

    1992-09-01

    An investigation into the density dependence of the penumbra of the Varian Clinac 18/10 10MV photon beam has been carried out. A water/lung phantom was constructed of polystyrene (r = 1.04 g cm-3) and cork (r = 0.23 g cm-3), in which interfaces exist both parallel and perpendicular to the beam axis. The irradiation of the phantom was also simulated using the EGS4 Monte Carlo system with a cartesian voxel geometry. Experimental (TLD) and Monte Carlo dose profiles are in close agreement, and show a large degree of penumbral broadening in the lung region. This broadening is due primarily to lateral electronic disequilibrium occurring at a larger distance from the geometric beam edge in lung than in water. This disequilibrium can also cause the dose in lung to drop below the dose in water at the same depth and off axis distance, even though the radiological depth is less in lung. Monte Carlo simulations were also performed where the dose is separated into primary and scattered components, for homogeneous media of densities 0.25, 0.50, 0.75 and 1.00 g cm-3. The penumbral width of the primary dose profile was found to be almost constant with depth for a point source of photons (after the initial build-up region), where the lateral distances from the 95-50% and 50-5% dose levels on the dose profile (normalised to the dose at the central axis) are equal in all cases. Also, primary penumbra width was found to be almost inversely proportional to density. The primary penumbra for a unit density material can be fitted accurately by an exponential forming function with empirical determined coefficients. The penumbral shape for the lower densities can then be closely fitted by scaling the coefficients in proportion to density. This scaling method has application in treatment planning, where the predicted primary penumbra shape should take account of inhomogeneities, and is particularly important in matching adjacent fields. When the scattered dose component is added to give the

  5. Models and observations of sunspot penumbrae

    Institute of Scientific and Technical Information of China (English)

    BORRERO; Juan; Manuel

    2009-01-01

    The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

  6. Models and Observations of Sunspot Penumbrae

    CERN Document Server

    Borrero, J M

    2008-01-01

    The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution. To help explaining these new observations I propose some modifications to each of them. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

  7. The predictive value of fatigue for nonfatal ischemic heart disease and all-cause mortality

    DEFF Research Database (Denmark)

    Ekmann, Anette; Osler, Merete; Avlund, Kirsten

    2012-01-01

    Objective To investigate whether fatigue predicts nonfatal ischemic heart disease (IHD) and all-cause mortality in middle-aged men. Methods The study population consisted of 5216 middle-aged men born in the Copenhagen metropolitan area in 1953. At baseline, men free of angina pectoris and previou...... is a potential risk indicator for IHD and mortality. Further research is needed to establish the role of smoking and other life-style characteristics.......% confidence interval [CI] = 1.09-3.61) and all-cause mortality (HR = 3.99, 95% CI = 2.27-7.02). These associations became nonsignificant in multivariable-adjusted models (HR = 1.57, 95% CI = 0.82-3.01 and HR = 1.90, 95% CI = 0.95-3.80). Imputation of missing data did not modify conclusions. Fatigue...

  8. Blood-Brain Barrier Permeability Assessed by Perfusion CT Predicts Symptomatic Hemorrhagic Transformation and Malignant Edema in Acute Ischemic Stroke

    NARCIS (Netherlands)

    Hom, J.; Dankbaar, J. W.; Soares, B. P.; Schneider, T.; Cheng, S. -C.; Bredno, J.; Lau, B. C.; Smith, W.; Dillon, W. P.; Wintermark, M.

    2011-01-01

    BACKGROUND AND PURPOSE: SHT and ME are feared complications in patients with acute ischemic stroke. They occur >10 times more frequently in tPA-treated versus placebo-treated patients. Our goal was to evaluate the sensitivity and specificity of admission BBBP measurements derived from PCT in predict

  9. Influence of eye acupuncture therapy in expressions of BDNF and TrkB in corresponding penumbra brain tissue of ischemic area in rats with acute cerebral ischemia-reperfusion inj ury%眼针对MCAO/R大鼠大脑缺血区半暗带脑组织中BDNF和TrkB表达的影响及其脑保护作用机制

    Institute of Scientific and Technical Information of China (English)

    马贤德; 侯殿东; 张威

    2014-01-01

    目的:观察眼针对局灶性大脑中动脉缺血再灌注(MCAO/R)模型大鼠大脑缺血区半暗带脑组织中脑原性神经生长因子(BDNF)和酪氨酸激酶受体B(TrkB)表达水平的影响,探讨眼针对缺血性脑病的脑保护作用机制。方法:62只SD大鼠随机分为空白对照组(11只)、假手术组(11只)和模型复制组(40只)。模型复制组大鼠采用线栓法建立脑缺血再灌注模型,将模型复制成功的大鼠(32只)随机分为模型组(16只)及眼针组(16只);眼针组大鼠参照人体取穴方法,取肝区、上焦区、下焦区和肾区进行针刺干预。再灌注后2h即开始针刺,每8h 1次,连续针刺10次,末次干预后30 min,断髓处死大鼠,剥离缺血区域周围半暗带部位的脑组织,采用 RT-PCR和 Western blotting法检测大鼠脑组织中 BDNF和 TrkB mRNA及蛋白表达水平。结果:与空白对照组比较,假手术组大鼠半暗带脑组织中BDNF和TrkB mRNA和蛋白表达水平均无明显变化(P>0.05);与假手术组比较,模型组大鼠半暗带脑组织中BDNF和TrkB mRNA和蛋白表达水平均升高(P<0.01);与模型组比较,眼针组 MCAO/R模型大鼠半暗带脑组织中 BDNF和 TrkB mRNA和蛋白表达水平上升(P<0.05或P<0.01)。结论:脑缺血再灌注损伤发生后可促进 BDNF及其受体 TrkB表达以对抗损伤。眼针可通过上调 BDNF及其受体TrkB表达水平实现其脑保护作用。%Objective To investigate the influence of the eye acupuncture therapy in the expressions of brain derived neurophic factor(BDNF)and tyrosine kinase receptor B(TrkB)in penumbra brain tissue of ischemic area in the rats with acute cerebral ischemia reperfusion inj ury,and to explore the related mechanism of protective effect on brain of eye acupunture.Methods 62 SD rats were randomly divided into blank control group (n=11),sham operation group (n=11)and model copy

  10. Hemostatic system changes predictive value in patients with ischemic brain disorders

    Directory of Open Access Journals (Sweden)

    Raičević Ranko

    2002-01-01

    Full Text Available The aim of this research was to determine the importance of tracking the dynamics of changes of the hemostatic system factors (aggregation of thrombocytes, D-dimer, PAI-1, antithrombin III, protein C and protein S, factor VII and factor VIII, fibrin degradation products, euglobulin test and the activated partial thromboplastin time – aPTPV in relation to the level of the severity of ischemic brain disorders (IBD and the level of neurological and functional deficiency in the beginning of IBD manifestation from 7 to 10 days, 19 to 21 day, and after 3 to 6 months. The research results confirmed significant predictive value of changes of hemostatic system with the predomination of procoagulant factors, together with the insufficiency of fibrinolysis. Concerning the IBD severity and it's outcome, the significant predictive value was shown in the higher levels of PAI-1 and the lower level of antithrombin III, and borderline significant value was shown in the accelerated aggregation of thrombocytes and the increased concentration of D-dimer. It could be concluded that the tracking of the dynamics of changes in parameters of hemostatic system proved to be an easily accessible method with the significant predictive value regarding the development of more severe. IBD cases and the outcome of the disease itself.

  11. Inflammatory and metalloproteinases profiles predict three-month poor outcomes in ischemic stroke treated with thrombolysis.

    Science.gov (United States)

    Gori, Anna Maria; Giusti, Betti; Piccardi, Benedetta; Nencini, Patrizia; Palumbo, Vanessa; Nesi, Mascia; Nucera, Antonia; Pracucci, Giovanni; Tonelli, Paolina; Innocenti, Eleonora; Sereni, Alice; Sticchi, Elena; Toni, Danilo; Bovi, Paolo; Guidotti, Mario; Tola, Maria Rosaria; Consoli, Domenico; Micieli, Giuseppe; Tassi, Rossana; Orlandi, Giovanni; Sessa, Maria; Perini, Francesco; Delodovici, Maria Luisa; Zedde, Maria Luisa; Massaro, Francesca; Abbate, Rosanna; Inzitari, Domenico

    2017-09-01

    Inflammatory mediators and metalloproteinases are altered in acute ischemic stroke (AIS) and play a detrimental effect on clinical severity and hemorrhagic transformation of the ischemic brain lesion. Using data from the Italian multicenter observational MAGIC (MArker bioloGici nell'Ictus Cerebrale) Study, we evaluated the effect of inflammatory and metalloproteinases profiles on three-month functional outcome, hemorrhagic transformation and mortality in 327 patients with AIS treated with intravenous thrombolys in according to SITS-MOST (Safe Implementation of Thrombolysis in Stroke-MOnitoring STudy) criteria. Circulating biomarkers were assessed at baseline and 24 h after thrombolysis. Adjusting for age, sex, baseline glycemia and National Institute of Health Stroke Scale, history of atrial fibrillation or congestive heart failure, and of inflammatory diseases or infections, baseline alpha-2macroglobulin (A2M), baseline serum amyloid protein (SAP) and pre-post tissue-plasminogen activator (tPA) variations (Δ) of metalloproteinase 9, remained significantly and independently associated with three-month death [OR (95% CI):A2M:2.99 (1.19-7.53); SAP:5.46 (1.64-18.74); Δmetalloproteinase 9:1.60 (1.12-2.27)]. The addition of baseline A2M and Δmetalloproteinase 9 or baseline SAP and Δmetalloproteinase 9 (model-2 or model-3) to clinical variables (model-1) significantly improved the area under curve for prediction of death [model-2 with A2M: p = 0.0205; model-3 with SAP: p = 0.001]. In conclusion, among AIS patients treated with thrombolysis, circulating A2M, SAP and Δmetalloproteinase 9 are independent markers of poor outcome. These results may prompt controlled clinical research about agents antagonizing their effect.

  12. Early clinical signs in neonates with hypoxic ischemic encephalopathy predict an abnormal amplitude-integrated electroencephalogram at age 6 hours

    OpenAIRE

    Horn, Alan R; Swingler, George H; Myer, Landon; Linley, Lucy L; Raban, Moegammad S; Joolay, Yaseen; Harrison, Michael C; Chandrasekaran, Manigandan; Rhoda, Natasha R; Robertson, Nicola J.

    2013-01-01

    Background An early clinical score predicting an abnormal amplitude-integrated electroencephalogram (aEEG) or moderate-severe hypoxic ischemic encephalopathy (HIE) may allow rapid triage of infants for therapeutic hypothermia. We aimed to determine if early clinical examination could predict either an abnormal aEEG at age 6 hours or moderate-severe HIE presenting within 72 hours of birth. Methods Sixty infants ≥ 36 weeks gestational age were prospectively enrolled following suspected intrapar...

  13. Validating a Predictive Model of Acute Advanced Imaging Biomarkers in Ischemic Stroke.

    Science.gov (United States)

    Bivard, Andrew; Levi, Christopher; Lin, Longting; Cheng, Xin; Aviv, Richard; Spratt, Neil J; Lou, Min; Kleinig, Tim; O'Brien, Billy; Butcher, Kenneth; Zhang, Jingfen; Jannes, Jim; Dong, Qiang; Parsons, Mark

    2017-03-01

    Advanced imaging to identify tissue pathophysiology may provide more accurate prognostication than the clinical measures used currently in stroke. This study aimed to derive and validate a predictive model for functional outcome based on acute clinical and advanced imaging measures. A database of prospectively collected sub-4.5 hour patients with ischemic stroke being assessed for thrombolysis from 5 centers who had computed tomographic perfusion and computed tomographic angiography before a treatment decision was assessed. Individual variable cut points were derived from a classification and regression tree analysis. The optimal cut points for each assessment variable were then used in a backward logic regression to predict modified Rankin scale (mRS) score of 0 to 1 and 5 to 6. The variables remaining in the models were then assessed using a receiver operating characteristic curve analysis. Overall, 1519 patients were included in the study, 635 in the derivation cohort and 884 in the validation cohort. The model was highly accurate at predicting mRS score of 0 to 1 in all patients considered for thrombolysis therapy (area under the curve [AUC] 0.91), those who were treated (AUC 0.88) and those with recanalization (AUC 0.89). Next, the model was highly accurate at predicting mRS score of 5 to 6 in all patients considered for thrombolysis therapy (AUC 0.91), those who were treated (0.89) and those with recanalization (AUC 0.91). The odds ratio of thrombolysed patients who met the model criteria achieving mRS score of 0 to 1 was 17.89 (4.59-36.35, Pischemic stroke. © 2017 American Heart Association, Inc.

  14. Improving prediction of ischemic cardiovascular disease in the general population using apolipoprotein B

    DEFF Research Database (Denmark)

    Benn, M; Nordestgaard, B; Jensen, Gorm Boje

    2007-01-01

    events than low-density lipoprotein cholesterol. Methods and Results- We studied 9231 asymptomatic women and men from the Danish general population followed prospectively for 8 years and observed the following incident events: ischemic heart disease 591, myocardial infarction 278, ischemic...

  15. A specific dietary intervention to restore brain structure and function after ischemic stroke

    NARCIS (Netherlands)

    Wiesmann, M.; Zinnhardt, B.; Reinhardt, D.; Eligehausen, S.; Wachsmuth, L.; Hermann, S.; Dederen, P.J.; Hellwich, M.; Kuhlmann, M.T.; Broersen, L.M.; Heerschap, A.; Jacobs, A.H.; Kiliaan, A.J.

    2017-01-01

    Occlusion of the middle cerebral artery (MCAo) is among the most common causes of ischemic stroke in humans. Cerebral ischemia leads to brain lesions existing of an irreversibly injured core and an ischemic boundary zone, the penumbra, containing damaged but potentially salvageable tissue. Using a t

  16. Detection of sea-serpent field lines in sunspot penumbrae

    CERN Document Server

    Dalda, A Sainz

    2007-01-01

    We investigate the spatial distribution of magnetic polarities in the penumbra of a spot observed very close to disk center. High-spatial resolution, high-cadence magnetograms taken with the Narrowband Filter Imager aboard Hinode are used in this study. They provide continuous and stable measurements in the photospheric Fe I 630.25 line for long periods of time. We discover small-scale, elongated, bipolar magnetic structures that appear in the mid penumbra and move radially outward across the penumbra. They occur in between the more vertical fields of the penumbra, and can be associated with the horizontal fields that harbor the Evershed flow. Many of them cross the outer penumbral boundary, becoming moving magnetic features in the sunspot moat. We determine the properties of these structures, including their sizes, proper motions, footpoint separation, and lifetimes. The bipolar patches can be interpreted as being produced by sea-serpent field lines that originate in the mid-penumbra and eventually leave the...

  17. Automated prediction of tissue outcome after acute ischemic stroke in computed tomography perfusion images

    Science.gov (United States)

    Vos, Pieter C.; Bennink, Edwin; de Jong, Hugo; Velthuis, Birgitta K.; Viergever, Max A.; Dankbaar, Jan Willem

    2015-03-01

    Assessment of the extent of cerebral damage on admission in patients with acute ischemic stroke could play an important role in treatment decision making. Computed tomography perfusion (CTP) imaging can be used to determine the extent of damage. However, clinical application is hindered by differences among vendors and used methodology. As a result, threshold based methods and visual assessment of CTP images has not yet shown to be useful in treatment decision making and predicting clinical outcome. Preliminary results in MR studies have shown the benefit of using supervised classifiers for predicting tissue outcome, but this has not been demonstrated for CTP. We present a novel method for the automatic prediction of tissue outcome by combining multi-parametric CTP images into a tissue outcome probability map. A supervised classification scheme was developed to extract absolute and relative perfusion values from processed CTP images that are summarized by a trained classifier into a likelihood of infarction. Training was performed using follow-up CT scans of 20 acute stroke patients with complete recanalization of the vessel that was occluded on admission. Infarcted regions were annotated by expert neuroradiologists. Multiple classifiers were evaluated in a leave-one-patient-out strategy for their discriminating performance using receiver operating characteristic (ROC) statistics. Results showed that a RandomForest classifier performed optimally with an area under the ROC of 0.90 for discriminating infarct tissue. The obtained results are an improvement over existing thresholding methods and are in line with results found in literature where MR perfusion was used.

  18. The iScore predicts total healthcare costs early after hospitalization for an acute ischemic stroke.

    Science.gov (United States)

    Ewara, Emmanuel M; Isaranuwatchai, Wanrudee; Bravata, Dawn M; Williams, Linda S; Fang, Jiming; Hoch, Jeffrey S; Saposnik, Gustavo

    2015-12-01

    The ischemic Stroke risk score is a validated prognostic score which can be used by clinicians to estimate patient outcomes after the occurrence of an acute ischemic stroke. In this study, we examined the association between the ischemic Stroke risk score and patients' 30-day, one-year, and two-year healthcare costs from the perspective of a third party healthcare payer. Patients who had an acute ischemic stroke were identified from the Registry of Canadian Stroke Network. The 30-day ischemic Stroke risk score prognostic score was determined for each patient. Direct healthcare costs at each time point were determined using administrative databases in the province of Ontario. Unadjusted mean and the impact of a 10-point increase ischemic Stroke risk score and a patient's risk of death or disability on total cost were determined. There were 12,686 patients eligible for the study. Total unadjusted mean costs were greatest among patients at high risk. When adjusting for patient characteristics, a 10-point increase in the ischemic Stroke risk score was associated with 8%, 7%, and 4% increase in total costs at 30 days, one-year, and two-years. The same increase was found to impact patients at low, medium, and high risk differently. When adjusting for patient characteristics, patients in the high-risk group had the highest total costs at 30 days, while patients at medium risk had the highest costs at both one and two-years. The ischemic Stroke risk score can be useful as a predictor of healthcare utilization and costs early after hospitalization for an acute ischemic stroke. © 2015 World Stroke Organization.

  19. Optical Spectroscopy Approach for the Predictive Assessment of Kidney Functional Recovery Following Ischemic Injury

    Energy Technology Data Exchange (ETDEWEB)

    Raman, R N; Pivetti, C D; Rubenchik, A M; Matthews, D L; Troppmann, C; Demos, S G

    2010-02-11

    Tissue that has undergone significant yet unknown amount of ischemic injury is frequently encountered in organ transplantation and trauma clinics. With no reliable real-time method of assessing the degree of injury incurred in tissue, surgeons generally rely on visual observation which is subjective. In this work, we investigate the use of optical spectroscopy methods as a potentially more reliable approach. Previous work by various groups was strongly suggestive that tissue autofluorescence from NADH obtained under UV excitation is sensitive to metabolic response changes. To test and expand upon this concept, we monitored autofluorescence and light scattering intensities of injured vs. uninjured rat kidneys via multimodal imaging under 355 nm, 325 nm, and 266 nm excitation as well as scattering under 500 nm illumination. 355 nm excitation was used to probe mainly NADH, a metabolite, while 266 nm excitation was used to probe mainly tryptophan to correct for non-metabolic signal artifacts. The ratio of autofluorescence intensities derived under these two excitation wavelengths was calculated and its temporal profile was fit to a relaxation model. Time constants were extracted, and longer time constants were associated with kidney dysfunction. Analysis of both the autofluorescence and light scattering images suggests that changes in microstructure tissue morphology, blood absorption spectral characteristics, and pH contribute to the behavior of the observed signal which may be used to obtain tissue functional information and offer predictive capability.

  20. Monocyte/high-density lipoprotein ratio predicts the mortality in ischemic stroke patients.

    Science.gov (United States)

    Bolayir, Asli; Gokce, Seyda Figul; Cigdem, Burhanettin; Bolayir, Hasan Ata; Yildiz, Ozlem Kayim; Bolayir, Ertugrul; Topaktas, Suat Ahmet

    2017-08-24

    The inflammatory process is a very important stage in the development and prognosis of acute ischemic stroke (AIS). The monocyte to high-density lipoprotein (HDL) ratio (MHR) is accepted as a novel marker for demonstrating inflammation. However, the role of MHR as a predictor of mortality in patients with AIS remains unclear. We retrospectively enrolled 466 patients who were referred to our clinic within the first 24hours of symptom presentation and who were diagnosed with AIS between January 2008 and June 2016. Four hundred and eight controls of similar age and gender were also included. The patient group was classified into two groups according to 30-day mortality. The groups were compared in terms of monocyte counts, HDL, and MHR values. The patient group had significantly higher monocyte counts and lower HDL levels; therefore, this group had higher values of MHR compared to controls. Additionally, the monocyte count and MHR value were higher, and the HDL level was lower in non-surviving patients (pMHR value was also observed as a significant independent variable of 30-day mortality in patients with AIS (pMHR in predicting the 30-day mortality for patients with AIS was 17.52 (95% CI 0.95-0.98). Our study demonstrated that a high MHR value is an independent predictor of 30-day mortality in patients with AIS. Copyright © 2017 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  1. Flare induced penumbra formation in the sunspot of NOAA 10838

    CERN Document Server

    Padinhatteeri, Sreejith

    2010-01-01

    We have observed formation of penumbrae on a pore in the active region NOAA10838 using Dunn Solar Telescope at NSO,Sunpot,USA. Simultaneous observations using different instruments (DLSP,UBF,Gband and CaK) provide us with vector magnetic field at photosphere, intensity images and Doppler velocity at different heights from photosphere to chromosphere. Results from our analysis of this particular data-set suggests that penumbrae are formed as a result of relaxation of magnetic field due to a flare happening at the same time. Images in \\Halpha\\ show the flare (C 2.9 as per GOES) and vector magnetic fields show a re-orientation and reduction in the global $\\alpha$ value (a measure of twist). We feel such relaxation of loop structures due to reconnections or flare could be one of the way by which field lines fall back to the photosphere to form penumbrae.

  2. Collateral blood vessels in acute ischemic stroke: a physiological window to predict future outcomes.

    Science.gov (United States)

    Alves, Heitor Castelo Branco Rodrigues; Pacheco, Felipe Torres; Rocha, Antonio J

    2016-08-01

    Collateral circulation is a physiologic pathway that protects the brain against ischemic injury and can potentially bypass the effect of a blocked artery, thereby influencing ischemic lesion size and growth. Several recent stroke trials have provided information about the role of collaterals in stroke pathophysiology, and collateral perfusion has been recognized to influence arterial recanalization, reperfusion, hemorrhagic transformation, and neurological outcomes after stroke. Our current aim is to summarize the anatomy and physiology of the collateral circulation and to present and discuss a comprehensible review of the related knowledge, particularly the effects of collateral circulation on the time course of ischemic injury and stroke severity, as well as imaging findings and therapeutic implications.

  3. The role of THRIVE score in prediction of outcomes of acute ischemic stroke patients with atrial fibrillation

    Institute of Scientific and Technical Information of China (English)

    尤寿江

    2014-01-01

    Objective To study whether the total health risks in vascular events(THRIVE)score could predict the prognosis in the acute ischemic stroke patients with atrial fibrillation.Methods A total of 169 patients were enrolled in the study,with NIH Stroke Scale(NIHSS)score,THRIVE score and CHADS2score given to each patients at admission and modified Rankin Scale(mRS)given at3 months follow up.All patients were divided into the

  4. Flare induced penumbra formation in the sunspot of NOAA 10838

    OpenAIRE

    Padinhatteeri, Sreejith; K., Sankarasubramanian

    2010-01-01

    We have observed formation of penumbrae on a pore in the active region NOAA10838 using Dunn Solar Telescope at NSO,Sunpot,USA. Simultaneous observations using different instruments (DLSP,UBF,Gband and CaK) provide us with vector magnetic field at photosphere, intensity images and Doppler velocity at different heights from photosphere to chromosphere. Results from our analysis of this particular data-set suggests that penumbrae are formed as a result of relaxation of magnetic field due to a fl...

  5. Genetic variation in ABCA1 predicts ischemic heart disease in the general population

    DEFF Research Database (Denmark)

    Frikke-Schmidt, Ruth; Nordestgaard, Børge G; Jensen, Gorm B;

    2008-01-01

    We tested the hypothesis that 6 nonsynonymous single nucleotide polymorphisms (SNPs) in ATP-Binding-Cassette transporter A1 (ABCA1) affect risk of ischemic heart disease (IHD) in the general population....

  6. Spatio-Temporal Variation and Prediction of Ischemic Heart Disease Hospitalizations in Shenzhen, China

    Directory of Open Access Journals (Sweden)

    Yanxia Wang

    2014-05-01

    Full Text Available Ischemic heart disease (IHD is a leading cause of death worldwide. Urban public health and medical management in Shenzhen, an international city in the developing country of China, is challenged by an increasing burden of IHD. This study analyzed the spatio-temporal variation of IHD hospital admissions from 2003 to 2012 utilizing spatial statistics, spatial analysis, and space-time scan statistics. The spatial statistics and spatial analysis measured the incidence rate (hospital admissions per 1,000 residents and the standardized rate (the observed cases standardized by the expected cases of IHD at the district level to determine the spatio-temporal distribution and identify patterns of change. The space-time scan statistics was used to identify spatio-temporal clusters of IHD hospital admissions at the district level. The other objective of this study was to forecast the IHD hospital admissions over the next three years (2013–2015 to predict the IHD incidence rates and the varying burdens of IHD-related medical services among the districts in Shenzhen. The results show that the highest hospital admissions, incidence rates, and standardized rates of IHD are in Futian. From 2003 to 2012, the IHD hospital admissions exhibited similar mean centers and directional distributions, with a slight increase in admissions toward the north in accordance with the movement of the total population. The incidence rates of IHD exhibited a gradual increase from 2003 to 2012 for all districts in Shenzhen, which may be the result of the rapid development of the economy and the increasing traffic pollution. In addition, some neighboring areas exhibited similar temporal change patterns, which were also detected by the spatio-temporal cluster analysis. Futian and Dapeng would have the highest and the lowest hospital admissions, respectively, although these districts have the highest incidence rates among all of the districts from 2013 to 2015 based on the prediction

  7. Spatio-Temporal Variation and Prediction of Ischemic Heart Disease Hospitalizations in Shenzhen, China

    Science.gov (United States)

    Wang, Yanxia; Du, Qingyun; Ren, Fu; Liang, Shi; Lin, De-nan; Tian, Qin; Chen, Yan; Li, Jia-jia

    2014-01-01

    Ischemic heart disease (IHD) is a leading cause of death worldwide. Urban public health and medical management in Shenzhen, an international city in the developing country of China, is challenged by an increasing burden of IHD. This study analyzed the spatio-temporal variation of IHD hospital admissions from 2003 to 2012 utilizing spatial statistics, spatial analysis, and space-time scan statistics. The spatial statistics and spatial analysis measured the incidence rate (hospital admissions per 1,000 residents) and the standardized rate (the observed cases standardized by the expected cases) of IHD at the district level to determine the spatio-temporal distribution and identify patterns of change. The space-time scan statistics was used to identify spatio-temporal clusters of IHD hospital admissions at the district level. The other objective of this study was to forecast the IHD hospital admissions over the next three years (2013–2015) to predict the IHD incidence rates and the varying burdens of IHD-related medical services among the districts in Shenzhen. The results show that the highest hospital admissions, incidence rates, and standardized rates of IHD are in Futian. From 2003 to 2012, the IHD hospital admissions exhibited similar mean centers and directional distributions, with a slight increase in admissions toward the north in accordance with the movement of the total population. The incidence rates of IHD exhibited a gradual increase from 2003 to 2012 for all districts in Shenzhen, which may be the result of the rapid development of the economy and the increasing traffic pollution. In addition, some neighboring areas exhibited similar temporal change patterns, which were also detected by the spatio-temporal cluster analysis. Futian and Dapeng would have the highest and the lowest hospital admissions, respectively, although these districts have the highest incidence rates among all of the districts from 2013 to 2015 based on the prediction using the GM (1

  8. Predictive value of stroke and transient ischemic attack discharge diagnoses in the Danish National Registry of Patients

    DEFF Research Database (Denmark)

    Johnsen, Søren P; Overvad, Kim; Sørensen, Henrik Toft;

    2002-01-01

    We examined the predictive value of the discharge diagnoses of stroke and transient ischemic attack (TIA) in The National Registry of Patients (NRP) for participants in the Danish cohort study “Diet, Cancer, and Health.” We retrieved all probable incident registered cases of stroke and TIA, i...... and intracerebral hemorrhage were confirmed in 14 of 29 cases (48.3%, 95% CI: 29.4–67.5%), and 23 of 35 cases (65.7%, 95% CI: 47.8–80.9%), respectively. By contrast, ischemic stroke and unspecified stroke were confirmed in 99 of 113 cases (87.6%, 95% CI: 80.1–93.1%) and 152 of 200 cases (76.0%, 95% CI: 69...

  9. Formation of the penumbra and start of the Evershed flow

    CERN Document Server

    Murabito, M; Gugliemino, S L; Zuccarello, F; Solanki, S K

    2016-01-01

    We studied the variations of line-of-sight photospheric plasma flows during the formation phase of the penumbra around a pore in Active Region NOAA 11490. We used a high spatial, spectral, and temporal resolution data set acquired by the Interferometric BIdimensional Spectrometer (IBIS) operating at the NSO/Dunn Solar Telescope as well as data taken by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory satellite (SDO/HMI). Before the penumbra formed we observed a redshift of the spectral line in the inner part of the annular zone surrounding the pore as well as a blueshift of material associated with opposite magnetic polarity further away from the pore. We found that the onset of the classical Evershed flow occurs in a very short time scale -- 1-3 hours -- while the penumbra is forming. During the same time interval we found changes in the magnetic field inclination in the penumbra, with the vertical field actually changing sign near the penumbral edge, while the total magnetic field...

  10. The formation of sunspot penumbra. I. Magnetic field properties

    CERN Document Server

    Rezaei, Reza; Schlichenmaier, Rolf

    2011-01-01

    We study the formation of a sunspot penumbra in the active region NOAA11024. We simultaneously observed the Stokes parameters of the photospheric iron lines at 1089.6 nm with the TIP and 617.3 nm with the GFPI spectropolarimeters along with broad-band images using G-band and CaIIK filters at the German VTT. The formation of the penumbra is intimately related to the inclined magnetic field. Within 4.5 h observing time, the magnetic flux of the penumbra increases from 9.7E+20 to 18.2E+20 Mx, while the magnetic flux of the umbra remains constant at about 3.8E+20 Mx. Magnetic flux in the immediate surroundings is incorporated into the spot, and new flux is supplied via small flux patches (SFPs), which on average have a flux of 2-3E+18 Mx. The spot's flux increase rate of 4.2E+16 Mx/s corresponds to the merging of one SFP per minute. We also find that during the formation of the spot penumbra: a) the maximum magnetic field strength of the umbra does not change, b) the magnetic neutral line keeps the same position ...

  11. Inclination of magnetic fields and flows in sunspot penumbrae

    Science.gov (United States)

    Langhans, K.; Scharmer, G. B.; Kiselman, D.; Löfdahl, M. G.; Berger, T. E.

    2005-06-01

    An observational study of the inclination of magnetic fields and flows in sunspot penumbrae at a spatial resolution of 0.2 arcsec is presented. The analysis is based on longitudinal magnetograms and Dopplergrams obtained with the Swedish 1-m Solar Telescope on La Palma using the Lockheed Solar Optical Universal Polarimeter birefringent filter. Data from two sunspots observed at several heliocentric angles between 12 ° and 39 ° were analyzed. We find that the magnetic field at the level of the formation of the Fe i-line wing (630.25 nm) is in the form of coherent structures that extend radially over nearly the entire penumbra giving the impression of vertical sheet-like structures. The inclination of the field varies up to 45 ° over azimuthal distances close to the resolution limit of the magnetograms. Dark penumbral cores, and their extensions into the outer penumbra, are prominent features associated with the more horizontal component of the magnetic field. The inclination of this dark penumbral component - designated B - increases outwards from approximately 40 ° in the inner penumbra such that the field lines are nearly horizontal or even return to the solar surface already in the middle penumbra. The bright component of filaments - designated A - is associated with the more vertical component of the magnetic field and has an inclination with respect to the normal of about 35 ° in the inner penumbra, increasing to about 60 ° towards the outer boundary. The magnetogram signal is lower in the dark component B regions than in the bright component A regions of the penumbral filaments. The measured rapid azimuthal variation of the magnetogram signal is interpreted as being caused by combined fluctuations of inclination and magnetic field strength. The Dopplergrams show that the velocity field associated with penumbral component B is roughly aligned with the magnetic field while component A flows are more horizontal than the magnetic field. The observations give

  12. Comparison of classification methods for voxel-based prediction of acute ischemic stroke outcome following intra-arterial intervention

    Science.gov (United States)

    Winder, Anthony J.; Siemonsen, Susanne; Flottmann, Fabian; Fiehler, Jens; Forkert, Nils D.

    2017-03-01

    Voxel-based tissue outcome prediction in acute ischemic stroke patients is highly relevant for both clinical routine and research. Previous research has shown that features extracted from baseline multi-parametric MRI datasets have a high predictive value and can be used for the training of classifiers, which can generate tissue outcome predictions for both intravenous and conservative treatments. However, with the recent advent and popularization of intra-arterial thrombectomy treatment, novel research specifically addressing the utility of predictive classi- fiers for thrombectomy intervention is necessary for a holistic understanding of current stroke treatment options. The aim of this work was to develop three clinically viable tissue outcome prediction models using approximate nearest-neighbor, generalized linear model, and random decision forest approaches and to evaluate the accuracy of predicting tissue outcome after intra-arterial treatment. Therefore, the three machine learning models were trained, evaluated, and compared using datasets of 42 acute ischemic stroke patients treated with intra-arterial thrombectomy. Classifier training utilized eight voxel-based features extracted from baseline MRI datasets and five global features. Evaluation of classifier-based predictions was performed via comparison to the known tissue outcome, which was determined in follow-up imaging, using the Dice coefficient and leave-on-patient-out cross validation. The random decision forest prediction model led to the best tissue outcome predictions with a mean Dice coefficient of 0.37. The approximate nearest-neighbor and generalized linear model performed equally suboptimally with average Dice coefficients of 0.28 and 0.27 respectively, suggesting that both non-linearity and machine learning are desirable properties of a classifier well-suited to the intra-arterial tissue outcome prediction problem.

  13. Collateral blood vessels in acute ischemic stroke: a physiological window to predict future outcomes

    Directory of Open Access Journals (Sweden)

    Heitor Castelo Branco Rodrigues Alves

    2016-01-01

    Full Text Available ABSTRACT Collateral circulation is a physiologic pathway that protects the brain against ischemic injury and can potentially bypass the effect of a blocked artery, thereby influencing ischemic lesion size and growth. Several recent stroke trials have provided information about the role of collaterals in stroke pathophysiology, and collateral perfusion has been recognized to influence arterial recanalization, reperfusion, hemorrhagic transformation, and neurological outcomes after stroke. Our current aim is to summarize the anatomy and physiology of the collateral circulation and to present and discuss a comprehensible review of the related knowledge, particularly the effects of collateral circulation on the time course of ischemic injury and stroke severity, as well as imaging findings and therapeutic implications.

  14. Increased blood-brain barrier permeability on perfusion computed tomography predicts hemorrhagic transformation in acute ischemic stroke.

    Science.gov (United States)

    Ozkul-Wermester, Ozlem; Guegan-Massardier, Evelyne; Triquenot, Aude; Borden, Alaina; Perot, Guillaume; Gérardin, Emmanuel

    2014-01-01

    Perfusion computed tomography (CT) is capable of measuring the permeability surface product (PS). PS reflects the permeability of the blood-brain barrier, involved in the pathophysiology of hemorrhagic transformation (HT) of ischemic stroke. The aim of our study was to determine if an increased PS can predict HT. A total of 86 patients with ischemic stroke were included. They underwent multimodality CT, including the measurement of PS. We compared the clinical and radiological characteristics of patients who developed HT to those who did not, using univariate analysis. Multivariate regression analyses were then used to determine HT predictors. HT was observed in 27 patients (31%). Infarct PS was significantly associated with HT (p = 0.047), as were atrial fibrillation (p = 0.03), admission National Institute of Health Stroke Scale score (p = 0.02), infarct volume (p = 0.0004), presence of large-vessel occlusion (p = 0.0005) and a poorer collateral status (p = 0.003). Using logistic regression modeling, an infarct PS >0.84 ml/100 g/min was an independent predictor of HT (OR 28, 95% CI 1.75-452.98; p = 0.02). Other independent predictors of HT were infarct volume and a history of atrial fibrillation. Our findings suggest that infarct PS can be a predictor of HT and may help clinicians to improve patient care around thrombolysis decisions in the acute phase of ischemic stroke. © 2014 S. Karger AG, Basel.

  15. CT perfusion analysis by nonlinear regression for predicting hemorrhagic transformation in ischemic stroke

    NARCIS (Netherlands)

    Bennink, Edwin; Horsch, Alexander D.; Dankbaar, Jan Willem; Velthuis, BK; Viergever, Max A.; de Jong, Hugo W. A. M.

    2015-01-01

    Purpose: Intravenous thrombolysis can improve clinical outcome in acute ischemic stroke patients but increases the risk of hemorrhagic transformation (HT). Blood-brain barrier damage, which can be quantified by the vascular permeability for contrast agents, is a potential predictor for HT. This stud

  16. Defining acute ischemic stroke tissue pathophysiology with whole brain CT perfusion.

    Science.gov (United States)

    Bivard, A; Levi, C; Krishnamurthy, V; Hislop-Jambrich, J; Salazar, P; Jackson, B; Davis, S; Parsons, M

    2014-12-01

    This study aimed to identify and validate whole brain perfusion computed tomography (CTP) thresholds for ischemic core and salvageable penumbra in acute stroke patients and develop a probability based model to increase the accuracy of tissue pathophysiology measurements. One hundred and eighty-three patients underwent multimodal stroke CT using a 320-slice scanner within 6hours of acute stroke onset, followed by 24hour MRI that included diffusion weighted imaging (DWI) and dynamic susceptibility weighted perfusion imaging (PWI). Coregistered acute CTP and 24hour DWI was used to identify the optimum single perfusion parameter thresholds to define penumbra (in patients without reperfusion), and ischemic core (in patients with reperfusion), using a pixel based receiver operator curve analysis. Then, these results were used to develop a sigma curve fitted probability based model incorporating multiple perfusion parameter thresholds. For single perfusion thresholds, a time to peak (TTP) of +5seconds best defined the penumbra (area under the curve, AUC 0.79 CI 0.74-0.83) while a cerebral blood flow (CBF) of acute ischemic core (AUC 0.73, CI 0.69-0.77). The probability model was more accurate at detecting the ischemic core (AUC 0.80 SD 0.75-0.83) and penumbra (0.85 SD 0.83-0.87) and was significantly closer in volume to the corresponding reference DWI (P=0.031). Whole brain CTP can accurately identify penumbra and ischemic core using similar thresholds to previously validated 16 or 64 slice CTP. Additionally, a novel probability based model was closer to defining the ischemic core and penumbra than single thresholds. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  17. Quantitative characterization of myocardial infarction by cardiovascular magnetic resonance predicts future cardiovascular events in patients with ischemic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Pauly John M

    2008-04-01

    Full Text Available Abstract Background Cardiovascular magnetic resonance (CMR can provide quantitative data of the myocardial tissue utilizing high spatial and temporal resolution along with exquisite tissue contrast. Previous studies have correlated myocardial scar tissue with the occurrence of ventricular arrhythmia. This study was conducted to evaluate whether characterization of myocardial infarction by CMR can predict cardiovascular events in patients with ischemic cardiomyopathy (ICM. Results We consecutively studied 86 patients with ICM (LVEF Conclusion Quantification of the scar volume and scar percentage by CMR is superior to LVEDV, LVESV, and LVEF in prognosticating the future likelihood of the development of cardiovascular events in patients with ICM.

  18. Peculiarity of the oscillation stratification in sunspot penumbrae

    CERN Document Server

    Kolobov, D Y; Kobanov, N I

    2016-01-01

    Spatial distributions of the dominant oscillation frequency obtained for four sunspots show a feature shared by all the analysed levels of the solar atmosphere in these sunspots. This feature located in the inner penumbrae indicates that this region has favourable conditions for 2.5-4 mHz oscillation propagation. This agrees with the fact that the spectral composition of the oscillations at three atmospheric heights (FeI 6173{\\AA}, 1700{\\AA}, and He II 304{\\AA}) in this region are similar. There have been previous evidence of particular similarities along height of photospheric magnetic field strength, line-of-sight velocity, and temperature profile in the inner penumbra, where the internal boundary of the Evershed flow is located. The finding of the same dominant oscillation frequency at a range of altitudes from the chromosphere up to the transition region extends the height range, suggesting similarities in physical conditions.

  19. High-resolution proper motions in a sunspot penumbra

    CERN Document Server

    Márquez, I; Bonet, J A

    2006-01-01

    Local correlation tracking techniques are used to measure proper motions in a series of high angular resolution (~0.1 arcsec) penumbra images. If these motions trace true plasma motions, then we have detected converging flows that arrange the plasma in long narrow filaments co-spatial with dark penumbral filaments. Assuming that these flows are stationary, the vertical stratification of the atmosphere and the conservation of mass suggest downflows in the filaments of the order of 200 m/s. The association between downflows and dark features may be a sign of convection, as it happens with the non-magnetic granulation. Insufficient spatial resolution may explain why the estimated vertical velocities are not fast enough to supply the radiative losses of penumbrae.

  20. Population-based Stroke Atlas for outcome prediction: method and preliminary results for ischemic stroke from CT.

    Directory of Open Access Journals (Sweden)

    Wieslaw L Nowinski

    Full Text Available BACKGROUND AND PURPOSE: Knowledge of outcome prediction is important in stroke management. We propose a lesion size and location-driven method for stroke outcome prediction using a Population-based Stroke Atlas (PSA linking neurological parameters with neuroimaging in population. The PSA aggregates data from previously treated patients and applies them to currently treated patients. The PSA parameter distribution in the infarct region of a treated patient enables prediction. We introduce a method for PSA calculation, quantify its performance, and use it to illustrate ischemic stroke outcome prediction of modified Rankin Scale (mRS and Barthel Index (BI. METHODS: The preliminary PSA was constructed from 128 ischemic stroke cases calculated for 8 variants (various data aggregation schemes and 3 case selection variables (infarct volume, NIHSS at admission, and NIHSS at day 7, each in 4 ranges. Outcome prediction for 9 parameters (mRS at 7th, and mRS and BI at 30th, 90th, 180th, 360th day was studied using a leave-one-out approach, requiring 589,824 PSA maps to be analyzed. RESULTS: Outcomes predicted for different PSA variants are statistically equivalent, so the simplest and most efficient variant aiming at parameter averaging is employed. This variant allows the PSA to be pre-calculated before prediction. The PSA constrained by infarct volume and NIHSS reduces the average prediction error (absolute difference between the predicted and actual values by a fraction of 0.796; the use of 3 patient-specific variables further lowers it by 0.538. The PSA-based prediction error for mild and severe outcomes (mRS  =  [2]-[5] is (0.5-0.7. Prediction takes about 8 seconds. CONCLUSIONS: PSA-based prediction of individual and group mRS and BI scores over time is feasible, fast and simple, but its clinical usefulness requires further studies. The case selection operation improves PSA predictability. A multiplicity of PSAs can be computed independently for

  1. Formation and decay of rudimentary penumbra around a pore

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Hiroko [Unit of Synergetic Studies for Space, Kyoto University, Yamashina-ku, Kyoto 607-8417 (Japan); Kitai, Reizaburo [Kwasan and Hida Observatories, Kyoto University, Yamashina-ku, Kyoto 607-8417 (Japan); Otsuji, Kenichi, E-mail: watanabe@kwasan.kyoto-u.ac.jp [Solar Observatory, National Astronomical Observatory, Mitaka, Tokyo 181-8588 (Japan)

    2014-12-01

    We analyze the evolution of a pore in the active region NOAA 10940 using the data obtained by the Hinode satellite on 2007 February 3. The pore we analyzed showed the formation of a rudimentary penumbra structure, succeeded by an abrupt disappearance after about 5 hr. The pore had an approximate radius of 3.5 Mm and a total magnetic flux of 3.0 × 10{sup 19} Mx, which is a little smaller than the necessary magnetic flux for penumbral formation supposed by Rucklidge et al. (1-1.5 × 10{sup 20} Mx). Our observation describes a rare phenomenon which was in the unstable phase between a pore and a sunspot. The area of the dark umbra gradually decreased when the rudimentary penumbral filaments formed the penumbral structure, meaning that the penumbra develops at the expense of the umbral magnetic flux. This statement was confirmed by a rough estimation of the magnetic flux variation observed by the Hinode Fe I magnetogram. Five hours after the formation phase, the decay phase began. In this decaying phase, multiple opposite polarity patches are found to appear in the exterior of the pore (a different location from the penumbra formation site). We interpret these opposite polarities as signatures of the horizontal magnetic field, which preferably appears in the course of the unstable reconfiguration of the magnetic field structure. During the course of the disappearance of the penumbra, the horizontal penumbral field seems to become vertical because of the dark umbral area that recovered by about 10%.

  2. Microstructural changes in ischemic cortical gray matter predicted by a model of diffusion-weighted MRI

    DEFF Research Database (Denmark)

    Vestergaard-Poulsen, Peter; Hansen, Brian; Østergaard, Leif

    2007-01-01

    PURPOSE: To understand the diffusion attenuated MR signal from normal and ischemic brain tissue in order to extract structural and physiological information using mathematical modeling, taking into account the transverse relaxation rates in gray matter. MATERIALS AND METHODS: We fit our diffusion...... model to the diffusion-weighted MR signal obtained from cortical gray matter in healthy subjects. Our model includes variable volume fractions, intracellular restriction effects, and exchange between compartments in addition to individual diffusion coefficients and transverse relaxation rates for each...

  3. Population-based study of ABCD2 score, carotid stenosis, and atrial fibrillation for early stroke prediction after transient ischemic attack: the North Dublin TIA study.

    LENUS (Irish Health Repository)

    Sheehan, Orla C

    2010-05-01

    Transient ischemic attack (TIA) etiologic data and the ABCD(2) score may improve early stroke risk prediction, but studies are required in population-based cohorts. We investigated the external validity of the ABCD(2) score, carotid stenosis, and atrial fibrillation for prediction of early recurrent stroke after TIA.

  4. Deep probing of the photospheric sunspot penumbra: no evidence for magnetic field-free gaps

    CERN Document Server

    Borrero, J M; Collados, M; Schlichenmaier, R; Balthasar, H; Franz, M; Rezaei, R; Kiess, C; Suarez, D Orozco; Pastor, A; Berkefeld, T; von der Luehe, O; Schmidt, D; Schmidt, W; Sigwarth, M; Soltau, D; Volkmer, R; Waldmann, T; Denker, C; Hofmann, A; Staude, J; Strassmeier, K G; Feller, A; Lagg, A; Solanki, S K; Sobotka, M; Nicklas, H

    2016-01-01

    Some models for the topology of the magnetic field in sunspot penumbrae predict the existence of field-free or dynamically weak-field regions in the deep Photosphere. To confirm or rule out the existence of weak-field regions in the deepest photospheric layers of the penumbra. The magnetic field at $\\log\\tau_5=0$ is investigated by means of inversions of spectropolarimetric data of two different sunspots located very close to disk center with a spatial resolution of approximately 0.4-0.45 arcsec. The data have been recorded using the GRIS instrument attached to the 1.5-meters GREGOR solar telescope at El Teide observatory. It includes three Fe I lines around 1565 nm, whose sensitivity to the magnetic field peaks at half a pressure-scale-height deeper than the sensitivity of the widely used Fe I spectral line pair at 630 nm. Prior to the inversion, the data is corrected for the effects of scattered light using a deconvolution method with several point spread functions. At $\\log\\tau_5=0$ we find no evidence for...

  5. Deep probing of the photospheric sunspot penumbra: no evidence of field-free gaps

    Science.gov (United States)

    Borrero, J. M.; Asensio Ramos, A.; Collados, M.; Schlichenmaier, R.; Balthasar, H.; Franz, M.; Rezaei, R.; Kiess, C.; Orozco Suárez, D.; Pastor, A.; Berkefeld, T.; von der Lühe, O.; Schmidt, D.; Schmidt, W.; Sigwarth, M.; Soltau, D.; Volkmer, R.; Waldmann, T.; Denker, C.; Hofmann, A.; Staude, J.; Strassmeier, K. G.; Feller, A.; Lagg, A.; Solanki, S. K.; Sobotka, M.; Nicklas, H.

    2016-11-01

    Context. Some models for the topology of the magnetic field in sunspot penumbrae predict regions free of magnetic fields or with only dynamically weak fields in the deep photosphere. Aims: We aim to confirm or refute the existence of weak-field regions in the deepest photospheric layers of the penumbra. Methods: We investigated the magnetic field at log τ5 = 0 is by inverting spectropolarimetric data of two different sunspots located very close to disk center with a spatial resolution of approximately 0.4-0.45''. The data have been recorded using the GRIS instrument attached to the 1.5-m solar telescope GREGOR at the El Teide observatory. The data include three Fe i lines around 1565 nm, whose sensitivity to the magnetic field peaks half a pressure scale height deeper than the sensitivity of the widely used Fe i spectral line pair at 630 nm. Before the inversion, the data were corrected for the effects of scattered light using a deconvolution method with several point spread functions. Results: At log τ5 = 0 we find no evidence of regions with dynamically weak (Bdata, and does not depend on the amount of stray light (i.e., wide-angle scattered light) considered.

  6. Pediatric cerebral stroke: susceptibility-weighted imaging may predict post-ischemic malignant edema.

    Science.gov (United States)

    Bosemani, Thangamadhan; Poretti, Andrea; Orman, Gunes; Meoded, Avner; Huisman, Thierry A G M

    2013-10-01

    Susceptibility-weighted imaging (SWI) is an advanced MRI technique providing information on the blood oxygenation level. Deoxyhemoglobin is increased in hypoperfused tissue characterized by SWI-hypointensity, while high oxyhemoglobin concentration within hyperperfused tissue results in a SWI iso- or hyperintensity compared to healthy brain tissue. We describe a child with a stroke, where SWI in addition to excluding hemorrhage and delineating the thrombus proved invaluable in determining regions of hyperperfusion or luxury perfusion, which contributed further to the prognosis including an increased risk of developing post-ischemic malignant edema.

  7. The value of preoperative 3-dimensional over 2-dimensional valve analysis in predicting recurrent ischemic mitral regurgitation after mitral annuloplasty.

    Science.gov (United States)

    Wijdh-den Hamer, Inez J; Bouma, Wobbe; Lai, Eric K; Levack, Melissa M; Shang, Eric K; Pouch, Alison M; Eperjesi, Thomas J; Plappert, Theodore J; Yushkevich, Paul A; Hung, Judy; Mariani, Massimo A; Khabbaz, Kamal R; Gleason, Thomas G; Mahmood, Feroze; Acker, Michael A; Woo, Y Joseph; Cheung, Albert T; Gillespie, Matthew J; Jackson, Benjamin M; Gorman, Joseph H; Gorman, Robert C

    2016-09-01

    Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months. Intraoperative transesophageal 2-dimensional echocardiography and 3-dimensional echocardiography were performed in 50 patients undergoing undersized annuloplasty for ischemic mitral regurgitation. Two-dimensional echocardiography annular diameter and tethering parameters were measured in the apical 2- and 4-chamber views. A customized protocol was used to assess 3-dimensional annular geometry and regional leaflet tethering. Recurrence (grade ≥2) was assessed with 2-dimensional transthoracic echocardiography at 6 months. Preoperative 2- and 3-dimensional annular geometry were similar in all patients with ischemic mitral regurgitation. Preoperative 2- and 3-dimensional leaflet tethering were significantly higher in patients with recurrence (n = 13) when compared with patients without recurrence (n = 37). Multivariate logistic regression revealed preoperative 2-dimensional echocardiography posterior tethering angle as an independent predictor of recurrence with an optimal cutoff value of 32.0° (area under the curve, 0.81; 95% confidence interval, 0.68-0.95; P = .002) and preoperative 3-dimensional echocardiography P3 tethering angle as an independent predictor of recurrence with an optimal cutoff value of 29.9° (area under the curve, 0.92; 95% confidence interval, 0.84-1.00; P 3-dimensional geometric multivariate model can be augmented by adding basal aneurysm/dyskinesis (area under the curve, 0.94; 95% confidence interval, 0.87-1.00; P 3-dimensional echocardiography P3 tethering angle is a stronger predictor of ischemic mitral regurgitation recurrence after annuloplasty than preoperative 2-dimensional echocardiography posterior tethering angle, which is highly influenced by viewing plane. In

  8. Degree of Vascular Encasement in Sphenoid Wing Meningiomas Predicts Postoperative Ischemic Complications.

    Science.gov (United States)

    McCracken, D Jay; Higginbotham, Raymond A; Boulter, Jason H; Liu, Yuan; Wells, John A; Halani, Sameer H; Saindane, Amit M; Oyesiku, Nelson M; Barrow, Daniel L; Olson, Jeffrey J

    2017-06-01

    Sphenoid wing meningiomas (SWMs) can encase arteries of the circle of Willis, increasing their susceptibility to intraoperative vascular injury and severe ischemic complications. To demonstrate the effect of circumferential vascular encasement in SWM on postoperative ischemia. A retrospective review of 75 patients surgically treated for SWM from 2009 to 2015 was undertaken to determine the degree of circumferential vascular encasement (0°-360°) as assessed by preoperative magnetic resonance imaging (MRI). A novel grading system describing "maximum" and "total" arterial encasement scores was created. Postoperative MRIs were reviewed for total ischemia volume measured on sequential diffusion-weighted images. Of the 75 patients, 89.3% had some degree of vascular involvement with a median maximum encasement score of 3.0 (2.0-3.0) in the internal carotid artery (ICA), M1, M2, and A1 segments; 76% of patients had some degree of ischemia with median infarct volume of 3.75 cm 3 (0.81-9.3 cm 3 ). Univariate analysis determined risk factors associated with larger infarction volume, which were encasement of the supraclinoid ICA ( P 62 cm 3 was found when the ICA, M1, and A1 vessels all had ≥360° involvement ( P = .001). Residual tumor was associated with smaller infarct volumes ( P = .022). As infarction volume increased, so did modified Rankin Score at discharge ( P = .025). Subtotal resection should be considered in SWM with significant vascular encasement of proximal arteries to limit postoperative ischemic complications.

  9. Imaging acute ischemic stroke.

    Science.gov (United States)

    González, R Gilberto; Schwamm, Lee H

    2016-01-01

    Acute ischemic stroke is common and often treatable, but treatment requires reliable information on the state of the brain that may be provided by modern neuroimaging. Critical information includes: the presence of hemorrhage; the site of arterial occlusion; the size of the early infarct "core"; and the size of underperfused, potentially threatened brain parenchyma, commonly referred to as the "penumbra." In this chapter we review the major determinants of outcomes in ischemic stroke patients, and the clinical value of various advanced computed tomography and magnetic resonance imaging methods that may provide key physiologic information in these patients. The focus is on major strokes due to occlusions of large arteries of the anterior circulation, the most common cause of a severe stroke syndrome. The current evidence-based approach to imaging the acute stroke patient at the Massachusetts General Hospital is presented, which is applicable for all stroke types. We conclude with new information on time and stroke evolution that imaging has revealed, and how it may open the possibilities of treating many more patients. © 2016 Elsevier B.V. All rights reserved.

  10. Prediction of ischemic stroke in young Indians: is thrombophilia profiling a way out?

    Science.gov (United States)

    Chatterjee, Tathagata; Gupta, Neha; Choudhry, Ved Prakash; Behari, Madhuri; Saxena, Renu; Ashraf, Mohammad Z

    2013-06-01

    Stroke in the young is attributed to the prevalence of thrombophilia, however, reports explaining the cause mechanisms from Indian populations are largely not known. The information about the association of inherited thrombophilia and occurrence of stroke is still missing. Therefore, we describe here 52 cases of young ischemic stroke of which 22 cases were of recurrent stroke and 30 cases of first episode stroke along with an equal number of healthy controls. Imaging techniques (CT/MRI/Doppler studies) were used to identify the type and location of infarcts among various regions of the brain. All the patients and controls were screened for hypercoagulable state by employing Pro C global test. Those tested positive for the latter were evaluated for conventional thrombophilic factors, activity levels of protein C and protein S, antithrombin III levels, plasma homocysteine levels and presence of activated protein C resistance, lupus anticoagulant, methylenetetrahydrofolate reductase (MTHFR C677T) and prothrombin G20210A polymorphisms. Out of 52 cases there were 22 cases of recurrent stroke and 30 cases of first ischemic stroke. Infarcts were single in 39 out of 52 cases and multiple in 13 cases. Among the different regions of brain internal capsule infarcts were seen in 13 of 52 (25%) cases, and cerebellum, basal ganglion and midbrain infarcts were seen in five cases (9.6%) each and remaining infarcts were in other anatomical regions of the brain. Left middle cerebral artery territory was involved in 17 of 52 (32.7%) cases. The prevalence of individual thrombophilia among cases ranged from 28.8% (15/52) for protein S and 11.5% (6/52) for protein C deficiencies respectively. All cases of protein C were protein S deficient. Five cases of protein C deficiency patients were of 25 years and younger as compared with one case in the at least 25 years age group. Plasma homocysteine levels were elevated in three cases (5.7%) as compared with normal levels in controls

  11. Factors predicting ischemic-type biliary lesions (ITBLs) after liver transplantation.

    Science.gov (United States)

    Frongillo, F; Grossi, U; Avolio, A W; Sganga, G; Nure, E; Pepe, G; Bianco, G; Lirosi, M C; Agnes, S

    2012-09-01

    Among biliary complications, ischemic-type biliary lesions (ITBLs) remain a major cause of morbidity in liver transplant recipients, significantly affecting the chance of survival of both patients and grafts. We retrospectively reviewed 10 years of prospectively collected donor and recipient data from April 2001 to April 2011. We evaluated the incidence of ITBL occurrence, exploring the possible predisposing factors, including donor and recipient data. Two hundred fifty-one grafts were harvested: 222 of them were transplanted at our institution, the remaining 29 (11.6%) discarded by our donor team as showing >40% macrovesicular steatosis. Mild-moderate (20%-40%) macrovesicular steatosis (P < .001) and cold ischemia time (P = .048) significantly increased the risk of ITBL, also as an independent risk factor after multivariate analysis.

  12. Aortic Complex Plaque Predicts the Risk of Cryptogenic Ischemic Cerebrovascular Disease Recurrence.

    Science.gov (United States)

    Dong, Jing; Ma, Xin; Qie, Jingyuan; Ji, Xunming

    2016-03-01

    To evaluate the correlations between aortic complex plaque (ACP) and the recurrence of cryptogenic ischemic cerebrovascular disease (CICVD), and to investigate the clinical significance of ACP in CICVD. Methods CICVD patients (aged 17 to 84 years) admitted into the Department of Neurology, Xuanwu Hospital, from July 2011 to December 2013, were consecutively recruited, and divided into ACP and non-ACP groups according to head and neck computerized tomographic (CT) angiography. Recurrences of cerebral ischemic events (CIEs) were compared between these groups after follow-up. Results A total of 117 patients were enrolled (ACP group: 69, non-ACP group: 48) and followed up for a mean of 9.86 months (range: 3-33). The average age of the ACP group was 62.88 years, with 59.4% older than 60 years; the average age of the non-ACP group was 50.29 years, with 37.5% older than 60 years. At the 6-month follow-up, the recurrence rate of CIEs in the ACP group was significantly higher than that of the non-ACP group (17.0% [7/47] and 0% [0/36], respectively; χ2 = 4.283, P = 0.046). The cumulative recurrence risk for CIEs of the ACP group was significantly higher than for the non-ACP group (P = 0.004). Multivariate Cox survival analysis showed that ACP presence was an independent risk factor for CIE recurrence for CICVD patients (relative risk [RR] = 7.803, 95% confidence interval [CI], 1.827~33.319, P = 0.006). Conclusions ACP increased the recurrence risk of CIE in CICVD, and elderly CICVD patients should receive greater attention regarding the significance of ACP in recurrent CICVD.

  13. Predictive value of ischemic lesion volume assessed with magnetic resonance imaging for neurological deficits and functional outcome poststroke: A critical review of the literature.

    NARCIS (Netherlands)

    Schiemanck, S.K.; Kwakkel, G.; Post, M.W.; Prevo, A.J.

    2006-01-01

    OBJECTIVE: Ischemic lesion volume is assumed to be an important predictor of poststroke neurological deficits and functional outcome. This critical review examines the methodological quality of MRI studies and the predictive value of hemispheric infarct volume for neurological deficits (at body

  14. The Predictive Value of Waist-To-Height Ratio for Ischemic Stroke in a Population-Based Prospective Cohort Study among Mongolian Men in China

    Science.gov (United States)

    Xu, Juan; Xu, Tian; Bu, Xiaoqing; Peng, Hao; Li, Hongmei; Zhang, Mingzhi; Zhang, Yonghong

    2014-01-01

    Objective To explore the associations between waist-to-height ratio (WHtR), body mass index (BMI) and waist circumference (WC) and risk of ischemic stroke among Mongolian men in China. Methods A population-based prospective cohort study was conducted from June 2003 to July 2012 in Inner Mongolia, an autonomous region in north China. A total of 1034 men aged 20 years and older free of cardiovascular disease were included in the cohort and followed up for an average of 9.2 years. The subjects were divided into four groups by WHtR levels (WHtR0.60). The cumulative survival rates of ischemic stroke among the four groups were estimated with the Kaplan-Meier curves and compared by log-rank test. Cox proportional hazards models and Receiver Operating Characteristic (ROC) curves were employed to evaluate the associations between obesity indices and ischemic stroke. Results A total of 47 ischemic stroke patients were observed during the follow-up period. The cumulative incidence and incidence density of ischemic stroke were 4.55% and 507.61/100 000 person-years, respectively. After the major risk factors were adjusted, individuals with WHtR>0.60 had a 3.56-fold increased risk of ischemic stroke compared with those with 0.40≤WHtR≤0.50. Hazard ratio (HR) and 95% confidence intervals (CI) of ischemic stroke for a 1-SD increase in WHtR was 1.34(95% CI: 1.00–1.81). After adding BMI or WC to models, higher WHtR remained significantly associated with increased risk of ischemic stroke. The Kaplan-Meier survival curves showed that the cumulative survival rate in the group with WHtR>0.60 was significantly lower than in the group with 0.40≤WHtR≤0.50 (log-rank test, P = 0.025). The areas under the curve for each index were as follows: 0.586 for WHtR, 0.543 for WC; 0.566 for BMI. Conclusions Higher WHtR is associated with risk of ischemic stroke in Mongolian males. WHtR may be useful in predicting ischemic stroke incidence in males. PMID:25353632

  15. MRI blood-brain barrier permeability measurements to predict hemorrhagic transformation in a rat model of ischemic stroke.

    Science.gov (United States)

    Hoffmann, Angelika; Bredno, Jörg; Wendland, Michael F; Derugin, Nikita; Hom, Jason; Schuster, Tibor; Zimmer, Claus; Su, Hua; Ohara, Peter T; Young, William L; Wintermark, Max

    2012-12-01

    Permeability imaging might add valuable information in the risk assessment of hemorrhagic transformation. This study evaluates the predictive value of blood-brain barrier permeability (BBBP) measurements extracted from dynamic contrast-enhanced MRI for hemorrhagic transformation in ischemic stroke. Spontaneously hypertensive and Wistar rats with 2 h filament occlusion of the right MCA underwent MRI during occlusion, at 4 and 24 h post reperfusion. BBBP was imaged by DCE imaging and quantified by Patlak analysis. Cresyl-violet staining was used to characterize hemorrhage in sacrificed rats at 24 h, immediately following the last imaging study. BBBP changes were evaluated at baseline, 4 and 24 h after reperfusion. Receiver-operating characteristic (ROC) analysis was performed to determine the most accurate BBBP threshold to predict hemorrhagic transformation. In animals showing macroscopic hemorrhage at 24 h, 95th BBBP percentile values ipsilateral were 0.323 [0.260, 0.387], 0.685 [0.385, 0.985], and 0.412 [0.210, 0.613] ml/min·100 g (marginal mean [95%CI]) during occlusion, at 4 and 24 h post reperfusion, respectively. The BBBP values on the infarcted and contralateral side were significantly different at 4 (p = 0.034) and 24 h post reperfusion (p = 0.031). The predictive value of BBBP in terms of macroscopic hemorrhage was highest 4 h after reperfusion (ROC area under the curve = 84 %) with a high negative predictive value (98.3 %) and limited positive predictive value (14.9 %) for a threshold of 0.35 ml/min·100g. Altered BBBP is a necessary but not sufficient condition to cause hemorrhagic transformation in rats with an infarct. Further research is needed to identify those additional risk factors that are required for hemorrhagic transformation to develop in the setting of ischemic stroke.

  16. Evaluation of the penumbras of a Philips multileaf collimator

    Energy Technology Data Exchange (ETDEWEB)

    Lafay, F.; Malet, C.; Mombard, C.; Ginestet, C. [Centre de Lutte Contre le Cancer Leon-Berard, 69 - Lyon (France); Blondel, E. [Isotec, Saint-Quentin (France); Desfarges, Y.; Dupin, G. [Philips Medical System, Lyon (France)

    1995-12-01

    Since January 1995, a Philips SL20 linear accelerator which is connected to a multileaf collimator has been used. Computer-controlled multileaf collimators open up the opportunity to practice conformal radiotherapy. Its aim is to adjust as well as possible the Planning Target Volume (PTV) to the effective treated volume with an homogeneous dose distribution in the PTV, and to protect healthy tissues and delicate organs. This is possible by means of a multileaf collimator by increasing the number of complex fields with different incidences during a same session. Moreover, the Beam`s Eye View function of the three-dimensional treatment planning system allows to define the shape of complex fields. For rectangular fields, the penumbra is defined by the distance between the 80% and 20% isodoses relative to the beam axis. In addition, the distances between, respectively, the 95% and 50% isodoses, the 90% and 50% isodoses, the 50% and 20% isodoses relative to the beam axis have been analysed. Different penumbras were evaluated. The result of this work will enable to adjust the reference isodose to the PTV either by integrating this result into dosimetry software, or by taking it into account for drawing the PTV.

  17. Formation of a solar Ha filament from orphan penumbrae

    CERN Document Server

    Buehler, D; van Noort, M; Solanki, S K

    2016-01-01

    The formation of an Ha filament in active region (AR) 10953 is described. Observations from the Solar Optical Telescope (SOT) aboard the Hinode satellite starting on 27th April 2007 until 1st May 2007 were analysed. 20 scans of the 6302A Fe I line pair recorded by SOT/SP were inverted using the SPINOR code. The inversions were analysed together with SOT/BFI G-band and Ca II H and SOT/NFI Ha observations. Following the disappearance of an initial Ha filament aligned along the polarity inversion line (PIL) of the AR, a new Ha filament formed in its place some 20 hours later, which remained stable for at least 1.5 days. The creation of the new Ha filament was driven by the ascent of horizontal magnetic fields from the photosphere into the chromosphere at three separate locations along the PIL. The magnetic fields at two of these locations were situated directly underneath the initial Ha filament and formed orphan penumbrae already aligned along the Ha filament channel. The 700 G orphan penumbrae were stable and ...

  18. Relationship Between Collateral Status, Contrast Transit, and Contrast Density in Acute Ischemic Stroke.

    Science.gov (United States)

    Kawano, Hiroyuki; Bivard, Andrew; Lin, Longting; Spratt, Neil J; Miteff, Ferdinand; Parsons, Mark W; Levi, Christopher R

    2016-03-01

    Collateral circulation is recognized to influence the life expectancy of the ischemic penumbra in acute ischemic stroke. The best method to quantify collateral status on acute imaging is uncertain. We aimed to determine the relationship between visual collateral status, quantitative collateral assessments, baseline computed tomographic perfusion measures, and tissue outcomes on follow-up imaging. Sixty-six consecutive patients with acute ischemic stroke clinically eligible for recanalization therapy and with M1 or M2 middle cerebral artery occlusion were evaluated. We compared the visual collateral scoring with measures of contrast peak time delay and contrast peak density. We also compared these measures for their ability to predict perfusion lesion and infarct core volumes, final infarct, and infarct growth. Shorter contrast peak time delay (P=0.041) and higher contrast peak density (P=0.002) were associated with good collateral status. Shorter contrast peak time delay correlated with higher contrast peak density (β=-4.413; P=0.037). In logistic regression analysis after adjustment for age, sex, onset-computed tomographic time, and occlusion site, higher contrast peak density was independently associated with good collateral status (P=0.009). Multiple regression analysis showed that higher contrast peak density was an independent predictor of smaller perfusion lesion volume (P=0.029), smaller ischemic core volume (P=0.044), smaller follow-up infarct volume (P=0.005), and smaller infarct growth volume (P=0.010). Visual collateral status, contrast peak density, and contrast peak time delay were inter-related, and good collateral status was strongly associated with contrast peak density. Contrast peak density in collateral vessel may be an important factor in tissue fate in acute ischemic stroke. © 2016 American Heart Association, Inc.

  19. Risk-prediction model for ischemic stroke in patients hospitalized with an acute coronary syndrome (from the global registry of acute coronary events [GRACE]).

    Science.gov (United States)

    Park, Kay Lee; Budaj, Andrzej; Goldberg, Robert J; Anderson, Frederick A; Agnelli, Giancarlo; Kennelly, Brian M; Gurfinkel, Enrique P; Fitzgerald, Gordon; Gore, Joel M

    2012-09-01

    The risk of stroke in patients hospitalized with an acute coronary syndrome (ACS) ranges from ischemic stroke in patients with ACS to help guide clinicians in the acute management of these high-risk patients. Data were obtained from 63,118 patients enrolled from April 1999 to December 2007 in the Global Registry of Acute Coronary Events (GRACE), a multinational registry involving 126 hospitals in 14 countries. A regression model was developed to predict the occurrence of in-hospital ischemic stroke in patients hospitalized with an ACS. The main study outcome was the development of ischemic stroke during the index hospitalization for an ACS. Eight risk factors for stroke were identified: older age, atrial fibrillation on index electrocardiogram, positive initial cardiac biomarkers, presenting systolic blood pressure ≥ 160 mm Hg, ST-segment change on index electrocardiogram, no history of smoking, higher Killip class, and lower body weight (c-statistic 0.7). The addition of coronary artery bypass graft surgery and percutaneous coronary intervention into the model increased the prediction of stroke risk. In conclusion, the GRACE stroke risk score is a simple tool for predicting in-hospital ischemic stroke risk in patients admitted for the entire spectrum of ACS, which is widely applicable to patients in various hospital settings and will assist in the management of high-risk patients with ACS. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Predictive value of vertebral artery extracranial color-coded duplex sonography for ischemic stroke-related vertigo.

    Science.gov (United States)

    Liou, Li-Min; Lin, Hsiu-Fen; Huang, I-Fang; Chang, Yang-Pei; Lin, Ruey-Tay; Lai, Chiou-Lian

    2013-12-01

    Vertigo can be a major presentation of posterior circulation stroke and can be easily misdiagnosed because of its complicated presentation. We thus prospectively assessed the predictive value of vertebral artery extracranial color-coded duplex sonography (ECCS) for the prediction of ischemic stroke-related vertigo. The inclusion criteria were: (1) a sensation of whirling (vertigo); (2) intractable vertigo for more than 1 hour despite appropriate treatment; and (3) those who could complete cranial magnetic resonance imaging (MRI) and vertebral artery (V2 segment) ECCS studies. Eventually, 76 consecutive participants with vertigo were enrolled from Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung, Taiwan between August 2010 and August 2011. Demographic data, neurological symptoms, neurologic examinations, and V2 ECCS were assessed. We chose the parameters of peak systolic velocity (PSV), end diastolic velocity (EDV), PSV/EDV, mean velocity (MV), resistance index (RI), and pulsatility index (PI) to represent the hemodynamics. Values from both sides of V2 segments were averaged. We then calculated the average RI (aRI), average PI (aPI), average PSV (aPSV)/EDV, and average (aMV). Axial and coronal diffusion-weighted MRI findings determined the existence of acute ischemic stroke. We grouped and analyzed participants in two ways (way I and way II analyses) based on the diffusion-weighted MRI findings (to determine whether there was acute stroke) and neurological examinations. Using way I analysis, the "MRI (+)" group had significantly higher impedance (aRI, aPI, and aPSV/EDV ratio) and lower velocity (aPSV, aEDV, and aMV(PSV + EDV/2)), compared to the "MRI (-)" group. The cutoff value/sensitivity/specificity of aPSV, aEDV, aMV, aPI, aRI, and aPSV/EDV between the MRI (+) and MRI (-) groups were 41.15/61.5/66.0 (p = 0.0101), 14.55/69.2/72.0 (p = 0.0003), 29.10/92.1/38.0 (p = 0.0013), 1.07/76.9/64.0 (p = 0.0066), 0.62/76.9/64.0 (p = 0.0076), and 2.69/80.8/66.0 (p = 0

  1. Predictive value of vertebral artery extracranial color-coded duplex sonography for ischemic stroke-related vertigo

    Directory of Open Access Journals (Sweden)

    Li-Min Liou

    2013-12-01

    Full Text Available Vertigo can be a major presentation of posterior circulation stroke and can be easily misdiagnosed because of its complicated presentation. We thus prospectively assessed the predictive value of vertebral artery extracranial color-coded duplex sonography (ECCS for the prediction of ischemic stroke-related vertigo. The inclusion criteria were: (1 a sensation of whirling (vertigo; (2 intractable vertigo for more than 1 hour despite appropriate treatment; and (3 those who could complete cranial magnetic resonance imaging (MRI and vertebral artery (V2 segment ECCS studies. Eventually, 76 consecutive participants with vertigo were enrolled from Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung, Taiwan between August 2010 and August 2011. Demographic data, neurological symptoms, neurologic examinations, and V2 ECCS were assessed. We chose the parameters of peak systolic velocity (PSV, end diastolic velocity (EDV, PSV/EDV, mean velocity (MV, resistance index (RI, and pulsatility index (PI to represent the hemodynamics. Values from both sides of V2 segments were averaged. We then calculated the average RI (aRI, average PI (aPI, average PSV (aPSV/EDV, and average (aMV. Axial and coronal diffusion-weighted MRI findings determined the existence of acute ischemic stroke. We grouped and analyzed participants in two ways (way I and way II analyses based on the diffusion-weighted MRI findings (to determine whether there was acute stroke and neurological examinations. Using way I analysis, the “MRI (+” group had significantly higher impedance (aRI, aPI, and aPSV/EDV ratio and lower velocity (aPSV, aEDV, and aMV(PSV + EDV/2, compared to the “MRI (–” group. The cutoff value/sensitivity/specificity of aPSV, aEDV, aMV, aPI, aRI, and aPSV/EDV between the MRI (+ and MRI (– groups were 41.15/61.5/66.0 (p = 0.0101, 14.55/69.2/72.0 (p = 0.0003, 29.10/92.1/38.0 (p = 0.0013, 1.07/76.9/64.0 (p = 0.0066, 0.62/76.9/64.0 (p = 0.0076, and 2

  2. The "Penumbra Sign" on Magnetic Resonance Images of Brodie's Abscess: A Case Report.

    Science.gov (United States)

    Afshar, Ahmadreza; Mohammadi, Afshin

    2011-12-01

    This report presents the "penumbra sign" of a Brodie's abscess in a 69-year-old male patient. The lesion was located in the proximal metaphysis of the left tibia. Histopathology confirmed the diagnosis of subacute osteomyelitis. The penumbra sign on magnetic resonance (MR) images is a helpful sign for the diagnosis of Brodie's abscess.

  3. Rounded leaf end effect of multileaf collimator on penumbra width and radiation field offset: an analytical and numerical study

    Directory of Open Access Journals (Sweden)

    Zhou Dong

    2015-09-01

    Full Text Available Background. Penumbra characteristics play a significant role in dose delivery accuracy for radiation therapy. For treatment planning, penumbra width and radiation field offset strongly influence target dose conformity and organ at risk sparing.

  4. Persistent Penumbra in a Rabbit Stroke Model: Incidence and Histologic Characteristics

    Directory of Open Access Journals (Sweden)

    Leah J. Hennings

    2011-01-01

    Full Text Available Duration and extent of penumbra determine the window and brain volume in which interventions may save injured tissue after stroke. Understanding the penumbra in animals is necessary in order to design models that translate to effective clinical therapies. New Zealand white rabbits were embolized with aged autologous clot (n=23 or insoluble microspheres (n=21. To examine effects of treatment on penumbra, sphere-stroked animals were treated with 3 μm microbubbles plus ultrasound (n=19. Rabbits were euthanized at 4 or 24 hr. Infarct volume was measured following triphenyltetrazolium chloride (TTC staining of brain sections. Penumbra was visualized using immunostaining of pimonidazole injected fifteen minutes prior to euthanasia. Potentially reversible penumbra was present in 14.3% stroked rabbits at 4 hours and 15.7% at 24 hours after embolic stroke and represented up to 35% of total lost tissue. Intervention at up to 24 hours may benefit a significant patient population.

  5. Presenting Symptoms and Dysphagia Screen Predict Outcome in Mild and Rapidly Improving Acute Ischemic Stroke Patients.

    Science.gov (United States)

    Gadodia, Gaurav; Rizk, Nibal; Camp, Deborah; Bryant, Katja; Zimmerman, Susan; Brasher, Cynthia; Connelly, Kerrin; Dunn, Joshua; Frankel, Michael; Ido, Moges Seymour; Lugtu, James; Nahab, Fadi

    2016-12-01

    There are limited data on which patients not treated with intravenous (IV) tissue-type plasminogen activator (tPA) due to mild and rapidly improving stroke symptoms (MaRISS) have unfavorable outcomes. Acute ischemic stroke (AIS) patients not treated with IV tPA due to MaRISS from January 1, 2009 to December 31, 2013 were identified as part of the Georgia Coverdell Acute Stroke Registry. Multivariable regression analysis was used to identify factors associated with a lower likelihood of favorable outcome, defined as discharge to home. There were 1614 AIS patients who did not receive IV tPA due to MaRISS (median National Institutes of Health stroke scale [NIHSS] 1], of which 305 (19%) did not have a favorable outcome. Factors associated with lower likelihood of favorable outcome included Medicare insurance status (odds ratio [OR]: .53, 95% confidence interval [CI]: .34-.84), arrival by emergency medical services (OR: .46, 95% CI: .29-.73), increasing NIHSS score (per unit OR: .89, 95% CI: .84-.93), weakness as the presenting symptom (OR: .50, 95% CI: .30-.84), and a failed dysphagia screen (OR: .43, 95% CI: .23-.80). During the study period, dysphagia screen identify a subgroup of patients who are more likely to have an unfavorable outcome. Whether IV tPA treatment can improve the outcome in this subgroup of patients needs to be evaluated in a randomized placebo-controlled trial. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  6. Preoperative cerebrovascular reactivity to acetazolamide measured by brain perfusion SPECT predicts development of cerebral ischemic lesions caused by microemboli during carotid endarterectomy

    Energy Technology Data Exchange (ETDEWEB)

    Aso, Kenta; Ogasawara, Kuniaki; Kobayashi, Masakazu; Suga, Yasunori; Chida, Kohei; Otawara, Yasunari; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan)]|[Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Sasaki, Makoto [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan)

    2009-02-15

    The aim of the present study was to determine whether preoperative cerebrovascular reactivity (CVR) to acetazolamide measured by quantitative brain perfusion single-photon emission computed tomography (SPECT) predicts development of cerebral ischemic lesions on postoperative diffusion-weighted magnetic resonance imaging (DWI) that are caused by microemboli during carotid endarterectomy (CEA). One hundred and fifty patients with ipsilateral internal carotid artery stenosis (>70%) underwent CEA under transcranial Doppler monitoring of microembolic signals (MES) in the ipsilateral middle cerebral artery (MCA). Preoperative CVR to acetazolamide was measured using [{sup 123}I]N-isopropyl-p-iodoamphetamine SPECT, and region of interest (ROI) analysis in the ipsilateral MCA territory was performed using a three-dimensional stereotaxic ROI template. DWI was performed within 3 days before and 24 h after surgery. Twenty-six patients (17.3%) developed new postoperative ischemic lesions on DWI. Logistic regression analysis demonstrated that, among the variables tested, a high number of MES during carotid dissection (95% CIs, 1.179 to 1.486; P < 0.0001) and preoperative reduced CVR to acetazolamide (95% CIs, 0.902 to 0.974; P = 0.0008), which were significantly associated with the development of new postoperative ischemic lesions on DWI. In 47 patients with MES during carotid dissection, the combination of number of MES during carotid dissection and CVR to acetazolamide identified development of new postoperative ischemic lesions on DWI with a positive predictive value of 100% or zero. Preoperative CVR to acetazolamide measured by quantitative brain perfusion SPECT predicts development of cerebral ischemic lesions on postoperative DWI that are caused by microemboli during CEA. (orig.)

  7. Ischemic Stroke

    Science.gov (United States)

    A stroke is a medical emergency. There are two types - ischemic and hemorrhagic. Ischemic stroke is the most common type. It is usually ... are at risk for having a more serious stroke. Symptoms of stroke are Sudden numbness or weakness ...

  8. Convective motions and net circular polarization in sunspot penumbrae

    CERN Document Server

    Borrero, J M

    2009-01-01

    We have employed a penumbral model, that includes the Evershed flow and convective motions inside penumbral filaments, to reproduce the azimuthal variation of the net circular polarization (NCP) in sunspot penumbrae at different heliocentric angles for two different spectral lines. The theoretical net circular polarization fits the observations as satisfactorily as penumbral models based on flux-tubes. The reason for this is that the effect of convective motions on the NCP is very small compared to the effect of the Evershed flow. In addition, the NCP generated by convective upflows cancels out the NCP generated by the downflows. We have also found that, in order to fit the observed NCP, the strength of the magnetic field inside penumbral filaments must be very close to 1000 G. In particular, field-free or weak-field filaments fail to reproduce both the correct sign of the net circular polarization, as well as its dependence on the azimuthal and heliocentric angles.

  9. Machine learning for outcome prediction of acute ischemic stroke post intra-arterial therapy.

    Science.gov (United States)

    Asadi, Hamed; Dowling, Richard; Yan, Bernard; Mitchell, Peter

    2014-01-01

    Stroke is a major cause of death and disability. Accurately predicting stroke outcome from a set of predictive variables may identify high-risk patients and guide treatment approaches, leading to decreased morbidity. Logistic regression models allow for the identification and validation of predictive variables. However, advanced machine learning algorithms offer an alternative, in particular, for large-scale multi-institutional data, with the advantage of easily incorporating newly available data to improve prediction performance. Our aim was to design and compare different machine learning methods, capable of predicting the outcome of endovascular intervention in acute anterior circulation ischaemic stroke. We conducted a retrospective study of a prospectively collected database of acute ischaemic stroke treated by endovascular intervention. Using SPSS®, MATLAB®, and Rapidminer®, classical statistics as well as artificial neural network and support vector algorithms were applied to design a supervised machine capable of classifying these predictors into potential good and poor outcomes. These algorithms were trained, validated and tested using randomly divided data. We included 107 consecutive acute anterior circulation ischaemic stroke patients treated by endovascular technique. Sixty-six were male and the mean age of 65.3. All the available demographic, procedural and clinical factors were included into the models. The final confusion matrix of the neural network, demonstrated an overall congruency of ∼ 80% between the target and output classes, with favourable receiving operative characteristics. However, after optimisation, the support vector machine had a relatively better performance, with a root mean squared error of 2.064 (SD: ± 0.408). We showed promising accuracy of outcome prediction, using supervised machine learning algorithms, with potential for incorporation of larger multicenter datasets, likely further improving prediction. Finally, we

  10. Machine learning for outcome prediction of acute ischemic stroke post intra-arterial therapy.

    Directory of Open Access Journals (Sweden)

    Hamed Asadi

    Full Text Available INTRODUCTION: Stroke is a major cause of death and disability. Accurately predicting stroke outcome from a set of predictive variables may identify high-risk patients and guide treatment approaches, leading to decreased morbidity. Logistic regression models allow for the identification and validation of predictive variables. However, advanced machine learning algorithms offer an alternative, in particular, for large-scale multi-institutional data, with the advantage of easily incorporating newly available data to improve prediction performance. Our aim was to design and compare different machine learning methods, capable of predicting the outcome of endovascular intervention in acute anterior circulation ischaemic stroke. METHOD: We conducted a retrospective study of a prospectively collected database of acute ischaemic stroke treated by endovascular intervention. Using SPSS®, MATLAB®, and Rapidminer®, classical statistics as well as artificial neural network and support vector algorithms were applied to design a supervised machine capable of classifying these predictors into potential good and poor outcomes. These algorithms were trained, validated and tested using randomly divided data. RESULTS: We included 107 consecutive acute anterior circulation ischaemic stroke patients treated by endovascular technique. Sixty-six were male and the mean age of 65.3. All the available demographic, procedural and clinical factors were included into the models. The final confusion matrix of the neural network, demonstrated an overall congruency of ∼ 80% between the target and output classes, with favourable receiving operative characteristics. However, after optimisation, the support vector machine had a relatively better performance, with a root mean squared error of 2.064 (SD: ± 0.408. DISCUSSION: We showed promising accuracy of outcome prediction, using supervised machine learning algorithms, with potential for incorporation of larger multicenter

  11. Can Dental Pulp Calcification Predict the Risk of Ischemic Cardiovascular Disease?

    Directory of Open Access Journals (Sweden)

    Leila Khojastepour

    2013-01-01

    Full Text Available Objective: To report the association of pulp calcification with that of cardiovascular disease (CVD using digital panoramic dental radiographs.Materials and Methods: Digital panoramic radiographs of patients referred from the angiography department were included if the patient was under 55 years old and had non-restored or minimally restored molars and canines. An oral and maxillofacial radiologist evaluated the images for pulpal calcifications in the selected teeth. The sensitivity, specificity, positive predictive value and negative predictive value of panoramic radiography in predicting CVD were calculated.Results: Out of 122 patients who met the criteria, 68.2% of the patients with CVD had pulp chamber calcifications. Pulp calcification in panoramic radiography had a sensitivity of 68.9% to predict CVD.Conclusion: This study demonstrates that patients with CVD show an increased incidence of pulp calcification compared with healthy patients. The findings suggest that pulp calcification on panoramic radiography may have possibilities for use in CVD screening.

  12. Characteristics of Misclassified CT Perfusion Ischemic Core in Patients with Acute Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Ralph R E G Geuskens

    Full Text Available CT perfusion (CTP is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up.This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0. Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBV<2.0 ml/100g and infarct on follow-up noncontrast CT and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT regions. False discovery ratio (FDR, defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests.Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml; median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml. Median FDR between patients was 62% (IQR:49%-80%. Median relative mean transit time was 243% (IQR:198%-289% and 342% (IQR:249%-432% for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43-1.79 ml/100g (P<0.01 and 1.38 (IQR:1.15-1.49 ml/100g (P<0.01 for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly.For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly

  13. Modifications to the Patient Rule-Induction Method that utilize non-additive combinations of genetic and environmental effects to define partitions that predict ischemic heart disease

    DEFF Research Database (Denmark)

    Dyson, Greg; Frikke-Schmidt, Ruth; Nordestgaard, Børge G;

    2009-01-01

    This article extends the Patient Rule-Induction Method (PRIM) for modeling cumulative incidence of disease developed by Dyson et al. (Genet Epidemiol 31:515-527) to include the simultaneous consideration of non-additive combinations of predictor variables, a significance test of each combination...... that assesses the utility of genetic variants in predicting the presence of ischemic heart disease beyond the established risk factors....

  14. Doppler Ultrasonographic Parameters for Predicting Cerebral Vascular Reserve in Patients with Acute Ischemic Stroke

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Han Young; Lee, Hui Joong; Kim, Hye Jung; Kim, Yong Sun; Kang, Duk Sik [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2006-03-15

    We investigated Doppler ultrasonographic (US) parameters of patients with acute stroke to predict the cerebral vascular reserve (CVR) measured by SPECT. We reviewed the flow velocity and cross-sectional area of the circular vessel at the common, external, and internal carotid arteries (ICA) and the vertebral arteries (VA) in 109 acute stroke patients who underwent SPECT. Flow volume (FV) of each artery was calculated as the product of the angle-corrected time averaged flow velocity and cross-sectional area of the circular vessel. Total cerebral FV (TCBFV) was determined as the sum of the FVs of the right and left ICA and VA. We compared the Doppler US parameters between 44 cases of preserved and 65 cases of impaired CVR. In the preserved CVR group, ICA FV, anterior circulating FV (ACFV) and TCBFV were higher than in the impaired CVR group (p < 0.05, independent t-test). In the impaired CVR group, the ROC curves showed ACFV and TCBFV were suitable parameters to predict CVR (p < 0.05). Doppler US was helpful for understanding the hemodynamic state of acute stroke. FV measurement by Doppler US was useful for predicting CVR

  15. Neuropsychological and neuroimaging markers in prediction of cognitive impairment after ischemic stroke: a prospective follow-up study

    Science.gov (United States)

    Mehrabian, Shima; Raycheva, Margarita; Petrova, Neli; Janyan, Armina; Petrova, Mariya; Traykov, Latchezar

    2015-01-01

    Background There are few longitudinal studies with controversial results examining delayed changes in cognition after ischemic stroke and predictive values of neuropsychological and neuroimaging markers. Objective The objectives of this study were to evaluate the delayed changes in cognition in poststroke patients and their relationship to the neuropsychological and neuroimaging markers measured during the acute poststroke phase. Methods Eighty-five first-ever stroke inpatients (mean age 65.6±5.6 years) without previous cognitive complaints were prospectively evaluated with a comprehensive neuropsychological battery at the 5th day and the 1st, 6th, and 12th months. A wide range of clinical, radiological, and neuropsychological variables were examined. Results Our results showed significantly poorer performance on mini–mental state examination, memory, attention/executive functions, and processing speed in patients with stroke in comparison with stroke-free cognitively intact controls. Multiple regression analysis revealed that hippocampal atrophy is the strongest predictor of delayed cognitive impairment. Secondary divided subgroups according to Isaacs Set Test (IST) score showed that patients with IST score ≤28 had different patterns of cognitive and neurological impairment after 1 year. Baseline impairments in attention/executive functions and memory were associated with development of dementia in poststroke patients. Conclusion Executive functioning deficit appears to have a predictive power for cognitive impairment progression. The study suggests that IST as a screening test has a potential to be a reliable and quick tool for poststroke cognitive impairment evaluation and delayed cognitive and neurological outcome. Hippocampal atrophy was the strongest predictor for cognitive impairment outcome, even in poststroke cognitive impairment. The findings may set the stage for better poststroke management. PMID:26527875

  16. A lower baseline glomerular filtration rate predicts high mortality and newly cerebrovascular accidents in acute ischemic stroke patients.

    Science.gov (United States)

    Dong, Kai; Huang, Xiaoqin; Zhang, Qian; Yu, Zhipeng; Ding, Jianping; Song, Haiqing

    2017-02-01

    Chronic kidney disease (CKD) is gradually recognized as an independent risk factor for cardiovascular and cardio-/cerebrovascular disease. This study aimed to examine the association of the estimated glomerular filtration rate (eGFR) and clinical outcomes at 3 months after the onset of ischemic stroke in a hospitalized Chinese population.Totally, 972 patients with acute ischemic stroke were enrolled into this study. Modified of Diet in Renal Disease (MDRD) equations were used to calculate eGFR and define CKD. The site and degree of the stenosis were examined. Patients were followed-up for 3 months. Endpoint events included all-cause death and newly ischemic events. The multivariate logistic model was used to determine the association between renal dysfunction and patients' outcomes.Of all patients, 130 patients (13.4%) had reduced eGFR (stroke patients. A low baseline eGFR was also a strong independent predictor for newly ischemic events in ICAS patients.

  17. Penumbra Stroke System as an "add-on" for the treatment of large vessel occlusive disease following thrombolysis: first results.

    Science.gov (United States)

    Struffert, Tobias; Köhrmann, Martin; Engelhorn, Tobias; Nowe, Tim; Richter, Gregor; Schellinger, Peter D; Schwab, Stefan; Doerfler, Arnd

    2009-09-01

    The Penumbra Stroke System (PSS) was cleared for use in patients with ischemic stroke by the FDA in January 2008. We describe our experience of using this new system in acute large vessel occlusive disease following thrombolysis. Fifteen consecutive patients (mean age 60 years) suffering from acute ischemic stroke were treated with the PSS after intravenous or intra-arterial standard treatment with tissue plasminogen activator (n = 14) or ReoPro (n = 1). All patients presented with TIMI 3 before use of the PSS. Carotid stenting (n = 3) and intracranial balloon angioplasty or stenting (n = 2) were performed if indicated. Neurological evaluation was performed using the NIHSS score and the mRS score. Initial median NIHSS score in 12 patients with occlusions in the anterior circulation was 15; three patients with basilar artery occlusion presented with coma. Median symptom to procedure start time was 151 min. In the anterior circulation, 9 of the 12 target vessels were recanalised successfully (TIMI 2 and 3). The rate of patients with independent clinical outcome (mRS ischemic stroke due to large vessel occlusion, who have already received thrombolysis treatment. The recanalisation rate was 80%. Symptomatic haemorrhage did not occur. Randomized trials may demonstrate that endovascular mechanical thrombectomy improves patient outcome.

  18. Fasting triglycerides predict recurrent ischemic events in patients with acute coronary syndrome treated with statins.

    Science.gov (United States)

    Schwartz, Gregory G; Abt, Markus; Bao, Weihang; DeMicco, David; Kallend, David; Miller, Michael; Mundl, Hardi; Olsson, Anders G

    2015-06-02

    Most patients with acute coronary syndrome (ACS) are treated with statins, which reduce atherogenic triglyceride-rich lipoproteins. It is uncertain whether triglycerides predict risk after ACS on a background of statin treatment. This study examined the relationship of fasting triglyceride levels to outcomes after ACS in patients treated with statins. Long-term and short-term relationships of triglycerides to risk after ACS were examined in the dal-OUTCOMES trial and atorvastatin arm of the MIRACL (Myocardial Ischemia Reduction with Acute Cholesterol Lowering) trial, respectively. Analysis of dal-OUTCOMES included 15,817 patients (97% statin-treated) randomly assigned 4 to 12 weeks after ACS to treatment with dalcetrapib (a cholesteryl ester transfer protein inhibitor) or placebo and followed for a median 31 months. Analysis of MIRACL included 1,501 patients treated with atorvastatin 80 mg daily beginning 1 to 4 days after ACS and followed for 16 weeks. Fasting triglycerides at initial random assignment were related to risk of coronary heart disease death, nonfatal myocardial infarction, stroke, and unstable angina in models adjusted for age, sex, hypertension, smoking, diabetes, high-density lipoprotein cholesterol, and body mass index. Fasting triglyceride levels were associated with both long-term and short-term risk after ACS. In dal-OUTCOMES, long-term risk increased across quintiles of baseline triglycerides (p175/≤80 mg/dl) was 1.61 (95% confidence interval: 1.34 to 1.94). There was no interaction of triglycerides and treatment assignment on the primary outcome. In the atorvastatin group of MIRACL, short-term risk increased across tertiles of baseline triglycerides (p=0.03), with a hazard ratio of 1.50 [corrected] (95% confidence interval: 1.05 to 2.15) in highest/lowest tertiles (>195/≤135 mg/dl). The relationship of triglycerides to risk was independent of low-density lipoprotein cholesterol in both studies. Among patients with ACS treated effectively

  19. Acute antithrombotic treatment of ischemic stroke.

    Science.gov (United States)

    Alderazi, Yazan J; Grotta, James C

    2014-05-01

    Antithrombotic medication is a cornerstone of acute ischemic stroke treatment and secondary prevention. The efficacy of thrombolysis with alteplase in acute stroke has been demonstrated in several clinical trials. This safe and costeffective therapy has transformed the practice of stroke care and has led to subsequent trials of other antithrombotic medications for treatment of ischemic stroke in the acute phase. These antithrombotics include thrombolytic, antiplatelet and anticoagulant agents. While, no other medication has yet demonstrated adequate efficacy, our current and evolving understanding of infarct expansion, ischemic penumbra, collateral circulation and the blood brain barrier is allowing testing of antithrombotic medications tailored to individual patient pathophysiology in clinical trials. This understanding accompanies developments in neuroimaging and organization of stroke care that allow for wide-spread recruitment in these trials. Alteplase remains the mainstay treatment of arterial acute ischemic stroke; however, anticoagulation is the standard therapy for cerebral venous sinus thrombosis. Antithrombotic use in acute stroke, arterial and venous, has demonstrated efficacy but leaves many questions unanswered. This patient population is a fertile ground for novel research, especially as it relates to; combination antithrombotic therapy, combination of pharmacological and mechanical thrombolysis, and the transition to secondary prevention. Here we review the current antithrombotics in the acute phase of ischemic stroke highlighting the evidence-base and areas of uncertainty.

  20. Shadow Segmentation and Augmentation Using á-overlay Models that Account for Penumbra

    DEFF Research Database (Denmark)

    Nielsen, Michael; Madsen, Claus B.

    2006-01-01

    that an augmented virtual object can cast an exact shadow. The penumbras (half-shadows) must be taken into account so that we can model the soft shadows.We hope to achieve this by modelling the shadow regions (umbra and penumbra alike) with a transparent overlay. This paper reviews the state-of-the-art shadow...... theories and presents two overlay models. These are analyzed analytically in relation to color theory and tangibility....

  1. Twist, Writhe & Helicity in the inner penumbra of a sunspot

    CERN Document Server

    Cobo, Basilio Ruiz

    2011-01-01

    The aim of this work is the determination of the twist, writhe, and self magnetic helicity of penumbral filaments located in an inner Sunspot penumbra. To this extent, we inverted data taken with the spectropolarimeter (SP) aboard {\\it Hinode} with the SIR (Stokes Inversion based on Response function) code. For the construction of a 3D geometrical model we applied a genetic algorithm minimizing the divergence of $\\vec{B}$ and the net magnetohydrodynamic force, consequently a force-free solution would be reached if possible. We estimated two proxies to the magnetic helicity frequently used in literature: the force-free parameter $\\alpha_z$ and the current helicity term $h_{c_{z}}$. We show that both proxies are only qualitative indicators of the local twist as the magnetic field in the area under study significantly departures from a force-free configuration. The local twist shows significant values only at the borders of bright penumbral filaments with opposite signs on each side. These locations are precisel...

  2. CTA collateral score predicts infarct volume and clinical outcome after endovascular therapy for acute ischemic stroke: a retrospective chart review.

    Science.gov (United States)

    Elijovich, Lucas; Goyal, Nitin; Mainali, Shraddha; Hoit, Dan; Arthur, Adam S; Whitehead, Matthew; Choudhri, Asim F

    2016-06-01

    Acute ischemic stroke (AIS) due to emergent large-vessel occlusion (ELVO) has a poor prognosis. To examine the hypothesis that a better collateral score on pretreatment CT angiography (CTA) would correlate with a smaller final infarct volume and a more favorable clinical outcome after endovascular therapy (EVT). A retrospective chart review of the University of Tennessee AIS database from February 2011 to February 2013 was conducted. All patients with CTA-proven LVO treated with EVT were included. Recanalization after EVT was defined by Thrombolysis in Cerebral Infarction (TICI) score ≥2. Favorable outcome was assessed as a modified Rankin Score ≤3. Fifty patients with ELVO were studied. The mean National Institutes of Health Stroke Scale score was 17 (2-27) and 38 of the patients (76%) received intravenous tissue plasminogen activator. The recanalization rate for EVT was 86.6%. Good clinical outcome was achieved in 32% of patients. Univariate predictors of good outcome included good collateral scores (CS) on presenting CTA (p=0.043) and successful recanalization (p=0.02). Multivariate analysis confirmed both good CS (p=0.024) and successful recanalization (p=0.009) as predictors of favorable outcome. Applying results of the multivariate analysis to our cohort we were able to determine the likelihood of good clinical outcome as well as predictors of smaller final infarct volume after successful recanalization. Good CS predict smaller infarct volumes and better clinical outcome in patients recanalized with EVT. These data support the use of this technique in selecting patients for EVT. Poor CS should be considered as an exclusion criterion for EVT as patients with poor CS have poor clinical outcomes despite recanalization. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Neuropsychological and neuroimaging markers in prediction of cognitive impairment after ischemic stroke: a prospective follow-up study

    Directory of Open Access Journals (Sweden)

    Mehrabian S

    2015-10-01

    Full Text Available Shima Mehrabian,1 Margarita Raycheva,1 Neli Petrova,2 Armina Janyan,3,4 Mariya Petrova,1 Latchezar Traykov1 1Clinic of Neurology, University Hospital Alexandrovska, Sofia, 2Clinic of Neurology, MHAT “Ruse”, Ruse, 3Research Center for Cognitive Science, Department of Cognitive Science and Psychology, New Bulgarian University, Sofia, Bulgaria; 4Laboratory for Cognitive Studies in Language, National Research Tomsk State University, Tomsk, Russia Background: There are few longitudinal studies with controversial results examining delayed changes in cognition after ischemic stroke and predictive values of neuropsychological and neuroimaging markers. Objective: The objectives of this study were to evaluate the delayed changes in cognition in poststroke patients and their relationship to the neuropsychological and neuroimaging markers measured during the acute poststroke phase. Methods: Eighty-five first-ever stroke inpatients (mean age 65.6±5.6 years without previous cognitive complaints were prospectively evaluated with a comprehensive neuropsychological battery at the 5th day and the 1st, 6th, and 12th months. A wide range of clinical, radiological, and neuropsychological variables were examined. Results: Our results showed significantly poorer performance on mini–mental state examination, memory, attention/executive functions, and processing speed in patients with stroke in comparison with stroke-free cognitively intact controls. Multiple regression analysis revealed that hippocampal atrophy is the strongest predictor of delayed cognitive impairment. Secondary divided subgroups according to Isaacs Set Test (IST score showed that patients with IST score ≤28 had different patterns of cognitive and neurological impairment after 1 year. Baseline impairments in attention/executive functions and memory were associated with development of dementia in poststroke patients. Conclusion: Executive functioning deficit appears to have a predictive power

  4. Blood-Brain Barrier Permeability Assessed by Perfusion CT Predicts Symptomatic Hemorrhagic Transformation and Malignant Edema in Acute Ischemic Stroke

    NARCIS (Netherlands)

    Hom, J.; Dankbaar, J. W.; Soares, B. P.; Schneider, T.; Cheng, S. -C.; Bredno, J.; Lau, B. C.; Smith, W.; Dillon, W. P.; Wintermark, M.

    BACKGROUND AND PURPOSE: SHT and ME are feared complications in patients with acute ischemic stroke. They occur >10 times more frequently in tPA-treated versus placebo-treated patients. Our goal was to evaluate the sensitivity and specificity of admission BBBP measurements derived from PCT in

  5. Prediction of clinical outcome with baseline and 24-hour perfusion CT in acute middle cerebral artery territory ischemic stroke treated with intravenous recanalization therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji-Yong; Kim, Seo Hyun; Park, Sang Hyun; Lee, Sung Soo [Yonsei University Wonju College of Medicine, Department of Neurology, Wonju (Korea); Lee, Myeong Sub [Yonsei University Wonju College of Medicine, Department of Radiology, Wonju (Korea)

    2008-05-15

    We sought to determine whether Alberta Stroke Program Early CT Scores (ASPECTS) derived from baseline noncontrast CT (NCCT) and perfusion CT (CTP) imaging maps can predict clinical outcome after recanalization therapy in acute ischemic stroke of the middle cerebral artery (MCA) territory and whether changes in the ASPECTS from baseline to 24 h after recanalization therapy can help predict clinical outcome. We retrospectively studied consecutive patients with acute ischemic stroke of the MCA territory treated with intravenous tissue plasminogen activator (t-PA) or abciximab within 6 h of symptom onset. We performed NCCT and CTP before and 24 h after intravenous t-PA or abciximab treatment and determined the ASPECTS and the changes in the ASPECTS from baseline to 24 h. A favorable outcome was defined as a modified Rankin scale score of 0 or 1 at 3 months. During the 18-month study period 44 patients were studied. In multivariate logistic regression analysis, the cerebral blood volume (CBV) ASPECTS (OR 1.80, 95% CI 1.10 to 2.93) at baseline and the increase in cerebral blood flow (CBF) ASPECTS (OR 1.68, 95% CI 1.13 to 2.50) from baseline to 24 h were associated with a favorable outcome. The cutoff values for a favorable outcome using receiver operating characteristic curves were 8 and 1, respectively. When the CBV ASPECTS at baseline was 8 or more, its positive predictive value was only 58.1%. When the CBV ASPECTS at baseline was 8 or more and the increase in CBF ASPECTS from baseline to 24 h was 1 or more, the positive predictive value was 100% and the negative predictive value was 74.2%. The CBV ASPECTS derived from baseline CTP maps was found to be predictive of a favorable outcome, but its positive predictive value was suboptimal. The change in the CBF ASPECTS from baseline to 24 h after treatment was helpful in predicting outcome. (orig.)

  6. Predictive factors for spasticity among ischemic stroke patients Fatores preditivos para espasticidade após acidente vascular cerebral

    Directory of Open Access Journals (Sweden)

    Rita de Cássia dos Reis Moura

    2009-12-01

    Full Text Available Spasticity is a determining for functional loss following ischemic stroke. OBJECTIVE: To detect possible predictive factors for its occurrence. METHOD: Demographic, clinical and tomographic data on 146 stroke patients were analyzed. RESULTS: Spasticity was noted more frequently among patients who underwent physiotherapy (pA espasticidade é fator determinante para perda funcional após o acidente vascular cerebral isquêmico (AVCI. OBJETIVO: Detectar possíveis fatores preditivos para a ocorrência da espasticidade. MÉTODO: Foram analisados dados demográficos, clínicos e tomográficos de 146 pacientes pós-AVCI. RESULTADOS: Na análise univariada a espasticidade foi notada com maior freqüência em pacientes que realizaram fisioterapia (p<0,0001; OR=19,4; 95% CI: 4,4-84,5, com maior tempo de duração desse tratamento (p=0,028; OR=4,80; 95% CI: 1,1-8,3 e que realizavam trabalho braçal (p=0,041; OR=2,2; 95% CI: 1,02-4,6, renda menor (p=0,038, referência de dor (p<0,0001; OR=107,0; 95% CI: 13,5-847,3 e seu aparecimento simultâneo à espasticidade (p<0,0001, acidente vascular cerebral (AVC pregresso (p=0,001; OR=4,2; 95% CI: 1,7-10,3, fraqueza muscular (p<0,0001; OR=91,9; 95% CI: 12,0-699,4, lesão tomográfica extensa (p=0,01 e lesão afetando mais de um lobo cerebral (p=0,018. Na análise de regressão multivariada a atividade braçal apresentou risco relativo de 2,9; acidente vascular cerebral prévio com risco relativo de 3,9 e lesão tomográfica extensa risco relativo de 3,6. CONCLUSÃO: A espasticidade afetou um quarto da população estudada e esteve associada ao trabalho braçal, AVC pregresso, lesões tomográficas extensas, diminuição da renda individual, realização de fisioterapia, realização de fisioterapia por um período maior, presença de dor, surgimento da dor simultânea à espasticidade e alteração da força.

  7. Short-Term Prognosis of Transient Ischemic Attack and Predictive Value of the ABCD2 Score in Hong Kong Chinese

    Directory of Open Access Journals (Sweden)

    Lai Hong Simon Chiu

    2014-03-01

    Full Text Available Background: Literature on prognosis of transient ischemic attack (TIA in Chinese is scarce. The short-term prognosis of TIA and the predictive value of the ABCD2 score in Hong Kong Chinese patients attending the emergency department (ED were studied to provide reference for TIA patient management in our ED. Methods: A cohort of TIA patients admitted through the ED to 13 acute public hospitals in 2006 was recruited through the centralized electronic database by the Hong Kong Hospital Authority (HA. All inpatients were e-coded by the HA according to the International Classification of Diseases, Ninth Revision (ICD9. Electronic records and hard copies were studied up to 90 days after a TIA. The stroke risk of a separate TIA cohort diagnosed by the ED was compared. Results: In the 1,000 recruited patients, the stroke risk after a TIA at days 2, 7, 30, and 90 was 0.2, 1.4, 2.9, and 4.4%, respectively. Antiplatelet agents were prescribed in 89%, warfarin in 6.9%, statin in 28.6%, antihypertensives in 39.3%, and antidiabetics in 11.9% of patients after hospitalization. Before the index TIA, the prescribed medications were 27.6, 3.7, 11.3, 27.1, and 9.7%, respectively. The accuracy of the ABCD2 score in predicting stroke risk was 0.607 at 7 days, 0.607 at 30 days, and 0.574 at 90 days. At 30 days, the p for trend across ABCD2 score levels was 0.038 (OR for every score point = 1.36, p = 0.040. Diabetes mellitus, previous stroke and carotid bruit were associated with stroke within 90 days (p = 0.038, 0.045, 0.030, respectively. A total of 45.4% of CTs of the brain showed lacunar infarcts or small vessel disease. There was an increased stroke risk at 90 days in patients with old or new infarcts on CT or MRI. Patients with carotid stenosis ≥70% had an increased stroke risk within 30 (OR = 6.335, p = 0.013 and 90 days (OR = 3.623, p = 0.050. Stroke risks at days 2, 7, 30, and 90 in the 289 TIA patients diagnosed by the ED were 0.35, 2.4, 5.2, and 6

  8. The Fine-Structure of the Net-Circular Polarization in a Sunspot Penumbra

    CERN Document Server

    Tritschler, A; Schlichenmaier, R; Hagenaar, H J

    2007-01-01

    We present novel evidence for a fine structure observed in the net-circular polarization (NCP) of a sunspot penumbra based on spectropolarimetric measurements utilizing the Zeeman sensitive FeI 630.2 nm line. For the first time we detect a filamentary organized fine structure of the NCP on spatial scales that are similar to the inhomogeneities found in the penumbral flow field. We also observe an additional property of the visible NCP, a zero-crossing of the NCP in the outer parts of the center-side penumbra, which has not been recognized before. In order to interprete the observations we solve the radiative transfer equations for polarized light in a model penumbra with embedded magnetic flux tubes. We demonstrate that the observed zero-crossing of the NCP can be explained by an increased magnetic field strength inside magnetic flux tubes in the outer penumbra combined with a decreased magnetic field strength in the background field. Our results strongly support the concept of the uncombed penumbra.

  9. Penumbra characteristics of square photon beams delimited by a GEMS multi-leaf collimator

    Energy Technology Data Exchange (ETDEWEB)

    Briot, E.; Julia, F. [Centre de Lutte Contre le Cancer Gustave-Roussy, 94 - Villejuif (France)

    1995-12-01

    A multi-leaf collimator (MLC) has been designed to replace directly the standard collimator of a SATURNE IV Series linac. It consists of 2 x 32 tungsten leaves and one set of upper block jaws. Isodose curves and dose profiles were measured for symmetric fields at the depth of the maximum and the reference depths for 6 MV, 10 MV, 18 MV photon beams. The penumbra (80%-20%) corresponding to the face and the side of the leaves have been compared with the standard collimators. Along with the X direction, the field delimitation is performed primarily with the leaves which are continuously variable in position. Along the Y direction, the field is initially approximated by the closure of opposite leaf pairs; then the Y upper jaws produce the exact size of the required field. As the leaves move linearly the penumbra (80%-20%) corresponding to the leaf ends is minimized and held constant at all positions by curvature of their faces. Penumbra obtained with the superposition of leaves and Y jaws depend on their relative position. The penumbra is minimum when the leaf side and the Y jaw edge coincide and the comparison of the measurement values with the conventional collimator shows that the differences are within 1 mm. When the leaves delineating the field are not entirely covered by the Y block upper jaws, the penumbra increases, and the junction of the opposing leaves, a width increase up to 3.5 mm has been measured.

  10. A technique to sharpen the beam penumbra for Gamma Knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, M; Li, X Allen; Ma Lijun [Department of Radiation Oncology, University of Maryland, School of Medicine, Baltimore, MD 21201 (United States)

    2003-06-21

    In stereotactic radiosurgery, a narrow beam penumbra is often desired for producing steep dose fall-off between the target volume and adjacent critical structures. Due to limited source sizes and the scattering effects, the physical penumbra of the Gamma Knife (GK) is often restricted to a width of 1-2 mm. In this work, we developed a technique to further reduce the beam penumbra and improve the dose profile for the Gamma Knife delivery. Under this technique, a conic filter is inserted into an individual plug collimator of a GK helmet to flatten the beam profile. Monte Carlo calculations were carried out to simulate the GK geometry of the individual plug collimator and to optimize the physical shapes of the filters. The calculations were performed for a series of filter shapes with different collimator sizes. Our results show that a proper filter significantly reduces the single GK beam penumbra width (defined as the distance from the 90% to 50% isodose lines) by 30-60%. The beam intensity is reduced by about 20-50% when the filter is used. A treatment plan was developed for a trigeminal neuralgia case by commissioning the filtered beam profile for Leksell Gamma Plan (version 5.31). Compared with the conventional treatment plan, a significant improvement was found on the critical structure sparing and on the target dose uniformity. In conclusion, the proposed technique is feasible and effective in sharpening the beam penumbra for Gamma Knife beam profiles.

  11. PTEN degradation after ischemic stroke: a double-edged sword.

    Science.gov (United States)

    Li, W; Huang, R; Chen, Z; Yan, L-J; Simpkins, J W; Yang, S-H

    2014-08-22

    Tumor suppressor phosphatase and tensin homolog (PTEN) is highly expressed in neurons and PTEN inhibition has been reported to be neuroprotective against ischemic stroke in experimental models. On the other hand, PTEN deletion has been shown to lead to cognitive impairment. In the current study, we examined the expression and functions of PTEN in an ischemic stroke rodent model. We found rapid S-nitrosylation and degradation of PTEN after cerebral ischemia/reperfusion injury. PTEN degradation leads to activation of Akt. PTEN partial deletion or PTEN inhibition increased the expression of GABAA receptor (GABAAR) γ2 subunit and enhanced GABAA receptor current. After cerebral ischemia, increased expression of GABAAR γ2 subunit was observed in the ischemia region and the penumbra area. We also observed PTEN loss in astrocytes after cerebral ischemia. Astrocytic PTEN partial knockout increased astrocyte activation and exacerbated ischemic damage. We speculated that ischemic stroke induced neuronal PTEN degradation, hence enhanced GABAA receptor-medicated neuronal activity inhibition which could attenuate excitotoxicity and provide neuroprotection during the acute phase after stroke, while inhibiting long-term functional recovery and contributing to vascular cognitive impairment after stroke. On the other hand, ischemic stroke induced astrocytic PTEN loss and enhanced ischemic damage and astrogliosis. Taken together, our study indicates that ischemic stroke induces rapid PTEN degradation in both neurons and astrocytes which play both protective and detrimental action in a spatiotemporal- and cell-type-dependent manner. Our study provides critical insight for targeting PTEN signaling pathway for stroke treatment.

  12. Cerebral Microbleeds Do Not Predict Hemorrhagic Transformation in Acute Ischemic Stroke Patients with Atrial Fibrillation and/or Rheumatic Heart Disease.

    Science.gov (United States)

    Liu, Junfeng; Wang, Deren; Li, Jie; Lin, Jing; Xiong, Yao; Liu, Bian; Wei, Chenchen; Wu, Bo; Ma, Zhenxing; Zhang, Shihong; Liu, Ming

    2017-01-01

    Cerebral microbleeds (CMBs) are known to be potential risk factors for intracerebral hemorrhage (ICH), but there is controversy on the relationship between CMBs and hemorrhagic transformation (HT) after ischemic stroke. Besides, the question regarding whether the relationship between CMBs and HT can be affected by antithrombotic drugs in acute stage of ischemic stroke has not yet reached a consensus. 174 acute ischemic stroke patients with atrial fibrillation (AF) and/or rheumatic heart disease (RHD) were prospectively and consecutively enrolled in the study, of which 160 patients (mean 68.09 ±12.59 years) were finally included in the final analysis (West China Hospital, Sichuan University, n=125; People's Hospital of Deyang City, n=35).We assessed the presence, location and number of CMBs by using susceptibility-weighted imaging (SWI) within 7 days after admission, and the incidence of hemorrhagic transformation was evaluated by magnetic resonance imaging(MRI) during hospitalization. The univariate and multivariate analyses were used to analyze the relationship between CMBs and HT. CMBs were detected in 90 patients (56.3%). HT was found in 62 (38.8%) patients, among which 43 were hemorrhagic infarction (HI) and 19 were parenchymal haemorrhage (PH). The presence of CMBs was not significantly different among different HT subtypes (no HT, HI and PH; 59.2%, 51.2%, versus 52.6%, P=0.64). There was no relationship between the number/location of CMBs and hemorrhagic transformation subtypes (P=0.38). In the 2 subgroups of patients treated with anticoagulants and antiplatelets after admission, the incidence of HT was not significantly different between patients with and without CMBs (anticoagulants, 13.3% versus 18.2%, P=0.71; antiplatelets, 29.2% versus 40.3%, P= 0.21). The present study suggests that CMBs do not predict the presence of hemorrhagic transformation in acute ischemic stroke patients with AF and/or RHD. The results were not affected by anticoagulant or

  13. Apoptosis and Acute Brain Ischemia in Ischemic Stroke.

    Science.gov (United States)

    Radak, Djordje; Katsiki, Niki; Resanovic, Ivana; Jovanovic, Aleksandra; Sudar-Milovanovic, Emina; Zafirovic, Sonja; Mousad, Shaker A; Isenovic, Esma R

    2017-01-01

    Apoptosis may contribute to a significant proportion of neuron death following acute brain ischemia (ABI), but the underlying mechanisms are still not fully understood. Brain ischemia may lead to stroke, which is one of the main causes of long-term morbidity and mortality in both developed and developing countries. Therefore, stroke prevention and treatment is clinically important. There are two important separate areas of the brain during ABI: the ischemic core and the ischemic penumbra. The ischemic core of the brain experiences a sudden reduction of blood flow, just minutes after ischemic attack with irreversible injury and subsequent cell death. On the other hand, apoptosis within the ischemic penumbra may occur after several hours or days, while necrosis starts in the first hours after the onset of ABI in the ischemic core. ABI is characterized by key molecular events that initiate apoptosis in many cells, such as overproduction of free radicals, Ca2+ overload and excitotoxicity. These changes in cellular homeostasis may trigger either necrosis or apoptosis, which often depends on cell type, cell age, and location in the brain. Apoptosis results in DNA fragmentation, degradation of cytoskeletal and nuclear proteins, cross-linking of proteins, formation of apoptotic bodies, expression of ligands for phagocytic cell receptors and finally uptake by phagocytic cells. This review focuses on recent findings based on animal and human studies regarding the apoptotic mechanisms of neuronal death following ABI and the development of potential neuroprotective agents that reduce morbidity. The effects of statins on stroke prevention and treatment as well as on apoptotic mediators are also considered. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. The predictive value of thyroid hormone levels on the neurological outcomes of patients with acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Guo-dong CHEN

    2015-03-01

    Full Text Available Objective To explore the correlation between thyroid hormone levels in patients with acute ischemic stroke and the severity of disease and short-term prognosis. Methods According to the level of serum total triiodothyronine (TT3, 98 patients who presented first acute ischemic stroke and without history of thyroid abnormality were divided into low TT3 group and normal TT3 group. Thyroid hormone levels and neurological function defect of those patients were tested, and their neural functional recovery after 3 months was evaluated.  Results Low TT3 group had more severe neural function defect compared to normal TT3 group (χ2 = 58.134, P = 0.000. There were no significant differences on total thyroxine (TT4; t = 1.636, P = 0.105 and thyroid stimulating hormone (TSH; t = 1.059, P = 0.292 between 2 groups. There was a significantly negative correlation between TT3 levels and National Insititute of Health Stroke Scale (NIHSS score on admission (r = -0.672, P = 0.000. Patients with low TT3 showed a significantly smaller percentage of neurological function improvement on both NIHSS ( χ2 = 8.993, P = 0.003 and modified Rankin Scale (mRS; χ2 = 6.247, P = 0.012 scores compared to those with normal TT3 at 90 d after onset.  Conclusions Low T3 level is associated with the severity of acute ischemic stroke and neural functional recovery, suggesting serum T3 level may be a predictor of neural function improvement in patients with acute ischemic stroke. DOI: 10.3969/j.issn.1672-6731.2015.02.009

  15. Thrombolysis with intravenous tissue plasminogen activator predicts a favorable discharge disposition in patients with acute ischemic stroke.

    Science.gov (United States)

    Ifejika-Jones, Nneka L; Harun, Nusrat; Mohammed-Rajput, Nareesa A; Noser, Elizabeth A; Grotta, James C

    2011-03-01

    Acute ischemic stroke patients who receive recombinant tissue plasminogen activator (rt-PA) within 3 hours of symptom onset are 30% more likely to have minimal to no disability at 3 months. During hospitalization, short-term disability is subjectively measured by discharge disposition, whether to home, inpatient rehabilitation, a skilled nursing facility, or subacute care. There are no studies assessing the role of recombinant tissue plasminogen activator use as a predictor of poststroke discharge disposition. We conducted a retrospective analysis of all patients with ischemic stroke who presented within the original three hour window for intravenous thrombolysis, and who were admitted to the University of Texas Houston Medical School Stroke Service at Memorial Hermann Hospital - Texas Medical Center between January 2004 and October 2009. Baseline demographics and National Institute of Health Stroke Scale score were collected. Cerebrovascular disease risk factors were used for risk stratification in the multivariate regression. Out of 2225 patients with acute ischemic stroke, 1019 were discharged to home, 719 to inpatient rehabilitation, 371 to a skilled nursing facility and 116 to subacute care. Patients who received recombinant tissue plasminogen activator therapy were more likely to be discharged home compared to the other levels of care (Pacute inpatient rehabilitation versus skilled nursing facility/subacute care and disposition at a skilled nursing facility versus subacute care, there were no differences in disposition between patients who received recombinant tissue plasminogen activator therapy. Inpatient Rehabilitation versus Skilled Nursing Facility or Subacute Care (P = 0.123); Skilled Nursing Facility versus Subacute Care (P = 0.605). Patients who receive intravenous recombinant tissue plasminogen activator as treatment for acute ischemic stroke are more likely to be discharged directly home after hospitalization. This study is limited by its

  16. β-FIBRINOGEN PROMOTER-455 G/A (HaeⅢ) POLYMORPHISM PREDICTION OF PLASMA FIBRINOGEN BUT NOT OF ISCHEMIC CEREBROVASCULAR DISEASE

    Institute of Scientific and Technical Information of China (English)

    毕胜; 王德生; 李国忠; 温世荣; 潘尚哈

    2004-01-01

    Objective The-455 G/A (HaeⅢ) polymorphism of β-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of ischemic cerebrovascular disease. Methods We accumulated 134 acute ischemic cerebrovascular disease (ICVD) cases and compared their -455 G/A status with a control group (n = 166). The β-fibrinogen gene -455 G/A polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme HaeⅢ. Results Plasma fibrinogen was higher in AA homozygous participants (341 mg/dL) than in participants carrying the G allele: GA (290 mg/dL), GG (298 mg/dL) in the control group. Plasma fibrinogen was also higher in AA homozygous patients (353 mg/dL) than in cases carrying the G allele: GA (287mg/dL), GG (302 mg/dL) in the ICVD group. However, there was no significant association between β-fibrinogen gene -455 G/A polymorphism and ICVD group. Conclusions Although a small effect cannot be excluded, β-fibrinogen gene -455 G/A polymorphism is an independent predictor of plasma fibrinogen, but not of ischemic cerebrovascular disease.

  17. RAPID PENUMBRA AND LORENTZ FORCE CHANGES IN AN X1.0 SOLAR FLARE

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhe; Jiang, Yunchun; Yang, Jiayang; Yang, Bo; Bi, Yi, E-mail: xuzhe6249@ynao.ac.cn [Yunnan Observatories, Chinese Academy of Sciences, P.O. Box 110, Kunming 650011 (China)

    2016-03-20

    We present observations of the violent changes in photospheric magnetic structures associated with an X1.1 flare, which occurred in a compact δ-configuration region in the following part of AR 11890 on 2013 November 8. In both central and peripheral penumbra regions of the small δ sunspot, these changes took place abruptly and permanently in the reverse direction during the flare: the inner/outer penumbra darkened/disappeared, where the magnetic fields became more horizontal/vertical. Particularly, the Lorentz force (LF) changes in the central/peripheral region had a downward/upward and inward direction, meaning that the local pressure from the upper atmosphere was enhanced/released. It indicates that the LF changes might be responsible for the penumbra changes. These observations can be well explained as the photospheric response to the coronal field reconstruction within the framework of the magnetic implosion theory and the back reaction model of flares.

  18. Is there more valuable information in PWI datasets for a voxel-wise acute ischemic stroke tissue outcome prediction than what is represented by typical perfusion maps?

    Science.gov (United States)

    Forkert, Nils Daniel; Siemonsen, Susanne; Dalski, Michael; Verleger, Tobias; Kemmling, Andre; Fiehler, Jens

    2014-03-01

    The acute ischemic stroke is a leading cause for death and disability in the industry nations. In case of a present acute ischemic stroke, the prediction of the future tissue outcome is of high interest for the clinicians as it can be used to support therapy decision making. Within this context, it has already been shown that the voxel-wise multi-parametric tissue outcome prediction leads to more promising results compared to single channel perfusion map thresholding. Most previously published multi-parametric predictions employ information from perfusion maps derived from perfusion-weighted MRI together with other image sequences such as diffusion-weighted MRI. However, it remains unclear if the typically calculated perfusion maps used for this purpose really include all valuable information from the PWI dataset for an optimal tissue outcome prediction. To investigate this problem in more detail, two different methods to predict tissue outcome using a k-nearest-neighbor approach were developed in this work and evaluated based on 18 datasets of acute stroke patients with known tissue outcome. The first method integrates apparent diffusion coefficient and perfusion parameter (Tmax, MTT, CBV, CBF) information for the voxel-wise prediction, while the second method employs also apparent diffusion coefficient information but the complete perfusion information in terms of the voxel-wise residue functions instead of the perfusion parameter maps for the voxel-wise prediction. Overall, the comparison of the results of the two prediction methods for the 18 patients using a leave-one-out cross validation revealed no considerable differences. Quantitatively, the parameter-based prediction of tissue outcome led to a mean Dice coefficient of 0.474, while the prediction using the residue functions led to a mean Dice coefficient of 0.461. Thus, it may be concluded from the results of this study that the perfusion parameter maps typically derived from PWI datasets include all

  19. Electroencephalogram and magnetic resonance imaging comparison as a predicting factor for neurodevelopmental outcome in hypoxic ischemic encephalopathy infant treated with hypothermia

    Directory of Open Access Journals (Sweden)

    Francesca Del Balzo

    2014-10-01

    Full Text Available Hypoxic-ischemic encephalopathy (HIE is an important cause of acute neurological damage in newborns at (or near term. Several trials in recent years have shown that moderate hypothermia by total body cooling or selective head is an effective intervention to reduce mortality and major disability in infants survived a perinatal hypoxic-ischemic attack. Follow-up in these patients is very important to establish neurodevelopmental outcome, and specific markers can lead us to detect predicting sign for good or poor outcome. We reported a few cases of newborn with HIE treated with hypothermia, in whom the comparison between electroencephalogram (EEG and magnetic resonance imaging (MRI represents the first marker for neurodevelopment outcome prediction. The continuous EEG monitoring showed a depressed EEG activity with diffuse burst depression in 7 patients. No epileptic abnormalities were registered. In 10 out of 20 patients no abnormalities of the background activity and no epileptic abnormalities were observed. We found that a depressed EEG activity during the first 72 h of life and a diffused alteration of basal ganglia at MRI were correlated with a poor neurodevelopmental outcome at 18 months of follow-up.

  20. RESCUING THE ISCHEMIC PENUMBRA—OUR EXPIRIENCE

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    Milosavljevic Tamara

    2013-12-01

    Full Text Available Objectives: Over one million strokes per year are occurring in Europe. Brain stroke is one of the most important death and disability causes in Europe and USA. The main role of perfusion is to determine the border of insult core and ischemic penumbra. Penumbra can be saved with thrombolytic therapy but core have irreversible injuries and represent death of brain cells. Aim: to determine the role of CT brain perfusion in cases of acute brain stroke and following thrombolytic therapy. Methods: We examined 64 patients with acute brain stroke who received thrombolytic therapy after that. All patients were examining on 16 MDCTwith 50 ml of iodine contrast agent following the standard procedure for CT perfusion. Patients were 34 male and 30 female with middle age of 64 years. MRI was made after thrombolytic therapy and compare with perfusion results before therapy. Results: Using an artery and a vein as reference three parameters were measured — blood flow (CBF, blood volume (CBV and mean transit time (MTT, for each patient. Hemorrhagic was find in 9 (14.01% patients after thrombolytic therapy. 4 (6.25% other patients develop new stroke of same but mostly other side of brain. 8 (12.50% more patients finished lethally. From other 42 patientswith thrombolytic therapywe can positively say that in 31 (48.44% patients penumbrawas rescued. For other 11 (17.19% stroke was same size like firstly involved core and penumbra but not bigger. Conclusion: CT perfusion plays major role by showing a curable parts of tissue in brain strokes

  1. Computed tomography perfusion imaging may predict cognitive impairment in patients with first-time anterior circulation transient ischemic attack.

    Science.gov (United States)

    Wang, Jun; Li, Yunming; Zheng, Bo; Wang, Jian; Wang, Zhiqiang; Duan, Dan; Li, Yuxia; Wang, Qingsong

    2016-04-01

    To determine whether computed tomography perfusion imaging (CTPI)-derived parameters are associated with vascular cognitive impairment (VCI) in patients with transient ischemic attack (TIA). Patients with first-time anterior circulation TIA (diagnosed within 24 h of onset) and normal cognition, treated between August 2009 and August 2014 at the Department of Neurology of Chengdu Military General Hospital, China, were analyzed retrospectively. Patients underwent whole-brain CTPI within 1 week of TIA to detect cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) in the ischemic region. Based on cognitive function assessment 4 weeks after TIA, using the Montreal cognitive assessment (MoCA) and mini mental state examination, the patients were divided into control and VCI groups. CTPI parameters and other clinical data were compared between groups, and Spearman's correlation analysis used to identify associations between cognitive scores and CTPI parameters in the VCI group. 50 patients (25 per group; aged 55-72 years) were included. Patient age, gender, smoking status, alcohol consumption, educational level, time from TIA onset to admission, time from TIA onset to CTPI, and prevalence of hypertension, diabetes mellitus, hyperlipidemia, atrial fibrillation and hyperhomocysteinemia did not differ between groups. Both groups showed TTP and MTT prolongation, CBF reduction, but no change in CBV in the ischemic region; these changes were significantly larger in the VCI group (P < 0.05). MTT correlated negatively with MoCA score (r = -0.51, P = 0.009). CTPI could facilitate early diagnosis of VCI in patients with anterior circulation TIA.

  2. Ischemic preconditioning

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    Ristić-Anđelkov Anđelka

    2005-01-01

    Full Text Available Background. Ischemic preconditioning is a phenomenon during which myocardium, subjected to brief episodes of ischemia followed by reperfusion, tolerates better the subsequent, more prolonged episode of this ischemia, thus reducing the infarction size substantially. Case report. Two patients with acute left anterior descendent artery occlusion received fibrinolytic therapy (alteplase within 6 hours of the onset of chest pain, but developed myocardial infarctions of different sizes. The first patient, without the history of preinfarction angina, developed large anterior infarct, because there was no time either for ischemic preconditioning or for the coronary collateral vessels development. In the second patient, with 4-day history of preinfarction angina, the more favorable outcome was seen he developed smaller apical necrosis, with the great degree of myocardial viability in the infarct-related area. Conclusion. Ischemic preconditioning in patients with acute myocardal infarction results in the reduction of mortality, infarction size, as well as in the frequency of malignant arrhythmias.

  3. Prediction models of stroke risk after transient ischemic attack%短暂性脑缺血发作后卒中风险预测模型

    Institute of Scientific and Technical Information of China (English)

    陈培; 裴璐璐; 许予明; 宋波

    2015-01-01

    The risk of stroke increases significantly after transient ischemic attack (TIA). TIA is an independent risk factor for cerebral infarction. This article review s the advances in prediction models of stroke risk after TIA in order to conduct rapid and accurate risk assessment and stratification in patients w ith TIA and develop timely reasonable treatment strategies, thereby reducing the risk of stroke.%短暂性脑缺血发作(transient ischemic attack,TIA)后卒中风险显著增高,是脑梗死的独立危险因素。文章就 TIA 后卒中风险预测模型的新进展进行了综述,以便对 TIA 患者进行快速准确的风险评估及分层,进而制定及时合理的治疗策略,从而降低卒中风险。

  4. Long-term survival and regeneration of neuronal and vasculature cells inside the core region after ischemic stroke in adult mice.

    Science.gov (United States)

    Jiang, Michael Qize; Zhao, Ying-Ying; Cao, Wenyuan; Wei, Zheng Zachory; Gu, Xiaohuan; Wei, Ling; Yu, Shan Ping

    2016-08-11

    Focal cerebral ischemia results in an ischemic core surrounded by the peri-infarct region (penumbra). Most research attention has been focused on penumbra while the pattern of cell fates inside the ischemic core is poorly defined. In the present investigation, we tested the hypothesis that, inside the ischemic core, some neuronal and vascular cells could survive the initial ischemic insult while regenerative niches might exist many days after stroke in the adult brain. Adult mice were subjected to focal cerebral ischemia induced by permanent occlusion of distal branches of the middle cerebral artery (MCA) plus transient ligations of bilateral common carotid artery (CCA). The ischemic insult uniformly reduced the local cerebral blood flow (LCBF) by 90%. Massive cell death occurred due to multiple mechanisms and a significant infarction was cultivated in the ischemic cortex 24 h later. Nevertheless, normal or even higher levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) persistently remained in the core tissue, some NeuN-positive and Glut-1/College IV-positive cells with intact ultrastructural features resided in the core 7-14 days post stroke. BrdU-positive but TUNEL-negative neuronal and endothelial cells were detected in the core where extensive extracellular matrix infrastructure developed. Meanwhile, GFAP-positive astrocytes accumulated in the penumbra and Iba-1-positive microglial/macrophages invaded the core several days after stroke. The long term survival of neuronal and vascular cells inside the ischemic core was also seen after a severe ischemic stroke induced by permanent embolic occlusion of the MCA. We demonstrate that a therapeutic intervention of pharmacological hypothermia could save neurons/endothelial cells inside the core. These data suggest that the ischemic core is an actively regulated brain region with residual and newly formed viable neuronal and vascular cells acutely and chronically after at

  5. On the velocity field of sunspot penumbrae - I. A global view

    CERN Document Server

    Franz, Morten

    2009-01-01

    We investigated the vertical penumbral plasma flow on small spatial scales using data recorded by the spectropolarimeter of the solar optical telescope onboard Hinode. To this end we computed maps of apparent Doppler velocities by comparing the spectral position of the Fe I 630.15 nm & Fe I 630.25 nm lines with the averaged line profiles of the quiet Sun. To visualize the flow pattern in the low photosphere, we used a bisector of the wing of the absorption lines. Due to the small heliocentric angle (3 0.6 km/s down-flows prevail. Additionally, the maximal up-flow velocity in penumbrae is smaller, while the maximal down-flow velocity is larger with respect to the QS velocities. Furthermore, on a spatial average, the penumbra shows a red-shift, corresponding to a down-flow of more than 0.1 km/s. Up-flows are elongated and appear predominately in the inner penumbra. Strong down-flows with velocities of up to 9 km/s are concentrated at the penumbra-QS boundary. They are magnetized and are rather round in sha...

  6. Clinical study on HAT and SEDAN score scales and related risk factors for predicting hemorrhagic transformation following thrombolysis in acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Heng WEI

    2015-03-01

    Full Text Available Objective To investigate the value of HAT and SEDAN score scales in predicting hemorrhagic transformation (HT following the recombinant tissue-type plasminogen activator (rt-PA intravenous thrombolysis in acute ischemic stroke patients and risk factors affecting HT.  Methods A total of 143 patients with acute ischemic stroke underwent rt-PA intravenous thrombolysis within 4.50 h of onset and their clinical data were collected. According to head CT after thrombolysis, patients were divided into HT group (18 cases and non-HT group (125 cases. Single factor analysis was used to assess differences in HAT and SEDAN score scales and related risk factors of ischemic stroke in 2 groups, and further Logistic regression analysis was used to investigate independent predictors of HT. Receiver operating characteristic (ROC curve was used to evaluate the sensitivity and specificity of HAT and SEDAN score scales in predicting HT.  Results Univariate Logistic regression analysis showed that history of atrial fibrillation (AF, admission systolic blood pressure (SBP, admission blood glucose level, early low density of head CT, thrombolytic time window, National Institute of Health Stroke Scale (NIHSS, HAT and SEDAN scores were all risk factors for HT after thrombolysis (P < 0.05, for all. Multivariate Logistic regression analysis showed that history of AF (OR = 1.677, 95% CI: 1.332-2.111; P = 0.000, admission SBP (OR = 1.102, 95% CI: 1.009-1.204; P = 0.031, admission blood glucose level (OR = 1.870, 95% CI: 1.119-3.125; P = 0.017, thrombolysis time window (OR = 1.030, 95%CI: 1.009-1.052; P = 0.005, NIHSS score (OR = 1.574, 95%CI: 1.186-2.090; P = 0.002, HAT score (OR = 2.515, 95%CI: 1.273-4.970;P = 0.008 and SEDAN score (OR = 2.413, 95%CI: 1.123-5.185; P = 0.024 were risk factors for HT after thrombolysis. ROC curve analysis showed that HAT score could predict HT with 94.40% sensitivity and 41.60% specificity, and area under curve (AUC was 0.70. SEDAN

  7. Observed and predicted reduction of ischemic cardiovascular events in the Simvastatin and Ezetimibe in Aortic Stenosis trial

    DEFF Research Database (Denmark)

    Holme, Ingar; Boman, Kurt; Brudi, Philippe

    2010-01-01

    In the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) trial, combined ezetimibe (10 mg) and simvastatin (40 mg) decreased low-density lipoprotein cholesterol levels by 50% and ischemic cardiovascular event (ICE) risk by 22% compared to placebo. A larger decrease in ICE risk might have been...... expected for the degree of lipid-lowering observed. This analysis investigated relations between changes in lipoprotein components (LCs), and ICE risk decrease in the SEAS trial in all patients, by severity of aortic stenosis (AS), and compared to results of other clinical trials. A total of 1,570 patients...... with baseline aortic jet velocity (JV) data, baseline and 1-year low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and apolipoprotein B, and no ICEs during the first year were included in the analysis. Relations between on-treatment measurements of 1-year LCs and time-to-ICE occurrence...

  8. Scanning laser polarimetry, but not optical coherence tomography predicts permanent visual field loss in acute nonarteritic anterior ischemic optic neuropathy.

    Science.gov (United States)

    Kupersmith, Mark J; Anderson, Susan; Durbin, Mary; Kardon, Randy

    2013-08-15

    Scanning laser polarimetry (SLP) reveals abnormal retardance of birefringence in locations of the edematous peripapillary retinal nerve fiber layer (RNFL), which appear thickened by optical coherence tomography (OCT), in nonarteritic anterior ischemic optic neuropathy (NAION). We hypothesize initial sector SLP RNFL abnormalities will correlate with long-term regional visual field loss due to ischemic injury. We prospectively performed automated perimetry, SLP, and high definition OCT (HD-OCT) of the RNFL in 25 eyes with acute NAION. We grouped visual field threshold and RNFL values into Garway-Heath inferior/superior disc sectors and corresponding superior/inferior field regions. We compared sector SLP RNFL thickness with corresponding visual field values at presentation and at >3 months. At presentation, 12 eyes had superior sector SLP reduction, 11 of which had inferior field loss. Six eyes, all with superior field loss, had inferior sector SLP reduction. No eyes had reduced OCT-derived RNFL acutely. Eyes with abnormal field regions had corresponding SLP sectors thinner (P = 0.003) than for sectors with normal field regions. During the acute phase, the SLP-derived sector correlated with presentation (r = 0.59, P = 0.02) and with >3-month after presentation (r = 0.44, P = 0.02) corresponding superior and inferior field thresholds. Abnormal RNFL birefringence occurs in sectors corresponding to regional visual field loss during acute NAION when OCT-derived RNFL shows thickening. Since the visual field deficits show no significant recovery, SLP can be an early marker for axonal injury, which may be used to assess recovery potential at RNFL locations with respect to new treatments for acute NAION.

  9. Real-time myocardial contrast echocardiography can predict functional recovery and left ventricular remodeling after revascularization in patients with ischemic heart disease

    Institute of Scientific and Technical Information of China (English)

    ZENG Xin; SHU Xian-hong; PAN Cui-zhen; LI Qing; GUO Shi-zun; LIU Shi-zhen; CHEN Hao-zhu

    2007-01-01

    Background Previous studies showed that preservation of microvascular integrity after myocardial ischemia was associated with myocardial viability. Real-time myocardial contrast echocardiography (RT-MCE) is a promising modality for non-invasive evaluation of microcirculation perfusion. Thus, it provides a unique tool to detect myocardial viability. We sought in this study to investigate the role of RT-MCE in predicting left ventricular (LV) functional recovery and remodeling after revascularization in patients with ischemic heart disease.Methods Thirty-one patients with ischemic heart disease and resting regional LV dysfunction were included. LV volume,global and regional function were evaluated by echocardiography before and 6-9 months after revascularization.RT-MCE was performed before revascularization using low mechanical index power modulation imaging. Myocardial contrast opacification of dysfunctional segments was scored on a 3-point scale and mean contrast score in dysfunctional segments was calculated. Patients were divided into 2 groups according to mean contrast score in dysfunctional segments: group A, patients with mean contrast score ≥0.5 (n=19); group B, patients with mean contrast score < 0.5(n=12).Results Wall motion improvement was found to be 94.5%, 45.5% and 16.1% respectively (P<0.01) in homogenous,patchy and absent contrast opacification segments. At baseline, there was no significant difference in LV volume and global function between the two groups. After revascularization, group B had significantly larger LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV), lower LV ejection fraction (LVEF) and higher wall motion score index(WMSI) than those of group A (all P<0.05). Revascularization was followed by significant improvement of LV volume and recovery of global LV function in group A (all P<0.01); however, in group B, after revascularization, deterioration of LVEDV (P<0.05) was observed, moreover LVESV, WMSI and LVEF

  10. Multimodal nanoprobes evaluating physiological pore size of brain vasculatures in ischemic stroke models.

    Science.gov (United States)

    Zheng, Shuyan; Bai, Ying-Ying; Changyi, Yinzhi; Gao, Xihui; Zhang, Wenqing; Wang, Yuancheng; Zhou, Lu; Ju, Shenghong; Li, Cong

    2014-11-01

    Ischemic stroke accounts for 80% strokes and originates from a reduction of cerebral blood flow (CBF) after vascular occlusion. For treatment, the first action is to restore CBF by thrombolytic agent recombinant tissue-type plasminogen activator (rt-PA). Although rt-PA benefits clinical outcome, its application is limited by short therapeutic time window and risk of brain hemorrhage. Different to thrombolytic agents, neuroprotectants reduce neurological injuries by blocking ischemic cascade events such as excitotoxicity and oxidative stress. Nano-neuroprotectants demonstrate higher therapeutic effect than small molecular analogues due to their prolonged circulation lifetime and disrupted blood-brain barrier (BBB) in ischemic region. Even enhanced BBB permeability in ischemic territories is verified, the pore size of ischemic vasculatures determining how large and how efficient the therapeutics can pass is barely studied. In this work, nanoprobes (NPs) with different diameters are developed. In vivo multimodal imaging indicates that NP uptakes in ischemic region depended on their diameters and the pore size upper limit of ischemic vasculatures is determined as 10-11 nm. Additionally, penumbra defined as salvageable ischemic tissues performed a higher BBB permeability than infarct core. This work provides a guideline for developing nano-neuroprotectants by taking advantage of the locally enhanced BBB permeability in ischemic brain tissues.

  11. Inhibiting p38 mitogen-activated protein kinase attenuates cerebral ischemic injury in Swedish mutant amyloid precursor protein transgenic mice

    Institute of Scientific and Technical Information of China (English)

    Liangyu Zou; Haiyan Qin; Yitao He; Heming Huang; Yi Lu; Xiaofan Chu

    2012-01-01

    Cerebral ischemia was induced using photothrombosis 1 hour after intraperitoneal injection of the p38 mitogen-activated protein kinase (MAPK) inhibitor SB239063 into Swedish mutant amyloid precursor protein (APP/SWE) transgenic and non-transgenic mice. The number of surviving neurons in the penumbra was quantified using Nissl staining, and the activity of p38 MAPKs was measured by western blotting. The number of surviving neurons in the penumbra was significantly reduced in APP/SWE transgenic mice compared with non-transgenic controls 7 days after cerebral ischemia, but the activity of p38 MAPKs was significantly elevated compared with the non-ischemic hemisphere in the APP/SWE transgenic mice. SB239063 prevented these changes. The APP/SWE mutation exacerbated ischemic brain injury, and this could be alleviated by inhibiting p38 MAPK activity.

  12. Precise Characterization of the Penumbra Revealed by MRI: A Modified Photothrombotic Stroke Model Study.

    Directory of Open Access Journals (Sweden)

    Cheng Qian

    Full Text Available To precisely characterize the penumbra by MRI based on a modified photothrombotic stroke mouse model.The proximal middle cerebral artery was occluded by a convenient laser system in conjunction with an intravenous injection of Rose Bengal in mice. And the suture MCAO model was performed in seven mice as a comparison of the reproducibility. One hour after occlusion, the penumbra was defined in six random photothrombotic stroke mice by mismatch between perfusion-weighted imaging and the apparent diffusion coefficient map on a home-made workstation. After imaging, three random mice of them were chosen to perform the reperfusion surgery. And the other three mice were sacrificed to stain for several potential penumbra markers, such as c-fos and heart shock protein 90. In the remaining mice, the evolution of the lesions was detected on the apparent diffusion coefficient map, diffusion-weighted imaging and T2-weighted imaging at 1, 3, 6, 12 and 24 hours. After evaluating the neurological deficit scores, the brains were sectioned and stained by triphenyltetrazolium chloride and Nissl.The mice subjected to photothrombosis showed significant behavioral deficits. One hour after occlusion, the low perfusion areas on the perfusion-weighted imaging interlaced with the hypointense areas on the apparent diffusion coefficient map, demonstrating that the penumbra was located both surrounding and inside the lesions. This phenomenon was subsequently confirmed by the c-fos and heart shock protein 90 staining. The final T2-weighted images of the mice subjected to the reperfusion surgery were also consistent with the penumbra images at one hour. At early stages, the lesions were clearly identified on the apparent diffusion coefficient map; the volumes of the lesions on the diffusion-weighted imaging and T2-weighted imaging did not reach a maximum until 12 hours. The coefficient of variation (CV of the final lesions in the photothrombotic stroke mice was 21.7% (0.08 of

  13. Precise Characterization of the Penumbra Revealed by MRI: A Modified Photothrombotic Stroke Model Study.

    Science.gov (United States)

    Qian, Cheng; Li, Pei-Cheng; Jiao, Yun; Yao, Hong-Hong; Chen, Yu-Chen; Yang, Jian; Ding, Jie; Yang, Xiang-Yu; Teng, Gao-Jun

    2016-01-01

    To precisely characterize the penumbra by MRI based on a modified photothrombotic stroke mouse model. The proximal middle cerebral artery was occluded by a convenient laser system in conjunction with an intravenous injection of Rose Bengal in mice. And the suture MCAO model was performed in seven mice as a comparison of the reproducibility. One hour after occlusion, the penumbra was defined in six random photothrombotic stroke mice by mismatch between perfusion-weighted imaging and the apparent diffusion coefficient map on a home-made workstation. After imaging, three random mice of them were chosen to perform the reperfusion surgery. And the other three mice were sacrificed to stain for several potential penumbra markers, such as c-fos and heart shock protein 90. In the remaining mice, the evolution of the lesions was detected on the apparent diffusion coefficient map, diffusion-weighted imaging and T2-weighted imaging at 1, 3, 6, 12 and 24 hours. After evaluating the neurological deficit scores, the brains were sectioned and stained by triphenyltetrazolium chloride and Nissl. The mice subjected to photothrombosis showed significant behavioral deficits. One hour after occlusion, the low perfusion areas on the perfusion-weighted imaging interlaced with the hypointense areas on the apparent diffusion coefficient map, demonstrating that the penumbra was located both surrounding and inside the lesions. This phenomenon was subsequently confirmed by the c-fos and heart shock protein 90 staining. The final T2-weighted images of the mice subjected to the reperfusion surgery were also consistent with the penumbra images at one hour. At early stages, the lesions were clearly identified on the apparent diffusion coefficient map; the volumes of the lesions on the diffusion-weighted imaging and T2-weighted imaging did not reach a maximum until 12 hours. The coefficient of variation (CV) of the final lesions in the photothrombotic stroke mice was 21.7% (0.08 of 0.37) on T2

  14. Cardiovascular Magnetic Resonance to Predict Appropriate Implantable Cardioverter Defibrillator Therapy in Ischemic and Nonischemic Cardiomyopathy Patients Using Late Gadolinium Enhancement Border Zone: Comparison of Four Analysis Methods.

    Science.gov (United States)

    Jablonowski, Robert; Chaudhry, Uzma; van der Pals, Jesper; Engblom, Henrik; Arheden, Håkan; Heiberg, Einar; Wu, Katherine C; Borgquist, Rasmus; Carlsson, Marcus

    2017-09-01

    Late gadolinium enhancement (LGE) border zone on cardiac magnetic resonance imaging has been proposed as an independent predictor of ventricular arrhythmias. The purpose was to determine whether size and heterogeneity of LGE predict appropriate implantable cardioverter defibrillator (ICD) therapy in ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM) patients and to evaluate 4 LGE border-zone algorithms. ICM and NICM patients who underwent LGE cardiac magnetic resonance imaging prior to ICD implantation were retrospectively included. Two semiautomatic algorithms, expectation maximization, weighted intensity, a priori information and a weighted border zone algorithm, were compared with a modified full-width half-maximum and a 2-3SD threshold-based algorithm (2-3SD). Hazard ratios were calculated per 1% increase in LGE. A total of 74 ICM and 34 NICM were followed for 63 months (1-140) and 52 months (0-133), respectively. ICM patients had 27 appropriate ICD events, and NICM patients had 7 ICD events. In ICM patients with primary prophylactic ICD, LGE border zone predicted ICD therapy in univariable and multivariable analysis measured by the expectation maximization, weighted intensity, a priori information, weighted border zone, and modified full-width half-maximum algorithms (hazard ratios 1.23, 1.22, and 1.05, respectively; P<0.05; negative predictive value 92%). For NICM, total LGE by all 4 methods was the strongest predictor (hazard ratios, 1.03-1.04; P<0.05), though the number of events was small. Appropriate ICD therapy can be predicted in ICM patients with primary prevention ICD by quantifying the LGE border zone. In NICM patients, total LGE but not LGE border zone had predictive value for ICD therapy. However, the algorithms used affects the predictive value of these measures. © 2017 American Heart Association, Inc.

  15. Effect of sample size on multi-parametric prediction of tissue outcome in acute ischemic stroke using a random forest classifier

    Science.gov (United States)

    Forkert, Nils Daniel; Fiehler, Jens

    2015-03-01

    The tissue outcome prediction in acute ischemic stroke patients is highly relevant for clinical and research purposes. It has been shown that the combined analysis of diffusion and perfusion MRI datasets using high-level machine learning techniques leads to an improved prediction of final infarction compared to single perfusion parameter thresholding. However, most high-level classifiers require a previous training and, until now, it is ambiguous how many subjects are required for this, which is the focus of this work. 23 MRI datasets of acute stroke patients with known tissue outcome were used in this work. Relative values of diffusion and perfusion parameters as well as the binary tissue outcome were extracted on a voxel-by- voxel level for all patients and used for training of a random forest classifier. The number of patients used for training set definition was iteratively and randomly reduced from using all 22 other patients to only one other patient. Thus, 22 tissue outcome predictions were generated for each patient using the trained random forest classifiers and compared to the known tissue outcome using the Dice coefficient. Overall, a logarithmic relation between the number of patients used for training set definition and tissue outcome prediction accuracy was found. Quantitatively, a mean Dice coefficient of 0.45 was found for the prediction using the training set consisting of the voxel information from only one other patient, which increases to 0.53 if using all other patients (n=22). Based on extrapolation, 50-100 patients appear to be a reasonable tradeoff between tissue outcome prediction accuracy and effort required for data acquisition and preparation.

  16. Penumbra Stroke System as an ''add-on'' for the treatment of large vessel occlusive disease following thrombolysis: first results

    Energy Technology Data Exchange (ETDEWEB)

    Struffert, Tobias; Engelhorn, Tobias; Richter, Gregor; Doerfler, Arnd [University of Erlangen-Nuremberg, Department of Neuroradiology, Erlangen (Germany); Koehrmann, Martin; Nowe, Tim; Schellinger, Peter D.; Schwab, Stefan [University of Erlangen-Nuremberg, Department of Neurology, Erlangen (Germany)

    2009-09-15

    The Penumbra Stroke System (PSS) was cleared for use in patients with ischemic stroke by the FDA in January 2008. We describe our experience of using this new system in acute large vessel occlusive disease following thrombolysis. Fifteen consecutive patients (mean age 60 years) suffering from acute ischemic stroke were treated with the PSS after intravenous or intra-arterial standard treatment with tissue plasminogen activator (n = 14) or ReoPro (n = 1). All patients presented with TIMI 3 before use of the PSS. Carotid stenting (n = 3) and intracranial balloon angioplasty or stenting (n = 2) were performed if indicated. Neurological evaluation was performed using the NIHSS score and the mRS score. Initial median NIHSS score in 12 patients with occlusions in the anterior circulation was 15; three patients with basilar artery occlusion presented with coma. Median symptom to procedure start time was 151 min. In the anterior circulation, 9 of the 12 target vessels were recanalised successfully (TIMI 2 and 3). The rate of patients with independent clinical outcome (mRS {<=} 2) was 42%. One patient died 5 days after unsuccessful treatment, one after 28 days and one after 85 days owing to heart attack. Basilar artery occlusions could be recanalised in all cases to TIMI 3. The clinical result after 90 days was mRS 4 in two cases and mRS 5 in one case. Symptomatic haemorrhage did not occur. The PSS can safely be used for recanalisation in patients with acute ischemic stroke due to large vessel occlusion, who have already received thrombolysis treatment. The recanalisation rate was 80%. Symptomatic haemorrhage did not occur. Randomized trials may demonstrate that endovascular mechanical thrombectomy improves patient outcome. (orig.)

  17. Comparison of acute versus convalescent stage high-sensitivity C-Reactive protein level in predicting clinical outcome after acute ischemic stroke and impact of erythropoietin

    Directory of Open Access Journals (Sweden)

    Yeh Kuo-Ho

    2012-01-01

    Full Text Available Abstract Background and Aim Currently, no data on the optimal time point after acute ischemic stroke (IS at which high-sensitivity C-reactive protein (hs-CRP level is most predictive of unfavorable outcome. We tested the hypothesis that hs-CRP levels during both acute (48 h after IS and convalescent (21 days after IS phases are equally important in predicting 90-day clinical outcome after acute IS. We further evaluated the impact of erythropoietin (EPO, an anti-inflammatory agent, on level of hs-CRP after acute IS. Methods Totally 160 patients were prospectively randomized to receive either EPO therapy (group 1, n = 80 (5,000 IU each time, subcutaneously at 48 h and 72 h after acute IS, or placebo (group 2, n = 80. Serum level of hs-CRP was determined using ELISA at 48 h and on day 21 after IS and once in 60 healthy volunteers. Results Serum level of hs-CRP was substantially higher in all patients with IS than in healthy controls at 48 h and day 21 after IS (all p 0.5. Multivariate analysis showed that hs-CRP levels (at 48 h and day 21 were independently predictive of 90-day major adverse neurological event (MANE (defined as recurrent stroke, NIHSS≥8, or death (all p Conclusion EPO therapy which was independently predictive of freedom from 90-day MANE did not alter the crucial role of hs-CRP levels measured at 48 h and 21-day in predicting unfavorable clinical outcome after IS.

  18. The multi-component field topology of sunspot penumbrae - A diagnostic tool for spectropolarimetric measurements

    CERN Document Server

    Mueller, D A N; Fritz, G; Beck, C

    2006-01-01

    Context: Sunspot penumbrae harbor highly structured magnetic fields and flows. The moving flux tube model offers an explanation for several observed phenomena, e.g. the Evershed effect and bright penumbral grains. Aims: A wealth of information can be extracted from spectropolarimetric observations. In order to deduce the structure of the magnetic field in sunspot penumbrae, detailed forward modeling is necessary. On the one hand, it gives insight into the sensitivity of various spectral lines to different physical scenarios. On the other hand, it is a very useful tool to guide inversion techniques. In this work, we present a generalized 3D geometrical model that embeds an arbitrarily shaped flux tube in a stratified magnetized atmosphere. Methods: The new semi-analytical geometric model serves as a frontend for a polarized radiative transfer code. The advantage of this model is that it preserves the discontinuities of the physical parameters across the flux tube boundaries. This is important for the detailed ...

  19. Explanation of the sea-serpent magnetic structure of sunspot penumbrae

    CERN Document Server

    Kitiashvili, I N; Kosovichev, A G; Mansour, N N; Dalda, A Sainz; Wray, A A

    2010-01-01

    Recent spectro-polarimetric observations of a sunspot showed the formation of bipolar magnetic patches in the mid penumbra and their propagation toward the outer penumbral boundary. The observations were interpreted as being caused by sea-serpent magnetic fields near the solar surface (Sainz Dalda & Bellot Rubio 2008). In this Letter, we develop a 3D radiative MHD numerical model to explain the sea-serpent structure and the wave-like behavior of the penumbral magnetic field lines. The simulations reproduce the observed behavior, suggesting that the sea-serpent phenomenon is a consequence of magnetoconvection in a strongly inclined magnetic field. It involves several physical processes: filamentary structurization, high-speed overturning convective motions in strong, almost horizontal magnetic fields with partially frozen field lines, and traveling convective waves. The results demonstrate a correlation of the bipolar magnetic patches with high-speed Evershed downflows in the penumbra. This is the first ti...

  20. Improvement of the penumbra for small radiosurgical fields using flattening filter free low megavoltage beams

    Energy Technology Data Exchange (ETDEWEB)

    Yarahmadi, Mehran [Kurdistan Univ. of Medical Sciences, Sanandaj (Iran, Islamic Republic of); Allahverdi, Mahmoud; Nedaie, Hassan A.; Asnaashari, Khadijeh; Vaezzadeh, Sayed A. [Tehran Univ. of Medical Sciences, Tehran (Iran, Islamic Republic of); Sauer, Otto A. [Wuerzburg Univ. (Germany). Klinik und Poliklinik fuer Strahlentherapie

    2013-07-01

    Background: In stereotactic radiosurgery, sharp beam edges have clear advantages to spare normal tissues. In general, the dose gradient is a limiting factor in minimizing dose to nearby critical structures for clinical cases. Therefore the penumbral width should be diminished. Methods: A Varian Clinac 2100 linear accelerator equipped with in-house designed radiosurgical collimator was modeled using the EGSnrc/BEAMnrc Monte Carlo code and compared with the measurements. The 0.015 cm{sup 3} PinPoint chamber was used to measure the 6 MV photon beam characteristics and to validate Monte Carlo calculations. Additional to the standard (STD) linac, a flattening filter free (FFF) linac was simulated. Percent depth doses, beam profiles and output factors were calculated for small field sizes with diameter of 5, 10, 20 and 30 mm with DOSXYZnrc. The mean energy and photon fluence at the water surface were calculated with BEAMDP for both FFF linac and STD linacs. Results: The penumbra width (80%-20%) was decreased by 0.5, 0.3, 0.2 and 0.2 mm for field sizes of 5, 10, 20 and 30 mm respectively when removing the FF. The fluence of photons at the surface increased up to 3.6 times and the mean energy decreased by a factor of 0.69 when removing the FF. The penumbra width (80%-20%) decreased by 17% when a 2 MeV monoenergetic electron pencil beam incident on the target is used instead of 6.2 MeV. Conclusions: It was found that the penumbra of small field sizes is decreased by removing the FF. Likewise using low megavoltage photons reduced the beam penumbra maintaining adequate penetration and skin sparing. (orig.)

  1. The concept of the penumbra: can it be translated to stroke management?

    Science.gov (United States)

    Heiss, Wolf-Dieter

    2010-08-01

    The 'penumbra' is a concept coined in animal experiments suggesting that functionally impaired tissue can survive and recover if sufficient reperfusion is re-established within a limited time period, which depends on the level of residual flow. In an ischaemic territory, irreversible damage progresses over time from the centre of the most severe flow reduction to the periphery with less disturbed perfusion. This centrifugal progression of irreversible tissue damage is characterised by a complex cascade of interconnected electrophysiological, molecular, metabolic and perfusion disturbances. Waves of depolarisations, the peri infarct spreading depressions, inducing activation of ion pumps and liberation of excitatory transmitters play an important role in the drastically increased metabolic demand during reduced oxygen supply causing hypoxic tissue changes and lactacidosis, which further damage the tissue. Positron emission tomography allows the quantification of regional cerebral blood flow, the regional metabolic rate for oxygen and the regional oxygen extraction fraction, which can be used to identify regions with a critical reduction in these physiologic variables as indicators of penumbra and irreversible damage within ischaemic territories in animal models and patients with stroke. These positron emission tomography methods require arterial blood sampling and due to the complex logistics involved, are limited for routine application. Therefore, newer tracers were developed for the noninvasive detection of irreversible tissue damage (flumazenil) and of hypoxic tissue changes (fluoromisonidazole). As a widely applicable clinical tool, diffusion/perfusion-weighted magnetic resonance imaging is used; the 'mismatch' between perfusion and diffusion changes serves as a surrogate marker of the penumbra. However, in comparative studies of magnetic resonance imaging and positron emission tomography, diffusion-weighted imaging showed a high false-positive rate of

  2. On the fine structure of the sunspot penumbrae. II. The nature of the Evershed flow

    CERN Document Server

    Borrero, J M; Solanki, S K; Collados, M

    2005-01-01

    We investigate the fine structure of the sunspot penumbra by means of a model that allows for a flux tube in horizontal pressure balance with the magnetic background atmosphere in which it is embedded. We apply this model to spectropolarimetric observations of two neutral iron lines at 1.56 $\\mu$m and invert several radial cuts in the penumbra of the same sunspot at two different heliocentric angles. In the inner part of the penumbra we find hot flux tubes that are somewhat inclined to the horizontal. They become gradually more horizontal and cooler with increasing radial distance. This is accompanied by an increase in the velocity of the plasma and a decrease of the gas pressure difference between flux tube and the background component. At large radial distances the flow speed exceeds the critical speed and evidence is found for the formation of a shock front. These results are in good agreement with simulations of the penumbral fine structure and provide strong support for the siphon flow as the physical me...

  3. The formation of a penumbra as observed with the German VTT and SoHO/MDI

    CERN Document Server

    Schlichenmaier, Rolf; Rezaei, Reza

    2010-01-01

    The generation of magnetic flux in the solar interior and its transport to the outer solar atmosphere will be in the focus of solar physics research for the next decades. One key-ingredient is the process of magnetic flux emergence into the solar photosphere, and the reorganization to form the magnetic phenomena of active regions like sunspots and pores. On July 4, 2009, we observed a region of emerging magnetic flux, in which a proto-spot without penumbra forms a penumbra within some 4.5 hours. This process is documented by multi-wavelength observations at the German VTT: (a) imaging, (b) data with high resolution and temporal cadence acquired in Fe I 617.3 nm with the 2D imaging spectropolarimter GFPI, and (c) scans with the slit based spectropolarimeter TIP in Fe I 1089.6 nm. MDI contiuum maps and magnetograms are used to follow the formation of the proto-spot, and the subsequent evolution of the entire active region. During the formation of the penumbra, the area and the magnetic flux of the spot increase...

  4. Analytical Model of an Asymmetric Sunspot with a Steady Plasma Flow in its Penumbra

    Science.gov (United States)

    Solov'ev, A. A.; Kirichek, E. A.

    2016-08-01

    A new exact analytical solution to the stationary problem of ideal magnetohydrodynamics is derived for an unipolar asymmetric sunspot immersed in a realistic solar atmosphere. The radial and vertical profiles of pressure, plasma density, and temperature in the visible layers of the sunspot are calculated. The reduction in plasma density in the magnetic funnel of the sunspot, corresponding to the Wilson depression, is also obtained. The magnetic structure of the sunspot is given analytically in a realistic way: a part of the magnetic flux of the sunspot approaches the surrounding photosphere at the outer edge of the penumbra. The magnetic field of the sunspot is not assumed to be axially symmetric. For the first time, the angular dependence of the physical variables in this model allows us to simulate not only a deviation from the circular shape of the sunspot, but also a fine filamentary structure of the sunspot penumbra. The Alfvén Mach number (the ratio of the plasma speed to the Alfvén speed) is zero at the center of the sunspot and rises slowly toward the periphery of the sunspot; this corresponds to the structure of the Evershed flow in the penumbra. The Evershed flow in our model is mainly concentrated in dark penumbral filaments, as is observed.

  5. Volkmann ischemic contracture

    Science.gov (United States)

    Ischemic contracture - Volkmann; Compartment syndrome - Volkmann ischemic contracture ... Volkmann contracture occurs when there is a lack of blood flow (ischemia) to the forearm. This occurs when there ...

  6. Comparison of Delay-Sensitive and Delay-Insensitive Computed Tomography Perfusion Methods in Acute Ischemic Stroke and Their Variability According to Location of Critical Vascular Stenosis.

    Science.gov (United States)

    Karaalioglu, Banu; Aralasmak, Ayse; Toprak, Huseyin; Kolukisa, Mehmet; Uysal, Omer; Yildiz, Seyma; Ozdemir, Huseyin; Alkan, Alpay

    2017-08-03

    The aim of this study was to evaluate visual and quantitative differences of delay-sensitive (singular value deconvolution [SVD]) and delay-insensitive (SVD+) computed tomography perfusion (CTP) postprocessing methods in acute ischemic stroke patients and their variability according to location of critical stenosis. The CTPs of 45 patients were retrospectively processed with 2 different methods. Comparing with the contralateral normal hemisphere, relative and difference of metrics were calculated (relative cerebral blood volume, relative cerebral blood flow [rCBF], relative mean transite time [rMTT], and difference mean transite time [dMTT]). Patients were categorized into 5 groups according to superiority in visual assessment of penumbra between postprocessing methods. Locations of critical stenosis and their percentages in each group were identified and compared. Differences were formulated as (rCBF/1.4, rMTT × 1.4, dMTT/3.8) SVD = (rCBF, rMTT, dMTT) SVD+. In group 1, penumbra was noted in SVD, whereas pseudohyperperfusion was noted in SVD+. In groups 2 and 3, penumbra was better distinguished in SVD than in SVD+ in decreasing easiness, respectively. In group 4, penumbra assessment was similar in both. In group 5, penumbra was better distinguished in SVD+. Groups 1 and 5 were the groups in which the frequency of critical distal stenosis was 100%. Groups 2, 3, and 4 were the groups having high rates of proximal critical stenosis in decreasing proportions, respectively (90%, 87%, and 77%). In both CTP methods, the most prominent difference was found in dMTT. Visually, penumbra was better distinguished by SVD in proximal critical stenosis, whereas was better distinguished by SVD+ in distal critical stenosis. In cases having both ipsilateral critical proximal and distal stenoses, penumbra was noted in SVD but pseudohyperperfusion in SVD+. This finding showed that extraction of contrast delay in the SVD+ method might cause false results in cases of ipsilateral

  7. Prediction of Outcome in Neonates with Hypoxic-Ischemic Encephalopathy II: Role of Amplitude-Integrated Electroencephalography and Cerebral Oxygen Saturation Measured by Near-Infrared Spectroscopy.

    Science.gov (United States)

    Goeral, Katharina; Urlesberger, Berndt; Giordano, Vito; Kasprian, Gregor; Wagner, Michael; Schmidt, Lisa; Berger, Angelika; Klebermass-Schrehof, Katrin; Olischar, Monika

    2017-07-14

    Few data have been published on the combined use of amplitude-integrated electroencephalography (aEEG) and near-infrared spectroscopy (NIRS) for outcome prediction in neonates cooled for hypoxic-ischemic encephalopathy (HIE). Our aim was to evaluate the predictive values and the most powerful predictive combinations of single aEEG and NIRS parameters and the respective cut-off values with regard to short-term outcomes in HIE II. aEEG and NIRS were prospectively studied at the Medical University of Vienna in the first 102 h of life with regard to magnetic resonance imaging (MRI). Thirty-two neonates diagnosed with HIE II treated with hypothermia were investigated. The measurement period was divided into 6-h epochs. According to MRI, 2 outcome groups were defined and predictive values of aEEG parameters, regional cerebral oxygen saturation (rScO2), and the additional value of both methods combined were studied. Receiver operating curves (ROC) were obtained and area under the curve (AUC) values were calculated. ROC were then used to detect the optimal cut-off points, sensitivity, specificity, positive predictive values, and negative predictive values. At all time epochs, combined parameter scores were more predictive than single parameter scores. The highest AUC were observed between 18 and 60 h of cooling for the aEEG summation score (0.72-0.84) and for (background pattern + seizures) × rScO2 (0.79-0.85). At 42-60 h sensitivity was similar between those 2 scores (87.5-90.0%), but the addition of NIRS to aEEG led to an increase in specificity (from 52.4-59.1% to 72.7-90.5%). In HIE II, aEEG and NIRS are important predictors of short-term outcome. The combination of both methods improves prognostication. The highest predictive abilities were observed between 18 and 60 h of cooling. © 2017 S. Karger AG, Basel.

  8. Post-stroke gaseous hypothermia increases vascular density but not neurogenesis in the ischemic penumbra of aged rats

    DEFF Research Database (Denmark)

    Sandu, Raluca Elena; Uzoni, Adriana; Ciobanu, Ovidiu

    2016-01-01

    Purpose: In aged humans, stroke is a major cause of disability for which no neuroprotective measures are available. In animal studies of focal ischemia, short-term hypothermia often reduces infarct size. Nevertheless, efficient neuroprotection requires long-term, regulated lowering of whole body...... temperature. Previously, we reported that post-stroke exposure to hydrogen sulfide (H2S) effectively lowers whole body temperature and confers neuroprotection in aged animals. Methods: In the present study using behavioral tests, MRI, telemetrical EEG, BP and temperature recordings, RT...

  9. Visualization of in vivo metabolic flows reveals accelerated utilization of glucose and lactate in penumbra of ischemic heart

    OpenAIRE

    Yuki Sugiura; Yoshinori Katsumata; Motoaki Sano; Kurara Honda; Mayumi Kajimura; Keiichi Fukuda; Makoto Suematsu

    2016-01-01

    Acute ischemia produces dynamic changes in labile metabolites. To capture snapshots of such acute metabolic changes, we utilized focused microwave treatment to fix metabolic flow in vivo in hearts of mice 10 min after ligation of the left anterior descending artery. The left ventricle was subdivided into short-axis serial slices and the metabolites were analyzed by capillary electrophoresis mass spectrometry and matrix-assisted laser desorption/ionization imaging mass spectrometry. These tech...

  10. Modern imaging of the infarct core and the ischemic penumbra in acute stroke patients: CT versus MRI.

    Science.gov (United States)

    Ledezma, Carlos J; Fiebach, Jochen B; Wintermark, Max

    2009-04-01

    Thrombolysis has become an approved therapy for acute stroke. However, many stroke patients do not benefit from such treatment, since the presently used criteria are very restrictive, notably with respect to the accepted time window. Even so, a significant rate of intracranial hemorrhage still occurs. Conventional cerebral computed tomography (CT) without contrast has been proposed as a selection tool for acute stroke patients. However, more-modern MRI and CT techniques, referred to as diffusion- and perfusion-weighted imaging and perfusion-CT, have been introduced, which afford a comprehensive noninvasive survey of acute stroke patients as soon as their emergency admission, with accurate demonstration of the site of arterial occlusion and its hemodynamic and pathophysiological repercussions for the brain parenchyma. The objective of this article is to present the advantages and drawbacks of CT and MRI in the evaluation of acute stroke patients.

  11. Systematic review and meta-analysis of vascular imaging features to predict outcome following intravenous rtPA for acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Ricardo C Nogueira

    2016-05-01

    Full Text Available Background: The present review investigated which findings in vascular imaging techniques can be used to predict clinical outcome and risk of symptomatic intracerebral haemorrhage (sICH in patients who underwent intravenous thrombolytic treatment. Methods: Publications were searched and inclusion criteria were as follows: 1 published manuscripts, 2 patients with acute ischemic stroke managed with intravenous rtPA, and 3 availability of imaging assessment to determine vessel patency or regulation of cerebral blood flow prior to, during and/or after thrombolytic treatment. Clinical outcomes were divided into neurological outcome (NIHSS within 7 days and functional outcome (modified Rankin score in 2 – 3 months. sICH was defined as rtPA-related intracerebral bleeding associated with any worsening of NIHSS. Results: Thirty-nine articles were selected. Recanalization was associated with improved neurological and functional outcome (OR=7.83; 95% CI, 3.71 – 16.53 and OR=11.12; 95% CI, 5.85 – 21.14; p<0.001 respectively. Both tandem internal carotid artery/middle cerebral artery (ICA/MCA occlusions and isolated ICA occlusion had worse functional outcome than isolated MCA occlusion (OR=0.26, 95% CI, 0.12 – 0.52; p<0.001 and OR=0.24, 95% CI, 0.07 – 0.77; p=0.016, respectively. Re-occlusion was associated with neurological deterioration (OR=6.48, 95% CI, 3.64 – 11.56; p<0.001 and early recanalization was associated with lower odds of symptomatic intracerebral haemorrhage (OR=0.36, 95% CI, 0.18 – 0.70; p=0.003 Conclusion: Brain circulation data before, during and after thrombolysis may be useful for predicting clinical outcome. Cerebral arterial recanalization, presence and site of occlusion, and re-occlusion are all important in predicting clinical outcome.

  12. Evaluation of global longitudinal strain of left ventricle and regional longitudinal strain in the region of left ventricular leads predicts the response to cardiac resynchronization therapy in patients with ischemic heart failure.

    Science.gov (United States)

    Ma, Chun-Yan; Liu, Shuang; Yang, Jun; Tang, Li; Zhang, Li-Ming; Li, Nan; Yu, Bo

    2014-09-01

    Myocardium viability in ischemic heart failure (HF) may affect the effect of cardiac resynchronization therapy (CRT). We hypothesized that longitudinal strain of 2D-STE, which reflects myocardium viability, can predict the response to CRT in patients with ischemic HF. 2D-STE was performed in 42 patients with HF, 1 week before and 1 year after CRT. GLS, RLS, and the LV synchrony index (SI), defined as the difference in timing to peak radial strain between LV anterior septal and posterior wall in LV short axis view, were calculated. A decrease in the LV end-systolic volume (LVESV) value of ≥ 15 % 1 year after CRT was defined as response to CRT. Twenty-nine patients responded to CRT (CRT-R group), while 13 patients did not respond and were assigned as CRT-NR group. Pre-CRT RLS and GLS were higher, while SI is lower, in CRT-R patients compared with CRT-NR group (p < 0.001). The ROC curve revealed that RLS of -11.5 % predicted response to CRT with sensitivity of 80.0 % and specificity of 77.9 % (AUC = 0.84, p < 0.001). Further, GLS of -13 % predicted response to CRT with sensitivity of 73.0 % and specificity of 73.4 % (AUC = 0.79, p < 0.001). In conclusion, LV dyssynchrony, GLS, and RLS calculated by 2D-STE can predict long-term response to CRT in patients with ischemic HF.

  13. Impaired glucose regulation predicted 1-year mortality of Chinese patients with ischemic stroke: data from abnormal glucose regulation in patients with acute stroke across China.

    Science.gov (United States)

    Jia, Qian; Liu, Gaifen; Zheng, Huaguang; Zhao, Xingquan; Wang, Chunxue; Wang, Yilong; Liu, Liping; Wang, Yongjun

    2014-05-01

    It remains uncertain if impaired glucose regulation (IGR) as a predictor for stroke outcomes. This study aimed at observing the effect of IGR on the 1-year outcomes in Chinese patients with ischemic stroke. Patients with acute ischemic stroke were recruited consecutively in multihospitals across China. Oral glucose tolerance test was performed to identify IGR. Cox proportion hazard model was performed to investigate the effect of IGR on 1-year mortality or stroke recurrence in patients with ischemic stroke. The study recruited 2639 patients with ischemic stroke. IGR was shown as an independent risk factor for the mortality of patients with ischemic stroke (hazard ratio [95% confidence interval], 3.088 [1.386-6.884]; P=0.006). However, IGR showed no significant effects on the dependency or stroke recurrence of patients (P=0.540 and 0.618, respectively). IGR was an independent predictor for the mortality of patients with ischemic stroke. IGR should be highlighted and intervened actively in the patients with ischemic stroke.

  14. Therapeutic hypothermia does not diminish the vital and necessary role of SSEP in predicting unfavorable outcome in anoxic-ischemic coma.

    Science.gov (United States)

    Rothstein, Ted L

    2014-11-01

    Rational medical management of patients who remain comatose following cardio-pulmonary resuscitation (CPR) due to anoxic-ischemic encephalopathy depends upon the early identification of those with a hopeless prognosis - regardless of how aggressively they are managed. Conversely, it is mandatory that we recognize those patients with the potential to recover in order to institute aggressive therapeutic measures. The bilateral absence of the N20 Cortical Somatosensory Evoked Potential has been identified as the most reliable predictor of an unfavorable prognosis in normothermic patients. Two randomized trials have determined that mild therapeutic hypothermia (TH) delivered immediately after CPR improves neurologic outcomes. TH has now become the standard of care in the management of patients with cardio-pulmonary arrest. Eight studies targeting patients who were comatose following CPR, treated with TH, and using SSEP as an outcome predictor are reviewed. There is only one patient treated with TH who appears to have fully recovered following cardiac arrest who was initially found to have bilateral absent cortical potentials. This opinion paper will address whether the criteria that placed reliance upon SSEP to predict unfavorable outcome in post cardio-pulmonary arrest patients after receiving TH, still apply.

  15. 短暂性脑缺血发作的近期卒中风险预测%Prediction of short-term stroke risk after transient ischemic attack

    Institute of Scientific and Technical Information of China (English)

    刘宏顺; 张春良; 顾莹辉

    2011-01-01

    短暂性脑缺血发作(transient ischemic attack,TIA)短期内发生卒中的风险很高.对TIA的近期卒中风险做出预测,快速筛选高危患者,并采取有效治疗措施,可以减少卒中的发生.文章对目前TIA后近期卒中风险预测的相关研究进行了综述.%The risk of stroke occurrence in a short time in patients with transient ischemic attack (TIA) is very high.Predicting short-term stroke risk after TIA,rapidly screening of high-risk patients and taking effective treatment measures may decrease the occurrence of stroke.This article reviews the present related research of predicting short-term stroke risk after TIA.

  16. Prediction of Appropriate Shocks Using 24-Hour Holter Variables and T-Wave Alternans After First Implantable Cardioverter-Defibrillator Implantation in Patients With Ischemic or Nonischemic Cardiomyopathy.

    Science.gov (United States)

    Seegers, Joachim; Bergau, Leonard; Expósito, Pascal Muñoz; Bauer, Axel; Fischer, Thomas H; Lüthje, Lars; Hasenfuß, Gerd; Friede, Tim; Zabel, Markus

    2016-07-01

    In patients treated with implantable cardioverter defibrillator (ICD), prediction of both overall survival and occurrence of shocks is important if improved patient selection is desired. We prospectively studied the predictive value of biomarkers and indexes of cardiac and renal function and spectral microvolt T-wave alternans testing and 24-hour Holter variables in a population who underwent first ICD implantation. Consecutive patients in sinus rhythm with ischemic or dilated cardiomyopathy scheduled for primary or secondary prophylactic ICD implantation were enrolled. Exercise microvolt T-wave alternans and 24-hour Holter for number of ventricular premature contractions (VPCs), deceleration capacity, heart rate variability, and heart rate turbulence were done. Death of any cause and first appropriate ICD shock were defined as end points. Over 33 ± 15 months of follow-up, 36 of 253 patients (14%) received appropriate shocks and 39 of 253 patients (15%) died. Only 3 of 253 patients (1%) died after receiving at least 1 appropriate shock. In univariate analyses, New York Heart Association class, ejection fraction, N-terminal pro brain-type natriuretic peptide (NT-proBNP), renal function, ICD indication, deceleration capacity, heart rate variability, and heart rate turbulence were predictive of all-cause mortality and VPC number and deceleration capacity predicted first appropriate shock. NT-proBNP (≥1,600 pg/ml) was identified as the only independent predictor of all-cause mortality (hazard ratio 3.0, confidence interval 1.3 to 7.3, p = 0.014). In contrast, VPC number predicted appropriate shocks (hazard ratio 2.3, confidence interval 1.0 to 5.5, p = 0.047) as the only independent risk marker. In conclusion, NT-proBNP is a strong independent predictor of mortality in a typical prospective cohort of newly implanted patients with ICD, among many electrocardiographic and clinical variables studied. Number of VPCs was identified as a predictor of appropriate shocks

  17. [Pathophysiology of brain injury and targets of treatment in acute ischemic stroke].

    Science.gov (United States)

    Tanaka, Kortaro

    2013-01-01

    Brain is very vulnerable to ischemia, and exhibits various functional impairments in a flow-dependent manner. After onset of ischemia, the following cascade ensues propagating from the ischemic core to the surrounding area; ischemic depolarization, excitatory cellular injury induced by Ca(2+) and glutamate, oxidative injury induced by reactive oxygen species including various free radicals, secondary microcirculatory disturbance, edema formation, apoptosis and inflammation. Intrinsic protective responses are also activated at the periphery of ischemic area. From the clinical view point, urgent detection of "penumbra" area by imaging modalities such as diffusion-perfusion mismatch and rescuing this area from evolving into irreversible damage (infarction) are the most important issues. Therapeutic targets in the acute phase of cerebral infarction consist of vascular therapy including acute thrombolysis, prevention of microcirculatory disturbance, protection of blood brain barrier and promotion of collateral blood flow, and cellular therapy such as neuroprotective measures aiming at neurovascular unit.

  18. Phase I and Phase II Therapies for Acute Ischemic Stroke: An Update on Currently Studied Drugs in Clinical Research

    Science.gov (United States)

    Reis, Cesar; Akyol, Onat; Ho, Wing Mann; Araujo, Camila; Huang, Lei; Applegate II, Richard

    2017-01-01

    Acute ischemic stroke is a devastating cause of death and disability, consequences of which depend on the time from ischemia onset to treatment, the affected brain region, and its size. The main targets of ischemic stroke therapy aim to restore tissue perfusion in the ischemic penumbra in order to decrease the total infarct area by maintaining blood flow. Advances in research of pathological process and pathways during acute ischemia have resulted in improvement of new treatment strategies apart from restoring perfusion. Additionally, limiting the injury severity by manipulating the molecular mechanisms during ischemia has become a promising approach, especially in animal research. The purpose of this article is to review completed and ongoing phases I and II trials for the treatment of acute ischemic stroke, reviewing studies on antithrombotic, thrombolytic, neuroprotective, and antineuroinflammatory drugs that may translate into more effective treatments. PMID:28286764

  19. Phase I and Phase II Therapies for Acute Ischemic Stroke: An Update on Currently Studied Drugs in Clinical Research.

    Science.gov (United States)

    Reis, Cesar; Akyol, Onat; Ho, Wing Mann; Araujo, Camila; Huang, Lei; Applegate, Richard; Zhang, John H

    2017-01-01

    Acute ischemic stroke is a devastating cause of death and disability, consequences of which depend on the time from ischemia onset to treatment, the affected brain region, and its size. The main targets of ischemic stroke therapy aim to restore tissue perfusion in the ischemic penumbra in order to decrease the total infarct area by maintaining blood flow. Advances in research of pathological process and pathways during acute ischemia have resulted in improvement of new treatment strategies apart from restoring perfusion. Additionally, limiting the injury severity by manipulating the molecular mechanisms during ischemia has become a promising approach, especially in animal research. The purpose of this article is to review completed and ongoing phases I and II trials for the treatment of acute ischemic stroke, reviewing studies on antithrombotic, thrombolytic, neuroprotective, and antineuroinflammatory drugs that may translate into more effective treatments.

  20. Phase I and Phase II Therapies for Acute Ischemic Stroke: An Update on Currently Studied Drugs in Clinical Research

    Directory of Open Access Journals (Sweden)

    Cesar Reis

    2017-01-01

    Full Text Available Acute ischemic stroke is a devastating cause of death and disability, consequences of which depend on the time from ischemia onset to treatment, the affected brain region, and its size. The main targets of ischemic stroke therapy aim to restore tissue perfusion in the ischemic penumbra in order to decrease the total infarct area by maintaining blood flow. Advances in research of pathological process and pathways during acute ischemia have resulted in improvement of new treatment strategies apart from restoring perfusion. Additionally, limiting the injury severity by manipulating the molecular mechanisms during ischemia has become a promising approach, especially in animal research. The purpose of this article is to review completed and ongoing phases I and II trials for the treatment of acute ischemic stroke, reviewing studies on antithrombotic, thrombolytic, neuroprotective, and antineuroinflammatory drugs that may translate into more effective treatments.

  1. Prediction of intermittent claudication, ischemic stroke, and other cardiovascular disease by detection of abdominal aortic calcific deposits by plain lumbar radiographs.

    Science.gov (United States)

    Levitzky, Yamini S; Cupples, L Adrienne; Murabito, Joanne M; Kannel, William B; Kiel, Douglas P; Wilson, Peter W F; Wolf, Philip A; O'Donnell, Christopher J

    2008-02-01

    There has been little attention to vascular calcium testing for generalized assessment of cardiovascular disease (CVD) outcomes, such as intermittent claudication (IC) and ischemic stroke (IS). We hypothesize that aortic calcium is an important predictor of CVD outcomes. Lumbar x-rays were obtained in 848 men and 1,301 women (mean ages 59.7 and 60.1 years, respectively) from the original cohort of the Framingham Heart Study. Abdominal aortic calcium (AAC) deposits were graded using a previously validated scale. Participants were categorized according to a 10-year Framingham coronary heart disease (CHD) risk score. Multivariable Cox proportional hazards analyses were performed to relate AAC to CVD outcomes. There were 199 IC events, 201 IS events, 702 CHD events, and 1,121 CVD events during 32 years of follow-up. Multivariable adjusted hazard ratios for the third versus first AAC tertile in the combined cohort were 1.68 (95% confidence interval [CI] 1.12 to 2.50) for IC, 1.73 (95% CI 1.12 to 2.65) for IS, 1.59 (95% CI 1.26 to 2.00) for CHD, and 1.64 (95% CI 1.37 to 1.97) for CVD. Hazard ratios for IC and IS were similar in magnitude to those for CHD and CVD. A high AAC score was associated with significantly higher incidence of events in subjects at intermediate Framingham CHD risk for all end points. Risk prediction based on cardiovascular risk factors improved for most outcomes when AAC was added. In conclusion, there was a graded, increasing, and independent association of AAC with incident IC and IS, similar in magnitude to risks predicted for CHD and CVD. AAC appears to be useful for risk stratification in patients at intermediate CHD risk.

  2. Outcome of bypass surgery in patients with chronic ischemic left ventricular dysfunction. Predictive value of MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kloew, N.E. [The National Hospital, Oslo (Norway). Dept. of Radiology; Smith, H.J. [The National Hospital, Oslo (Norway). Dept. of Radiology; Gullestad, L. [The National Hospital, Oslo (Norway). Dept. of Cardiology; Seem, E. [The National Hospital, Oslo (Norway). Dept. of Cardiovascular Surgery; Endresen, K. [The National Hospital, Oslo (Norway). Dept. of Cardiology

    1997-01-01

    Purpose: To determine the preoperative findings of MR imaging of the left ventricle (LV) that could best predict the functional outcome of the LV after surgical revascularization. Material and Methods: Patients with angina pectoris, previous myocardial infarction, and dysfunction of the LV, and who had a preoperative cine MR, were re-evaluated after bypass surgery with MR in a study on the effects of revascularization after mean 22 months. Results: Angina pectoris was relieved in all patients except one, but the maximum workload during the exercise test was increased in only 3 patients. Coronary angiography showed that 37 of 45 (82%) of the distal anastomoses were open. The LV ejection fraction was the same before and after operation both at angiography and MR imaging. MR showed LV end-diastolic volume to be increased from 190{+-}50 ml to 250{+-}70 ml. Compared to angiography, MR provided additional information regarding myocardial wall thickness and function, and the size of myocardial infarction. Improvement in systolic wall thickening was seen in 65% of the segments that had had an end-diastolic wall thickness (EDWT) greater than 15 mm before operation, while only 4% of the segments with EDWT<6 mm improved. In the wall thickness range of 6-15 mm, MR was unable to predict the functional outcome of the LV. Conclusion: Preoperative MR findings of thick myocardial walls with poor function seem predictive of improved function after revascularization. When the LV wall thickness is less than 6 mm, no improvement should be expected. (orig.).

  3. Bacterial pneumonia following acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Li-Fu Chen

    2013-02-01

    Conclusion: Pneumonia after acute ischemic stroke is a severe complication. Once stroke-related pneumonia develops, neurologic assessment, CURB-65 score, and shock can be used to predict the ultimate prognosis.

  4. Imaging the ischaemic penumbra after acute ischaemic stroke using PET and {sup 18}F-Fluoromisonidazole

    Energy Technology Data Exchange (ETDEWEB)

    Read, S.J.; Hirano, T.; Abbott, D.F.; Sachinidis, J.I.; Tochon-Danguy, H.J.; Chan, J.G.; Egan, F.; Scott, A.M.; Bladin, C.F.; McKay, W.J.; Donna, G.A. [Austin and Repatriation Medical Centre, Melbourne, VIC (Australia). Departments of Neurology, Nuclear Medicine and Centre for Positron Emission Tomogrpahy]|[University of Melbourne, Melbourne, VIC (Australia). Department of Medicine

    1998-06-01

    Full text: Using PET with {sup 15}O-labelled oxygen and water, the ischaemic penumbra is currently defined as peri-infarct areas demonstrating misery perfusion. We have used PET with the hypoxic tissue marker {sup l8}F-fluoromisonidazole ({sup 18}F-FMISO) to detect hypoxic but viable peri-infarct tissue in patients after acute ischaemic stroke. Fifteen patients with acute ischaemic strokes were studied using PET and {sup 18}F-FMISO. Studies were performed within 48 hours of stroke in 7 patients, at 6-11 days after stroke in 2 patients, and serially during both time epochs in 6 patients. We objectively assessed tracer uptake using a statistically-based image thresholding method. The mean activity in the contralateral (normal) hemisphere was calculated, and the whole image thresholded so that pixels with activity > 3 SD above the mean were identified. Positive studies were those with high activity pixels ipsilateral to the infarct. Hypoxic tissue was detected in peri-infarct regions in 9 of the 13 patients studied within 48 hours of stroke. These areas were generally distributed in the peripheries of the final infarct volume. None of the 8 patients studied 6-11 days after stroke exhibited increased {sup I8}F- FMISO activity. The 6 patients studied both early and late all exhibited areas of increased activity on the early but not the late study, consistent with resolution of the penumbra by this time. The distribution of the hypoxic tissue identified with this method supports the hypothesis that these tissues are likely to comprise the ischaemic penumbra.

  5. Coupling of the magnetic field and gas flows inferred from the net circular polarization in a sunspot penumbra

    Science.gov (United States)

    Shaltout, Abdelrazek M. K.; Ichimoto, Kiyoshi

    2015-04-01

    We analyze penumbral fine structure using high-resolution spectropolarimetric data obtained by the Solar Optical Telescope on board the Hinode satellite. The spatial correlation between the net circular polarization (NCP) and Evershed flow is investigated in detail. Here we obtain that negative NCP structures are correlated with the Evershed flow channels in the limb-side penumbra, and that negative NCP or depressions of positive NCP are associated with the Evershed flow channels in the disk center-side of the penumbra for a negative-polarity sunspot in NOAA 10923. The positive NCP dominant in the disk center-side penumbra is essentially attributed to interflow channels instead of Evershed flow channels. The stratification of magnetic field and velocity are investigated by using SIR-JUMP inversion with a one-component atmosphere, and the NCP of spectral lines in the limb-side and disk center-side of the penumbra is successfully reproduced. The inversion results show that an increased Evershed flow is associated with a strong magnetic field located in the deep photosphere. Our result does not match with the simple two-component penumbral models in which the penumbra consists of Evershed flow and interflow channels and the global NCP is attributed only to the Evershed flow channels.

  6. Endoplasmic reticulum stress-induced apoptosis in the penumbra aggravates secondary damage in rats with traumatic brain injur y

    Institute of Scientific and Technical Information of China (English)

    Guo-zhu Sun; Fen-fei Gao; Zong-mao Zhao; Hai Sun; Wei Xu; Li-wei Wu; Yong-chang He

    2016-01-01

    Neuronal apoptosis is mediated by intrinsic and extrinsic signaling pathways such as the membrane-mediated, mitochondrial, and endo-plasmic reticulum stress pathways. Few studies have examined the endoplasmic reticulum-mediated apoptosis pathway in the penumbra after traumatic brain injury, and it remains unclear whether endoplasmic reticulum stress can activate the caspase-12-dependent apoptotic pathway in the traumatic penumbra. Here, we established rat models of lfuid percussion-induced traumatic brain injury and found that protein expression of caspase-12, caspase-3 and the endoplasmic reticulum stress marker 78 kDa glucose-regulated protein increased in the traumatic penumbra 6 hours after injury and peaked at 24 hours. Furthermore, numbers of terminal deoxynucleotidyl transferase-mediat-ed dUTP nick end labeling-positive cells in the traumatic penumbra also reached peak levels 24 hours after injury. These ifndings suggest that caspase-12-mediated endoplasmic reticulum-related apoptosis is activated in the traumatic penumbra, and may play an important role in the pathophysiology of secondary brain injury.

  7. Ischemic preconditioning protects against ischemic brain injury

    Directory of Open Access Journals (Sweden)

    Xiao-meng Ma

    2016-01-01

    Full Text Available In this study, we hypothesized that an increase in integrin αv ß 3 and its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αv ß 3, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αv ß 3 and vascular endothelial growth factor levels in the brain following ischemia.

  8. On the temperature and velocity through the photosphere of a sunspot penumbra

    Science.gov (United States)

    del Toro Iniesta, J. C.; Tarbell, T. D.; Ruiz Cobo, B.

    1994-11-01

    We investigate the structure in depth of a sunspot penumbra by means of the inversion code of the radiative transfer equation proposed by Ruiz Cobo & del Toro Iniesta (1992), applied to a set of filtergrams of a sunspot, scanning the Fe I line at 5576.1 A, with a sampling interval of 30 mA, from -120 to 120 mA from line center (data previously analyzed by Title et al. 1993). The temperature structure of this penumbra is obtained for each of the 801 pixels selected (0.32 sec x 0.32 sec). On the average, the temperatures seem to decrease as we move inward, but the differences are of the order of the rms values (approximately equal 100-200 K) at a given distance to sunspot center. The outer parts of the penumbra have also a bigger curvature in the T versus log tau5 relation than the inner parts. We realize, however, that these differences might be influenced by possible stray light effects. Compared to the quiet Sun, penumbral temperatures are cooler at deep layers and hotter at high layers. A mean penumbral model atmosphere is presented. The asymmetries observed in the intensity profile (the line is magnetically insensitive) are deduced to be produced by strong gradients of the line-of-sight velocity that sharply vary spatially along slices of almost constant distance to sunspot center. These variations suggest that such gradients are not only needed to explain the broadband circular polarization observed in sunspots (see Sanchez Almeida & Lites 1992) but are a main characteristic of the fine-scale penumbra. The results are compatible with an Evershed flow present everywhere, but its gradient with depth turns out to vary so that the flow seems to be mainly concentrated in some penumbral fibrils when studied through Dopplergrams. Finally, as by-products of this study, we put constraints to the practical usefulness of the Eddington-Barbier relation, and we explain the values of the Fourier Dopplergrams to be carrying information of layers around the centroid of the

  9. Independence, Intervention and Great Power Patronage: Kosovo, Georgia and the Contemporary Self-Determination Penumbra

    Directory of Open Access Journals (Sweden)

    Aidan Hehir

    2009-01-01

    Full Text Available This article contends that despite the increased currency of self-determination in contemporary international political debate the issue remains highly ambiguous and problematic. Two situation in 2008 - Kosovo’s declaration of independence and Russia’s recognition of South Ossetia and Abkhazia – brought this issue to the top of the international agenda and yet neither case has clarified the self-determination penumbra. The issue remains the preserve of political expediency rather than objective legal doctrine. This article assesses the evolution of independence Kosovo highlighting the highly contingent nature of this case and the conditional nature of Kosovo’s “independence”

  10. Photodynamic impact induces ischemic tolerance in models in vivo and in vitro

    Science.gov (United States)

    Demyanenko, Svetlana; Sharifulina, Svetlana; Berezhnaya, Elena; Kovaleva, Vera; Neginskaya, Maria; Zhukovskaya, Ludmila

    2016-04-01

    Ischemic tolerance determines resistance to lethal ischemia gained by a prior sublethal stimulus (i.e., preconditioning). We reproduced this effect in two variants. In vitro the preliminary short (5 s) photodynamic treatment (PDT) (photosensitizer Photosens, 10 nM, 30 min preincubation; laser: 670 nm, 100 mW/cm2) significantly reduced the necrosis of neurons and glial cells in the isolated crayfish stretch receptor, which was caused by following 30-min PDT by 66% and 46%, respectively. In vivo PDT of the rat cerebral cortex with hydrophilic photosensitizer Rose Bengal (i.v. administration, laser irradiation: 532 nm, 60 mW/cm2, 3 mm beam diameter, 30 min) caused occlusion of small brain vessels and local photothrombotic infarct (PTI). It is a model of ischemic stroke. Cerebral tissue edema and global necrosis of neurons and glial cells occurred in the infarction core, which was surrounded by a 1.5 mm transition zone, penumbra. The maximal pericellular edema, hypo- and hyperchromia of neurons were observed in penumbra 24 h after PTI. The repeated laser irradiation of the contralateral cerebral cortex also caused PTI but lesser as compared with single PDT. Preliminary unilateral PTI provided ischemic tolerance: at 14 day after second exposure the PTI volume significantly decreased by 24% than in the case of a single exposure. Sensorimotor deficits in PDT-treated rats was registered using the behavioral tests. The preliminary PTI caused the preconditioning effect.

  11. The electrical current density vector in the inner penumbra of a Sunspot

    CERN Document Server

    Puschmann, K G; Pillet, V Martínez

    2010-01-01

    We determine the entire electrical current density vector in a geometrical 3D volume of the inner penumbra of a sunspot from an inversion of spectropolarimetric data obtained with Hinode/SP. Significant currents are seen to wrap around the hotter, more elevated regions with lower and more horizontal magnetic field that harbor strong upflows and radial outflows (the intraspines). The horizontal component of the current density vector is 3-4 times larger than the vertical; nearly all previous studies only obtain the vertical component and thus strongly underestimate the current density. The current density and the magnetic field vectors form an angle of about 20 degrees. The plasma beta at the 0 km level is larger than 1 in the intraspines and is one order of magnitude lower in the background component of the penumbra (spines). At the 200 km level, the plasma beta is below 0.3 nearly everywhere. The plasma beta surface as well as the surface optical depth unity are very corrugated. At the borders of intraspines...

  12. Parameters of magnetic stimulation of the brain and somatosensory evoked potentials in the prediction of recovery of motor functions after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Irina Vladimirovna Sidyakina

    2011-01-01

    Full Text Available Objective: to estimate the significance of parameters of transcranial magnetic stimulation (TMS of the brain and somatosensory evoked potentials (SSEPs in the prediction of recovery of motor functions after ischemic stroke. Patients and methods. The study enrolled 63 patients (29 women and 34 men aged 41-5 years in the acutest period of middle cerebral artery (MCA basin infarct with evolving hemiplegia. In the first 5 days after stroke, TMS was performed in the projection of the motor cortex of the involved hemisphere, by recording a motor evoked response (MER from m. tibialis anterior and m. pollicis brevis in hemiplegia; and SSEPs were recorded when stimulating n. medianus and n. tibialis in hemiplegia. The outcomes were assessed a year after stroke: muscle strength on a scale from 0 to 5 e and the Rivermead mobility index were studied. Results. A year later, there was either partial or full recovery of active lower and upper limb movements in 73.3 and 58.2%, respectively. With good and poor motor outcomes, the parameters of MCA rather than SSEPs differed significantly. The optimal threshold amplitude for MER from the lower and upper limbs was 0.25 and 0.3 mW, respectively; the time of central motor conduction was 22 and 19 msec for the lower and upper limbs, respectively. At the same time, TMS findings were insufficient for predicting a patient's mobility. The prognosis was determined by the data of TMS and the results of SSEPs: the best outcomes in movement recovery were noted when the prognosis was positive according to the data of TMS in combination with the preserved parameters of SSEPs in the study of cortical projections of the lower limb. Conclusion. It is expedient to perform TMS to estimate the probability of muscle strength recovery. The SSEPs method cannot determine the prognosis of muscle strength recovery; however, its results are of importance for estimating the promises of recovering a patient's mobility. Therefore

  13. Transient Ischemic Attack

    Medline Plus

    Full Text Available Transient Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood ... The only difference between a stroke and TIA is that with TIA the blockage is transient (temporary). ...

  14. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an artery for a short time. The only difference between a stroke ...

  15. Reperfusion Therapies for Acute Ischemic Stroke: An Update

    Science.gov (United States)

    Dorado, Laura; Millán, Mònica; Dávalos, Antoni

    2014-01-01

    Acute ischemic stroke is a major cause of morbidity and mortality in developed countries. Intravenous thrombolysis with tissue plasminogen activator (tPA) within 4.5 hours of symptoms onset significantly improves clinical outcomes in patients with acute ischemic stroke. This narrow window for treatment leads to a small proportion of eligible patients to be treated. Intravenous or intra-arterial trials, combined intravenous/intra-arterial trials, and newer devices to mechanically remove the clot from intracranial arteries have been investigated or are currently being explored to increase patient eligibility and to improve arterial recanalization and clinical outcome. New retrievable stent-based devices offer higher revascularization rates with shorter time to recanalization and are now generally preferred to first generation thrombectomy devices such as Merci Retriever or Penumbra System. These devices have been shown to be effective for opening up occluded vessels in the brain but its efficacy for improving outcomes in patients with acute stroke has not yet been demonstrated in a randomized clinical trial. We summarize the results of the major systemic thrombolytic trials and the latest trials employing different endovascular approaches to ischemic stroke. PMID:24646159

  16. Cerebral Blood Volume ASPECTS Is the Best Predictor of Clinical Outcome in Acute Ischemic Stroke: A Retrospective, Combined Semi-Quantitative and Quantitative Assessment.

    Directory of Open Access Journals (Sweden)

    Marina Padroni

    Full Text Available The capability of CT perfusion (CTP Alberta Stroke Program Early CT Score (ASPECTS to predict outcome and identify ischemia severity in acute ischemic stroke (AIS patients is still questioned.62 patients with AIS were imaged within 8 hours of symptom onset by non-contrast CT, CT angiography and CTP scans at admission and 24 hours. CTP ASPECTS was calculated on the affected hemisphere using cerebral blood flow (CBF, cerebral blood volume (CBV and mean transit time (MTT maps by subtracting 1 point for any abnormalities visually detected or measured within multiple cortical circular regions of interest according to previously established thresholds. MTT-CBV ASPECTS was considered as CTP ASPECTS mismatch. Hemorrhagic transformation (HT, recanalization status and reperfusion grade at 24 hours, final infarct volume at 7 days and modified Rankin scale (mRS at 3 months after onset were recorded.Semi-quantitative and quantitative CTP ASPECTS were highly correlated (p<0.00001. CBF, CBV and MTT ASPECTS were higher in patients with no HT and mRS ≤ 2 and inversely associated with final infarct volume and mRS (p values: from p<0.05 to p<0.00001. CTP ASPECTS mismatch was slightly associated with radiological and clinical outcomes (p values: from p<0.05 to p<0.02 only if evaluated quantitatively. A CBV ASPECTS of 9 was the optimal semi-quantitative value for predicting outcome.Our findings suggest that visual inspection of CTP ASPECTS recognizes infarct and ischemic absolute values. Semi-quantitative CBV ASPECTS, but not CTP ASPECTS mismatch, represents a strong prognostic indicator, implying that core extent is the main determinant of outcome, irrespective of penumbra size.

  17. On the Formation of Penumbrae as Observed with the German VTT SOHO/MDI, and SDO/HMI

    Science.gov (United States)

    Schlichenmaier, R.; Rezaei, R.; González, N. B.

    2012-05-01

    Solar magnetic fields are generated in the solar interior and pop up at the solar surface to form active regions. As the magnetic field appears on the surface, it forms various structures like small magnetic elements, pores, and sunspots. The nature of these formation processes is largely unknown. In this contribution we elaborate on the formation of sunspots and particularly on the formation of penumbrae. We report on observations that we obtained at the German Vacuum Tower Telescope (VTT) on July 4, 2009 on the formation of the spot in AR 11024. This data set is complemented with data from the Michelson Doppler Imager (MDI) aboard SOHO, which offers an entire time coverage. Moreover, the evolution of AR 11024 is compared with a particular event of penumbra formation in AR 11124 around November 13, 2010, using intensity images from the Helioseismic and Magnetic Imager (HMI) onboard SDO. We conclude that two processes contribute to the increase of the magnetic flux of a sunspot: (1) merging pores, and (2) emerging bipoles of which the spot polarity migrates towards and merges with the spot. As the penumbra forms, the area, magnetic flux, and maximum field strength in the umbra stay constant or increase slightly, i.e., the formation of the penumbra is associated with flux emergence and flux increase of the proto-spot. If two pores merge or if a pore merges with a proto-spot a light bridge is created. This initial light bridge dissolves in the further evolution.

  18. On the formation of a stable penumbra in a region of flux emergence in the Sun

    CERN Document Server

    Murabito, M; Guglielmino, S L; Zuccarello, F

    2016-01-01

    We studied the formation of the first penumbral sector around a pore in the following polarity of the Active Region (AR) NOAA 11490. We used a high spatial, spectral, and temporal resolution data set acquired by the Interferometric BIdimensional Spectrometer operating at the NSO/Dunn Solar Telescope as well as data taken by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory satellite. On the side towards the leading polarity, elongated granules in the photosphere and an arch filament system (AFS) in the chromosphere are present, while the magnetic field shows a sea-serpent configuration, indicating a region of magnetic flux emergence. We found that the formation of a stable penumbra in the following polarity of the AR begins in the area facing the opposite polarity located below the AFS in the flux emergence region, differently from what found by Schlichenmaier and colleaguestbf. Moreover, during the formation of the first penumbral sector, the area characterized by magnetic flux dens...

  19. On the origin of reverse polarity patches found by Hinode in sunspot penumbrae

    CERN Document Server

    Almeida, J Sanchez

    2009-01-01

    The satellite Hinode has recently revealed penumbral structures with a magnetic polarity opposite to the main sunspot polarity. They may be a direct confirmation of magnetic field lines and mass flows returning to the solar interior throughout the penumbra, a configuration previously inferred from interpretation of observed Stokes profile asymmetries. The paper points out the relationship between the reverse polarity features found by Hinode, and the model Micro-Structured Magnetic Atmospheres (MISMAs) proposed for sunspots. We show how the existing model MISMAs produce strongly redshifted reverse polarity structures as found by Hinode. Ad hoc model MISMAs also explain the asymmetric Stokes profiles observed by Hinode. The same modeling may be consistent with magnetograms of dark cored penumbral filaments if the dark cores are associated with the reverse polarity. Such hypothetical relationship will show up only in the far red wings of the spectral lines.

  20. Differential Temporal Evolution Patterns in Brain Temperature in Different Ischemic Tissues in a Monkey Model of Middle Cerebral Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Zhihua Sun

    2012-01-01

    Full Text Available Brain temperature is elevated in acute ischemic stroke, especially in the ischemic penumbra (IP. We attempted to investigate the dynamic evolution of brain temperature in different ischemic regions in a monkey model of middle cerebral artery occlusion. The brain temperature of different ischemic regions was measured with proton magnetic resonance spectroscopy (1H MRS, and the evolution processes of brain temperature were compared among different ischemic regions. We found that the normal (baseline brain temperature of the monkey brain was 37.16°C. In the artery occlusion stage, the mean brain temperature of ischemic tissue was 1.16°C higher than the baseline; however, this increase was region dependent, with 1.72°C in the IP, 1.08°C in the infarct core, and 0.62°C in the oligemic region. After recanalization, the brain temperature of the infarct core showed a pattern of an initial decrease accompanied by a subsequent increase. However, the brain temperature of the IP and oligemic region showed a monotonously and slowly decreased pattern. Our study suggests that in vivo measurement of brain temperature could help to identify whether ischemic tissue survives.

  1. Acute Ischemic Stroke and Transient Ischemic Attack

    OpenAIRE

    Staykov, Dimitre; Schwab, Stefan

    2014-01-01

    This short review focuses on recent practically relevant studies in stroke treatment and prevention and discusses their implications on clinical practice and future research, including 3 shortly published randomized controlled trials investigating interventional treatment in acute ischemic stroke (The Interventional Management of Stroke phase III trial [IMS III], Synthesis Expansion: A Randomized Controlled Trial on Intra-Arterial Versus Intravenous Thrombolysis in Acute Ischemic Stroke, and ...

  2. Electroacupuncture enhances rehabilitation through miR-181b targeting PirB after ischemic stroke.

    Science.gov (United States)

    Deng, Bin; Bai, Fuhai; Zhou, Heng; Zhou, Dandan; Ma, Zhi; Xiong, Lize; Wang, Qiang

    2016-12-14

    Recent studies have demonstrated microRNAs (miRNAs) and proteins are beneficial to axon regeneration, which may be involved in Electroacupuncture (EA) therapy against stroke. In this study, we aimed to determine the pivotal role of PirB in EA-produced rehabilitation against ischemic stroke; and to screen and investigate the potential miRNAs directly regulating PirB expression. The results showed EA treatment enhanced axon regeneration and new projections from the corticospinal tract at 28 d after cerebral ischemic reperfusion injury of rats. Then, we found EA decreased pirb mRNA and PirB protein expression in the penumbra within 28 days after reperfusion. The reduction of PirB expression facilitated neurite outgrowth after oxygen-glucose deprivation injury. The miRNA microarray showed the level of twenty kinds of miRNAs changed in the penumbra after EA administration. The bioinformatics study and luciferase assay verified miR-181b directly regulated pirb mRNA expression. EA increased miR-181b levels in the penumbras, and improved neurobehavioral function rehabilitation through miR-181b direct targeting of pirb mRNA to regulate the expression of PirB, RhoA and GAP43. In conclusion, we provide the first evidence that EA enhances rehabilitation against stroke by regulating epigenetic changes to directly act on its targets, such as the miR-181b/PirB/RhoA/GAP43 axis, which is a novel mechanism of EA therapy.

  3. Variations of CHI3L1, levels of the encoded glycoprotein YKL-40 and prediction of fatal and non-fatal ischemic stroke

    DEFF Research Database (Denmark)

    Rathcke, Camilla Noelle; Thomsen, Stine Brinkloev; Linneberg, Allan

    2012-01-01

    levels and all-cause and cardiovascular mortality and first-time incidence of myocardial infarction, ischemic heart disease (IHD) and stroke. METHODOLOGY/PRINCIPAL FINDINGS: 12 SNPs of CHI3L1 were genotyped and serum YKL-40 was measured in 2656 Danes representative of the general population. Median...... follow-up period was 15 (0-16) years. Admission data and deaths were ascertained from registers from the Danish National Board of Health. Fourth quartile YKL-40 levels were associated with an increased mortality risk of ischemic stroke (HR 2.44 (1.01-5.88), p = 0.041) and so were homozygotes of the minor...... allele of rs872129 (HR 9.35 (1.25-69.87, p = 0.022)). Both continuous YKL-40 levels and 4(th) quartile YKL-40 values (>85 ng/ml) were associated with all-cause mortality (HRs 1.22 (95% CI, 1.10-1.35), p85 ng/ml) and rs872129 were associated with an increased mortality risk of ischemic stroke, but high...

  4. Long-Term Treatment with Citicoline Prevents Cognitive Decline and Predicts a Better Quality of Life after a First Ischemic Stroke.

    Science.gov (United States)

    Alvarez-Sabín, Jose; Santamarina, Estevo; Maisterra, Olga; Jacas, Carlos; Molina, Carlos; Quintana, Manuel

    2016-03-16

    Stroke, as the leading cause of physical disability and cognitive impairment, has a very significant impact on patients' quality of life (QoL). The objective of this study is to know the effect of citicoline treatment in Qol and cognitive performance in the long-term in patients with a first ischemic stroke. This is an open-label, randomized, parallel study of citicoline vs. usual treatment. All subjects were selected 6 weeks after suffering a first ischemic stroke and randomized into parallel arms. Neuropsychological evaluation was performed at 1 month, 6 months, 1 year and 2 years after stroke, and QoL was measured using the EuroQoL-5D questionnaire at 2 years. 163 patients were followed during 2 years. The mean age was 67.5 years-old, and 50.9% were women. Age and absence of citicoline treatment were independent predictors of both utility and poor quality of life. Patients with cognitive impairment had a poorer QoL at 2 years (0.55 vs. 0.66 in utility, p = 0.015). Citicoline treatment improved significantly cognitive status during follow-up (p = 0.005). In conclusion, treatment with long-term citicoline is associated with a better QoL and improves cognitive status 2 years after a first ischemic stroke.

  5. Long-Term Treatment with Citicoline Prevents Cognitive Decline and Predicts a Better Quality of Life after a First Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Jose Alvarez-Sabín

    2016-03-01

    Full Text Available Stroke, as the leading cause of physical disability and cognitive impairment, has a very significant impact on patients’ quality of life (QoL. The objective of this study is to know the effect of citicoline treatment in Qol and cognitive performance in the long-term in patients with a first ischemic stroke. This is an open-label, randomized, parallel study of citicoline vs. usual treatment. All subjects were selected 6 weeks after suffering a first ischemic stroke and randomized into parallel arms. Neuropsychological evaluation was performed at 1 month, 6 months, 1 year and 2 years after stroke, and QoL was measured using the EuroQoL-5D questionnaire at 2 years. 163 patients were followed during 2 years. The mean age was 67.5 years-old, and 50.9% were women. Age and absence of citicoline treatment were independent predictors of both utility and poor quality of life. Patients with cognitive impairment had a poorer QoL at 2 years (0.55 vs. 0.66 in utility, p = 0.015. Citicoline treatment improved significantly cognitive status during follow-up (p = 0.005. In conclusion, treatment with long-term citicoline is associated with a better QoL and improves cognitive status 2 years after a first ischemic stroke.

  6. 短暂性脑缺血发作早期卒中风险预测方法的研究进展%Research Development of Methods Predicting Early Risks of Stroke in Patients with Transient Ischemic Attack

    Institute of Scientific and Technical Information of China (English)

    冷昕祎; 王伊龙; 王拥军

    2011-01-01

    Transient ischemic attack (TIA) is a common cerebrovascular disease, which bears high risks of early stroke after onset. Recently, there emerged several methods predicting early risks of stroke in TIA patients. In order to evaluate stroke risks more accurately, and so as to promote the individualized management and treatment of TIA patients, we reviewed the research development of stroke risk predicting methods of TIA patients in the past a few years.%短暂性脑缺血发作(transient ischemic attack,TIA)是一种常见的脑血管病,患者发病后早期卒中风险较高.近年来出现了一些TIA患者早期卒中风险预测的方法.为了更好地预测TIA患者的早期卒中风险,从而对患者进行分层管理和治疗,本文对TIA早期卒中风险预测方法的研究进展进行了回顾.

  7. Reliability of visual assessment of non-contrast CT, CT angiography source images and CT perfusion in patients with suspected ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Tom van Seeters

    Full Text Available BACKGROUND AND PURPOSE: Good reliability of methods to assess the extent of ischemia in acute stroke is important for implementation in clinical practice, especially between observers with varying experience. Our aim was to determine inter- and intra-observer reliability of the 1/3 middle cerebral artery (MCA rule and the Alberta Stroke Program Early CT Score (ASPECTS for different CT modalities in patients suspected of acute ischemic stroke. METHODS: We prospectively included 105 patients with acute neurological deficit due to suspected acute ischemic stroke within 9 hours after symptom onset. All patients underwent non-contrast CT, CT perfusion and CT angiography on admission. All images were evaluated twice for presence of ischemia, ischemia with >1/3 MCA involvement, and ASPECTS. Four observers evaluated twenty scans twice for intra-observer agreement. We used kappa statistics and intraclass correlation coefficient to calculate agreement. RESULTS: Inter-observer agreement for the 1/3 MCA rule and ASPECTS was fair to good for non-contrast CT, poor to good for CT angiography source images, but excellent for all CT perfusion maps (cerebral blood volume, mean transit time, and predicted penumbra and infarct maps. Intra-observer agreement for the 1/3 MCA rule and ASPECTS was poor to good for non-contrast CT, fair to moderate for CT angiography source images, and good to excellent for all CT perfusion maps. CONCLUSION: Between observers with a different level of experience, agreement on the radiological diagnosis of cerebral ischemia is much better for CT perfusion than for non-contrast CT and CT angiography source images, and therefore CT perfusion is a very reliable addition to standard stroke imaging.

  8. The CHADS2 and CHA2DS2-VASc scores predict adverse vascular function, ischemic stroke and cardiovascular death in high-risk patients without atrial fibrillation: role of incorporating PR prolongation.

    Science.gov (United States)

    Chan, Yap-Hang; Yiu, Kai-Hang; Lau, Kui-Kai; Yiu, Yuen-Fung; Li, Sheung-Wai; Lam, Tai-Hing; Lau, Chu-Pak; Siu, Chung-Wah; Tse, Hung-Fat

    2014-12-01

    To investigate whether the CHADS2 and CHA2DS2-VASc scores have clinical utility for prediction of adverse vascular function and vascular dysfunction-mediated incident cardiovascular (CV) events among high-risk patients without atrial fibrillation (AF), and the additional value of incorporating PR prolongation to the scores. We analyzed 579 high-risk CV outpatients without clinical AF in a prospective cohort for new-onset ischemic stroke, myocardial infarction (MI), congestive heart failure (CHF), and CV death. Brachial flow-mediated dilation (FMD) and nitroglycerin-mediated dilatation (NMD), carotid intima-media thickness (IMT) and pulse wave velocity (PWV) were determined. Baseline CHADS2 score was associated with lower FMD (Pearson r = -0.16, P PR prolongation, the CHA2DS2-VASc-PR score achieved the highest C-Statistic for CV death prediction (0.70, P PR prolongation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Leakage-Penumbra effect in intensity modulated radiation therapy step-and-shoot dose delivery

    Institute of Scientific and Technical Information of China (English)

    Grigor N Grigorov; James CL Chow

    2016-01-01

    AIM: To study the leakage-penumbra(LP) effect with a proposed correction method for the step-and-shoot intensity modulated radiation therapy(IMRT).METHODS: Leakage-penumbra dose profiles from 10 randomly selected prostate IMRT plans were studied. The IMRT plans were delivered by a Varian 21 EX linear accelerator equipped with a 120-leaf multileaf collimator(MLC). For each treatment plan created by the Pinnacle3 treatment planning system,a 3-dimensional LP dose distribution generated by 5 coplanar photon beams,starting from 0o with equal separation of 72 o,was investigated. For each photon beam used in the stepand-shoot IMRT plans,the first beam segment was set to have the largest area in the MLC leaf-sequencing,and was equal to the planning target volume(PTV). The overshoot effect(OSE) and the segment positional errors were measured using a solid water phantom with Kodak(TL and X-OMAT V) radiographic films. Film dosimetric analysis and calibration were carried out using a film scanner(Vidar VXR-16). The LP dose profiles were determined by eliminating the OSE and segment positional errors with specific individual irradiations. RESULTS: A non-uniformly distributed leaf LP dose ranging from 3% to 5% of the beam dose was measured in clinical IMRT beams. An overdose at the gap between neighboring segments,represented as dose peaks of up to 10% of the total BP,was measured. The LP effect increased the dose to the PTV and surrounding critical tissues. In addition,the effectdepends on the number of beams and segments for each beam. Segment positional error was less than the maximum tolerance of 1 mm under a dose rate of 600 monitor units per minute in the treatment plans. The OSE varying with the dose rate was observed in all photon beams,and the effect increased from 1 to 1.3 Gy per treatment of the rectal intersection. As the dosimetric impacts from the LP effect and OSE may increase the rectal post-radiation effects,a correction of LP was proposed and demonstrated for

  10. Measurement of Nutritional Status Using Body Mass Index, Waist-to-Hip Ratio, and Waist Circumference to Predict Treatment Outcome in Females and Males with Acute First-Ever Ischemic Stroke.

    Science.gov (United States)

    Bembenek, Jan Paweł; Karlinski, Michał; Niewada, Maciej; Kurkowska-Jastrzębska, Iwona; Członkowska, Anna

    2017-09-08

    We aimed to investigate whether increased waist-to-hip ratio (WHR), waist circumference (WC), or improper body mass index (BMI) may differently predict short-term outcomes in females and males with first-ever acute ischemic stroke. This was a retrospective study of consecutive patients (1109 females and 939 males) admitted for first-ever ischemic stroke between 2003 and 2015. Data were collected in a detailed hospital stroke registry. BMI of 18.5-24.9 kg/m(2) and gender-specific normal values of WHC and WC were used as references for comparisons. Logistic regression was used to calculate the odds of in-hospital death or being dead or dependent at discharge, adjusted for patients' age and prestroke disability. In both sexes a high WHR increased the odds of death or dependency at discharge (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.05-3.08 for females and 1.43; 95% CI, 1.00-2.04 for males), but not in-hospital death alone. Increased WC was significantly associated with lower odds of either death or death and dependency at discharge in females only (OR, .36; 95% CI, .22-.58 and .69; 95% CI, .48-.97, respectively). BMI did not show any clear predictive value in either sex. Our findings suggest that being overweight measured with WC is a strong predictor of good outcome in women but not in men. The WHR less consistently predicts stroke outcome, as it is not associated with death at discharge alone; however, the WHR seems to be of similar clinical relevance in both genders. BMI seems to have the least clinical value in predicting stroke outcome in both genders. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  11. Coupling of the magnetic field and gas flows inferred from the net circular polarization in a sunspot penumbra

    OpenAIRE

    2015-01-01

    We analyze penumbral fine structure using high-resolution spectropolarimetric data obtained by the Solar Optical Telescope on board the Hinode satellite. The spatial correlation between the net circular polarization (NCP) and Evershed flow is investigated in detail. Here we obtain that negative NCP structures are correlated with the Evershed flow channels in the limb-side penumbra, and that negative NCP or depressions of positive NCP are associated with the Evershed flow channels in the disk ...

  12. On the Formation of Penumbrae as Observed with the German VTT, SOHO/MDI, and SDO/HMI

    CERN Document Server

    Schlichenmaier, Rolf; Gonzalez, Nazaret Bello

    2011-01-01

    Solar magnetic fields are generated in the solar interior and pop up at the solar surface to form active regions. As the magnetic field appears on the surface, it forms various structures like small magnetic elements, pores, and sunspots. The nature of these formation processes is largely unknown. In this contribution we elaborate on the formation of sunspots and particularly on the formation of penumbrae. We report on observations that we obtained at the German VTT on July 4, 2009 on the formation of the spot in AR 11024. This data set is accomplished with data from SOHO/MDI which offers an entire time coverage. Moreover, the evolution of AR 11024 is compared with a particular event of penumbra formation in AR 11124 around November 13, 2010, using intensity images from SDO/HMI. We conclude that two processes contribute to the increase of the magnetic flux of a sunspot: (1) merging pores, and (2) emerging bipoles of which the spot polarity migrates towards and merges with the spot. As the penumbra forms the a...

  13. Coupling of the magnetic field and gas flows in sunspot penumbra inferred from the Hinode/SOT observation

    Science.gov (United States)

    Ichimoto, Kiyoshi; Shaltout, Abdelrazek Mohammed

    2012-07-01

    Sunspot penumbrae has been an enigmatic region that consists of fine scale filamentary structures harboring conspicuous gas flows known as the Evershed flow in the base of photosphere and the inverse-Evershed flow in higher layer. Recent high resolution observations including those by Hinode/SOT revealed that the penumbral magnetic field is highly fluctuating in its strength and inclination in space, and the geometry is called as interlocking comb structure. There is a strong coupling of the magnetic field and gas flow, i.e., many observational aspects suggest the origin of the sunspot penumbra as the vigorous thermal-convection of plasma under the inclined strong magnetic field of sunspots. However the relation between the magnetic field and gas flow is still an open issue to be settled. A number of observational and theoretical works suggest that the convective hot gas with a large flow speed is associated with a weak field. In this paper, we present an evidence of contradictory relation, i.e., a positive correlation between the field strength and flow velocity in photosphere. The geometry of the inverse-Evershed flow in conjunction with the interlocking magnetic field structure of penumbra is another issue that is not understood. We present an insight on the relation between the magnetic field structure and the inverse-Evershed flow based on the SOT/SP observations.

  14. Upper Chromospheric Magnetic Field of a Sunspot Penumbra: Observations of Fine Structure

    CERN Document Server

    Joshi, J; Solanki, S K; Feller, A; Collados, M; Suárez, D Orozco; Schlichenmaier, R; Franz, M; Balthasar, H; Denker, C; Berkefeld, T; Hofmann, A; Kiess, C; Nicklas, H; Yabar, A Pastor; Rezaei, R; Schmidt, D; Schmidt, W; Sobotka, M; Soltau, D; Staude, J; Strassmeier, K G; Volkmer, R; von der Lühe, O; Waldmann, T

    2016-01-01

    The fine-structure of magnetic field of a sunspot penumbra in the upper chromosphere is to be explored and compared to that in the photosphere. High spatial resolution spectropolarimetric observations were recorded with the 1.5-meter GREGOR telescope using the GREGOR Infrared Spectrograph (GRIS). The observed spectral domain includes the upper chromospheric He I triplet at 1083.0 nm and the photospheric Si I 1082.7 nm and Ca I 1083.3 nm spectral lines. The upper chromospheric magnetic field is obtained by inverting the He I triplet assuming a Milne-Eddington type model atmosphere. A height dependent inversion was applied to the Si I 1082.7 nm and Ca I 1083.3 nm lines to obtain the photospheric magnetic field. We find that the inclination of the magnetic field shows variations in the azimuthal direction both in the photosphere, but also in the upper chromosphere. The chromospheric variations remarkably well coincide with the variations in the inclination of the photospheric field and resemble the well-known sp...

  15. Ischemic postconditioning fails to protect against neonatal cerebral stroke.

    Directory of Open Access Journals (Sweden)

    Pierre-Louis Leger

    Full Text Available The lack of efficient neuroprotective strategies for neonatal stroke could be ascribed to pathogenic ischemic processes differentiating adults and neonates. We explored this hypothesis using a rat model of neonatal ischemia induced by permanent occlusion of the left distal middle cerebral artery combined with 50 min of occlusion of both common carotid arteries (CCA. Postconditioning was performed by repetitive brief release and occlusion (30 s, 1 and/or 5 min of CCA after 50 min of CCA occlusion. Alternative reperfusion was generated by controlled release of the bilateral CCA occlusion. Blood-flow velocities in the left internal carotid artery were measured using color-coded pulsed Doppler ultrasound imaging. Cortical perfusion was measured using laser Doppler. Cerebrovascular vasoreactivity was evaluated after inhalation with the hypercapnic gas or inhaled nitric oxide (NO. Whatever the type of serial mechanical interruptions of blood flow at reperfusion, postconditioning did not reduce infarct volume after 72 hours. A gradual perfusion was found during early re-flow both in the left internal carotid artery and in the cortical penumbra. The absence of acute hyperemia during early CCA re-flow, and the lack of NO-dependent vasoreactivity in P7 rat brain could in part explain the inefficiency of ischemic postconditioning after ischemia-reperfusion.

  16. Apoptosis in rat transient focal cerebral ischemic stroke: clinical implications

    Institute of Scientific and Technical Information of China (English)

    Shoushu Jiao; Jue Wang Gal Hever; Rongzheng Kuang; Jean-Claude Louis; Ella Magal

    2000-01-01

    @@In the early phase of cerebral ischemia, factors threatening neuronal survival in the penumbra include mainly glutamate excitotoxicity, free radical damage and energy failure resulting from recurrent depolarization waves. However, at later times, other mechanisms come into play. The initial ischemic event activates a variety of genetic programs that unfold over the course of hours and days. Both positron emission tomography and magnetic resonance based techniques demonstrate that the development of irretrievable tissue damage is relatively slow, progressing over the course of several days in some cases, and a viable tissue, defined by hemodynamic and metabolic criteria,is still present many hours after stroke in human or in monkey. These findings suggest that the brain can potentially be “rescued” from infarction many hours after onset of ischemia and challenge the widespread notion of an early and short “therapeutic window” (~3-6h). This realization is of critical importance for stroke therapy because most patients reach medical attention at a time when current therapeutic strategies may no longer be effective. Therefore, it would be highly desirable to develop therapeutic interventions that can be instituted many hours after the onset of ischemia. We believe that addressing the mechanisms of delayed cell death is key to a successful therapy. The studies presented here were designed to document the potential contribution of apoptosis to ischemia induced neuronal death. We will discuss the morphological, biochemical and pharmacological evidence for apoptosis in the ischemic stroke.

  17. Suppression of Etk/Bmx protects against ischemic brain injury.

    Science.gov (United States)

    Chen, Kai-Yun; Wu, Chung-Che; Chang, Cheng-Fu; Chen, Yuan-Hao; Chiu, Wen-Ta; Lou, Ya-Hsin; Chen, Yen-Hua; Shih, Hsiu-Ming; Chiang, Yung-Hsiao

    2012-01-01

    Etk/Bmx (epithelial and endothelial tyrosine kinase, also known as BMX), a member of the Tec (tyrosine kinase expressed in hepatocellular carcinoma) family of protein-tyrosine kinases, is an important regulator of signal transduction for the activation of cell growth, differentiation, and development. We have previously reported that activation of Etk leads to apoptosis in MDA-MB-468 cells. The purpose of this study was to examine the role of Etk in neuronal injury induced by H(2)O(2) or ischemia. Using Western blot analysis and immunohistochemistry, we found that treatment with H(2)O(2) significantly enhanced phosphorylation of Etk and its downstream signaling molecule Stat1 in primary cortical neurons. Inhibiting Etk activity by LFM-A13 or knocking down Etk expression by a specific shRNA increased the survival of primary cortical neurons. Similarly, at 1 day after a 60-min middle cerebral artery occlusion (MCAo) in adult rats, both phosphorylated Etk and Stat1 were coexpressed with apoptotic markers in neurons in the penumbra. Pretreatment with LFM-A13 or an adenoviral vector encoding the kinase deletion mutant Etkk attenuated caspase-3 activity and infarct volume in ischemic brain. All together, our data suggest that Etk is activated after neuronal injury. Suppressing Etk activity protects against neurodegeneration in ischemic brain.

  18. Modifiable risk factors for ischemic stroke

    Directory of Open Access Journals (Sweden)

    Alexandros Gianoulakis

    2010-07-01

    atherosclerosis. Furthermore, blood diseases and mainly sickle-cell disease is responsible for ischemic stroke because the progressive narrowing of blood vessels prevents oxygen from reaching the brain and other tissues.Conclusions: As it is supported by published evidence, the main modifiable risk factors for stroke are hypertension, atrial fibrillation, diabetes mellitus, carotid stenosis, smoking and sickle-cell disease. Taking into account that these factors are modifiable and consequently predictable, the organization of educational programs in individuals of high risk is a matter of great importance.

  19. The impact of sleep-disordered breathing on early functional recovery in ischemic stroke

    Directory of Open Access Journals (Sweden)

    G. M. Lutokhin

    2017-01-01

    Full Text Available The rehabilitation potential in ischemic stroke depends both on the localization and size of cerebral infarction and on many other factors ensuring the restoration of neuron function in the ischemic penumbra. Sleep-disordered breathing (SDB appears as intermittent episodes of apnea and hypopnea, which are accompanied by hypoxemia and tissue hypoxia, and may slow early functional recovery in patients.Objective: to evaluate the impact of SDB on early neurological recovery in patients with ischemic stroke and to identify predictors of unfavorable functional outcome.Patients and methods. A total of 56 patients (24 men, 32 women; mean age 62±15 years with ischemic stroke were examined. All the patients underwent brain magnetic resonance imaging. Neurological deficit was assessed using the National Institutes of Health Stroke Scale (NIHSS, modified Rankin Scale (mRS on admission and at 3 weeks. To identify SDB, cardiorespiratory monitoring was performed on 2–5 days after the onset of the disease. The total number of episodes of SDB, apnea, hypopnea, apnea-hypopnea index (AHI, hypoxemia index, and the total time with arterial oxygen saturation < 90% (desaturation time < 90% were recorded. Results and discussion. At baseline, the median NIHSS score was 6 (range 4–10 and the median mRS score was 3 (range 2–5. After 3 weeks, the median NIHSS score was 3 (range 1.5–5 and the median mRS score was 1 (range 0–3. According to the degree of achieved functional independence, the patients were divided into 2 groups: 1 40 functionally independent patients (a mRS score of ≤2; 2 16 patients in need of assistance/care (a mRS score of ≥3. The groups were matched for age, sex, localization of cerebral infarction, degree of cerebral atherosclerosis, and incidence of cardiac pathology. At the same time, at baseline Group 2 had a more severity of neurological deficit (p=0.001 and respiratory disorders (p<0.04 and more frequently large and

  20. Morbidity predictors in ischemic stroke

    Directory of Open Access Journals (Sweden)

    Panicker J

    2003-01-01

    Full Text Available Background: Although ischemic CVA is one of the leading causes for death and disability, parameters for predicting long-term outcome in such patients have not been clearly delineated, especially in the Indian context. Methods: A prospective hospital-based study of 105 patients of ischemic stroke, focal neurological deficits and functional score was assessed and the C-reactive protein level (CRP was measured. A follow-up was done at 5 days and at 6 months and outcome variable was the functional status at 6 months using Barthel Index of Activities of Daily Living. Accordingly, patients were grouped into 3 - Barthel Index < 41: Severely disabled, Barthel Index 41-60: Moderately disabled and Barthel Index > 60: Mildly disabled. Results: At admission, if upper limb power was less than Medical Research Council (MRC grade 4, or aphasia was present or CRP assay was positive, then at 6 months, these patients most likely belonged to the severely disabled group. If upper limb or lower limb power was greater than MRC grade 3 or there was no aphasia or conjugate gaze deviation or CRP assay was negative, these patients most likely belonged to the mildly disabled group at 6 months. Follow-up rate was 86%. Conclusion: Patients can be stratified according to the predicted prognosis. The treatment and rehabilitation can be properly planned and strictly adhered to in patients predicted to have worse prognosis.

  1. Lubiprostone induced ischemic colitis.

    Science.gov (United States)

    Sherid, Muhammed; Sifuentes, Humberto; Samo, Salih; Deepak, Parakkal; Sridhar, Subbaramiah

    2013-01-14

    Ischemic colitis accounts for 6%-18% of the causes of acute lower gastrointestinal bleeding. It is often multifactorial and more commonly encountered in the elderly. Several medications have been implicated in the development of colonic ischemia. We report a case of a 54-year old woman who presented with a two-hour history of nausea, vomiting, abdominal pain, and bloody stool. The patient had recently used lubiprostone with close temporal relationship between the increase in the dose and her symptoms of rectal bleeding. The radiologic, colonoscopic and histopathologic findings were all consistent with ischemic colitis. Her condition improved without any serious complications after the cessation of lubiprostone. This is the first reported case of ischemic colitis with a clear relationship with lubiprostone (Naranjo score of 10). Clinical vigilance for ischemic colitis is recommended for patients receiving lubiprostone who are presenting with abdominal pain and rectal bleeding.

  2. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an ... a short time. The only difference between a stroke and TIA is that with TIA the blockage ...

  3. Preterm Hypoxic Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Krishna G Gopagondanahalli

    2016-10-01

    Full Text Available Hypoxic ischemic encephalopathy (HIE is a recognizable and defined clinical syndrome in term infants that results from a severe or prolonged hypoxic ischemic episode before or during birth. However, in the preterm infant, defining hypoxic ischemic injury, its clinical course, monitoring and outcomes remains complex. Few studies examine preterm HIE, and these are heterogeneous, with variable inclusion criteria and outcomes reported. We examine the available evidence that implies that the incidence of hypoxic ischemic insult in preterm infants is probably higher than recognized, and follows a more complex clinical course, with higher rates of adverse neurological outcomes, compared to term infants. This review aims to elucidate the causes and consequences of preterm hypoxia ischemia, the subsequent clinical encephalopathy syndrome, diagnostic tools and outcomes. Finally, we suggest a uniform definition for preterm HIE that may help in identifying infants most at risk of adverse outcomes and amenable to neuroprotective therapies.

  4. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an ... a short time. The only difference between a stroke and TIA is that with TIA the blockage ...

  5. Acute ischemic cerebral attack

    OpenAIRE

    Franco-Garcia Samir; Barreiro-Pinto Belis

    2010-01-01

    The decrease of the cerebral blood flow below the threshold of autoregulation led to changes of cerebral ischemia and necrosis that traduce in signs and symtoms of focal neurologic dysfunction called acute cerebrovascular symdrome (ACS) or stroke. Two big groups according to its etiology are included in this category the hemorragic that constitue a 20% and the ischemic a 80% of cases. Great interest has wom the ischemic ACS because of its high social burden, being the third cause of no violen...

  6. Rescue strategy for acute carotid stent thrombosis during carotid stenting with distal filter protection using forced arterial suction thrombectomy with a reperfusion catheter of the Penumbra System: a technical note.

    Science.gov (United States)

    Kim, Yong-Won; Kang, Dong-Hun; Hwang, Jeong-Hyun; Park, Jaechan; Hwang, Yang-Ha; Kim, Yong-Sun

    2013-08-01

    Among the procedural complications related to carotid artery stenting (CAS), internal carotid artery (ICA) flow arrest is one of the most drastic complications, as it can cause major ischemic stroke. Acute carotid stent thrombosis (ACST) is a rare etiology of ICA flow arrest during carotid artery stenting with distal filter protection, but the most devastating. Moreover, no definitive management strategy has been established so far for treating ACST. We introduce a rescue management strategy for differential diagnosis of ICA flow arrest and for recanalization of ACST with a simple endovascular mechanical thrombectomy technique. In three cases of ICA flow arrest caused by ACST, selective angiography with a 1.7 F microcatheter provided confirmative diagnosis. Recanalization was then achieved with a Penumbra System (PS) reperfusion catheter using the forced arterial suction thrombectomy (FAST) technique. Successful recanalization with a Thrombolysis In Cerebral Infarction score of 3 was achieved for all three patients. Recanalization was confirmed with follow-up angiography at least 24 h after the procedure. No complications associated with this technique occurred. Based on our preliminary experiences, selective microangiography can be helpful for rapid diagnosis of ACST, and the present mechanical thrombectomy technique, using a modification of the PS, can play a role in adjuvant management or as a last resort for the treatment of ACST during CAS.

  7. C5a receptor (CD88) inhibition improves hypothermia-induced neuroprotection in an in vitro ischemic model.

    Science.gov (United States)

    Thundyil, John; Pavlovski, Dale; Hsieh, Yu-Hsuan; Gelderblom, Mathias; Magnus, Tim; Fairlie, David P; Arumugam, Thiruma V

    2012-03-01

    The concept of 'salvageble penumbra' has prompted both scientists and physicians to explore various neuroprotective approaches that could be beneficial during stroke therapy. Unfortunately, most of them have proved ineffective in targeting multiple cellular death cascades incited within the ischemic penumbra. Hypothermia has been shown to be capable of addressing this problem to some extent. Although many studies have shown that hypothermia targets several cellular processes, its effects on innate immune receptor-mediated apoptotic death still remain unclear. Moreover, whether inhibiting the signaling of innate immune receptors like complement anaphylatoxin C5a receptor (CD88) plays a role in this hypothermic neuroprotection still need to be deciphered. Using various types of ischemic insults in different neuronal cells, we confirm that hypothermia does indeed attenuate apoptotic neuronal cell death in vitro and this effect can be further enhanced by pharmacologically blocking or knocking out CD88. Thus, our study raises a promising therapeutic possibility of adding CD88 antagonists along with hypothermia to improve stroke outcomes.

  8. Highly efficient differentiation of neural precursors from human embryonic stem cells and benefits of transplantation after ischemic stroke in mice.

    Science.gov (United States)

    Drury-Stewart, Danielle; Song, Mingke; Mohamad, Osama; Guo, Ying; Gu, Xiaohuan; Chen, Dongdong; Wei, Ling

    2013-08-08

    Ischemic stroke is a leading cause of death and disability, but treatment options are severely limited. Cell therapy offers an attractive strategy for regenerating lost tissues and enhancing the endogenous healing process. In this study, we investigated the use of human embryonic stem cell-derived neural precursors as a cell therapy in a murine stroke model. Neural precursors were derived from human embryonic stem cells by using a fully adherent SMAD inhibition protocol employing small molecules. The efficiency of neural induction and the ability of these cells to further differentiate into neurons were assessed by using immunocytochemistry. Whole-cell patch-clamp recording was used to demonstrate the electrophysiological activity of human embryonic stem cell-derived neurons. Neural precursors were transplanted into the core and penumbra regions of a focal ischemic stroke in the barrel cortex of mice. Animals received injections of bromodeoxyuridine to track regeneration. Neural differentiation of the transplanted cells and regenerative markers were measured by using immunohistochemistry. The adhesive removal test was used to determine functional improvement after stroke and intervention. After 11 days of neural induction by using the small-molecule protocol, over 95% of human embryonic stem-derived cells expressed at least one neural marker. Further in vitro differentiation yielded cells that stained for mature neuronal markers and exhibited high-amplitude, repetitive action potentials in response to depolarization. Neuronal differentiation also occurred after transplantation into the ischemic cortex. A greater level of bromodeoxyuridine co-localization with neurons was observed in the penumbra region of animals receiving cell transplantation. Transplantation also improved sensory recovery in transplant animals over that in control animals. Human embryonic stem cell-derived neural precursors derived by using a highly efficient small-molecule SMAD inhibition

  9. Penumbra pattern assessment in acute stroke patients: comparison of quantitative and non-quantitative methods in whole brain CT perfusion.

    Directory of Open Access Journals (Sweden)

    Kolja M Thierfelder

    Full Text Available BACKGROUND AND PURPOSE: While penumbra assessment has become an important part of the clinical decision making for acute stroke patients, there is a lack of studies measuring the reliability and reproducibility of defined assessment techniques in the clinical setting. Our aim was to determine reliability and reproducibility of different types of three-dimensional penumbra assessment methods in stroke patients who underwent whole brain CT perfusion imaging (WB-CTP. MATERIALS AND METHODS: We included 29 patients with a confirmed MCA infarction who underwent initial WB-CTP with a scan coverage of 100 mm in the z-axis. Two blinded and experienced readers assessed the flow-volume-mismatch twice and in two quantitative ways: Performing a volumetric mismatch analysis using OsiriX imaging software (MM(VOL and visual estimation of mismatch (MM(EST. Complementarily, the semiquantitative Alberta Stroke Programme Early CT Score for CT perfusion was used to define mismatch (MM(ASPECTS. A favorable penumbral pattern was defined by a mismatch of ≥ 30% in combination with a cerebral blood flow deficit of ≤ 90 ml and an MM(ASPECTS score of ≥ 1, respectively. Inter- and intrareader agreement was determined by Kappa-values and ICCs. RESULTS: Overall, MM(VOL showed considerably higher inter-/intrareader agreement (ICCs: 0.751/0.843 compared to MM(EST (0.292/0.749. In the subgroup of large (≥ 50 mL perfusion deficits, inter- and intrareader agreement of MM(VOL was excellent (ICCs: 0.961/0.942, while MM(EST interreader agreement was poor (0.415 and intrareader agreement was good (0.919. With respect to penumbra classification, MM(VOL showed the highest agreement (interreader agreement: 25 agreements/4 non-agreements/κ: 0.595; intrareader agreement 27/2/0.833, followed by MM(EST (22/7/0.471; 23/6/0.577, and MM(ASPECTS (18/11/0.133; 21/8/0.340. CONCLUSION: The evaluated approach of volumetric mismatch assessment is superior to pure visual and ASPECTS penumbra

  10. Experimental measurement of radiological penumbra associated with intermediate energy x-rays (1 MV) and small radiosurgery field sizes.

    Science.gov (United States)

    Keller, Brian M; Beachey, David J; Pignol, Jean-Philippe

    2007-10-01

    Stereotactic radiosurgery is used to treat intracranial lesions with a high degree of accuracy. At the present time, x-ray energies at or above Co-60 gamma rays are used. Previous Monte Carlo simulations have demonstrated that intermediate energy x-ray photons or IEPs (defined to be photons in the energy range of 0.2-1.2 MeV), combined with small field sizes, produce a reduced radiological penumbra leading to a sharper dose gradient, improved dose homogeneity and sparing of critical anatomy adjacent to the target volume. This hypothesis is based on the fact that, for small x-ray fields, a dose outside the treatment volume is dictated mainly by the range of electrons set into motion by x-ray photons. The purpose of this work is: (1) to produce intermediate energy x rays using a detuned medical linear accelerator, (2) to characterize the energy of this beam, (3) to measure the radiological penumbra for IEPs and small fields to compare with that produced by 6 MV x rays or Co-60, and (4) to compare these experimental measurements with Monte Carlo computer simulations. The maximum photon energy of our IEP x-ray spectrum was measured to be 1.2 MeV. Gafchromic EBT films (ISP Technologies, Wayne, NJ) were irradiated and read using a novel digital microscopy imaging system with high spatial resolution. Under identical irradiation conditions the measured radiological penumbra widths (80%-20% distance), for field sizes ranging from 0.3 x 0.3 to 4.0 x 4.0 cm2, varied from 0.3-0.77 mm (1.2 MV) and from 1.1-2.1 mm (6 MV). Even more dramatic were the differences found when comparing the 90%-10% or the 95%-5% widths, which are in fact more significant in radiotherapy. Monte Carlo simulations agreed well with the experimental findings. The reduction in radiological penumbra could be substantial for specific clinical situations such as in the treatment of an ocular melanoma abutting the macula or for the treatment of functional disorders such as trigeminal neuralgia (a nonlethal

  11. Changes of resting cerebral activities in subacute ischemic stroke patients

    Directory of Open Access Journals (Sweden)

    Ping Wu

    2015-01-01

    Full Text Available This study aimed to detect the difference in resting cerebral activities between ischemic stroke patients and healthy participants, define the abnormal site, and provide new evidence for pathological mechanisms, clinical diagnosis, prognosis prediction and efficacy evaluation of ischemic stroke. At present, the majority of functional magnetic resonance imaging studies focus on the motor dysfunction and the acute stage of ischemic stroke. This study recruited 15 right-handed ischemic stroke patients at subacute stage (15 days to 11.5 weeks and 15 age-matched healthy participants. A resting-state functional magnetic resonance imaging scan was performed on each subject to detect cerebral activity. Regional homogeneity analysis was used to investigate the difference in cerebral activities between ischemic stroke patients and healthy participants. The results showed that the ischemic stroke patients had lower regional homogeneity in anterior cingulate and left cerebrum and higher regional homogeneity in cerebellum, left precuneus and left frontal lobe, compared with healthy participants. The experimental findings demonstrate that the areas in which regional homogeneity was different between ischemic stroke patients and healthy participants are in the cerebellum, left precuneus, left triangle inferior frontal gyrus, left inferior temporal gyrus and anterior cingulate. These locations, related to the motor, sensory and emotion areas, are likely potential targets for the neural regeneration of subacute ischemic stroke patients.

  12. Changes of resting cerebral activities in subacute ischemic stroke patients

    Institute of Scientific and Technical Information of China (English)

    Ping Wu; Fang Zeng; Yong-xin Li; Bai-li Yu; Li-hua Qiu; Wei Qin; Ji Li; Yu-mei Zhou; Fan-rong Liang

    2015-01-01

    This study aimed to detect the difference in resting cerebral activities between ischemic stroke pa-tients and healthy participants, deifne the abnormal site, and provide new evidence for pathological mechanisms, clinical diagnosis, prognosis prediction and efifcacy evaluation of ischemic stroke. At present, the majority of functional magnetic resonance imaging studies focus on the motor dysfunc-tion and the acute stage of ischemic stroke. This study recruited 15 right-handed ischemic stroke patients at subacute stage (15 days to 11.5 weeks) and 15 age-matched healthy participants. A rest-ing-state functional magnetic resonance imaging scan was performed on each subject to detect cerebral activity. Regional homogeneity analysis was used to investigate the difference in cerebral activities between ischemic stroke patients and healthy participants. The results showed that the ischemic stroke patients had lower regional homogeneity in anterior cingulate and left cerebrum and higher regional homogeneity in cerebellum, left precuneus and left frontal lobe, compared with healthy participants. The experimental ifndings demonstrate that the areas in which regional homogeneity was different between ischemic stroke patients and healthy participants are in the cerebellum, left precuneus, left triangle inferior frontal gyrus, left inferior temporal gyrus and anterior cingulate. These locations, related to the motor, sensory and emotion areas, are likely po-tential targets for the neural regeneration of subacute ischemic stroke patients.

  13. Promotor polymorphisms in leukotriene C4 synthase and risk of ischemic cerebrovascular disease

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Sillesen, H.

    2008-01-01

    genotyped 10 592 individuals from the Danish general population, the Copenhagen City Heart Study. During 24 years of follow-up, 557 individuals developed ischemic cerebrovascular disease. The allele frequency was 0.07 for -1072 A and 0.29 for -444 C. Cumulative incidence for ischemic cerebrovascular disease...... atherosclerosis, or with levels of platelets and coagulation factors. CONCLUSIONS: Leukotriene C(4) synthase -1072 AA genotype predict increased risk, whereas -444 CC genotype predict decreased risk of ischemic cerebrovascular disease....

  14. [Ischemic heart disease].

    Science.gov (United States)

    Yamamuro, Megumi; Ogawa, Hisao

    2009-04-01

    It has been reported that antihypertensive therapy reduces the risk of ischemic heart disease. Except for the antihypertensive effects, the angiotensin converting enzyme (ACE) inhibitors are proved to be very effective in primary and secondary event onset prophylaxis by many clinical trials. The angiotensin II receptor antagonists (ARBs) used briskly in recent years inhibits angiotensin II type 1 receptor alternatively. Although ARBs protect organs, especially blood vessel, heart, brain and kidney in sites of pharmacology, ARBs are still not much as effective results as ACE inhibitors for the patients with ischemic heart disease, by many clinical trials.

  15. An update on brain imaging in transient ischemic attack.

    Science.gov (United States)

    Souillard-Scemama, R; Tisserand, M; Calvet, D; Jumadilova, D; Lion, S; Turc, G; Edjlali, M; Mellerio, C; Lamy, C; Naggara, O; Meder, J-F; Oppenheim, C

    2015-02-01

    Neuroimaging is critical in the evaluation of patients with transient ischemic attack (TIA) and MRI is the recommended modality to image an ischemic lesion. The presence of a diffusion (DWI) lesion in a patient with transient neurological symptoms confirms the vascular origin of the deficit and is predictive of a high risk of stroke. Refinement of MR studies including high resolution DWI and perfusion imaging using either MRI or CT further improve the detection of ischemic lesions. Rapid etiological work-up includes non-invasive imaging of cervical and intracranial arteries to search for symptomatic stenosis/occlusion associated with an increased risk of stroke.

  16. A pharmacological screening approach for discovery of neuroprotective compounds in ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Simret Beraki

    Full Text Available With the availability and ease of small molecule production and design continuing to improve, robust, high-throughput methods for screening are increasingly necessary to find pharmacologically relevant compounds amongst the masses of potential candidates. Here, we demonstrate that a primary oxygen glucose deprivation assay in primary cortical neurons followed by secondary assays (i.e. post-treatment protocol in organotypic hippocampal slice cultures and cortical neurons can be used as a robust screen to identify neuroprotective compounds with potential therapeutic efficacy. In our screen about 50% of the compounds in a library of pharmacologically active compounds displayed some degree of neuroprotective activity if tested in a pre-treatment toxicity assay but just a few of these compounds, including Carbenoxolone, remained active when tested in a post-treatment protocol. When further examined, Carbenoxolone also led to a significant reduction in infarction size and neuronal damage in the ischemic penumbra when administered six hours post middle cerebral artery occlusion in rats. Pharmacological testing of Carbenoxolone-related compounds, acting by inhibition of 11-β-hydroxysteroid dehydrogenase-1 (11β-HSD1, gave rise to similarly potent in vivo neuroprotection. This indicates that the increase of intracellular glucocorticoid levels mediated by 11β-HSD1 may be involved in the mechanism that exacerbates ischemic neuronal cell death, and inhibiting this enzyme could have potential therapeutic value for neuroprotective therapies in ischemic stroke and other neurodegenerative disorders associated with neuronal injury.

  17. Autologous bone marrow mononuclear cells in ischemic cerebrovascular accident paves way for neurorestoration: a case report.

    Science.gov (United States)

    Sharma, Alok; Sane, Hemangi; Nagrajan, Anjana; Gokulchandran, Nandini; Badhe, Prerna; Paranjape, Amruta; Biju, Hema

    2014-01-01

    In response to acute ischemic stroke, large numbers of bone marrow stem cells mobilize spontaneously in peripheral blood that home onto the site of ischemia activating the penumbra. But with chronicity, the numbers of mobilized cells decrease, reducing the degree and rate of recovery. Cellular therapy has been explored as a new avenue to restore the repair process in the chronic stage. A 67-year-old Indian male with a chronic right middle cerebral artery ischemic stroke had residual left hemiparesis despite standard management. Recovery was slow and partial resulting in dependence to carry out activities of daily living. Our aim was to enhance the speed of recovery process by providing an increased number of stem cells to the site of injury. We administered autologous bone marrow mononuclear cells intrathecally alongwith rehabilitation and regular follow up. The striking fact was that the hand functions, which are the most challenging deficits, showed significant recovery. Functional Independence Measure scores and quality of life improved. This could be attributed to the neural tissue restoration. We hypothesize that cell therapy may be safe, novel and appealing treatment for chronic ischemic stroke. Further controlled trials are indicated to advance the concept of Neurorestoration.

  18. Autologous Bone Marrow Mononuclear Cells in Ischemic Cerebrovascular Accident Paves Way for Neurorestoration: A Case Report

    Directory of Open Access Journals (Sweden)

    Alok Sharma

    2014-01-01

    Full Text Available In response to acute ischemic stroke, large numbers of bone marrow stem cells mobilize spontaneously in peripheral blood that home onto the site of ischemia activating the penumbra. But with chronicity, the numbers of mobilized cells decrease, reducing the degree and rate of recovery. Cellular therapy has been explored as a new avenue to restore the repair process in the chronic stage. A 67-year-old Indian male with a chronic right middle cerebral artery ischemic stroke had residual left hemiparesis despite standard management. Recovery was slow and partial resulting in dependence to carry out activities of daily living. Our aim was to enhance the speed of recovery process by providing an increased number of stem cells to the site of injury. We administered autologous bone marrow mononuclear cells intrathecally alongwith rehabilitation and regular follow up. The striking fact was that the hand functions, which are the most challenging deficits, showed significant recovery. Functional Independence Measure scores and quality of life improved. This could be attributed to the neural tissue restoration. We hypothesize that cell therapy may be safe, novel and appealing treatment for chronic ischemic stroke. Further controlled trials are indicated to advance the concept of Neurorestoration.

  19. National trends in utilization and outcomes of endovascular treatment of acute ischemic stroke patients in the mechanical thrombectomy era.

    Science.gov (United States)

    Hassan, Ameer E; Chaudhry, Saqib A; Grigoryan, Mikayel; Tekle, Wondwossen G; Qureshi, Adnan I

    2012-11-01

    Because several new devices for mechanical thrombectomy have become available, the outcomes of patients undergoing endovascular treatment for acute ischemic stroke are expected to improve in the United States. We performed this analysis to evaluate trends in utilization of endovascular treatment and associated rates of death and disability among acute ischemic stroke patients over a 6-year period, including further assessment within age strata. We obtained data for patients admitted to hospitals in the United States from 2004 to 2009 with a primary diagnosis of ischemic stroke using a large national database. We determined the rate and pattern of utilization, and associated in-hospital outcomes of endovascular treatment among ischemic stroke patients and further analyzed trends within age strata. Outcomes were classified as minimal disability, moderate to severe disability, and death based on discharge disposition and compared between 2 time periods: 2004 to 2007 (post-MERCI) and 2008 to 2009 (post-Penumbra) approvals Of the 3,292,842 patients admitted with ischemic stroke, 72,342 (2.2%) received intravenous thrombolytic treatment and 13 799 (0.4%) underwent endovascular treatment. There was a 6-fold increase in patients who underwent endovascular treatment (0.1% of ischemic strokes in 2004 vs 0.6% in 2009; Pacute ischemic stroke patients receiving endovascular treatment over the 6 years and reduction in in-hospital mortality. Our results highlight the need to implement endovascular techniques in a balanced manner across various age groups that also results in the reduction of disability in addition to mortality.

  20. Treadmill Exercise Promotes Neurogenesis in Ischemic Rat Brains via Caveolin-1/VEGF Signaling Pathways.

    Science.gov (United States)

    Zhao, Yun; Pang, Qiongyi; Liu, Meixia; Pan, Jingzi; Xiang, Bingwu; Huang, Tingting; Tu, Fengxia; Liu, Chan; Chen, Xiang

    2017-02-01

    Using a model of middle cerebral artery occlusion (MCAO), we have previously demonstrated that treadmill exercise promotes angiogenesis in the ischemic penumbra through caveolin-1/VEGF signaling pathways. However, the function of caveolin-1/VEGF signaling in neurogenesis after MCAO has not been determined. In this study, we aimed to investigate the potential of treadmill exercise to promote neurogenesis after MCAO and whether caveolin-1/VEGF signaling pathways are involved. After MCAO, rats were subjected to a program of treadmill exercise. Daidzein (a specific inhibitor of caveolin-1 protein expression, 0.4 mg/kg) was used to confirm the effect of caveolin-1/VEGF signaling on exercise-mediated neurogenesis. We found that the total protein expression of both caveolin-1 and VEGF was increased by exercise and consistent with the improved neurological recovery, decreased infarct volumes and increased 5-bromo-2'-deoxyuridine (BrdU) in the ipsilateral Subventricular zone (SVZ), as well as increased numbers of BrdU/DCX and BrdU/Neun-positive cells in the peri-infarct region. Furthermore, we observed that the treadmill exercise-induced increased VEGF expression, improved neurological recovery, decreased infarct volumes, increased BrdU/DCX and BrdU/Neun-positive cells were significantly inhibited by the caveolin-1 inhibitor. Our results indicate that treadmill exercise improves neurological recovery in ischemic rats, possibly by enhancement of SVZ-derived neural stem cell (NSC) proliferation, migration and differentiation in the penumbra. Moreover, caveolin-1/VEGF signaling is involved in exercise-mediated NSC migration and neuronal differentiation.

  1. Ischemic strokes and migraine

    Energy Technology Data Exchange (ETDEWEB)

    Bousser, M.G.; Baron, J.C.; Chiras, J.

    1985-11-01

    Lasting neurological deficits, though most infrequent, do occur in migrainous subjects and are well documented by clinical angiographic computed tomographic (CT scan) and even pathological studies. However the mechanism of cerebral ischemia in migraine remains widely unknown and the precise role of migraine in the pathogenesis of ischemic strokes is still debated. (orig./MG).

  2. Current trends in the management of acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Srinivasan Paramasivam

    2015-01-01

    Full Text Available Stroke is the leading cause of disability and most of the cases are those of ischemic stroke. Management strategies especially for large vessel occlusive stroke have undergone a significant change in the recent years that include widespread use of thrombolytic medications followed by endovascular clot removal. For successful treatment by endovascular thrombectomy, the important factors are patient selection based on clinical criterion including age, time of onset, premorbid clinical condition, co-morbidities, National Institute of Health Stroke Scale, and imaging criterion including computed tomography (CT head, CT angiogram and CT perfusion. Patients presenting within 4.5 hours of onset are considered for intravenous (IV recombinant tissue plasminogen activator treatment. Mechanical clot retrieval devices have evolved over the past decade. The Mechanical Embolus Removal in Cerebral Ischemia device was approved first followed by the penumbra revascularization system. They have proven in various studies to improve recanalization with acceptable rates of symptomatic intra-cerebral hemorrhage. Introduction of stent retrievers has led to a new era in the interventional management of acute ischemic stroke (AIS. Recent trials namely MRCLEAN, ESCAPE, SWIFT PRIMEs, and EXTEND-IA have used the stent retriever predominantly and have shown unequivocal benefit in the outcome at 90 days for AIS patients with large vessel occlusion. More recently, a new catheter namely 5 MAX ACE was introduced along with improvement in the suction device. This has led to a direct aspiration first pass technique resulting in faster recanalization. Advancements in the endovascular management of AIS with large vessel occlusion have resulted in a paradigm shift in the way this disease is managed. Improvements in patient selection using clinical and imaging criterion along with technical and technological advancements in mechanical thrombectomy have made possible a significantly

  3. Current trends in the management of acute ischemic stroke.

    Science.gov (United States)

    Paramasivam, Srinivasan

    2015-01-01

    Stroke is the leading cause of disability and most of the cases are those of ischemic stroke. Management strategies especially for large vessel occlusive stroke have undergone a significant change in the recent years that include widespread use of thrombolytic medications followed by endovascular clot removal. For successful treatment by endovascular thrombectomy, the important factors are patient selection based on clinical criterion including age, time of onset, premorbid clinical condition, co-morbidities, National Institute of Health Stroke Scale, and imaging criterion including computed tomography (CT) head, CT angiogram and CT perfusion. Patients presenting within 4.5 hours of onset are considered for intravenous (IV) recombinant tissue plasminogen activator treatment. Mechanical clot retrieval devices have evolved over the past decade. The Mechanical Embolus Removal in Cerebral Ischemia device was approved first followed by the penumbra revascularization system. They have proven in various studies to improve recanalization with acceptable rates of symptomatic intra-cerebral hemorrhage. Introduction of stent retrievers has led to a new era in the interventional management of acute ischemic stroke (AIS). Recent trials namely MRCLEAN, ESCAPE, SWIFT PRIMEs, and EXTEND-IA have used the stent retriever predominantly and have shown unequivocal benefit in the outcome at 90 days for AIS patients with large vessel occlusion. More recently, a new catheter namely 5 MAX ACE was introduced along with improvement in the suction device. This has led to a direct aspiration first pass technique resulting in faster recanalization. Advancements in the endovascular management of AIS with large vessel occlusion have resulted in a paradigm shift in the way this disease is managed. Improvements in patient selection using clinical and imaging criterion along with technical and technological advancements in mechanical thrombectomy have made possible a significantly improved outcome

  4. Dyslipidemia and Outcome in Patients with Acute Ischemic Stroke

    Institute of Scientific and Technical Information of China (English)

    XU Tian; ZHANG Jin Tao; YANG Mei; ZHANG Huan; LIU Wen Qing; KONG Yan; XU Tan; ZHANG Yong Hong

    2014-01-01

    ObjectiveTo study the relationship between dyslipidemia and outcome in patients with acute ischemic stroke. MethodsData about 1 568 patients with acute ischemic stroke werecollected from 4 hospitals in Shandong Province from January 2006 to December 2008. National Institute of Health Stroke Scale (NIHSS) >10 at discharge or death was defined as the outcome. Effect of dyslipidemia on outcome in patients with acute ischemic stroke was analyzed by multivariate logistic regression analysis and propensity score-adjusted analysis, respectively. ResultsThe serum levels of TC, LDL-C, and HDL-C were significantly associated with the outcome in patients with acute ischemic stroke. Multivariate logistic regression analysis and propensity score-adjusted analysis showed that the ORs and 95% CIs were 3.013 (1.259, 7.214)/2.655 (1.298, 5.43), 3.157(1.306, 7.631)/3.405(1.621, 7.154), and 0.482 (0.245, 0.946)/0.51 (0.282, 0.921), respectively, for patients with acute ischemic stroke. Hosmer-Lemeshow goodness-of-fit test showed no significant difference in observed and predicted risk in patients with acute ischemic stroke (chi-square=8.235, P=0.411). ConclusionSerum levels of TC, LDL-C, and HDL-C are positively related with the outcome in patients with acute ischemic stroke.

  5. Detección de Zonas de Penumbra y Visibilidad a los Flujos Electromagnéticos en Campos Abiertos

    Directory of Open Access Journals (Sweden)

    Jairo Madrigal-Argáez

    2007-12-01

    Full Text Available This article exhibits a computational procedure that allows, on a Terrain Elevation Map (TEM of a geographic region of interest, are as that are in line with direct impact of energy flows generated from point sources located. This presents visually, the geographical are as of visibility and penumbras of electromagnetic radiation of punctual sources. In developing of the exercise ha ve be en covered two aspects: the first produces a 3D geometric model that represents the topographic profile of geographical regions, based on the available databases as a result ofthe project SRTM (NGA and NASA[8]. The second, proposed a model of propagation for a radiation so urce wave in the space free of charge and sources in homogeneous and isotropic regions, according to the solution of Maxwell to the propagation of electromagnetic waves and in accordance with the law and Snell and techniques of Ray-Tracing (RT.

  6. Temporal profile of experimental ischemic edema after threshold amount of insult to induce infarction--ultrastructure, gravimetry and Evans' blue extravasation.

    Science.gov (United States)

    Ito, U; Kuroiwa, T; Hanyu, S; Hakamata, Y; Kawakami, E; Nakano, I; Oyanagi, K

    2003-01-01

    When a threshold amount of temporary ischemic insult to induce focal infarction was given to the unilateral cerebral hemisphere of gerbils, a small focal infarct surrounded by a wide penumbra developed in the rostral portion of the cerebral cortex. During the first 5 hours following recirculation, whole astrocytic cell bodies and processes in the ischemic hemisphere were swollen, with an increase in the number of glycogen granules and in number and size of mitochondria. This swelling was an active reaction of astrocytes for neuronal protection, scavenging potassium, glutamate, and other neuronal metabolic products, and for generating fuels for neurons (cyto-reactive edema). This reactive astrocytic swelling continued in the penumbra, but some dead neurons were found disseminated among the surviving neurons. Whereas, at 12 approximately 48 hours, focal infarction developed in which all cell membranes lost their Gibbs-Donnan's equilibrium due to energetic failure of their membranous Na+/K+ ATPase. This is the cytotoxic edema (cyto-necrotic edema). In the infarct focus, when pericapillary astrocytic end-feet were damaged, the capillary BBB was broken; and thus vasogenic edema was superimposed on the cytotoxic edema.

  7. Arterial Spin Labeling Perfusion Magnetic Resonance Imaging Performed in Acute Perinatal Stroke Reveals Hyperperfusion Associated With Ischemic Injury.

    Science.gov (United States)

    Watson, Christopher G; Dehaes, Mathieu; Gagoski, Borjan A; Grant, P Ellen; Rivkin, Michael J

    2016-06-01

    Perfusion-weighted imaging in adults with acute stroke often reveals hypoperfusion in the ischemic core and in a surrounding area of nondiffusion-restricted penumbral tissue. Perinatal stroke is common, but the perfusion pattern is rarely documented. We aimed to describe the perfusion pattern in newborns with perinatal stroke. Neonates with clinical features of acute stroke underwent magnetic resonance imaging. Perfusion data were obtained using pseudocontinuous arterial spin labeling. Strokes were classified as arterial, venous, or both. Core infarction was determined by the presence of restricted diffusion on diffusion-weighted imaging. Perfusion-weighted imaging and susceptibility-weighted imaging signal in the ischemic area were visually compared with the homologous region in the contralesional hemisphere. Electroencephalogram data were evaluated for seizure activity. In 25 neonates with acute stroke, 8 of 11 (73%) with arterial ischemic stroke demonstrated hyperperfusion, 1 of 9 (11%) with venous stroke, and 4 of 5 (80%) with both. Hypoperfusion was observed in 3 of 9 (33%) with venous and none with arterial ischemic stroke. Perfusion was normal in 4 of 9 (45%) with venous and 1 of 5 (20%) with both. Twenty-one of 24 patients (88%) with electroencephalogram data had either electrographic seizures or focal sharp waves in the ipsilesional hemisphere (11/11 arterial ischemic stroke, 6/9 venous, and 4/5 both). Perfusion-weighted imaging can be obtained in neonates with acute stroke and often reveals hyperperfusion in the infarct core. Penumbra in arterial ischemic stroke is seldom found. Hyperperfusion may be caused by poststroke reperfusion or to neuronal hyperexcitability of stroke-associated seizure. Its identification may be useful for consideration of therapy for acute neonatal stroke. © 2016 American Heart Association, Inc.

  8. Inhibition of autophagy contributes to ischemic postconditioning-induced neuroprotection against focal cerebral ischemia in rats.

    Directory of Open Access Journals (Sweden)

    Li Gao

    Full Text Available BACKGROUND: Ischemic postconditioning (IPOC, or relief of ischemia in a stuttered manner, has emerged as an innovative treatment strategy to reduce programmed cell death, attenuate ischemic injuries, and improve neurological outcomes. However, the mechanisms involved have not been completely elucidated. Recent studies indicate that autophagy is a type of programmed cell death that plays elusive roles in controlling neuronal damage and metabolic homeostasis. This study aims to determine the role of autophagy in IPOC-induced neuroprotection against focal cerebral ischemia in rats. METHODOLOGY/PRINCIPAL FINDINGS: A focal cerebral ischemic model with permanent middle cerebral artery (MCA occlusion plus transient common carotid artery (CCA occlusion was established. The autophagosomes and the expressions of LC3/Beclin 1/p62 were evaluated for their contribution to the activation of autophagy. We found that autophagy was markedly induced with the upregulation of LC3/Beclin 1 and downregulation of p62 in the penumbra at various time intervals following ischemia. IPOC, performed at the onset of reperfusion, reduced infarct size, mitigated brain edema, inhibited the induction of LC3/Beclin 1 and reversed the reduction of p62 simultaneously. Rapamycin, an inducer of autophagy, partially reversed all the aforementioned effects induced by IPOC. Conversely, autophagy inhibitor 3-methyladenine (3-MA attenuated the ischemic insults, inhibited the activation of autophagy, and elevated the expression of anti-apoptotic protein Bcl-2, to an extent comparable to IPOC. CONCLUSIONS/SIGNIFICANCE: The present study suggests that inhibition of the autophagic pathway plays a key role in IPOC-induced neuroprotection against focal cerebral ischemia. Thus, pharmacological inhibition of autophagy may provide a novel therapeutic strategy for the treatment of stroke.

  9. Efficacy of a coaxial system with a compliant balloon catheter for navigation of the Penumbra reperfusion catheter in tortuous arteries: technique and case experience.

    Science.gov (United States)

    Takahira, Kazuki; Kataoka, Taketo; Ogino, Tatsuya; Endo, Hideki; Nakamura, Hirohiko

    2017-04-01

    OBJECTIVE The authors describe a method by which they easily and atraumatically navigate a large-bore reperfusion catheter of the Penumbra system to an embolus by using a coaxial system with a compliant balloon catheter in patients with tortuous arteries. METHODS A retrospective review of the prospective endovascular database was performed to identify cases in which a coaxial system with a compliant balloon catheter (Scepter C, MicroVention/Terumo; or TransForm C, Stryker Neurovascular) and a large-bore reperfusion catheter of the Penumbra system (Penumbra, Inc.) was used. The authors achieved a stable guiding sheath position and delivered the coaxial system with a compliant balloon catheter and a large-bore reperfusion catheter. Then, the balloon was inflated somewhat when the distal tip of the balloon was slightly advanced from the tip of the reperfusion catheter, and together the coaxial system was advanced to an embolus over a 0.014-in guidewire, even around the corner. When the distal tip of the balloon catheter reached the embolus, the authors deflated the balloon and navigated the large-bore reperfusion catheter to the embolus. Finally, the aspiration of the embolus with the Penumbra MAX pump was begun. RESULTS Between May 2014 and September 2015, the authors used this technique in 17 cases: 16 cases of middle cerebral artery occlusion (including 5 cases of internal carotid artery occlusion) and 1 case of basilar artery occlusion (age range 36-88 years, mean age 74.7 years, 13 men). For the reperfusion catheter of the Penumbra system, the 5MAX ACE was used in 15 cases, and the 5MAX was used in 2 cases. As a compliant balloon catheter, the Scepter C was used in 16 cases, and the TransForm C was used in 1 case. The technique was successful in 16 cases (94.1%). No parent artery dissections were noted in any cases. Catheter-induced vasospasm was noted in 1 case, but the vasospasm was transient. CONCLUSIONS A coaxial system with a compliant balloon catheter can

  10. Perfusion CT in acute ischemic stroke: a qualitative and quantitative comparison of deconvolution and maximum slope approach.

    Science.gov (United States)

    Abels, B; Klotz, E; Tomandl, B F; Kloska, S P; Lell, M M

    2010-10-01

    PCT postprocessing commonly uses either the MS or a variant of the DC approach for modeling of voxel-based time-attenuation curves. There is an ongoing discussion about the respective merits and limitations of both methods, frequently on the basis of theoretic reasoning or simulated data. We performed a qualitative and quantitative comparison of DC and MS by using identical source datasets and preprocessing parameters. From the PCT data of 50 patients with acute ischemic stroke, color maps of CBF, CBV, and various temporal parameters were calculated with software implementing both DC and MS algorithms. Color maps were qualitatively categorized. Quantitative region-of-interest-based measurements were made in nonischemic GM and WM, suspected penumbra, and suspected infarction core. Qualitative results, quantitative results, and PCT lesion sizes from DC and MS were statistically compared. CBF and CBV color maps based on DC and MS were of comparably high quality. Quantitative CBF and CBV values calculated by DC and MS were within the same range in nonischemic regions. In suspected penumbra regions, average CBF(DC) was lower than CBF(MS). In suspected infarction core regions, average CBV(DC) was similar to CBV(MS). Using adapted tissue-at-risk/nonviable-tissue thresholds, we found excellent correlation of DC and MS lesion sizes. DC and MS yielded comparable qualitative and quantitative results. Lesion sizes indicated by DC and MS showed excellent agreement when using adapted thresholds. In all cases, the same therapy decision would have been made.

  11. Blood Biomarkers of Ischemic Stroke

    National Research Council Canada - National Science Library

    Jickling, Glen C; Sharp, Frank R

    2011-01-01

    .... Though many candidate blood based biomarkers for ischemic stroke have been identified, none are currently used in clinical practice. With further well designed study and careful validation, the development of blood biomarkers to improve the care of patients with ischemic stroke may be achieved.

  12. In vivo characterization of ischemic small intestine using bioimpedance measurements.

    Science.gov (United States)

    Strand-Amundsen, R J; Tronstad, C; Kalvøy, H; Gundersen, Y; Krohn, C D; Aasen, A O; Holhjem, L; Reims, H M; Martinsen, Ø G; Høgetveit, J O; Ruud, T E; Tønnessen, T I

    2016-02-01

    The standard clinical method for the assessment of viability in ischemic small intestine is still visual inspection and palpation. This method is non-specific and unreliable, and requires a high level of clinical experience. Consequently, viable tissue might be removed, or irreversibly damaged tissue might be left in the body, which may both slow down patient recovery. Impedance spectroscopy has been used to measure changes in electrical parameters during ischemia in various tissues. The physical changes in the tissue at the cellular and structural levels after the onset of ischemia lead to time-variant changes in the electrical properties. We aimed to investigate the use of bioimpedance measurement to assess if the tissue is ischemic, and to assess the ischemic time duration. Measurements were performed on pigs (n = 7) using a novel two-electrode setup, with a Solartron 1260/1294 impedance gain-phase analyser. After induction of anaesthesia, an ischemic model with warm, full mesenteric arterial and venous occlusion on 30 cm of the jejunum was implemented. Electrodes were placed on the serosal surface of the ischemic jejunum, applying a constant voltage, and measuring the resulting electrical admittance. As a control, measurements were done on a fully perfused part of the jejunum in the same porcine model. The changes in tan δ (dielectric parameter), measured within a 6 h period of warm, full mesenteric occlusion ischemia in seven pigs, correlates with the onset and duration of ischemia. Tan δ measured in the ischemic part of the jejunum differed significantly from the control tissue, allowing us to determine if the tissue was ischemic or not (P < 0.0001, F = (1,75.13) 188.19). We also found that we could use tan δ to predict ischemic duration. This opens up the possibility of real-time monitoring and assessment of the presence and duration of small intestinal ischemia.

  13. [Ischemic hepatitis. Case report].

    Science.gov (United States)

    Squella, Freddy; Zapata, Rodrigo

    2003-06-01

    Ischemic hepatitis or shock liver is defined as an extensive hepatocellular necrosis associated with a decrease in hepatic perfusion due to systemic hypotension. Serum aminotransferase levels (ALAT and ASAT) increase rapidly after the ischemic episode and peak within 1 to 3 days to at least 20 times the upper normal limit. After recovery, aminotransferases return to near normal levels in 7-10 days of the initial insult. Histological it is characterized by centrolobular necrosis without inflammation. We report a 47 years old woman with a rheumatic mitral valve disease, atrial fibrillation on anticoagulation and congestive heart failure. She was admitted due to a rapid auricular arrhythmia and secondary severe hypotension. She developed rapidly progressive jaundice (bilirubin up to 8.9 mg/dl) and her aminotransferases (ALAT and ASAT) increased rapidly to levels near 100 times the upper normal limit. Other causes of liver disease were excluded. With hemodynamic support and after heart rate control she improved rapidly within the following 10 days with normalization of liver function tests and complete clinical recovery.

  14. Mixing intensity modulated electron and photon beams: combining a steep dose fall-off at depth with sharp and depth-independent penumbras and flat beam profiles.

    Science.gov (United States)

    Korevaar, E W; Heijmen, B J; Woudstra, E; Huizenga, H; Brahme, A

    1999-09-01

    For application in radiotherapy, intensity modulated high-energy electron and photon beams were mixed to create dose distributions that feature: (a) a steep dose fall-off at larger depths, similar to pure electron beams, (b) flat beam profiles and sharp and depth-independent beam penumbras, as in photon beams, and (c) a selectable skin dose that is lower than for pure electron beams. To determine the required electron and photon beam fluence profiles, an inverse treatment planning algorithm was used. Mixed beams were realized at a MM50 racetrack microtron (Scanditronix Medical AB, Sweden), and evaluated by the dose distributions measured in a water phantom. The multileaf collimator of the MM50 was used in a static mode to shape overlapping electron beam segments, and the dynamic multileaf collimation mode was used to realize the intensity modulated photon beam profiles. Examples of mixed beams were generated at electron energies of up to 40 MeV. The intensity modulated electron beam component consists of two overlapping concentric fields with optimized field sizes, yielding broad, fairly depth-independent overall beam penumbras. The matched intensity modulated photon beam component has high fluence peaks at the field edges to sharpen this penumbra. The combination of the electron and the photon beams yields dose distributions with the characteristics (a)-(c) mentioned above.

  15. False ischaemic penumbras in CT perfusion in patients with carotid artery stenosis and changes following angioplasty and stenting.

    Science.gov (United States)

    Mosqueira, A J; Pumar, J M; Arias, S; Rodríguez-Yáñez, M; Blanco Ulla, M; Vázquez Herrero, F; Castillo, J

    2017-08-30

    Carotid artery stenosis influences CT perfusion (CTP) studies, sometimes manifesting as a false ischaemic penumbra (FIP). This study aims to estimate the incidence of FIP in patients with carotid artery stenosis, establish their relationship with the degree of stenosis, and measure quantitative and qualitative changes in CTP after carotid angioplasty and stenting (CAS). Between October 2013 and June 2015, we prospectively selected 26 patients with carotid stenosis who underwent CAS, with CTP being performed 2-10 days before and after CAS. Sixteen patients had unilateral stenosis (11 in the subgroup displaying < 90% stenosis and 5 in the subgroup with ≥ 90% stenosis) and 10 patients had bilateral stenosis. The incidence of FIP in patients with carotid artery stenosis was 38.5%. Risk of FIP increased in direct relation to degree of stenosis, with a relative risk of 11 in the subgroup with ≥ 90% stenosis with respect to the subgroup displaying < 90% stenosis (95% CI, 1.7-71.3; P=.0005). There were statistically significant changes in the parameters CBF, TTP, MTT, and Tmax CTP, which reverted after angioplasty. No significant changes were found in CBV. Carotid artery stenosis involves changes in CTP parameters. Patients with ≥ 90% stenosis carry a high risk of FIP; CTP studies may therefore be misinterpreted in these cases. Changes in CTP parameters are reverted after CAS. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Clinical Significance of T-wave Alternans Predicting Sudden Cardiac Death in Patients with Ischemic Heart Disease%T波电交替预测缺血性心脏病心脏性猝死的临床意义

    Institute of Scientific and Technical Information of China (English)

    孙溢晗(综述); 张月兰(审校)

    2015-01-01

    中国每年心脏性猝死人数约54.4万人,主要病因为缺血性心脏病所致恶性心律失常,所以及时有效检测减少心脏性猝死发生对降低心血管病病死率有重要意义。2008年AHA/ACC/HRS联合发表了“无创技术对心脏性猝死危险分层的专家共识”,指出用于识别心脏性猝死高危患者的无创检测指标,包括常规心电图、平均信号心电图、动态心电图、心电图运动试验(T波电交替)及压力感受器敏感性等。其中T波电交替为心电图上ST段或T波形态及振幅变化现象,是一种心电活动不稳定现象,具有在临床应用、随访复查方面更为方便灵活,操作简单及较高阳性识别率等特点,成为预测缺血性心脏病致恶性心律失常及心脏性猝死的主要无创性检测指标之一。%The number of sudden cardiac death in China is about 54.4 million people each year, and the main reason is malignant ar-rhythmias caused by ischemic heart disease, so it does significantly to reduce the incidence of sudden cardiac death and cardiovascular mor-tality by predicting timely and effectively.In 2008, AHA/ACC/HRS published ‘Expert consensus on risk stratification of sudden cardiac death through non-invasive techniques’ , which pointed out non-invasive methods were ECG, ventricular late potential, Holter, T-wave alter-nans, and baroneflex sensitivity.T-wave alternans is instability of electrical activity ECG phenomenon, on which ST segment or T wave mor-phology and amplitude changes, which is more convenient and flexible used in clinical or follow-up, and becomes one of major non-invasive detections of indicators of malignant arrhythmias and sudden cardiac death.

  17. Analysis for Risk Factors and Predictive Value of LDL/HDL Ratio in Acute Ischemic Stroke Recurrence%急性缺血性脑卒中复发危险因素分析及低密度脂蛋白与高密度脂蛋白比值对脑卒中复发的预测价值

    Institute of Scientific and Technical Information of China (English)

    李琦; 钟纯正

    2014-01-01

    目的:探讨急性缺血性脑卒中复发危险因素,并分析低密度脂蛋白(LDL)/高密度脂蛋白(HDL)的预测价值。  方法:对我院收治的143例急性缺血性脑卒中患者进行为期2年的随访,探讨患者复发的危险因素以及LDL/HDL与脑卒中复发的相关性,分析LDL/HDL在脑卒中复发中的预测价值。  结果:单因素分析显示,腔隙性脑梗死、有无合并高血压、血压、LDL、HDL、LDL/HDL、甘油三酯(TG)水平,以及脑卒中量表评分和生活能力评分是导致缺血性脑卒中复发的危险因素;多因素分析显示合并高血压、LDL/HDL、TG水平是导致缺血性脑卒中复发的独立危险因素。LDL、LDL/HDL与脑卒中复发呈明显正相关关系,HDL水平与脑卒中复发呈负相关(P  结论:LDL/HDL预测缺血性脑卒中复发的作用有利于我们识别缺血性脑卒中复发的高危患者,有利于临床进行早期的干预和预防。%Objective: To analyze the risk factors and the predictive value of LDL/HDL ratio in acute ischemic stroke recurrence. Methods: A total of 143 patients with acute ischemic stroke treated in our hospital were studied. The patients were followed-up for 2 years, the risk factors and the predictive value of LDL/HDL ratio for stroke recurrence were analyzed. Results: Single factor analysis indicated that lacunar infarction, hypertension, blood pressure, the levels of LDL, HDL, ratio of LDL/HDL, stroke scale score, life ability score were the risk factors of ischemic stroke recurrence. Multivariate analysis presented that hypertension, ratio of LDL/HDL, TG level were the independent risk factors for ischemic stroke recurrence. LDL and ratio of LDL/HDL were positively related to ischemic stroke recurrence, HDL was negatively related to ischemic stroke recurrence, P Conclusion: The predictive value of LDL/HDL ratio could help us to identify the patients with high risk of ischemic stroke

  18. [Cerebrolysin for acute ischemic stroke].

    Science.gov (United States)

    iganshina, L E; Abakumova, T R

    2013-01-01

    The review discusses existing evidence of benefits and risks of cerebrolysin--a mixture of low-molecular-weight peptides and amino acids derived from pigs' brain tissue with proposed neuroprotective and neurotrophic properties, for acute ischemic stroke. The review presents results of systematic search and analysis of randomised clinical trials comparing cerebrolysin with placebo in patients with acute ischemic stroke. Only one trial was selected as meeting quality criteria. No difference in death and adverse events between cerebrolysin and placebo was established. The authors conclude about insufficiency of evidence to evaluate the effect of cerebrolysin on survival and dependency in people with acute ischemic stroke.

  19. Hemichorea after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Sadullah Saglam

    2016-03-01

    Full Text Available The deterioration of the balance between direct and indirect ways in the basal ganglia causes chorea. The lesions of contralateral basal ganglia, thalamus or the connection of them all together are responsible for this. Chorea can be observed during the course of metabolic and vascular diseases, neurodegenerative or hereditary diseases. Hyperkinetic movement disorders after acute ischemic stroke are reported as rare; however, hemichorea is the most frequent developing disorder of hyperkinetic movement as a result of cerebrovascular disease. In this case report, we presented two case who applied us with choreiform movements in his left half of the body after acute thalamic stroke. [Cukurova Med J 2016; 41(0.100: 29-32

  20. Preserved Collateral Blood Flow in the Endovascular M2CAO Model Allows for Clinically Relevant Profiling of Injury Progression in Acute Ischemic Stroke

    Science.gov (United States)

    Little, Philip; Kvist, Ola; Grankvist, Rikard; Jonsson, Stefan; Damberg, Peter; Söderman, Michael; Arnberg, Fabian; Holmin, Staffan

    2017-01-01

    Interventional treatment regimens have increased the demand for accurate understanding of the progression of injury in acute ischemic stroke. However, conventional animal models severely inhibit collateral blood flow and mimic the malignant infarction profile not suitable for treatment. The aim of this study was to provide a clinically relevant profile of the emergence and course of ischemic injury in cases suitable for acute intervention, and was achieved by employing a M2 occlusion model (M2CAO) that more accurately simulates middle cerebral artery (MCA) occlusion in humans. Twenty-five Sprague-Dawley rats were subjected to Short (90 min), Intermediate (180 min) or Extended (600 min) transient M2CAO and examined longitudinally with interleaved diffusion-, T2- and arterial spin labeling perfusion-weighted magnetic resonance imaging before and after reperfusion. We identified a rapid emergence of cytotoxic edema within tissue regions undergoing infarction, progressing in several distinct phases in the form of subsequent moderation and then reversal at 230 min (p < 0.0001). We identified also the early emergence of vasogenic edema, which increased consistently before and after reperfusion (p < 0.0001). The perfusion of the penumbra correlated more strongly to the perfusion of adjacent tissue regions than did the perfusion of regions undergoing infarction (p = 0.0088). This was interpreted as an effect of preserved collateral blood flow during M2CAO. Accordingly, we observed only limited recruitment of penumbra regions to the infarction core. However, a gradual increase in infarction size was still occurring as late as 10 hours after M2CAO. Our results indicate that patients suffering MCA branch occlusion stand to benefit from interventional therapy for an extended time period after the emergence of ischemic injury. PMID:28068417

  1. Mechanical thrombectomy for acute ischemic stroke with cerebral microbleeds.

    Science.gov (United States)

    Shi, Zhong-Song; Duckwiler, Gary R; Jahan, Reza; Tateshima, Satoshi; Gonzalez, Nestor R; Szeder, Viktor; Saver, Jeffrey L; Kim, Doojin; Ali, Latisha K; Starkman, Sidney; Vespa, Paul M; Salamon, Noriko; Villablanca, J Pablo; Viñuela, Fernando; Feng, Lei; Loh, Yince; Liebeskind, David S

    2016-06-01

    The influence of cerebral microbleeds (CMBs) on post-thrombolytic hemorrhagic transformation (HT) in patients with acute ischemic stroke remains controversial. To investigate the association of CMBs with HT and clinical outcomes among patients with large-vessel occlusion strokes treated with mechanical thrombectomy. We analyzed patients with acute stroke treated with Merci Retriever, Penumbra system or stent-retriever devices. CMBs were identified on pretreatment T2-weighted, gradient-recall echo MRI. We analyzed the association of the presence, burden, and distribution of CMBs with HT, procedural complications, in-hospital mortality, and clinical outcome. CMBs were detected in 37 (18.0%) of 206 patients. Seventy-three foci of microbleeds were identified. Fourteen patients (6.8%) had ≥2 CMBs, only 1 patient had ≥5 CMBs. Strictly lobar CMBs were found in 12 patients, strictly deep CMBs in 12 patients, strictly infratentorial CMBs in 2 patients, and mixed CMBs in 11 patients. There were no significant differences between patients with CMBs and those without CMBs in the rates of overall HT (37.8% vs 45.6%), parenchymal hematoma (16.2% vs 19.5%), procedure-related vessel perforation (5.4% vs 7.1%), in-hospital mortality (16.2% vs 18.3%), and modified Rankin Scale score 0-3 at discharge. CMBs were not independently associated with HT or in-hospital mortality in patients treated with either thrombectomy or intravenous thrombolysis followed by thrombectomy. Patients with CMBs are not at increased risk for HT and mortality following mechanical thrombectomy for acute stroke. Excluding such patients from mechanical thrombectomy is unwarranted. The risk of HT in patients with ≥5 CMBs requires further study. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  2. Development and Validation of Intracranial Thrombus Segmentation on CT Angiography in Patients with Acute Ischemic Stroke

    NARCIS (Netherlands)

    Santos, E.M.M.; Marquering, H.A.; Berkhemer, O.A.; Van Zwam, W.H.; Van der Lugt, A.; Majoie, C.B.; Niessen, W.J.

    2014-01-01

    Background and Purpose: Thrombus characterization is increasingly considered important in predicting treatment success for patients with acute ischemic stroke. The lack of intensity contrast between thrombus and surrounding tissue in CT images makes manual delineation a difficult and time consuming

  3. Development and validation of intracranial thrombus segmentation on CT angiography in patients with acute ischemic stroke

    NARCIS (Netherlands)

    Santos, E.M.; Marquering, H.A.; Berkhemer, O.A.; Zwam, W.H. van; Lugt, A. van der; Majoie, C.B.; Niessen, W.J.; Dijk, E.J. van

    2014-01-01

    BACKGROUND AND PURPOSE: Thrombus characterization is increasingly considered important in predicting treatment success for patients with acute ischemic stroke. The lack of intensity contrast between thrombus and surrounding tissue in CT images makes manual delineation a difficult and time consuming

  4. CT perfusion imaging and CT subtraction angiography in the diagnosis of ischemic cerebrovascular disease within 24 hours

    Institute of Scientific and Technical Information of China (English)

    管小亭; 于学英; 刘翔; 龙洁; 戴建平

    2003-01-01

    Objective To evaluate the value of the clinical use of CT perfusion imaging (CTPI) and CT subtraction angiography (CTSA) for diagnosing acute ischemic cerebrovascular disease (AICVD). Methods Twenty-four patients with AICVD onset within 24 hours were examined with regular CT, CTPI, and CTSA. Some cases received CTPI, magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), digital subtraction angiography (DSA) or single photon emission computer tomography (SPECT) during follow-up examinations.Results Of the 24 cases, 11 had negative results from regular CT scans 3-6 hours after onset of stroke in 6 cases, 6-12 hours in 3 cases, and 12-24 hours in 2 cases. Ten of these cases were then confirmed by CTPI as having ischemic lesions, 2 with middle cerebral artery occlusion (MCAO), and 1 case with transient ischemic attack (TIA) with CTPI negative. Of the 24 cases, 13 had positive results from regular CT, 9 were diagnosed with ischemic lesions larger by using CTPI than regular CT, 1 case had MCAO and 1 had internal carotid artery occlusion (ICAO). There were 4 cases with ischemic lesions observed with regular CT having nearly the same range as that of lacunar infarctions using CTPI. Another 4 cases had more than 2 lesion areas. The peak time (PT), mean transit time (MTT) and relative flow (RF) of 24 cases were markedly different. The sides of ischemic lesions compared to each other and the core of the lesion compared to peripheral zones were also altered significantly (P<0.01).Conclusions Combined CTPI with CTSA can detect acute ischemic lesions at early and hyper-early stages and could distinguish between TIA, lacunar infarction and a larger area of infarction. Using semiquantitative blood perfusion analysis status, CTPI with CTSA could define position, area and range of the ischemic lesion and penumbra. These scans can also analyze the brain blood perfusion status. It is important to early diagnose the occlusion of the entire division of the internal

  5. Let's Talk about Ischemic Stroke

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Let's Talk About Ischemic Stroke Updated:Dec 9,2015 The majority of strokes ... Should I Limit Sodium? How Do I Understand "Nutrition Facts" Labels? How Can I Quit Smoking? How ...

  6. Thrombolysis for Acute Ischemic Stroke

    NARCIS (Netherlands)

    Uyttenboogaart, Maarten; De Keyser, J.; Luijckx, G. J.

    2009-01-01

    In the last decennium, thrombolytic therapy has changed the management of acute ischemic stroke. Randomized clinical studies have demonstrated that intravenous thrombolysis with tissue plasminogen activator improves functional outcomes. Recently the time window for intravenous thrombolysis has been

  7. Cryoglobulins in Acute Ischemic Stroke

    Science.gov (United States)

    Manukyan, L. A.; Ayvazyan, V. A.; Boyajyan, A. S.

    Cryoglobulins (Cgs) are pathogenic immune complexes, non specific markers of the inflammatory and autoimmune responses. In this study we for the first time, revealed Cgs in the blood of ischemic stroke patients and analyze their composition.

  8. Can Doppler flow parameters of carotid stenosis predict the occurrence of new ischemic brain lesions detected by diffusion-weighted MR imaging after filter-protected internal carotid artery stenting?

    Science.gov (United States)

    Gunduz, Y; Akdemir, R; Ayhan, L T; Keser, N

    2014-04-01

    Carotid angioplasty and stent placement are increasingly being used for the treatment of symptomatic and asymptomatic carotid artery disease. Carotid angioplasty and stent placement carry an inherent risk of distal cerebral embolization, precipitating new brain ischemic lesions and neurologic symptoms. Our purpose was to evaluate the frequency of new ischemic lesions found on diffusion-weighted imaging after protected carotid angioplasty and stent placement and to determine the association of new lesions with ICA Doppler flow parameters. Fifty-two patients (mean age, 68 ± 11 years) with 50%-69% (n = 20, group 1) and ≥70% (n = 32, group 2) internal carotid artery stenosis underwent carotid angioplasty and stent placement with distal filter protection. DWI was performed before and 48 hours after carotid angioplasty and stent placement. Thirty-three (63.4%) patients showed new lesions. The average number of new postprocedural lesions was 3.4 per patient. Most of the postprocedural lesions were <5 mm (range, 3-23 mm), cortical and corticosubcortical, and clinically silent. Group 2 had a significantly higher number of new lesions compared with group 1 (P < .001). A significant relationship was found between ICA Doppler flow parameters and the appearance of new lesions. The appearance of new ischemic lesions was significantly related to the Doppler flow parameters, particularly peak systolic velocity.

  9. Predictive Value of ECG and Echocardiography in Predicting the Responsible Blood Vessels of Ischemic Heart Disease%心电图及超声心动图对缺血性心脏病责任血管的预测价值#

    Institute of Scientific and Technical Information of China (English)

    于倩; 袁琛; 张坤; 石伟; 张军

    2016-01-01

    目的:探讨心电图(ECG)及超声心动图与缺血性心脏病责任血管的相关性。方法:缺血性心脏病患者2568例行冠状动脉造影术,以造影检查结果作为评价标准,将ECG及超声心动图的诊断结果与缺血性心脏病责任血管的关系进行分析。结果:冠状动脉单支病变组发病率高,占73.93%,单支病变组中以前降支发病率高,占63.59%;ECG及超声心动图阳性改变与冠状动脉单支病变组、双支病变组、三支病变组有预测预测价值(P=0.000);ECG阳性改变对预测前降支狭窄敏感性有高于回旋支、右冠状动脉的趋势,但无差异无统计学意义(P=0.539);超声心动图阳性改变对预测前降支、回旋支、右冠状动脉病变差异有统计学意义(P=0.023)。结论:ECG及超声心动图阳性结果与缺血相关责任血管具有一定预测价值,但阴性不能排除缺血性心脏病。%[ABSTRACT]Objective: To investigate the relationship between electrocardiogram (ECG) and echocardiography in patients with ischemic heart disease. Methods: 2 568 patients with ischemic heart disease underwent coronary angiography, and the results were evaluated by angiography. The relationship between ECG and echocardiography was analyzed. Results: The incidence of coronary artery disease was high, and the incidence rate was 73.93%. ECG and echocardiography were compared with that of single coronary artery disease group, double branch lesion group and three branch lesion group. The positive change of ECG was significantly higher than that of the right coronary artery(P=0.539), but no significant difference was statistically significant(P=0.023). Conclusions: The positive results of ECG and echocardiography have some predictive value, but it can not rule out the ischemic heart disease.

  10. Prothrombin and risk of venous thromboembolism, ischemic heart disease and ischemic cerebrovascular disease in the general population

    DEFF Research Database (Denmark)

    Weischer, Maren; Juul, Klaus; Zacho, Jeppe

    2010-01-01

    OBJECTIVE: We tested the hypotheses that Prothrombin G20210A heterozygosity associate with increased risk of venous thromboembolism (VTE), ischemic heart disease (IHD), and ischemic cerebrovascular disease (ICVD) in the general population and re-tested risk of IHD and ICVD in two case......-control studies. METHODS: 9231 individuals from the Danish general population were followed for VTE (VTE=DVT+PE), deep venous thrombosis (DVT), pulmonary embolism (PE), IHD, myocardial infarction (MI), ICVD, and ischemic stroke (IS) for a median of 24 years. Case-control studies included 2461 IHD cases and 867.......0(1.0-3.8) for MI, 1.4(0.7-3.1) for ICVD, and 2.1(0.8-5.4) for IS. CONCLUSION: Prothrombin G20210A heterozygosity alone and in combination with Factor V Leiden R506Q heterozygosity predicts 1.5 and 6.0 fold risk of IHD compared to non-carriers....

  11. Electroacupuncture pretreatment attenuates cerebral ischemic injury through α7 nicotinic acetylcholine receptor-mediated inhibition of high-mobility group box 1 release in rats

    Directory of Open Access Journals (Sweden)

    Wang Qiang

    2012-01-01

    Full Text Available Abstract Background We have previously reported that electroacupuncture (EA pretreatment induced tolerance against cerebral ischemic injury, but the mechanisms underlying this effect of EA are unknown. In this study, we assessed the effect of EA pretreatment on the expression of α7 nicotinic acetylcholine receptors (α7nAChR, using the ischemia-reperfusion model of focal cerebral ischemia in rats. Further, we investigated the role of high mobility group box 1 (HMGB1 in neuroprotection mediated by the α7nAChR and EA. Methods Rats were treated with EA at the acupoint "Baihui (GV 20" 24 h before focal cerebral ischemia which was induced for 120 min by middle cerebral artery occlusion. Neurobehavioral scores, infarction volumes, neuronal apoptosis, and HMGB1 levels were evaluated after reperfusion. The α7nAChR agonist PHA-543613 and the antagonist α-bungarotoxin (α-BGT were used to investigate the role of the α7nAChR in mediating neuroprotective effects. The roles of the α7nAChR and HMGB1 release in neuroprotection were further tested in neuronal cultures exposed to oxygen and glucose deprivation (OGD. Results Our results showed that the expression of α7nAChR was significantly decreased after reperfusion. EA pretreatment prevented the reduction in neuronal expression of α7nAChR after reperfusion in the ischemic penumbra. Pretreatment with PHA-543613 afforded neuroprotective effects against ischemic damage. Moreover, EA pretreatment reduced infarct volume, improved neurological outcome, inhibited neuronal apoptosis and HMGB1 release following reperfusion, and the beneficial effects were attenuated by α-BGT. The HMGB1 levels in plasma and the penumbral brain tissue were correlated with the number of apoptotic neurons in the ischemic penumbra. Furthermore, OGD in cultured neurons triggered HMGB1 release into the culture medium, and this effect was efficiently suppressed by PHA-543,613. Pretreatment with α-BGT reversed the inhibitory effect

  12. Pathogenic mechanisms following ischemic stroke.

    Science.gov (United States)

    Khoshnam, Seyed Esmaeil; Winlow, William; Farzaneh, Maryam; Farbood, Yaghoob; Moghaddam, Hadi Fathi

    2017-07-01

    Stroke is the second most common cause of death and the leading cause of disability worldwide. Brain injury following stroke results from a complex series of pathophysiological events including excitotoxicity, oxidative and nitrative stress, inflammation, and apoptosis. Moreover, there is a mechanistic link between brain ischemia, innate and adaptive immune cells, intracranial atherosclerosis, and also the gut microbiota in modifying the cerebral responses to ischemic insult. There are very few treatments for stroke injuries, partly owing to an incomplete understanding of the diverse cellular and molecular changes that occur following ischemic stroke and that are responsible for neuronal death. Experimental discoveries have begun to define the cellular and molecular mechanisms involved in stroke injury, leading to the development of numerous agents that target various injury pathways. In the present article, we review the underlying pathophysiology of ischemic stroke and reveal the intertwined pathways that are promising therapeutic targets.

  13. Salvia miltiorrhiza and ischemic diseases

    Institute of Scientific and Technical Information of China (English)

    Xin-Yan JI; Benny K-H TAN; Yi-Zhun ZHU

    2000-01-01

    The demonstration of beneficial effects of salvia miltiorrhiza (DanShen) on ischemic diseases has revolutionized the management of angina pectoris, myocardial infarction (MI) or stroke in Chinese society. Experimental studies have shown that DanShen dilated coronary arteries, increased coronary blood flow, and scavenged free radicals in ischemic diseases, so that it reduced the cellular damage from ischemia and improved heart functions. Clinical trials also indicated that DanShen was an effective medicine for angina pectoris, MI, and stroke. This review will focus on DanShen's effects in angina pectoris, MI and stroke.

  14. [Pregnancy and acute ischemic stroke].

    Science.gov (United States)

    Bereczki, Dániel

    2016-05-15

    Pregnancy-related ischemic strokes play an important role in both maternal and fetal morbidity and mortality. Changes in hemostaseology and hemodynamics as well as risk factors related to or independent from pregnancy contribute to the increased stroke-risk during gestation and the puerperium. Potential teratogenic effects make diagnostics, acute therapy and prevention challenging. Because randomized, controlled trials are not available, a multicenter registry of patients with gestational stroke would be desirable. Until definite guidelines emerge, management of acute ischemic stroke during pregnancy remains individual, involving experts and weighing the risks and benefits.

  15. Segmentation of infarct in acute ischemic stroke from MR apparent diffusion coefficient and trace-weighted images

    Science.gov (United States)

    Li, Meng; Ai, Lin; He, Huiguang; Zheng, Zuofeng; Lv, Bin; Li, Wenjing; Yi, Jianhua; Chen, Xuejiao

    2009-10-01

    Evidence from several previous studies indicated that apparent diffusion coefficient (ADC) map was likely to reveal brain regions belonging to the ischemic penumbra, that is, areas that may be at risk of infarction in a few hours following stroke onset. Trace map overcomes the anisotropic diffusions of ADC map, so it is superior for evaluation of an infarct involving white matter. Mean shift (MS) approach has been successfully used for image segmentation, particularly in brain MR images. The aim of the study was to develop a tool for rapid and reliable segmentation of infarct in human acute ischemic stroke based on the ADC and trace maps using the MS approach. In addition, a novel method of 3-dimensional visualization was presented to provide useful insights into volume datasets for clinical diagnosis. We applied the presented method to clinical data. The results showed that it was consistent, fast (about 8-10 minutes per subject) and indistinguishable from an expert using manual segmentation when used our tool.

  16. Relative trochanteric overgrowth after ischemic necrosis in congenital dislocation of the hip.

    Science.gov (United States)

    Iwersen, L J; Kalen, V; Eberle, C

    1989-01-01

    To determine the relative trochanteric overgrowth after ischemic necrosis of the femoral head during treatment of congenital dislocation of the hip (CDH), we reviewed radiographs of patients with ischemic necrosis and no femoral side surgery. The articulotrochanteric distance (ATD) was recorded after physeal closure. Ischemic necrosis was classified with the systems proposed by Salter et al. and Kalamchi and MacEwen. The resultant overgrowth was correlated with these systems. The articulotrochanteric distance in 29 patients with a Trendelenburg gait was also measured. The Kalamchi classification is more useful for predicting relative trochanteric overgrowth. Children with an ATD of less than or equal to 0 mm are likely to have a Trendelenburg gait.

  17. D-dimer levels and stroke progression in patients with acute ischemic stroke and atrial fibrillation

    DEFF Research Database (Denmark)

    Krarup, L-H; Sandset, E C; Sandset, P M

    2011-01-01

    Krarup L-H, Sandset EC, Sandset PM, Berge E. D-dimer levels and stroke progression in patients with acute ischemic stroke and atrial fibrillation. Acta Neurol Scand: 2011: 124: 40-44. © 2010 John Wiley & Sons A/S. Background -  Patients with acute ischemic stroke and atrial fibrillation...... in patients with acute ischemic stroke and atrial fibrillation....... are at increased risk of stroke progression and recurrence. We sought to assess whether D-dimer and other markers of hemostatic activation could predict these adverse events in such patients. Method -  Blood samples were obtained from patients included in the Heparin in Acute Embolic Stroke Trial. Stroke...

  18. Advances in understanding ischemic acute kidney injury

    Directory of Open Access Journals (Sweden)

    Himmelfarb Jonathan

    2011-02-01

    Full Text Available Abstract Acute kidney injury (AKI is independently associated with increased morbidity and mortality. Ischemia is the leading cause of AKI, and short of supportive measures, no currently available therapy can effectively treat or prevent ischemic AKI. This paper discusses recent developments in the understanding of ischemic AKI pathophysiology, the emerging relationship between ischemic AKI and development of progressive chronic kidney disease, and promising novel therapies currently under investigation. On the basis of recent breakthroughs in understanding the pathophysiology of ischemic AKI, therapies that can treat or even prevent ischemic AKI may become a reality in the near future.

  19. Sex Hormones and Ischemic Stroke

    DEFF Research Database (Denmark)

    Holmegard, Haya N; Nordestgaard, Børge G; Jensen, Gorm B

    2016-01-01

    CONTEXT AND OBJECTIVE: Whether endogenous sex hormones are associated with ischemic stroke (IS) is unclear. We tested the hypothesis that extreme concentrations of endogenous sex hormones are associated with risk of IS in the general population. DESIGN, SETTING, AND PARTICIPANTS: Adult men (n...

  20. Olanzapine-induced ischemic colitis

    Directory of Open Access Journals (Sweden)

    Esteban Sáez-González

    Full Text Available Background: Ischemic colitis (IC is an uncommon adverse event associated with antipsychotic agents, more commonly found with phenothiazine drugs and atypical neuroleptics such as clozapine. The risk of developing ischemic colitis increases when anticholinergic drugs are associated. Case report: We report the case of a 38-year-old woman with a history of schizoaffective disorder who had been on chronic quetiapine for 3 years, and presented to the ER because of diarrhea for 5 days. Four months previously, olanzapine had been added to her psychiatric drug regimen. Physical examination revealed abdominal distension with abdominal tympanic sounds and tenderness. Emergency laboratory tests were notable for increased acute phase reagents. Tomography revealed a concentric thickening of the colonic wall in the transverse, descending and sigmoid segments, with no signs of intestinal perforation. Colonoscopy demonstrated severe mucosal involvement from the sigmoid to the hepatic flexure, with ulcerations and fibrinoid exudate. Biopsies confirmed the diagnosis of ischemic colitis. The only relevant finding in her history was the newly added drug to her baseline regimen. An adverse effect was suspected because of its anticholinergic action at the intestinal level, and the drug was withdrawn. After 6 months of follow-up clinical, laboratory and endoscopic recovery was achieved. Discussion: Antipsychotic medication should be considered as a potential cause of ischemic colitis, particularly atypical antipsychotics such as clozapine and olanzapine; despite being uncommon, this adverse event may result in high morbidity and mortality.

  1. Neuroprotection in acute ischemic stroke

    NARCIS (Netherlands)

    De Keyser, Jacques; Uyttenboogaart, Maarten; Koch, Marcus W; Elting, Jan Willem; Sulter, Geert; Vroomen, Patrick C; Luijckx, Gert Jan

    2005-01-01

    Neuroprotection of patients with acute ischemic stroke should start at the scene and continue in the ambulance with the assessment and treatment of the airway, breathing, circulation, body temperature, and blood glucose. The key goal in eligible patients should be fast vessel recanalization with int

  2. Ischemic glans penis after circumcision

    Institute of Scientific and Technical Information of China (English)

    Yuan-ShengTzeng; Shou-HungTang; EnMeng; Teng-FuLin; Guang-HuanSun

    2004-01-01

    A 33-year-old male receiving dorsal penile nerve block (DPNB) for circumcision exhibited a postoperative ischemic change over the glans penis. The event occurred nearly 24 hours after the procedure. The patient was treated with intravenous pentoxifyllin and hyperbaric oxygenation. Total reverse of the ischemia was observed. The complications associated with circumcision and DPNB were reviewed and discussed.

  3. Effects of hypoxia-inducible factor 1 on ischemic cerebrovascular disease

    Institute of Scientific and Technical Information of China (English)

    Yongjie Luo; Xiaoping Wang; Hongbin Sun

    2008-01-01

    Hypoxia-inducible factor I, a nuclear transcription factor, is induced by hypoxia. Hypoxia-inducible factor I, a heterodimeric DNA-binding protein, is composed of hypoxia-inducible factor 1α and hypoxia-inducible factor 1 β subunits, which are family members of the basic helix-loop-helix-PER, ARNT, SIM (PAS) protein. O2 concentration regulates hypoxia-inducible factor 1 activity via this subunit. Hypoxia-inducible factor 1α plays a major role in response to hypoxia and transcriptional activation, as well as in the target gene specificity of the DNA enhancer. Hypoxia-inducible factor 1β cannot be induced by hypoxia. This effect may be due to hypoxia-inducible factor 1 stability and activated conformation due to dimerization. Previous studies have shown that hypoxia-inducible factor 1 mRNA expression increases in the penumbra following ischemia/hypoxia. Hypoxia-inducible factor 1 plays an important role in brain tissue injury alter ischemia by affecting a series of target genes, elevating tolerance to hypoxia, and ensuring survival of neural cells. This article summarizes the structure, function, expression, regulatory mechanisms, biological effects, and significance of hypoxia-inducible factor 1 in patients with ischemic cerebrovascular disease. As a transcriptional activator, hypoxia- inducible factor 1 plays a key role in hypoxic responses by stabilizing the internal environment. It also has been shown to regulate the expression of several genes. The regulatory effects of hypoxia-inducible factor 1 in patients with ischemic cerebrovascular disease have been described. The present review re-examined the concept of brain protection at the level of gene regulation.

  4. Collateral flow averts hemorrhagic transformation after endovascular therapy for acute ischemic stroke.

    Science.gov (United States)

    Bang, Oh Young; Saver, Jeffrey L; Kim, Suk Jae; Kim, Gyeong-Moon; Chung, Chin-Sang; Ovbiagele, Bruce; Lee, Kwang Ho; Liebeskind, David S

    2011-08-01

    Collaterals sustain the ischemic penumbra to limit growth of the infarct core before revascularization, yet the impact of baseline collateral flow on hemorrhagic transformation (HT) after endovascular therapy remains unknown. A collaborative study from 2 stroke centers in distinct geographic regions included 222 consecutive patients who received endovascular therapy for acute cerebral ischemia. The influence of collaterals on HT was analyzed in distinct case scenarios relative to baseline collateral grade at angiography (0 to 1 versus 2 to 4) and recanalization (Thrombolysis in Myocardial Ischemia scale, 0 to 1 versus 2 to 3): good collaterals and successful recanalization (n=98), poor collaterals with successful recanalization (n=43), good collaterals and no recanalization(n=46), and poor collaterals and no recanalization (n=35). HT after endovascular therapy occurred in 103 (46.4%) patients; 42 (18.9%) were symptomatic. HT was more frequently observed in patients with poor collaterals and recanalization than in other groups (P=0.048). When revascularization was achieved, patients with poorer collaterals were more likely to have symptomatic worsening with HT (r=-0.181, P=0.032). Multiple logistic regression analysis identified aggressive treatment (OR, 2.558 for Merci clot retrieval; 95% CI, 1.153 to 5.678; OR, 3.618 for combined fibrinolytics and mechanical therapy; 95% CI, 1.551 to 8.437; and OR, 2.085 for intravenous thrombolysis before endovascular therapy; 95% CI, 1.096 to 3.969), poor collaterals and recanalization (OR, 2.666; 95% CI, 1.163 to 6.113), and serum glucose levels (OR, 1.007; 95% CI, 1.000 to 1.014) as independent predictors of HT. Angiographic grade of collateral flow strongly influences the rate of HT after therapeutic recanalization for acute ischemic stroke. Collateral status readily available from baseline angiography may therefore refine therapeutic decision-making in acute cerebral ischemia.

  5. Prediction

    CERN Document Server

    Sornette, Didier

    2010-01-01

    This chapter first presents a rather personal view of some different aspects of predictability, going in crescendo from simple linear systems to high-dimensional nonlinear systems with stochastic forcing, which exhibit emergent properties such as phase transitions and regime shifts. Then, a detailed correspondence between the phenomenology of earthquakes, financial crashes and epileptic seizures is offered. The presented statistical evidence provides the substance of a general phase diagram for understanding the many facets of the spatio-temporal organization of these systems. A key insight is to organize the evidence and mechanisms in terms of two summarizing measures: (i) amplitude of disorder or heterogeneity in the system and (ii) level of coupling or interaction strength among the system's components. On the basis of the recently identified remarkable correspondence between earthquakes and seizures, we present detailed information on a class of stochastic point processes that has been found to be particu...

  6. Risk factors for progressive ischemic stroke A retrospective analysis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    BACKGROUND: Progressive ischemic stroke has higher fatality rate and disability rate than common cerebral infarction, thus it is very significant to investigate the early predicting factors related to the occurrence of progressive ischemic stroke, thc potential pathological mechanism and the risk factors of early intervention for preventing the occurrence of progressive ischemic stroke and ameliorating its outcome.OBJECTIVE: To analyze the possible related risk factors in patients with progressive ishcemic stroke, so as to provide reference for the prevention and treatment of progressive ishcemic stroke.DESIGN: A retrospective analysis.SETTING: Department of Neurology, General Hospital of Beijing Coal Mining Group.PARTICIPANTS: Totally 280 patients with progressive ischemic stroke were selected from the Department of Neurology, General Hospital of Beijing Coal Mining Group from March 2002 to June 2006, including 192 males and 88 females, with a mean age of (62±7) years old. They were all accorded with the diagnostic standards for cerebral infarction set by the Fourth National Academic Meeting for Cerebrovascular Disease in 1995, and confired by CT or MRI, admitted within 24 hours after attack, and the neurological defect progressed gradually or aggravated in gradients within 72 hours after attack, and the aggravation of neurological defect was defined as the neurological deficit score decreased by more than 2 points. Meanwhile,200 inpatients with non-progressive ischemic stroke (135 males and 65 females) were selected as the control group.METHODS: After admission, a univariate analysis of variance was conducted using the factors of blood pressure, history of diabetes mellitus, fever, leukocytosis, levels of blood lipids, fibrinogen, blood glucose and plasma homocysteine, cerebral arterial stenosis, and CT symptoms of early infarction, and the significant factors were involved in the multivariate non-conditional Logistic regression analysis.MAIN OUTCOME MEASURES

  7. Ischemic stroke and incomplete infarction

    DEFF Research Database (Denmark)

    Garcia, Javier; Lassen, N A; Weiller, C

    1996-01-01

    The concept of selective vulnerability or selective loss o f individual neurons, with survival of glial and vascular elements as one of the consequences of a systemic ischemic-hypoxic insult (eg, transient cardiac arrest or severe hypotension), has been recognized for decades. In contrast, select......, selective neuronal death as one of the lesions that may develop in the brain after occluding an intracranial artery is an idea not readily acknowledged in the current medical literature dealing with human stroke....

  8. A Qualitative Study of Physician Perspectives on Prognostication in Neonatal Hypoxic Ischemic Encephalopathy.

    Science.gov (United States)

    Rasmussen, Lisa Anne; Bell, Emily; Racine, Eric

    2016-10-01

    Hypoxic ischemic encephalopathy is the most frequent cause of neonatal encephalopathy and yields a great degree of morbidity and mortality. From an ethical and clinical standpoint, neurological prognosis is fundamental in the care of neonates with hypoxic ischemic encephalopathy. This qualitative study explores physician perspectives about neurological prognosis in neonatal hypoxic ischemic encephalopathy. This study aimed, through semistructured interviews with neonatologists and pediatric neurologists, to understand the practice of prognostication. Qualitative thematic content analysis was used for data analysis. The authors report 2 main findings: (1) neurological prognosis remains fundamental to quality-of-life predictions and considerations of best interest, and (2) magnetic resonance imaging is presented to parents with a greater degree of certainty than actually exists. Further research is needed to explore both the parental perspective and, prospectively, the impact of different clinical approaches and styles to prognostication for neonatal hypoxic ischemic encephalopathy.

  9. Brain diffusivity in infants with hypoxic-ischemic encephalopathy following whole body hypothermia: preliminary results.

    Science.gov (United States)

    Artzi, Moran; Sira, Liat Ben; Bassan, Haim; Gross-Tsur, Varda; Berger, Irit; Marom, Ronella; Leitner, Yael; Bental, Yoram; Shiff, Yakov; Geva, Ronny; Weinstein, Maya; Bashat, Dafna Ben

    2011-10-01

    Hypoxic-ischemic encephalopathy is an important cause of neuropsychological deficits. Little is known about brain diffusivity in these infants following cooling and its potential in predicting outcome. Diffusion tensor imaging was applied to 3 groups: (1) three infants with hypoxic-ischemic encephalopathy: cooled; (2) three infants with hypoxic-ischemic encephalopathy: noncooled; and (3) four controls. Diffusivity values at the corticospinal tract, thalamus, and putamen were correlated with Apgar scores and early neurodevelopmental outcome. While cooled infants exhibited lower Apgar scores than noncooled infants, their developmental scores at a mean age of 8 months were higher. All groups differed in their diffusivity values with the cooled infants showing better values compared with the noncooled, correlating with early neurodevelopmental outcome. These preliminary results indicate that diffusion tensor imaging performed at an early age in infants with hypoxic-ischemic encephalopathy may forecast clinical outcome and support the neuroprotective effect of hypothermia treatment.

  10. Forced arterial suction thrombectomy with the penumbra reperfusion catheter in acute basilar artery occlusion: a retrospective comparison study in 2 Korean university hospitals.

    Science.gov (United States)

    Eom, Y-I; Hwang, Y-H; Hong, J M; Choi, J W; Lim, Y C; Kang, D-H; Kim, Y-W; Kim, Y-S; Kim, S Y; Lee, J S

    2014-12-01

    A performance of forced arterial suction thrombectomy was not reported for the treatment of acute basilar artery occlusion. This study compared revascularization performance between intra-arterial fibrinolytic treatment and forced arterial suction thrombectomy with a Penumbra reperfusion catheter in patients with acute basilar artery occlusion. Fifty-seven patients with acute basilar artery occlusion were treated with intra-arterial fibrinolysis (n = 25) or forced arterial suction thrombectomy (n = 32). Baseline characteristics, successful revascularization rate, and clinical outcomes were compared between the groups. Baseline characteristics, the frequency of patients receiving intravenous recombinant tissue plasminogen activator, and mean time interval between symptom onset and femoral puncture did not differ between groups. The forced arterial suction thrombectomy group had a shorter procedure duration (75.5 minutes versus 113.3 minutes, P = .016) and higher successful revascularization rate (88% versus 60%, P = .017) than the fibrinolysis group. Fair outcome, indicated by a modified Rankin Scale 0-3, at 3 months was achieved in 34% of patients undergoing forced arterial suction thrombectomy and 8% of patients undergoing fibrinolysis (P = .019), and the mortality rate was significantly higher in the fibrinolysis group (25% versus 68%, P = .001). Multiple logistic regression analysis identified the forced arterial suction thrombectomy method as an independent predictor of fair outcome with adjustment for age, sex, initial NIHSS score, and the use of intravenous recombinant tissue plasminogen activator (odds ratio, 7.768; 95% CI, 1.246-48.416; P = .028). In acute basilar artery occlusion, forced arterial suction thrombectomy demonstrated a higher revascularization rate and improved clinical outcome compared with traditional intra-arterial fibrinolysis. Further clinical trials with the newer Penumbra catheter are warranted. © 2014 by American Journal of

  11. SU-E-T-604: Penumbra Characteristics of a New InCiseâ„¢ Multileaf Collimator of CyberKnife M6â„¢ System

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, M; Jang, S; Ozhasoglu, C; Lalonde, R; Heron, D; Huq, M [University of Pittsburgh Medical Center, Pittsburgh, PA (United States)

    2015-06-15

    Purpose: The InCise™ Multileaf Collimator (MLC) of CyberKnife M6™ System has been released recently. The purpose of this study was to explore the dosimetric characteristics of the new MLC. In particular, the penumbra characteristics of MLC fields at varying locations are evaluated. Methods: EBT3-based film measurements were performed with varying MLC fields ranging from 7.5 mm to 27.5 mm. Seventeen regions of interests (ROIs) were identified for irradiation. These are regions located at the central area (denoted as reference field), at the left/right edge areas of reference open field, at an intermediate location between central and edge area. Single beam treatment plans were designed by using the MultiPlan and was delivered using the Blue Phantom. Gafchromic films were irradiated at 1.5 cm depth in the Blue Phantom and analyzed using the Film Pro software. Variation of maximum dose, penumbra of MLC-defined fields, and symmetry/flatness were calculated as a function of locations of MLC fields. Results: The InCise™ MLC System showed relatively consistent dose distribution and penumbra size with varying locations of MLC fields. The measured maximum dose varied within 5 % at different locations compared to that at the central location and agreed with the calculated data well within 2%. The measured penumbrae were in the range of 2.9 mm and 3.7 mm and were relatively consistent regardless of locations. However, dose profiles in the out-of-field and in-field regions varied with locations and field sizes. Strong variation was seen for all fields located at 55 mm away from the central field. The MLC leakage map showed that the leakage is dependent on position. Conclusion: The size of penumbra and normalized maximum dose for MLC-defined fields were consistent in different regions of MLC. However, dose profiles in the out-field region varied with locations and field sizes.

  12. Comparison of eicosapentaenoic acid concentrations in plasma between patients with ischemic stroke and control subjects.

    Science.gov (United States)

    Ikeya, Yoshimori; Fukuyama, Naoto; Kitajima, Waichi; Ogushi, Yoichi; Mori, Hidezo

    2013-01-01

    ω-3 fatty acids, including eicosapentaenoic acid (EPA), prevent ischemic stroke. However, the clinical importance of EPA for ischemic stroke and its subtype has not been fully elucidated. In a cross-sectional study, we determined whether ω-3 fatty acids were predictive factors for ischemic stroke. We compared common clinical parameters among 65 patients with ischemic stroke and 65 control subjects. The parameters included blood chemistry data; concentrations of EPA, docosahexaenoic acid, and arachidonic acid (AA); EPA/AA ratio; smoking; alcohol intake; fish consumption more than four times per week; and the incidence of underlying diseases. The comparisons were performed using the Mann-Whitney U test, and multiple logistic regression analysis was applied to the significant factors in the non-parametric test. We also applied the same approach to the ischemic stroke subtypes, cardioembolism and large-artery atherosclerosis. In the multiple logistic regression analysis after the Mann-Whitney U test, a lower EPA concentration was one of the significant risk factors for ischemic stroke, as were a lower body mass index, lower high-density lipoprotein cholesterol, and smoking (sensitivity 0.846, specificity 0.831, positive predictive value 0.833). In the analysis of subtypes, a lower EPA/AA ratio and a lower body mass index were the significant risk factors for cardioembolism (sensitivity 0.800, specificity 0.733, positive predictive value 0.750). However, large-artery atherosclerosis was not related to the EPA concentration or the EPA/AA ratio. In this study, the plasma EPA concentration and the EPA/AA ratio were potential predictive risk factors for ischemic stroke, especially for cardioembolism. Further prospective studies are necessary. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Diffusion weighted imaging and estimation of prognosis using apparent diffusion coefficient measurements in ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Gonen, Korcan Aysun, E-mail: aysunbalc@yahoo.com [Department of Radiology, State Hospital, Eski Cami district, Hastane street, N:1, 59300, Tekirdag (Turkey); Simsek, Mehmet Masum, E-mail: radyoloji@haydapasanumune.gov.tr [Department of Radiology, Haydarpasa Numune Training and Research Hospital, Tibbiye street, Uskudar 34200, Istanbul (Turkey)

    2010-11-15

    Objective: Estimation of the prognosis of infarction by using diffusion weighted imaging (DWI) and quantitative apparent diffusion coefficient (ADC) measurements. Methods: 23 patients having acute stroke symptoms with verified infarction in magnetic resonance imaging (MRI) were included in this study. Their MRI studies were performed between 6 and 12 h after the onset of their symptoms and were repeated on the fifth day. The infarction volumes were calculated by using DWI and the patients were divided into two groups as the ones having an expansion in the infarction area (group 1, n = 16) and the others having no expansion in the infarction area (group 2, n = 7). Quantitative ADC values were estimated. The groups were compared in terms of the ADC values on ADC maps obtained from DWI, performed during the between 6 and 12 h from the onset of the symptoms, referring to the core of the infarction (ADC{sub IC}), ischemic penumbra (ADC{sub P}) and the nonischemic parenchymal tissue (ADC{sub N}). P values < 0.05 were accepted to be statistically significant. Results: During the between 6 and 12 h mean infarction volume calculated by DWI was 23.3 cm{sup 3} for group 1 patients (ranging from 1.1 to 68.6) and this was found to be 40.3 cm{sup 3} (ranging from 1.8 to 91.5) on the fifth day. For the group 2 patients these values were found to be 42.1 cm{sup 3} (ranging from 1 to 94.7) and 41.9 (ranging from 1 to 94.7) for the same intervals respectively. A significant statistical result was failed to be demonstrated between the mean ADC{sub IC} and ADC{sub N} values (p = 0.350 and p = 0.229 respectively). However the comparison of the ADC{sub P} values between the groups was found to be highly significant (p < 0.001). When the differences between the ADC{sub P} and ADC{sub IC} and ADC{sub N} and ADC{sub P} were compared the results proved to be statistically significant (p = 0.038 and p < 0.001 respectively). Conclusions: We believe that ADC results that would be obtained from

  14. Angiogenesis, neurogenesis and neuroplasticity in ischemic stroke.

    Science.gov (United States)

    Font, M Angels; Arboix, Adriá; Krupinski, Jerzy

    2010-08-01

    Only very little is know about the neurovascular niche after cardioembolic stroke. Three processes implicated in neurorepair: angiogenesis, neurogenesis and synaptic plasticity, would be naturally produced in adult brains, but also could be stimulated through endogen neurorepair phenomena. Angiogenesis stimulation generates new vessels with the aim to increase collateral circulation. Neurogenesis is controlled by intrinsic genetic mechanisms and growth factors but also ambiental factors are important. The leading process of the migrating neural progenitor cells (NPCs) is closely associated with blood vessels, suggesting that this interaction provides directional guidance to the NPCs. These findings suggest that blood vessels play an important role as a scaffold for NPCs migration toward the damaged brain region. DNA microarray technology and blood genomic profiling in human stroke provided tools to investigate the expression of thousands of genes. Critical comparison of gene expression profiles after stroke in humans with those in animal models should lead to a better understanding of the pathophysiology of brain ischaemia. Probably the most important part of early recovery after stroke is limited capacity of penumbra/infarct neurones to recover. It became more clear in the last years, that penumbra is not just passively dying over time but it is also actively recovering. This initial plasticity in majority contributes towards later neurogenesis, angiogenesis and final recovery. Penumbra is a principal target in acute phase of stroke. Thus, the origin of newly formed vessels and the pathogenic role of neovascularization and neurogenesis are important unresolved issues in our understanding of the mechanisms after stroke. Biomaterials for promoting brain protection, repair and regeneration are new hot target. Recently developed biomaterials can enable and increase the target delivery of drugs or therapeutic proteins to the brain, allow cell or tissue transplants to

  15. Risk factors for ischemic stroke and transient ischemic attack in patients under age 50

    NARCIS (Netherlands)

    Janssen, A.W.M.; Leeuw, F.E. de; Janssen, M.C.H.

    2011-01-01

    To analyze risk factors for ischemic stroke and transient ischemic attack (TIA) in young adults under the age of 50. To make recommendations for additional research and practical consequences. From 97 patients with ischemic stroke or TIA under the age of 50, classical cardiovascular risk factors, co

  16. The Predictive Value of Combining Umbilical Arterial and Radial Arterial pH for Neonatal Hypoxic Ischemic Encephalopathy%脐带血联合动脉血pH值对新生儿缺血缺氧性脑病的预测价值

    Institute of Scientific and Technical Information of China (English)

    郭晓辉; 李华英; 夏俊霞; 沙文琼; 陈淑芳

    2011-01-01

    目的 探讨脐带血联合动脉血pH值对新生儿缺血缺氧性脑病(HIE)的预测价值.方法 选取2009年4月至2011年1月在深圳市人民医院分娩的无严重畸形的7 456例活产婴儿作为研究对象,对其脐动脉血pH值与新生儿缺血缺氧性脑病的相关性进行分析,并随机选择481例新生儿于出生后1h行桡动脉血气分析.结果 7 456例脐动脉血pH为7.10~7.42.以脐带血pH<7.10为指标预测新生儿HIE的阳性预测值为35.57%,敏感性42.06%.脐带血联合出生后1h动脉血pH值预测HIE的敏感性为60.00%,阳性预测值71.79%.联合检测与单项检测临床符合率比较,差异有统计学意义(P<0.01).结论 脐带血pH<7.10且出生1h动脉血pH<7.3对新生儿缺血缺氧性脑病有预测意义.脐动脉血pH<7.10的新生儿应常规于出生后复查桡动脉血pH值.%Objective To study the predictive value of combining radial arterial blood and umbilical arterial blood gas analysis for hypoxic ischemic encephalopathy (HIE). Methods 7 456 neonates without severe deformity,bom in Shenzhen People's Hospital from April 2009 to January 2011, were recruited into our research. The correlation between umbilical arterial blood gas analysis and neonatal hypoxic ischemic encephalopathy were analyzed. 481 cases were randomly selected for radial arterial blood gas analysis an hour after birth. Results The pH values of umbilical arterial blood ranged from 7.10 to 7.42. There was a significant correlation between HIE and the pH value of umbilical arterial blood (P < 0.05). Taken pH<7.10 as an indicator to assess neonatal HIE,the positive predictive value and sensitivity were 35.5% and 42.06%, respectively. The positive predictive value and sensitivity of combining radial arterial with umbilical arterial blood gas analysis were 71.79% and 60.00%, respectively. The difference in clinical coincidence rates between combined test and single test was statistically significant (P < 0

  17. Intracranial arterial calcification is highly prevalent in hemodialysis patients but does not associate with acute ischemic stroke.

    Science.gov (United States)

    Power, Albert; Chan, Kakit; Haydar, Ali; Hamady, Mohamed; Cairns, Tom; Taube, David; Duncan, Neill

    2011-04-01

    Intracranial arterial calcification (IAC) is associated with ischemic stroke in the general population but this relationship has not been examined in hemodialysis patients. We examined the factors associated with IAC and its relationship with acute ischemic stroke in this population. We retrospectively studied 490 head computed tomographic scans from 2225 hemodialysis patients presenting with neurological symptoms at our center (October 2005-May 2009). Intracranial arterial calcification was graded using a validated scoring system. Multivariate regression was used to examine the factors associated with the presence of IAC, its severity, and its ability to predict acute ischemic stroke. Weibull's survival models analyzed the relationship between IAC severity and survival. Ninety-five percent of patients with ischemic stroke had IAC vs. 83% in the nonstroke group (P=0.02). Intracranial arterial calcification severity increased with age (Pacute ischemic stroke (P=0.05) on logistic regression analysis. High-grade and not low-grade IAC was associated with worse survival (P=0.008). Intracranial arterial calcification is highly prevalent in hemodialysis patients, especially in those with acute ischemic stroke. Its severity is prognostically significant and associated with risk factors for vascular calcification and may confer a greater risk of acute ischemic stroke. The mechanisms underlying the high incidence of ischemic stroke in this patient group require further comprehensive study. © 2011 The Authors. Hemodialysis International © 2011 International Society for Hemodialysis.

  18. Diabetes and ischemic heart disease

    DEFF Research Database (Denmark)

    Bergmann, Natasha; Ballegaard, Søren; Holmager, Pernille

    2014-01-01

    The aim of this study was to test i) whether patients having diabetes and ischemic heart disease (IHD), i.e., patients suffering from two chronic diseases, demonstrate a higher degree of chronic stress when compared with patients suffering from IHD alone, and ii) whether suffering from the two...... chronic diseases results in an elevation in specific elements of the chronic stress concept. A total of 361 participants with IHD were included, of whom 47 suffered from concomitant diabetes. Stress was measured by pressure pain sensitivity (PPS) and by the following questionnaires: the Major Depression...

  19. Diabetes and poor outcomes within 6 months after acute ischemic stroke: the China National Stroke Registry.

    Science.gov (United States)

    Jia, Qian; Zhao, Xingquan; Wang, Chunxue; Wang, Yilong; Yan, Yu; Li, Hao; Zhong, Liyong; Liu, Liping; Zheng, Huaguang; Zhou, Yong; Wang, Yongjun

    2011-10-01

    Diabetes mellitus (DM) is an independent risk factor for ischemic stroke. However, controversy exists with regard to the impact of DM on prognosis after ischemic stroke in the Chinese population. We investigated the associations between DM and death, dependency, and stroke recurrence in patients after ischemic stroke onset in a nationwide, prospective registry, the China National Stroke Registry. The China National Stroke Registry consecutively recruited patients hospitalized for acute ischemic stroke in 2007 to 2008 and who were prospectively followed up for clinical and functional outcomes (death, dependency, and stroke recurrence) at 3 and 6 months after disease onset. Multivariable logistic regression was performed to analyze the association between DM and stroke outcomes after adjusting for potential confounding including age, sex, National Institutes of Health Stroke Scale score, glucose level at admission, hypertension, coronary heart disease, smoking, urinary tract infection, and other factors. DM was identified in 3483 (27.0%) of stroke patients. Compared with stroke patients without DM, patients with DM had a significantly higher incidence of death or dependency and of recurrent stroke at 3 and 6 months after stroke onset. DM was an independent risk factor for death or dependency (adjusted odds ratio=1.23; 95% confidence interval, 1.10 to 1.37) in patients with ischemic stroke at 6 months after onset. DM independently predicted poor outcomes in Chinese patients after acute ischemic stroke.

  20. Remote Ischemic Conditioning: Its Benefits and Limitations.

    Science.gov (United States)

    Kloner, Robert A

    2016-03-01

    This editorial describes benefits and limitations of remote ischemic conditioning. Remote ischemic conditioning was shown to reduce myocardial intact size in at least 4 sizeable clinical trials of acute myocardial infarction. It was not effective in recent studies of cardiac surgery. Reasons for these differences are discussed.

  1. Genetically determined coagulation disorders in ischemic stroke

    NARCIS (Netherlands)

    M.P.J. van Goor (Marie-Louise)

    2004-01-01

    textabstractThe aim of the research described in this thesis was to investigate the role of genetically determined coagulation disorders in ischemic stroke. We therefore performed several retrospective studies and one prospective case-control study of patients with recent ischemic stroke (the COCOS

  2. Persistent cognitive impairment after transient ischemic attack

    NARCIS (Netherlands)

    Rooij, F.G. van; Schaapsmeerders, P.; Maaijwee, N.A.; Duijnhoven, D.A. van; Leeuw, F.E. de; Kessels, R.P.; Dijk, E.J. van

    2014-01-01

    BACKGROUND AND PURPOSE: By definition, the symptoms of a transient ischemic attack (TIA) subside completely within 24 hours. Imaging studies show signs of persistent ischemic tissue damage in a substantial amount of patients with TIA. Cerebral infarction can cause permanent cognitive impairment. Whe

  3. Persistent Cognitive Impairment After Transient Ischemic Attack

    NARCIS (Netherlands)

    Rooij, F.G. van; Schaapsmeerders, P.; Maaijwee, N.A.M.M.; Duijnhoven, D.A. van; de Leeuw, F.E.; Kessels, R.P.C.; Dijk, E.J. van

    2014-01-01

    Background and Purpose—By definition, the symptoms of a transient ischemic attack (TIA) subside completely within 24 hours. Imaging studies show signs of persistent ischemic tissue damage in a substantial amount of patients with TIA. Cerebral infarction can cause permanent cognitive impairment. Whet

  4. Persimmon leaf flavonoid promotes brain ischemic tolerance**

    Institute of Scientific and Technical Information of China (English)

    Mingsan Miao; Xuexia Zhang; Ming Bai; Linan Wang

    2013-01-01

    Persimmon leaf flavonoid has been shown to enhance brain ischemic tolerance in mice, but its mechanism of action remains unclear. The bilateral common carotid arteries were occluded using a micro clip to block blood flow for 10 minutes. After 10 minutes of ischemic preconditioning, 200, 100, and 50 mg/kg persimmon leaf flavonoid or 20 mg/kg ginaton was intragastrical y administered per day for 5 days. At 1 hour after the final administration, ischemia/reperfusion models were estab-lished by blocking the middle cerebral artery for 2 hours. At 24 hours after model establishment, compared with cerebral ischemic rats without ischemic preconditioning or drug intervention, plasma endothelin, thrombomodulin and von Wil ebrand factor levels significantly decreased and intercel-lular adhesion molecule-1 expression markedly reduced in brain tissue from rats with ischemic pre-conditioning. Simultaneously, brain tissue injury reduced. Ischemic preconditioning combined with drug exposure noticeably improved the effects of the above-mentioned indices, and the effects of 200 mg/kg persimmon leaf flavonoid were similar to 20 mg/kg ginaton treatment. These results indicate that ischemic preconditioning produces tolerance to recurrent severe cerebral ischemia. However, persimmon leaf flavonoid can elevate ischemic tolerance by reducing inflammatory reactions and vascular endothelial injury. High-dose persimmon leaf flavonoid showed an identical effect to ginaton.

  5. Genetic Factors Influencing Coagulation Factor XIII B-Subunit Contribute to Risk of Ischemic Stroke.

    Science.gov (United States)

    Hanscombe, Ken B; Traylor, Matthew; Hysi, Pirro G; Bevan, Stephen; Dichgans, Martin; Rothwell, Peter M; Worrall, Bradford B; Seshadri, Sudha; Sudlow, Cathie; Williams, Frances M K; Markus, Hugh S; Lewis, Cathryn M

    2015-08-01

    Abnormal coagulation has been implicated in the pathogenesis of ischemic stroke, but how this association is mediated and whether it differs between ischemic stroke subtypes is unknown. We determined the shared genetic risk between 14 coagulation factors and ischemic stroke and its subtypes. Using genome-wide association study results for 14 coagulation factors from the population-based TwinsUK sample (N≈2000 for each factor), meta-analysis results from the METASTROKE consortium ischemic stroke genome-wide association study (12 389 cases, 62 004 controls), and genotype data for 9520 individuals from the WTCCC2 ischemic stroke study (3548 cases, 5972 controls-the largest METASTROKE subsample), we explored shared genetic risk for coagulation and stroke. We performed three analyses: (1) a test for excess concordance (or discordance) in single nucleotide polymorphism effect direction across coagulation and stroke, (2) an estimation of the joint effect of multiple coagulation-associated single nucleotide polymorphisms in stroke, and (3) an evaluation of common genetic risk between coagulation and stroke. One coagulation factor, factor XIII subunit B (FXIIIB), showed consistent effects in the concordance analysis, the estimation of polygenic risk, and the validation with genotype data, with associations specific to the cardioembolic stroke subtype. Effect directions for FXIIIB-associated single nucleotide polymorphisms were significantly discordant with cardioembolic disease (smallest P=5.7×10(-04)); the joint effect of FXIIIB-associated single nucleotide polymorphisms was significantly predictive of ischemic stroke (smallest P=1.8×10(-04)) and the cardioembolic subtype (smallest P=1.7×10(-04)). We found substantial negative genetic covariation between FXIIIB and ischemic stroke (rG=-0.71, P=0.01) and the cardioembolic subtype (rG=-0.80, P=0.03). Genetic markers associated with low FXIIIB levels increase risk of ischemic stroke cardioembolic subtype. © 2015 The

  6. Incidence, trends, and predictors of ischemic stroke 30 days after an acute myocardial infarction.

    Science.gov (United States)

    Kajermo, Ulf; Ulvenstam, Anders; Modica, Angelo; Jernberg, Tomas; Mooe, Thomas

    2014-05-01

    Ischemic stroke is a known complication of acute myocardial infarction (AMI). Treatment of AMI has undergone great changes in recent years. We aimed to investigate whether changes in treatment corresponded to a lower incidence of ischemic stroke and which factors predicted ischemic stroke after AMI. Data were taken from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions. Patients with their first registered AMI between 1998 and 2008 were included. To identify ischemic strokes, we used the Swedish national patient register. To study a potential trend in the incidence of ischemic stroke after AMI over time, we divided the patient population into 5 time periods. Event-free survival was studied by Kaplan-Meier analysis. Cox proportional hazards regression model was used to identify stroke predictors. Of 173,233 patients with AMI, 3571 (2.1%) developed ischemic stroke within 30 days. The incidence of ischemic stroke was significantly lower during the years 2007 to 2008 compared with 1998 to 2000, with respective rates of 2.0% and 2.2% (P=0.02). Independent predictors of an increased risk of stroke were age, female sex, prior stroke, diabetes mellitus, atrial fibrillation, clinical signs of heart failure in hospital, ST-segment-elevation myocardial infarction, coronary artery bypass grafting, and angiotensin-converting enzyme inhibitor treatment at discharge. Percutaneous coronary intervention, fibrinolysis, acetylsalicylic acid, statins, and P2Y12 inhibitors were predictors of reduced risk of stroke. The incidence of ischemic stroke within 30 days of an AMI has decreased during the period 1998 to 2008. This decrease is associated with increased use of acetylsalicylic acid, P2Y12 inhibitors, statins, and percutaneous coronary intervention.

  7. [Acute ischemic proctitis following an epileptic attack

    DEFF Research Database (Denmark)

    Klintmann, C.K.; Hillingso, J.G.; Glenthøj, Andreas

    2008-01-01

    Acute ischemic proctitis is a rare diagnosis mainly because the rectum is supplied by an extensive arterial network. Consequently, in more than 90% of patients with ischemic colitis the rectum is spared. Previously reported cases are related to severe vascular insufficiency of the rectal circulat......Acute ischemic proctitis is a rare diagnosis mainly because the rectum is supplied by an extensive arterial network. Consequently, in more than 90% of patients with ischemic colitis the rectum is spared. Previously reported cases are related to severe vascular insufficiency of the rectal...... circulation caused by systemic atherosclerosis, usually following aortic or aortoiliac operations. We report one case of acute ischemic proctitis following an epileptic attack Udgivelsesdato: 2008/9/29...

  8. Interleukin-1α expression precedes IL-1β after ischemic brain injury and is localised to areas of focal neuronal loss and penumbral tissues

    Directory of Open Access Journals (Sweden)

    Luheshi Nadia M

    2011-12-01

    Full Text Available Abstract Background Cerebral ischemia is a devastating condition in which the outcome is heavily influenced by inflammatory processes, which can augment primary injury caused by reduced blood supply. The cytokines interleukin-1α (IL-1α and IL-1β are key contributors to ischemic brain injury. However, there is very little evidence that IL-1 expression occurs at the protein level early enough (within hours to influence brain damage after stroke. In order to determine this we investigated the temporal and spatial profiles of IL-1α and IL-1β expression after cerebral ischemia. Findings We report here that in mice, as early as 4 h after reperfusion following ischemia induced by occlusion of the middle cerebral artery, IL-1α, but not IL-1β, is expressed by microglia-like cells in the ischemic hemisphere, which parallels an upregulation of IL-1α mRNA. 24 h after ischemia IL-1α expression is closely associated with areas of focal blood brain barrier breakdown and neuronal death, mostly near the penumbra surrounding the infarct. The sub-cellular distribution of IL-1α in injured areas is not uniform suggesting that it is regulated. Conclusions The early expression of IL-1α in areas of focal neuronal injury suggests that it is the major form of IL-1 contributing to inflammation early after cerebral ischemia. This adds to the growing body of evidence that IL-1α is a key mediator of the sterile inflammatory response.

  9. Swallowing disorders after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Gabriela Camargo Remesso

    2011-10-01

    Full Text Available OBJECTIVE: To investigate occurrences of swallowing disorders after ischemic stroke. METHOD: This was a retrospective study on 596 medical files. The inclusion criterion was that the patients needed to have been hospitalized with a diagnosis of ischemic stroke; the exclusion criteria were the presence of associated cardiac problems and hospital stay already more than 14 days. RESULTS: 50.5% were men and 49.5% women; mean age 65.3 years (SD=±11.7 (p<0.001. Among the risk factors, 79.4% had hypertension, 36.7% had diabetes (p<0.001 and 42.7% were smokers. 13.3% of the patients died. Swallowing disorders occurred in 19.6%, among whom 91.5% had mild difficulty and 8.5% had severe difficulty. 87.1% had spontaneous recovery after a mean of 2.4 months. A lesion in the brainstem region occurred in 6.8% (p<0.001. CONCLUSION: Swallowing disorders occurred in almost 20% of the population and most of the difficulty in swallowing found was mild. The predictors for swallowing disorders were older age, diabetes mellitus and lesions in the brainstem region.

  10. Asymmetric Dimethyarginine as Marker and Mediator in Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Karin Weissenborn

    2012-11-01

    Full Text Available Asymmetric dimethylarginine (ADMA, an endogenous nitric oxide synthase (NOS inhibitor, is known as mediator of endothelial cell dysfunction and atherosclerosis. Circulating ADMA levels are correlated with cardiovascular risk factors such as hypercholesterolemia, arterial hypertension, diabetes mellitus, hyperhomocysteinemia, age and smoking. Accordingly, clinical studies found evidence that increased ADMA levels are associated with a higher risk of cerebrovascular events. After the acute event of ischemic stroke, levels of ADMA and its analog symmetric dimethylarginine (SDMA are elevated through augmentation of protein methylation and oxidative stress. Furthermore, cleavage of ADMA through dimethylarginine dimethylaminohydrolases (DDAHs is reduced. This increase of dimethylarginines might be predictive for adverse clinical outcome. However, the definite role of ADMA after acute ischemic stroke still needs to be clarified. On the one hand, ADMA might contribute to brain injury by reduction of cerebral blood flow. On the other hand, ADMA might be involved in NOS-induced oxidative stress and excitotoxic neuronal death. In the present review, we highlight the current knowledge from clinical and experimental studies on ADMA and its role for stroke risk and ischemic brain injury in the hyperacute stage after stroke. Finally, further studies are warranted to unravel the relevance of the close association of dimethylarginines with stroke.

  11. Ischemic preconditioning reduces ischemic brain injury by suppressing nuclear factor kappa B expression and neuronal apoptosis

    Institute of Scientific and Technical Information of China (English)

    Songsheng Shi; Weizhong Yang; Xiankun Tu; Chunmei Chen; Chunhua Wang

    2013-01-01

    Ischemic stroke induces a series of complex pathophysiological events including blood-brain barrier disruption, inflammatory response and neuronal apoptosis. Previous studies demonstrate that ischemic preconditioning attenuates ischemic brain damage via inhibiting blood-brain barrier disruption and the inflammatory response. Rats underwent transient (15 minutes) occlusion of the bilateral common carotid artery with 48 hours of reperfusion, and were subjected to permanent middle cerebral artery occlusion. This study explored whether ischemic preconditioning could reduce ischemic brain injury and relevant molecular mechanisms by inhibiting neuronal apoptosis. Results found that at 72 hours following cerebral ischemia, myeloperoxidase activity was enhanced, malondialdehyde levels increased, and neurological function was obviously damaged. Simultaneously, neuronal apoptosis increased, and nuclear factor-κB and cleaved caspase-3 expression was significantly increased in ischemic brain tissues. Ischemic preconditioning reduced the cerebral ischemia-induced inflammatory response, lipid peroxidation, and neurological function injury. In addition, ischemic preconditioning decreased nuclear factor-κB p65 and cleaved caspase-3 expression. These results suggested that ischemic preconditioning plays a protective effect against ischemic brain injury by suppressing the inflammatory response, reducing lipid peroxidation, and neuronal apoptosis via inhibition of nuclear factor-κB and cleaved caspase-3 expression.

  12. Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion

    Science.gov (United States)

    Lin, Lei-Lei; Dong, Yan-Min; Zong, Yao; Zheng, Qi-Shan; Fu, Yue; Yuan, Yong-Guang; Huang, Xia; Qian, Garrett; Gao, Qian-Ying

    2016-01-01

    AIM To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion (BRVO). METHODS Fifty BRVO eyes were divided into ischemic (n=26) and non-ischemic (n=24) groups, based on fundus fluorescein angiography. Healthy individuals (n=52 and n=48, respectively) were also recruited as controls for the two groups. The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups. RESULTS In the ischemic BRVO group, the occluded arterioles oxygen saturation (SaO2-A, 106.0%±14.3%), instead of the occluded venule oxygen saturation (SaO2-V, 60.8%±9.4%), showed increases when compared with those in the same quadrant vessels (SaO2-A, 86.1%±16.5%) in the contralateral eyes (Pcentral vessels showed similar trends with those of the occluded vessels. In the non-ischemic BRVO group, the occluded and central SaO2-V and SaO2-A showed no significant changes. In both the ischemic and non-ischemic BRVOs, the central SaO2-A was significantly increased when compared to healthy individuals. CONCLUSION Obvious changes in the occluded and central SaO2-A were found in the ischemic BRVO group, indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO. PMID:26949618

  13. Rare variants in ischemic stroke: an exome pilot study.

    Directory of Open Access Journals (Sweden)

    John W Cole

    Full Text Available The genetic architecture of ischemic stroke is complex and is likely to include rare or low frequency variants with high penetrance and large effect sizes. Such variants are likely to provide important insights into disease pathogenesis compared to common variants with small effect sizes. Because a significant portion of human functional variation may derive from the protein-coding portion of genes we undertook a pilot study to identify variation across the human exome (i.e., the coding exons across the entire human genome in 10 ischemic stroke cases. Our efforts focused on evaluating the feasibility and identifying the difficulties in this type of research as it applies to ischemic stroke. The cases included 8 African-Americans and 2 Caucasians selected on the basis of similar stroke subtypes and by implementing a case selection algorithm that emphasized the genetic contribution of stroke risk. Following construction of paired-end sequencing libraries, all predicted human exons in each sample were captured and sequenced. Sequencing generated an average of 25.5 million read pairs (75 bp×2 and 3.8 Gbp per sample. After passing quality filters, screening the exomes against dbSNP demonstrated an average of 2839 novel SNPs among African-Americans and 1105 among Caucasians. In an aggregate analysis, 48 genes were identified to have at least one rare variant across all stroke cases. One gene, CSN3, identified by screening our prior GWAS results in conjunction with our exome results, was found to contain an interesting coding polymorphism as well as containing excess rare variation as compared with the other genes evaluated. In conclusion, while rare coding variants may predispose to the risk of ischemic stroke, this fact has yet to be definitively proven. Our study demonstrates the complexities of such research and highlights that while exome data can be obtained, the optimal analytical methods have yet to be determined.

  14. The Prognostic Values of Leukocyte Rho Kinase Activity in Acute Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Cheng-I. Cheng

    2014-01-01

    Full Text Available Objective. It has been reported that leukocyte ROCK activity is elevated in patients after ischemic stroke, but it is unclear whether leukocyte ROCK activity is associated with clinical outcomes following acute stroke events. The objective of this study is to investigate if leukocyte ROCK activity can predict the outcomes in patients with acute ischemic stroke. Materials and Methods. We enrolled 110 patients of acute ischemic stroke and measured the leukocyte ROCK activity and plasma level of inflammatory cytokines to correlate the clinical outcomes of these patients. Results. The leukocyte ROCK activity at 48 hours after admission in acute ischemic stroke patients was higher as compared to a risk-matched population. The leukocyte ROCK activity significantly correlated with National Institute of Health Stroke Scale (NIHSS difference between admission and 90 days after stroke event. Kaplan-Meier survival estimates showed lower stroke-free survival during follow-up period in patients with high leukocyte ROCK activity or plasma hsCRP level. Leukocyte ROCK activity independently predicted the recurrent stroke in patients with atherosclerotic stroke. Conclusions. This study shows elevated leukocyte ROCK activity in patients with ischemic stroke as compared to risk-matched subjects and is an independent predictor for recurrent stroke.

  15. Immune mechanisms in cerebral ischemic tolerance

    Directory of Open Access Journals (Sweden)

    Lidia eGarcia-Bonilla

    2014-03-01

    Full Text Available Stressor-induced tolerance is a central mechanism in the response of bacteria, plants, and animals to potentially harmful environmental challenges. This response is characterized by immediate changes in cellular metabolism and by the delayed transcriptional activation or inhibition of genetic programs that are not generally stressor specific (cross-tolerance. These programs are aimed at countering the deleterious effects of the stressor. While induction of this response (preconditioning can be established at the cellular level, activation of systemic networks is essential for the protection to occur throughout the organs of the body. This is best signified by the phenomenon of remote ischemic preconditioning, whereby application of ischemic stress to one tissue or organ induces ischemic tolerance in remote organs through humoral, cellular and neural signaling. The immune system is an essential component in cerebral ischemic tolerance acting simultaneously both as mediator and target. This dichotomy is based on the fact that activation of inflammatory pathways is necessary to establish ischemic tolerance and that ischemic tolerance can be, in part, attributed to a subdued immune activation after index ischemia. Here we describe the components of the immune system required for induction of ischemic tolerance and review the mechanisms by which a reprogrammed immune response contributes to the neuroprotection observed after preconditioning. Learning how local and systemic immune factors participate in endogenous neuroprotection could lead to the development of new stroke therapies.

  16. Electroacupuncture Pretreatment Attenuates Cerebral Ischemic Injury via Notch Pathway-Mediated Up-Regulation of Hypoxia Inducible Factor-1α in Rats.

    Science.gov (United States)

    Zhao, Yu; Deng, Bin; Li, Yichong; Zhou, Lihua; Yang, Lei; Gou, Xingchun; Wang, Qiang; Chen, Guozhong; Xu, Hao; Xu, Lixian

    2015-11-01

    We have reported electroacupuncture (EA) pretreatment induced the tolerance against focal cerebral ischemia through activation of canonical Notch pathway. However, the underlying mechanisms have not been fully understood. Evidences suggest that up-regulation of hypoxia inducible factor-1α (HIF-1α) contributes to neuroprotection against ischemia which could interact with Notch signaling pathway in this process. Therefore, the current study is to test that up-regulation of HIF-1α associated with Notch pathway contributes to the neuroprotection of EA pretreatment. Sprague-Dawley rats were treated with EA at the acupoint "Baihui (GV 20)" 30 min per day for successive 5 days before MCAO. HIF-1α levels were measured before and after reperfusion. Then, HIF-1α antagonist 2ME2 and γ-secretase inhibitor MW167 were used. Neurologic deficit scores, infarction volumes, neuronal apoptosis, and Bcl2/Bax were evaluated. HIF-1α and Notch1 intracellular domain (NICD) were assessed. The results showed EA pretreatment enhanced the neuronal expression of HIF-1α, reduced infarct volume, improved neurological outcome, inhibited neuronal apoptosis, up-regulated expression of Bcl-2, and down-regulated expression of Bax after reperfusion in the penumbra, while the beneficial effects were attenuated by 2ME2. Furthermore, intraventricular injection with MW167 efficiently suppressed both up-regulation of NICD and HIF-1α after reperfusion. However, administration with 2ME2 could only decrease the expression of HIF-1α in the penumbra. In conclusion, EA pretreatment exerts neuroprotection against ischemic injury through Notch pathway-mediated up-regulation of HIF-1α.

  17. [Cortical spreading depolarization phenomena in patients with traumatic and ischemic brain injuries. Results of a pilot study].

    Science.gov (United States)

    Sueiras, M; Sahuquillo, J; García-López, B; Sánchez-Guerrero, Á; Poca, M A; Santamarina, E; Riveiro, M; Fabricius, M; Strong, A J

    2014-10-01

    To determine the frequency and duration of cortical spreading depolarization (CSD) and CSD-like episodes in patients with traumatic brain injury (TBI) and malignant middle cerebral artery infarction (MMCAI) requiring craniotomy. A descriptive observational study was carried out during 19 months. Neurocritical patients. Sixteen patients were included: 9 with MMCAI and 7 with moderate or severe TBI, requiring surgical treatment. A 6-electrode subdural electrocorticographic (ECoG) strip was placed onto the perilesional cortex. An analysis was made of the time profile and the number and duration of CSD and CSD-like episodes recorded from the ECoGs. Of the 16 patients enrolled, 9 presented episodes of CSD or CSD-like phenomena, of highly variable frequency and duration. Episodes of CSD and CSD-like phenomena are frequently detected in the ischemic penumbra and/or traumatic cortical regions of patients with MMCAI who require decompressive craniectomy or of patients with contusional TBI. Copyright © 2013 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.

  18. Timing of ischemic onset estimated from the electrocardiogram is better than historical timing for predicting outcome after reperfusion therapy for acute anterior myocardial infarction: a DANish trial in Acute Myocardial Infarction 2 (DANAMI-2) substudy

    DEFF Research Database (Denmark)

    Sejersten, Maria; Ripa, Rasmus S; Grande, Peer

    2007-01-01

    BACKGROUND: Acute treatment strategy and subsequently prognosis are influenced by the duration of ischemia in patients with ST-elevation acute myocardial infarction (AMI). However, timing of ischemia may be difficult to access by patient history (historical timing) alone. We hypothesized...... that an electrocardiographic acuteness score is better than historical timing for predicting myocardial salvage and prognosis in patients with anterior AMI treated with fibrinolysis or primary percutaneous coronary intervention. METHODS: One hundred seventy-five patients with anterior infarct without electrocardiogram (ECG...... the Aldrich score to determine the initially predicted myocardial infarct size and the Selvester score to determine the final QRS-estimated myocardial infarct size. RESULTS: The mean amount of myocardium salvage depended on ECG timing (43% [+/-38%] for "early" vs 1% [+/-56%] for "late"; P

  19. Unilateral anterior ischemic optic neuropathy

    DEFF Research Database (Denmark)

    Herbst, Kristina; Sander, Birgit; Lund-Andersen, Henrik

    2013-01-01

    The intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin, which is sensitive to blue light. Previous chromatic pupillometry studies have shown that the post-illumination response is considered an indicator of the melanopsin activation. The aim......-affected eyes, compared with the non-affected fellow eyes, suggesting dysfunction of the ipRGCs. Compared with the responses of the healthy controls, the blue light post-illumination pupil responses were similar in the affected eyes and increased in the fellow non-affected eyes. This suggests a possible...... of this study was to investigate the ipRGC mediated pupil response in patients with a unilateral non-arteritic anterior ischemic optic neuropathy (NAION). Consensual pupil responses during and after exposure to continuous 20 s blue (470 nm) or red (660 nm) light of high intensity (300 cd/m(2)) were recorded...

  20. Dibucaine mitigates spreading depolarization in human neocortical slices and prevents acute dendritic injury in the ischemic rodent neocortex.

    Directory of Open Access Journals (Sweden)

    W Christopher Risher

    Full Text Available Spreading depolarizations that occur in patients with malignant stroke, subarachnoid/intracranial hemorrhage, and traumatic brain injury are known to facilitate neuronal damage in metabolically compromised brain tissue. The dramatic failure of brain ion homeostasis caused by propagating spreading depolarizations results in neuronal and astroglial swelling. In essence, swelling is the initial response and a sign of the acute neuronal injury that follows if energy deprivation is maintained. Choosing spreading depolarizations as a target for therapeutic intervention, we have used human brain slices and in vivo real-time two-photon laser scanning microscopy in the mouse neocortex to study potentially useful therapeutics against spreading depolarization-induced injury.We have shown that anoxic or terminal depolarization, a spreading depolarization wave ignited in the ischemic core where neurons cannot repolarize, can be evoked in human slices from pediatric brains during simulated ischemia induced by oxygen/glucose deprivation or by exposure to ouabain. Changes in light transmittance (LT tracked terminal depolarization in time and space. Though spreading depolarizations are notoriously difficult to block, terminal depolarization onset was delayed by dibucaine, a local amide anesthetic and sodium channel blocker. Remarkably, the occurrence of ouabain-induced terminal depolarization was delayed at a concentration of 1 µM that preserves synaptic function. Moreover, in vivo two-photon imaging in the penumbra revealed that, though spreading depolarizations did still occur, spreading depolarization-induced dendritic injury was inhibited by dibucaine administered intravenously at 2.5 mg/kg in a mouse stroke model.Dibucaine mitigated the effects of spreading depolarization at a concentration that could be well-tolerated therapeutically. Hence, dibucaine is a promising candidate to protect the brain from ischemic injury with an approach that does not rely on

  1. Omega-3 polyunsaturated fatty acids ameliorate neuroinflammation and mitigate ischemic stroke damage through interactions with astrocytes and microglia.

    Science.gov (United States)

    Zendedel, Adib; Habib, Pardes; Dang, Jon; Lammerding, Leoni; Hoffmann, Stefanie; Beyer, Cordian; Slowik, Alexander

    2015-01-15

    Omega-3 polyunsaturated fatty acids (PUFA n3) provide neuroprotection due to their anti-inflammatory and anti-apoptotic properties as well as their regulatory function on growth factors and neuronal plasticity. These qualities enable PUFA n3 to ameliorate stroke outcome and limit neuronal damage. Young adult male rats received transient middle cerebral artery occlusion (tMCAO). PUFA n3 were intravenously administered into the jugular vein immediately after stroke and 12h later. We analyzed stroke volume and behavioral performance as well as the regulation of functionally-relevant genes in the penumbra. The extent of ischemic damage was reduced and behavioral performance improved subject to applied PUFA n3. Expression of Tau and growth-associated protein-43 genes were likewise restored. Ischemia-induced increase of cytokine mRNA levels was abated by PUFA n3. Using an in vitro approach, we demonstrate that cultured astroglial and microglia directly respond to PUFA n3 administration by preventing ischemia-induced increase of cyclooxygenase 2, hypoxia-inducible factor 1alpha, inducible nitric oxide synthase, and interleukin 1beta. Cultured cortical neurons also appeared as direct targets, since PUFA n3 shifted the Bcl-2-like protein 4 (Bax)/B-cell lymphoma 2 (Bcl 2) ratio towards an anti-apoptotic constellation. Thus, PUFA n3 reveal a high neuroprotective and anti-inflammatory potential in an acute ischemic stroke model by targeting astroglial and microglial function as well as improving neuronal survival strategies. Our findings signify the potential clinical feasibility of PUFA n3 therapeutic treatment in stroke and other acute neurological diseases.

  2. Urinary albumin excretion. An independent predictor of ischemic heart disease

    DEFF Research Database (Denmark)

    Borch-Johnsen, K; Feldt-Rasmussen, B; Strandgaard, S

    1999-01-01

    ischemic heart disease (IHD) in a population-based cohort. In 1983, urinary albumin and creatinine levels were measured, along with the conventional atherosclerotic risk factors, in 2085 consecutive participants without IHD, renal disease, urinary tract infection, or diabetes mellitus. The participants......Cross-sectional studies suggest that an increased urinary albumin excretion rate is associated with cardiovascular disease, dyslipidemia, and hypertension. The purpose of this study was to analyze prospectively whether the urinary albumin-to -creatinine (A/C) ratio can independently predict......, 1.3 to 3.9, P=0.002), and the 10-year disease-free survival decreased from 97% to 91% (P

  3. 'Crescendo' transient ischemic attacks: clinical and angiographic correlations.

    Science.gov (United States)

    Rothrock, J F; Lyden, P D; Yee, J; Wiederholt, W C

    1988-02-01

    Forty-seven consecutive patients presenting acutely with repetitive symptoms indicative of anterior circulation ischemia ("crescendo" transient ischemic attacks) were evaluated to identify clinical features that might reliably predict the presence of significant stenosis, ulceration, or both in the presumably symptomatic internal carotid artery. Angiographic or intraoperative correlation was obtained in all patients, and 26 (55%) were found to have anatomically significant disease. Of 20 patients with signs or symptoms suggestive of cortical ischemia, amaurosis fugax, or both, 17 (85%) had "positive" angiograms; of 18 with numbness/weakness only, 9 (50%) had positive angiograms; of 9 whose symptoms suggested lacunar ischemia, none had positive angiograms.

  4. Ischemic heart disease in women

    Directory of Open Access Journals (Sweden)

    Stella Iraklianou

    2009-10-01

    Full Text Available Coronary heart disease has long been recognized as the leading cause of death among middle-aged men and an equally important cause of death and disability among older women. Women with acute ischemic syndromes tend to be older than men with such syndromes. This is considered to be attributed to the protective effects of female ovarian sex hormones. Estrogen express an antiatherogenic profile via mechanisms that cause favorable modifications of lipoprotein levels, coagulation and fibrolytic system and alterations in the wall of vessels that cause vasodilation. Women are susceptible to coronary heart disease because of differences in the anatomy and physiology of their vessels. Women's coronary arteries are smaller and have more diffuse disease than men's. Ischemia can be induced in women without flow limiting stenosis because of endothelial dysfunction or coronary spasm. Usually, the way of manifestation of the disease and ECG abnormalities are not typical in women. Female patients usually delay to seek treatment for their symptoms .The way of evaluation and treatment is usually conservative in women than male counterparts. The diagnosis of the disease is overestimated in men and the treatment is more often invasive, even in the category of low risk. Reversely, women of high risk are less likely to undergo a full assessment and invasive diagnostic and therapeutic interventions are seldom. Recommendations of the American Heart Association for ischemic heart disease in women are in accordance to alterations in the way of life interventions in major risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, preventive use of medications and drugs that are not recommended. In this category of medications belong hormone replacement therapy (HRT.The last is not recommended for primary and secondary prevention of coronary heart disease in women.

  5. Quantitative Measurement of Physical Activity in Acute Ischemic Stroke and Transient Ischemic Attack

    DEFF Research Database (Denmark)

    Strømmen, Anna Maria; Christensen, Thomas; Jensen, Kai

    2014-01-01

    BACKGROUND AND PURPOSE: The purpose of this study was to quantitatively measure and describe the amount and pattern of physical activity in patients within the first week after acute ischemic stroke and transient ischemic attack using accelerometers. METHODS: A total of 100 patients with acute is...... ischemic stroke. The method offers a low cost and noninvasive tool for future clinical interventional physiotherapeutic and early mobilization studies. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01560520....

  6. Correlation between antiplatelet resistance and recurrent cardiac ischemic events of patients with acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    李蕾

    2012-01-01

    Objective To evaluate the predictive value of anti-platelet resistance assessed by whole blood electronic impedance aggregometry(EIA) for the risk of recurrent cardiac ischemic events in patients with acute myocardial infarction(AMI) who underwent coronary stenting. Methods We enrolled

  7. Development and validation of intracranial thrombus segmentation on CT angiography in patients with acute ischemic stroke

    NARCIS (Netherlands)

    E.M.M. Santos (Emilie M.); H. Marquering (Henk); O.A. Berkhemer (Olvert); W.H. van Zwam (Wim); A. van der Lugt (Aad); C.B. Majoie (Charles); W.J. Niessen (Wiro)

    2014-01-01

    textabstractBackground and Purpose: Thrombus characterization is increasingly considered important in predicting treatment success for patients with acute ischemic stroke. The lack of intensity contrast between thrombus and surrounding tissue in CT images makes manual delineation a difficult and tim

  8. Significance of large vessel intracranial occlusion causing acute ischemic stroke and TIA.

    Science.gov (United States)

    Smith, Wade S; Lev, Michael H; English, Joey D; Camargo, Erica C; Chou, Maggie; Johnston, S Claiborne; Gonzalez, Gilberto; Schaefer, Pamela W; Dillon, William P; Koroshetz, Walter J; Furie, Karen L

    2009-12-01

    Acute ischemic stroke due to large vessel occlusion (LVO)-vertebral, basilar, carotid terminus, middle and anterior cerebral arteries-likely portends a worse prognosis than stroke unassociated with LVO. Because little prospective angiographic data have been reported on a cohort of unselected patients with stroke and with transient ischemic attack, the clinical impact of LVO has been difficult to quantify. The Screening Technology and Outcome Project in Stroke Study is a prospective imaging-based study of stroke outcomes performed at 2 academic medical centers. Patients with suspected acute stroke who presented within 24 hours of symptom onset and who underwent multimodality CT/CT angiography were approached for consent for collection of clinical data and 6-month assessment of outcome. Demographic and clinical variables and 6-month modified Rankin Scale scores were collected and combined with blinded interpretation of the CT angiography data. The OR of each variable, including occlusion of intracranial vascular segment in predicting good outcome and 6-month mortality, was calculated using univariate and multivariate logistic regression. Over a 33-month period, 735 patients with suspected stroke were enrolled. Of these, 578 were adjudicated as stroke and 97 as transient ischemic attack. Among patients with stroke, 267 (46%) had LVO accounting for the stroke and 13 (13%) of patients with transient ischemic attack had LVO accounting for transient ischemic attack symptoms. LVO predicted 6-month mortality (OR, 4.5; 95% CI, 2.7 to 7.3; PStroke Scale and age, independently predicted outcome. Large vessel intracranial occlusion accounted for nearly half of acute ischemic strokes in unselected patients presenting to academic medical centers. In addition to age and baseline stroke severity, occlusion of either the basilar or internal carotid terminus segment is an independent predictor of outcome at 6 months.

  9. The Relationship to Cytoskeleton and Apoptosis in Ischemic Penumbra of Human Infarcted Brains%人脑梗死后半暗带区细胞骨架与细胞凋亡的相关性研究

    Institute of Scientific and Technical Information of China (English)

    戚基萍; 王德生; 段淑荣; 赵晶; 马广玉

    2002-01-01

    目的探讨人脑梗死后半暗带区细胞骨架与细胞凋亡的相关性.方法应用10例脑梗死后的尸检脑标本,常规HE染色和免疫组织化学染色检测微管相关蛋白(MAP 2)、胶质纤维酸性蛋白(GFAP)、凋亡相关蛋白(Bcl-2),进行定性和定量分析.结果脑梗死后以梗死灶为中心,按照组织损伤程度由内到外分为4个区(0~3区),其中2区为半暗带区;MAP-2在0区表达消失,1区和2区表达明显增强,3区表达正常;GFAP在0区和1区表达很少,2区和3区随缺血时间延长表达迅速持续升高;Bcl-2在0区和1区表达很少,2区和3区表达显著.结论人脑梗死后涉及细胞骨架改变和细胞凋亡的发生,两者呈正相关.对此过程中涉及到的因素进行干预,可能改变脑卒中的进程和预后.

  10. 25-Hydroxyvitamin D and symptomatic ischemic stroke

    DEFF Research Database (Denmark)

    Brøndum-Jacobsen, Peter; Nordestgaard, Børge G; Schnohr, Peter

    2013-01-01

    OBJECTIVE: We tested the hypothesis that low plasma concentrations of 25-hydroxyvitamin D are associated with increased risk of symptomatic ischemic stroke in the general population. METHODS: We measured plasma 25-hydroxyvitamin D in 10,170 individuals from the general population, the Copenhagen...... City Heart Study. During 21 years of follow-up, 1,256 and 164 persons developed ischemic and hemorrhagic stroke, respectively. In a meta-analysis of ischemic stroke, we included 10 studies, 58,384 participants, and 2,644 events. RESULTS: Stepwise decreasing plasma 25-hydroxyvitamin D concentrations...... were associated with stepwise increasing risk of ischemic stroke both as a function of seasonally adjusted percentile categories and as a function of clinical categories of 25-hydroxyvitamin D (p for trend ≤ 2 × 10(-3) ). In a Cox regression model comparing individuals with plasma 25-hydroxyvitamin D...

  11. ischemic brain injury in neonatal rats

    African Journals Online (AJOL)

    Keywords: Hypoxic–ischemic brain injury, α-Lipoic acid, Cerebral infarct area, Edema, Antioxidants,. Inflammatory markers .... were then moved back to their respective dams and immediately ..... various pro-inflammatory cytokines is stimulated.

  12. Neural Stem Cells and Ischemic Brain

    OpenAIRE

    Zhang, ZhengGang; Chopp, Michael

    2016-01-01

    Stroke activates neural stem cells in the ventricular-subventricular zone (V/SVZ) of the lateral ventricle, which increases neuroblasts and oligodendrocyte progenitor cells (OPCs). Within the ischemic brain, neural stem cells, neuroblasts and OPCs appear to actively communicate with cerebral endothelial cells and other brain parenchymal cells to mediate ischemic brain repair; however, stroke-induced neurogenesis unlikely plays any significant roles in neuronal replacement. In this mini-review...

  13. BOAS与ASTRAL评分预测急性缺血性脑卒中患者3月不良预后的价值%BOAS vs ASTRAL Score in Predicting the 3-month Unfavorable Outcome of Acute Ischemic Stroke

    Institute of Scientific and Technical Information of China (English)

    龙胤希

    2015-01-01

    Objective To study the clinical values of the Bologna Outcome Algorithm for Stroke (BOAS) and the Acute Stroke Registry and Analysis of Lausanne (ASTRAL)Score in evaluating 3-month unfavorable outcome after Acute Ischemic Stroke (AIS). Methods The clinical data and of 305 consecutive patients with AIS admit ed from January 2013 to April 2014 were col ected in this research. Al patients were evaluated according to BOAS Score and ASTRAL Score criteria. Areas under the curve were calculated to quantify the prognostic value and compared with the values between BOAS and ASTRAL Score in predicting. Unfavorable outcome was assessed as a modified Rankin Scale score >2 at 3 months. Calibration was assessed by comparing predicted and observed probability of unfavorable outcome using Pearson correlation coef icient.Results Al patients appeared functional disability (modified Rankin score> 2) or the death of a poor prognosis 115 cases (37.7%) within 3 months.The AUC of BOAS and ASTRAL Score for 3 months were 0.859( =0.000,95%CI:0.804-0.914)and 0.812( =0.000,95%CI:0.750~0.875)respectively.Conclusion BOAS and ASTRAL score assessment of acute ischemic stroke patients with poor prognosis three months have bet er predictive value, is conducive to clinical decision making.%目的比较博洛尼亚卒中结局算法(BOAS)与洛桑卒中评分(ASTRAL)评估急性缺血性脑卒中(AIS)患者3个月不良预后的预测价值。方法收集2013年1月~2014年4月我院305例急性缺血性脑卒中患者的临床资料,比较BOAS与ASTRAL评分预测缺血性脑卒中的3个月的不良预后,并绘制受试工作者特征曲线下面积(AUC),以卒中后3个月的死亡率或功能残障(改良Rankin评分>2分为不良预后),应用Pearson相关分析评估实际与预期结局事件的关联程度。结果全组患者3个月出现功能残障(改良Rankin评分>2)或死亡的不良预后有115例(37.7%);BOAS和ASTRAL评分预测3个

  14. The Ischemic Stroke Genetics Study (ISGS Protocol

    Directory of Open Access Journals (Sweden)

    Rich Stephen S

    2003-07-01

    Full Text Available Abstract Background The molecular basis for the genetic risk of ischemic stroke is likely to be multigenic and influenced by environmental factors. Several small case-control studies have suggested associations between ischemic stroke and polymorphisms of genes that code for coagulation cascade proteins and platelet receptors. Our aim is to investigate potential associations between hemostatic gene polymorphisms and ischemic stroke, with particular emphasis on detailed characterization of the phenotype. Methods/Design The Ischemic Stroke Genetic Study is a prospective, multicenter genetic association study in adults with recent first-ever ischemic stroke confirmed with computed tomography or magnetic resonance imaging. Patients are evaluated at academic medical centers in the United States and compared with sex- and age-matched controls. Stroke subtypes are determined by central blinded adjudication using standardized, validated mechanistic and syndromic classification systems. The panel of genes to be tested for polymorphisms includes β-fibrinogen and platelet glycoprotein Ia, Iba, and IIb/IIIa. Immortalized cell lines are created to allow for time- and cost-efficient testing of additional candidate genes in the future. Discussion The study is designed to minimize survival bias and to allow for exploring associations between specific polymorphisms and individual subtypes of ischemic stroke. The data set will also permit the study of genetic determinants of stroke outcome. Having cell lines will permit testing of future candidate risk factor genes.

  15. [Ocular ischemic syndrome--a case report].

    Science.gov (United States)

    Zemba, M; Avram, Corina Ioana; Ochinciuc, Uliana; Stamate, Alina Cristina; Camburu, Raluca Lăcrămioara

    2013-01-01

    Ocular ischemic syndrome, also known as hypoperfusion/ hypotensive retinopathy or as ischemic oculopathy is a rare ocular disease determined by chronic arterial hypoperfusion through central retinal artery, posterior and anterior ciliary arteries. It is bilateral in 20% of the cases. Most often it appears due to severe occlusion of the carotid arteries (ICA, MCA>ECA), described in 1963 by Kearns and Hollenhorst. Occasionally it can be determined by the obstruction of ophtalmic artery or some arterities (Takayasu, giant cell arteritis). The risk factors are: age between 50-80 years, males (M:F = 2:1), arterial hypertension, diabetes, coronary diseases (5% of the cases develop ocular ischemic syndrome), vascular stroke, hemodialysis. The case we present is of an 63 years old man known with primary arterial hypertension, hypercholesterolemia, diabetes type 2 non insulin dependent and diagnosticated with ischemic cerebral stroke and bilateral obstruction of internal carotid arteries in march 2010, who is presenting for visual impairment in both eyes. The imaging investigations show important carotid occlusion and at the ophthalmologic evaluation there are ocular hypertension and rubeosis iridis at the right eye, optic atrophy at both eyes (complete in the right eye and partial in the left eye), with superior altitudinal visual field defect in left eye. The following diagnosis was established: Chronic ocular ischemic syndrome in both eyes with Neovascular glaucoma at the right eye, Anterior ischemic optic neuropathy at the left eye and laser panphotocoagulation at the right eye was started.

  16. Thrombolytic therapy for acute ischemic stroke after recent transient ischemic attack.

    Science.gov (United States)

    Alonso de Leciñana, María; Fuentes, Blanca; Masjuan, Jaime; Simal, Patricia; Díaz-Otero, Fernando; Reig, Gemma; Díez-Tejedor, Exuperio; Gil-Nuñez, Antonio; Vivancos, Jose; Egido, Jose-Antonio

    2012-04-01

    Safety and efficacy of intravenous thrombolysis in stroke patients with recent transient ischemic attack are hotly debated. Patients suffering transient ischemic attack may present with diffusion-weighted imaging lesions, and although normal computed tomography would not preclude thrombolysis, the concern is that they may be at higher risk for hemorrhage post-thrombolysis treatment. Prior ipsilateral transient ischemic attack might provide protection due to ischemic preconditioning. We assessed post-thrombolysis outcomes in stroke patients who had prior transient ischemic attack. Multicentered prospective study of consecutive acute stroke patients treated with intravenous tissue plasminogen activator (tPA). Ipsilateral transient ischemic attack, baseline characteristics, risk factors, etiology, and time-lapse to treatment were recorded. National Institutes of Health Stroke Scale at seven-days and modified Rankin Scale at three-months, symptomatic intracranial hemorrhage, and mortality were compared in patients with and without transient ischemic attack. There were 877 patients included, 60 (6·84%) had previous ipsilateral transient ischemic attack within one-month prior to the current stroke (65% in the previous 24 h). Transient ischemic attack patients were more frequently men (70% vs. 53%; P = 0·011), younger (63 vs. 71 years of age; P = 0·011), smokers (37% vs. 25%; P = 0·043), and with large vessel disease (40% vs. 25%; P = 0·011). Severity of stroke at onset was similar to those with and without prior transient ischemic attack (median National Institutes of Health Stroke Scale score 12 vs. 14 P = 0·134). Those with previous transient ischemic attack were treated earlier (117 ± 52 vs. 144 ± 38 mins; P ischemic attack was not associated with differences in stroke outcome such as independence (modified Rankin Scale 0-2) (odds ratios: 1·035 (0·57-1·93) P = 0·91), mortality (odds ratios: 0·99 (0·37-2·67) P = 0

  17. The clot burden score, the Boston Acute Stroke Imaging Scale, the cerebral blood volume ASPECTS, and two novel imaging parameters in the prediction of clinical outcome of ischemic stroke patients receiving intravenous thrombolytic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sillanpaa, Niko; Hakomaki, Jari; Lahteela, Arto; Dastidar, Prasun; Soimakallio, Seppo [Tampere University Hospital, Medical Imaging Center, Tampere (Finland); Saarinen, Jukka T.; Numminen, Heikki; Elovaara, Irina [Tampere University Hospital, Department of Neurology, Tampere (Finland); Rusanen, Harri [Oulu University Hospital, Department of Neurology, Oulu (Finland)

    2012-07-15

    Recently two classification methods based on the location and the extent of thrombosis detected with CT angiography have been introduced: the Boston Acute Stroke Imaging Scale (BASIS) and the clot burden score (CBS). We studied the performance of BASIS and CBS in predicting good clinical outcome (mRS {<=}2 at 90 days) in an acute (<3 h) stroke cohort treated with intravenous thrombolytic therapy. Eighty-three consecutive patients who underwent multimodal CT were analyzed. Binary logistic regression model was used to assess how BASIS, CBS, and cerebral blood volume (CBV) ASPECTS predict favorable clinical outcome. Diagnostic sensitivities and specificities were calculated and compared. Patients with low CBS and CBV ASPECTS scores and major strokes according to BASIS had significantly higher admission NIHSS scores, larger perfusion defects, and more often poor clinical outcome. In logistic regression analysis, CBV ASPECTS, CBS and BASIS were significantly associated with the clinical outcome. The performance of BASIS improved when patients with thrombosis of the M2 segment of the middle cerebral artery were classified as having minor stroke (M1-BASIS). In the anterior circulation, the sum of CBS and CBV ASPECTS (CBSV) proved to be the most robust predictor of favorable outcome. CBV ASPECTS and CBS had high sensitivity but moderate to poor specificity while BASIS was only moderately sensitive and specific. CBS, BASIS, and CBV ASPECTS are statistically robust and sensitive but unspecific predictors of good clinical outcome. Two new derived imaging parameters, CBSV and M1-BASIS, share these properties and may have increased prognostic value. (orig.)

  18. The Role of Vascular Imaging in the Initial Assessment of Patients with Acute Ischemic Stroke.

    Science.gov (United States)

    Qazi, Emmad; Al-Ajlan, Fahad S; Najm, Mohamed; Menon, Bijoy K

    2016-04-01

    Over the last few years, improvement in radiological imaging and treatment has changed the management of acute ischemic stroke. We have made significant advances in not only the imaging modalities themselves but also in identifying imaging parameters that can help us predict patient outcomes with both intravascular thrombolysis and endovascular thrombectomy. In this review, we describe the added utility of baseline vascular imaging including computed tomography angiography and magnetic resonance angiography in the diagnosis and management of patients with acute ischemic stroke. We focus on information these imaging modalities provide on clot characteristics, tissue state, collateral status, and endovascular planning. We also highlight the benefits of newer imaging modalities like dynamic computed tomography angiography (CTA) and multi-phase CTA. Lastly, we also describe some of the disadvantages of vascular imaging in ischemic stroke.

  19. Toward fully automated processing of dynamic susceptibility contrast perfusion MRI for acute ischemic cerebral stroke.

    Science.gov (United States)

    Kim, Jinsuh; Leira, Enrique C; Callison, Richard C; Ludwig, Bryan; Moritani, Toshio; Magnotta, Vincent A; Madsen, Mark T

    2010-05-01

    quality assessment by two observers revealed that the MTT maps exhibited superior quality over the TTP maps (88% good rating of MTT as compared to 68% of TTP). Our software allowed fully automated deconvolution analysis of DSC PWI using proven efficient algorithms that can be applied to acute stroke treatment decisions. Our streamlined method also offers promise for further development of automated quantitative analysis of the ischemic penumbra.

  20. DIDS prevents ischemic membrane degradation in cultured hippocampal neurons by inhibiting matrix metalloproteinase release.

    Science.gov (United States)

    Pamenter, Matthew E; Ryu, Julie; Hua, Serena T; Perkins, Guy A; Mendiola, Vincent L; Gu, Xiang Q; Ellisman, Mark H; Haddad, Gabriel G

    2012-01-01

    During stroke, cells in the infarct core exhibit rapid failure of their permeability barriers, which releases ions and inflammatory molecules that are deleterious to nearby tissue (the penumbra). Plasma membrane degradation is key to penumbral spread and is mediated by matrix metalloproteinases (MMPs), which are released via vesicular exocytosis into the extracellular fluid in response to stress. DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid) preserves membrane integrity in neurons challenged with an in vitro ischemic penumbral mimic (ischemic solution: IS) and we asked whether this action was mediated via inhibition of MMP activity. In cultured murine hippocampal neurons challenged with IS, intracellular proMMP-2 and -9 expression increased 4-10 fold and extracellular latent and active MMP isoform expression increased 2-22 fold. MMP-mediated extracellular gelatinolytic activity increased ∼20-50 fold, causing detachment of 32.1±4.5% of cells from the matrix and extensive plasma membrane degradation (>60% of cells took up vital dyes and >60% of plasma membranes were fragmented or blebbed). DIDS abolished cellular detachment and membrane degradation in neurons and the pathology-induced extracellular expression of latent and active MMPs. DIDS similarly inhibited extracellular MMP expression and cellular detachment induced by the pro-apoptotic agent staurosporine or the general proteinase agonist 4-aminophenylmercuric acetate (APMA). Conversely, DIDS-treatment did not impair stress-induced intracellular proMMP production, nor the intracellular cleavage of proMMP-2 to the active form, suggesting DIDS interferes with the vesicular extrusion of MMPs rather than directly inhibiting proteinase expression or activation. In support of this hypothesis, an antagonist of the V-type vesicular ATPase also inhibited extracellular MMP expression to a similar degree as DIDS. In addition, in a proteinase-independent model of vesicular exocytosis, DIDS prevented stimulus

  1. DIDS prevents ischemic membrane degradation in cultured hippocampal neurons by inhibiting matrix metalloproteinase release.

    Directory of Open Access Journals (Sweden)

    Matthew E Pamenter

    Full Text Available During stroke, cells in the infarct core exhibit rapid failure of their permeability barriers, which releases ions and inflammatory molecules that are deleterious to nearby tissue (the penumbra. Plasma membrane degradation is key to penumbral spread and is mediated by matrix metalloproteinases (MMPs, which are released via vesicular exocytosis into the extracellular fluid in response to stress. DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid preserves membrane integrity in neurons challenged with an in vitro ischemic penumbral mimic (ischemic solution: IS and we asked whether this action was mediated via inhibition of MMP activity. In cultured murine hippocampal neurons challenged with IS, intracellular proMMP-2 and -9 expression increased 4-10 fold and extracellular latent and active MMP isoform expression increased 2-22 fold. MMP-mediated extracellular gelatinolytic activity increased ∼20-50 fold, causing detachment of 32.1±4.5% of cells from the matrix and extensive plasma membrane degradation (>60% of cells took up vital dyes and >60% of plasma membranes were fragmented or blebbed. DIDS abolished cellular detachment and membrane degradation in neurons and the pathology-induced extracellular expression of latent and active MMPs. DIDS similarly inhibited extracellular MMP expression and cellular detachment induced by the pro-apoptotic agent staurosporine or the general proteinase agonist 4-aminophenylmercuric acetate (APMA. Conversely, DIDS-treatment did not impair stress-induced intracellular proMMP production, nor the intracellular cleavage of proMMP-2 to the active form, suggesting DIDS interferes with the vesicular extrusion of MMPs rather than directly inhibiting proteinase expression or activation. In support of this hypothesis, an antagonist of the V-type vesicular ATPase also inhibited extracellular MMP expression to a similar degree as DIDS. In addition, in a proteinase-independent model of vesicular exocytosis, DIDS

  2. Genetically elevated C-reactive protein and ischemic vascular disease

    DEFF Research Database (Denmark)

    Zacho, J.; Tybjaerg-Hansen, A.; Jensen, J.S.

    2008-01-01

    Background: Elevated levels of C-reactive protein (CRP) are associated with increased risks of ischemic heart disease and ischemic cerebrovascular disease. We tested whether this is a causal association. Methods: We studied 10,276 persons from a general population cohort, including 1786 in whom...... ischemic heart disease developed and 741 in whom ischemic cerebrovascular disease developed. We examined another 31,992 persons from a cross-sectional general population study, of whom 2521 had ischemic heart disease and 1483 had ischemic cerebrovascular disease. Finally, we compared 2238 patients...... with ischemic heart disease with 4474 control subjects and 612 patients with ischemic cerebrovascular disease with 1224 control subjects. We measured levels of high-sensitivity CRP and conducted genotyping for four CRP polymorphisms and two apolipoprotein E polymorphisms. Results: The risk of ischemic heart...

  3. Occurrence and predictors of persistent impaired glucose tolerance after acute ischemic stroke or transient ischemic attack

    NARCIS (Netherlands)

    S. Fonville (Susanne); H.M. den Hertog (Heleen); A.A.M. Zandbergen (Adrienne); P.J. Koudstaal (Peter Jan); H.F. Lingsma (Hester)

    2014-01-01

    textabstractBackground Impaired glucose tolerance is often present in patients with a transient ischemic attack (TIA) or ischemic stroke and doubles the risk of recurrent stroke. This impaired glucose tolerance can be transient, reflecting an acute stress response, or persistent, representing undiag

  4. The ischemic preconditioning effect of adenosine in patients with ischemic heart disease

    Directory of Open Access Journals (Sweden)

    Berglund Margareta

    2009-11-01

    Full Text Available Abstract Introduction In vivo and in vitro evidence suggests that adenosine and its agonists play key roles in the process of ischemic preconditioning. The effects of low-dose adenosine infusion on ischemic preconditioning have not been thoroughly studied in humans. Aims We hypothesised that a low-dose adenosine infusion could reduce the ischemic burden evoked by physical exercise and improve the regional left ventricular (LV systolic function. Materials and methods We studied nine severely symptomatic male patients with severe coronary artery disease. Myocardial ischemia was induced by exercise on two separate occasions and quantified by Tissue Doppler Echocardiography. Prior to the exercise test, intravenous low-dose adenosine or placebo was infused over ten minutes according to a randomized, double blind, cross-over protocol. The LV walls were defined as ischemic if a reduction, no increment, or an increment of Results PSV increased from baseline to maximal exercise in non-ischemic walls both during placebo (P = 0.0001 and low-dose adenosine infusion (P = 0.0009. However, in the ischemic walls, PSV increased only during low-dose adenosine infusion (P = 0.001, while no changes in PSV occurred during placebo infusion (P = NS. Conclusion Low-dose adenosine infusion reduced the ischemic burden and improved LV regional systolic function in the ischemic walls of patients with exercise-induced myocardial ischemia, confirming that adenosine is a potential preconditioning agent in humans.

  5. Study of retinal vessel oxygen saturation in ischemic and non-ischemic branch retinal vein occlusion

    Directory of Open Access Journals (Sweden)

    Lei-Lei Lin

    2016-01-01

    Full Text Available AIM: To explore how oxygen saturation in retinal blood vessels is altered in ischemic and non-ischemic branch retinal vein occlusion (BRVO. METHODS: Fifty BRVO eyes were divided into ischemic (n=26 and non-ischemic (n=24 groups, based on fundus fluorescein angiography. Healthy individuals (n=52 and n=48, respectively were also recruited as controls for the two groups. The mean oxygen saturations of the occluded vessels and central vessels were measured by oximetry in the BRVO and control groups. RESULTS: In the ischemic BRVO group, the occluded arterioles oxygen saturation (SaO2-A, 106.0%±14.3%, instead of the occluded venule oxygen saturation (SaO2-V, 60.8%±9.4%, showed increases when compared with those in the same quadrant vessels (SaO2-A, 86.1%±16.5% in the contralateral eyes (P<0.05. The oxygen saturations of the central vessels showed similar trends with those of the occluded vessels. In the non-ischemic BRVO group, the occluded and central SaO2-V and SaO2-A showed no significant changes. In both the ischemic and non-ischemic BRVOs, the central SaO2-A was significantly increased when compared to healthy individuals. CONCLUSION: Obvious changes in the occluded and central SaO2-A were found in the ischemic BRVO group, indicating that disorders of oxygen metabolism in the arterioles may participate in the pathogenesis of ischemic BRVO.

  6. [Intravenous administration of a tissue plasminogen activator beyond 3 hours of the onset of acute ischemic stroke--MRI-based decision making].

    Science.gov (United States)

    Kakuda, Wataru; Abo, Masahiro

    2008-10-01

    After large CT-based clinical trials have failed to prove the benefits of intravenous tissue plasminogen activator (tPA) administration for ischemic stroke patients beyond 3 hours of the onset of the concept of PWI/DWI mismatch which is the volume difference between a PWI lesion and DWI lesion on MRI scans, has been proposed to facilitate the selection of patients with a salvageable area. PWI/DWI mismatch is considered to represent the tissue that is not irreversibly injured and can respond to early reperfusion therapy. When an ischemic lesion is divided into 4 regions, namely, ischemic core, reversible DWI lesion, penumbra and benign oligemia, both the reversible DWI lesion and penumbra are considered to be an optimal targets for thrombolysis. In order to clarify the clinical significance of PWI/DWI mismatch in the selection of candidates for tPA therapy, some multicenter trials were performed. The results of DIAS (desmoteplase in acute ischemic stroke)/DEDAS (dose escalation of desmoteplase for acute ischemic stroke)/DIAS-2 did not difinitly demonstrate the clinical benefits of desmoteplase administration in patients with PWI/DWI mismatch between 3 to 9 hours of onset; in fact, DIAS-2 could not prove any effect of the drug. DEFUSE (diffusion and perfusion imaging evaluation for understanding stroke evolution), in which tPA was administered to all participants between 3 to 6 hours of stroke onset, showed that the occurrence of early reperfusion led to a favorable clinical response in patients with PWI/DWI mismatch. In contrast, early reperfusion was not beneficial in patients without PWI/DWI mismatch. In EPITHET (echoplanar imaging thrombolysis evaluation trial), stroke patients who showed PWI/DWI mismatch after 3 to 6 hours of the onset were assigned to receive either alteplase or placebo administration: lesion growth was lesser in patients with alteplase than in those who received placebo, although the difference was not statistically significant because of a

  7. Fatigue, General Health, and Ischemic Heart Disease in Older Adults

    DEFF Research Database (Denmark)

    Ekmann, Anette; Petersen, Inge; Mänty, Minna Regina

    2013-01-01

    Backgrounds.Fatigue has been shown to predict ischemic heart disease (IHD) and mortality in nonsmoking middle-aged men free of cardiovascular disease. The aim of this study was to investigate the predictive value of fatigue for IHD and general health in nondisabled individuals free...... of cardiovascular disease and older than 70 years. METHODS: The study population was drawn from The Longitudinal Study of Aging Danish Twins. In total, 1,696 participants were followed up for 2-10 years by questionnaires and 10-16 years through registries. Kaplan Meier, Cox Proportional Hazard and logistic......-related diagnoses, no use of heart medication, sustained good mobility, and participation at follow-up. IHD was defined as first hospitalization due to IHD (ICD10: I20-I25) or death due to IHD as primary cause. RESULTS: Participants without fatigue had higher chances of a sustained good general health at 2 (odds...

  8. Fasting and non-fasting triglycerides and risk of ischemic cardiovascular disease in Japanese men and women: the Circulatory Risk in Communities Study (CIRCS).

    Science.gov (United States)

    Iso, Hiroyasu; Imano, Hironori; Yamagishi, Kazumasa; Ohira, Tetsuya; Cui, Renzhe; Noda, Hiroyuki; Sato, Shinichi; Kiyama, Masahiko; Okada, Takeo; Hitsumoto, Shinichi; Tanigawa, Takeshi; Kitamura, Akihiko

    2014-11-01

    Non-fasting triglycerides were reported to have a greater impact on risk of ischemic cardiovascular events than fasting triglycerides. However, evidence from Asia, where the prevalence of dyslipidemia is generally lower, has been limited. We used 1975-1986 baseline surveys to investigate cohort data of 10,659 (4264 men and 6395 women) residents aged 40-69 years, initially free from ischemic heart disease and stroke, in four Japanese communities. Serum triglyceride concentrations at baseline were obtained for 2424 fasting (≥8 h after meal) and 8235 non-fasting (disease and 666 (349 men and 317 women) ischemic stroke. After adjustment for age, sex and known cardiovascular risk factors, multivariable hazard ratios (95%CI) of ischemic cardiovascular disease (ischemic heart disease and ischemic stroke) for the highest versus lowest quartiles of triglycerides were 1.71 (1.14-2.59), P for trend = 0.013, for fasting participants and 1.60 (1.25-2.05), P for trend disease than for ischemic stroke. After further adjustment for HDL-cholesterol, these associations were slightly attenuated, but remained statistically significant. Non-fasting as well as fasting triglycerides are predictive of risk of ischemic cardiovascular disease for Japanese men, as are non-fasting triglycerides for women. Copyright © 2014. Published by Elsevier Ireland Ltd.

  9. Critical care in acute ischemic stroke.

    Science.gov (United States)

    McDermott, M; Jacobs, T; Morgenstern, L

    2017-01-01

    Most ischemic strokes are managed on the ward or on designated stroke units. A significant proportion of patients with ischemic stroke require more specialized care. Several studies have shown improved outcomes for patients with acute ischemic stroke when neurocritical care services are available. Features of acute ischemic stroke patients requiring intensive care unit-level care include airway or respiratory compromise; large cerebral or cerebellar hemisphere infarction with swelling; infarction with symptomatic hemorrhagic transformation; infarction complicated by seizures; and a large proportion of patients require close management of blood pressure after thrombolytics. In this chapter, we discuss aspects of acute ischemic stroke care that are of particular relevance to a neurointensivist, covering neuropathology, neurodiagnostics and imaging, blood pressure management, glycemic control, temperature management, and the selection and timing of antithrombotics. We also focus on the care of patients who have received intravenous thrombolysis or mechanical thrombectomy. Complex clinical decision making in decompressive hemicraniectomy for hemispheric infarction and urgent management of basilar artery thrombosis are specifically addressed. © 2017 Elsevier B.V. All rights reserved.

  10. Inflammatory mechanisms in ischemic stroke: therapeutic approaches

    Directory of Open Access Journals (Sweden)

    Kirchgessner Annette

    2009-11-01

    Full Text Available Abstract Acute ischemic stroke is the third leading cause of death in industrialized countries and the most frequent cause of permanent disability in adults worldwide. Despite advances in the understanding of the pathophysiology of cerebral ischemia, therapeutic options remain limited. Only recombinant tissue-plasminogen activator (rt-PA for thrombolysis is currently approved for use in the treatment of this devastating disease. However, its use is limited by its short therapeutic window (three hours, complications derived essentially from the risk of hemorrhage, and the potential damage from reperfusion/ischemic injury. Two important pathophysiological mechanisms involved during ischemic stroke are oxidative stress and inflammation. Brain tissue is not well equipped with antioxidant defenses, so reactive oxygen species and other free radicals/oxidants, released by inflammatory cells, threaten tissue viability in the vicinity of the ischemic core. This review will discuss the molecular aspects of oxidative stress and inflammation in ischemic stroke and potential therapeutic strategies that target neuroinflammation and the innate immune system. Currently, little is known about endogenous counterregulatory immune mechanisms. However, recent studies showing that regulatory T cells are major cerebroprotective immunomodulators after stroke suggest that targeting the endogenous adaptive immune response may offer novel promising neuroprotectant therapies.

  11. Thrombophilia And Arterial Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    A.A. Abrishamizadeh

    2017-02-01

    Full Text Available Ischemic stroke (IS is a common cause of morbidity and mortality with significant socioeconomic impact especially when it affects young patients. Compared to the older adults, the incidence, risk factors, and etiology are distinctly different in younger IS. Hypercoagulable states are relatively more commonly detected in younger IS patients. Thrombophilic states are disorders of hemostatic mechanisms that result in a predisposition to thrombosis .Thrombophilia is an established cause of venous thrombosis. Therefore, it is tempting to assume that these disorders might have a similar relationship with arterial thrombosis. Despite this fact that 1-4 % of ischemic strokes are attributed to Thrombophillia, this   alone rarely causes arterial occlusions .Even in individuals with a positive thrombophilia screen and arterial thrombosis, the former might not be the primary etiological factor. Thrombophilic   disorders can be broadly divided into inherited or acquired conditions. Inherited thrombophilic states include deficiencies of natural anticoagulants such as protein C, protein S, and antithrombin III (AT III deficiency, polymorphisms causing resistance to activated protein C(Factor V Leiden mutation, and disturbance in the clotting balance (prothrombin gene 20210G/A variant. Of all the inherited  thrombophilic disorders, Factor V Leiden mutation is perhaps the commonest cause. On the contrary, acquired thrombophilic disorders are more common and include conditions such as the antiphospholipid syndrome, associated with lupus anticoagulant and anticardiolipin antibodies. The more useful and practical approach of ordering various diagnostic tests for the uncommon thrombophilic states tests should be determined by a detailed clinical history, physical examination, imaging studies and evaluating whether an underlying hypercoagulable state appears more likely. The laboratory thrombophilia   screening should be comprehensive and avoid missing the

  12. Regulation of ion gradients across myocardial ischemic border zones: a biophysical modelling analysis.

    Directory of Open Access Journals (Sweden)

    Steven Niederer

    Full Text Available The myocardial ischemic border zone is associated with the initiation and sustenance of arrhythmias. The profile of ionic concentrations across the border zone play a significant role in determining cellular electrophysiology and conductivity, yet their spatial-temporal evolution and regulation are not well understood. To investigate the changes in ion concentrations that regulate cellular electrophysiology, a mathematical model of ion movement in the intra and extracellular space in the presence of ionic, potential and material property heterogeneities was developed. The model simulates the spatial and temporal evolution of concentrations of potassium, sodium, chloride, calcium, hydrogen and bicarbonate ions and carbon dioxide across an ischemic border zone. Ischemia was simulated by sodium-potassium pump inhibition, potassium channel activation and respiratory and metabolic acidosis. The model predicted significant disparities in the width of the border zone for each ionic species, with intracellular sodium and extracellular potassium having discordant gradients, facilitating multiple gradients in cellular properties across the border zone. Extracellular potassium was found to have the largest border zone and this was attributed to the voltage dependence of the potassium channels. The model also predicted the efflux of [Formula: see text] from the ischemic region due to electrogenic drift and diffusion within the intra and extracellular space, respectively, which contributed to [Formula: see text] depletion in the ischemic region.

  13. Ischemic heart disease: effectiveness and safety of statin treatment ...

    African Journals Online (AJOL)

    Ischemic heart disease: effectiveness and safety of statin treatment in a malaysian tertiary healthcare facility. ... Tropical Journal of Pharmaceutical Research ... and safety of statins in ischemic heart disease (IHD) patients in a Malaysian tertiary ...

  14. Caffeine prevents protection in two human models of ischemic preconditioning.

    NARCIS (Netherlands)

    Riksen, N.P.; Zhou, Z.; Oyen, W.J.G.; Jaspers, R.A.; Ramakers, B.P.; Brouwer, R.M.H.J.; Boerman, O.C.; Steinmetz, N.; Smits, P.; Rongen, G.A.

    2006-01-01

    OBJECTIVES: We studied whether caffeine impairs protection by ischemic preconditioning (IP) in humans. BACKGROUND: Ischemic preconditioning is critically dependent on adenosine receptor stimulation. We hypothesize that the adenosine receptor antagonist caffeine blocks the protective effect of IP.

  15. Caffeine prevents protection in two human models of ischemic preconditioning.

    NARCIS (Netherlands)

    Riksen, N.P.; Zhou, Z.; Oyen, W.J.G.; Jaspers, R.A.; Ramakers, B.P.; Brouwer, R.M.H.J.; Boerman, O.C.; Steinmetz, N.; Smits, P.; Rongen, G.A.

    2006-01-01

    OBJECTIVES: We studied whether caffeine impairs protection by ischemic preconditioning (IP) in humans. BACKGROUND: Ischemic preconditioning is critically dependent on adenosine receptor stimulation. We hypothesize that the adenosine receptor antagonist caffeine blocks the protective effect of IP. ME

  16. Autonomic dysfunction in acute ischemic stroke : An underexplored therapeutic area?

    NARCIS (Netherlands)

    De Raedt, Sylvie; De Vos, Aurelie; De Keyser, Jacques

    2015-01-01

    Impaired autonomic function, characterized by a predominance of sympathetic activity, is common in patients with acute ischemic stroke. This review describes methods to measure autonomic dysfunction in stroke patients. It summarizes a potential relationship between ischemic stroke-associated

  17. Dual antiplatelet therapy after noncardioembolic ischemic stroke or transient ischemic attack: pros and cons.

    Science.gov (United States)

    Hong, Keun-Sik

    2014-07-01

    Dual antiplatelet therapy simultaneously blocks different platelet activation pathways and might thus be more potent at inhibiting platelet activation and more effective at reducing major ischemic vascular events compared to antiplatelet monotherapy. Aspirin plus clopidogrel dual therapy is now the standard therapy for patients with acute coronary syndrome and for those undergoing percutaneous coronary intervention. However, dual antiplatelet therapy carries an increased risk of bleeding. Patients with ischemic stroke or transient ischemic attack (TIA) are generally older and likely to have a fragile cerebrovascular bed, which further increases the risk of systemic major bleeding events and intracranial hemorrhage. Clinical trials and meta-analyses suggest that in comparison to antiplatelet monotherapy, dual antiplatelet therapy initiated early after noncardioembolic ischemic stroke or TIA further reduces the rate of recurrent stroke and major vascular events without significantly increasing the rate of major bleeding events. In contrast, studies of long-term therapy in patients with noncardioembolic ischemic stroke or TIA have yielded inconsistent data regarding the benefit of dual antiplatelet therapy over monotherapy. However, the harm associated with major bleeding events, including intracranial hemorrhage, which is generally more disabling and more fatal than ischemic stroke, is likely to increase with dual antiplatelet therapy. Physicians should carefully assess the benefits and risks of dual antiplatelet therapy versus antiplatelet monotherapy when managing patients with ischemic stroke or TIA.

  18. Resilience in Patients with Ischemic Heart Disease

    Science.gov (United States)

    de Lemos, Conceição Maria Martins; Moraes, David William; Pellanda, Lucia Campos

    2016-01-01

    Background Resilience is a psychosocial factor associated with clinical outcomes in chronic diseases. The relationship between this protective factor and certain diseases, such heart diseases, is still under-explored. Objective The present study sought to investigate the frequency of resilience in individuals with ischemic heart disease. Method This was a cross-sectional study with 133 patients of both genders, aged between 35 and 65 years, treated at Rio Grande do Sul Cardiology Institute - Cardiology University Foundation, with a diagnosis of ischemic heart disease during the study period. Sixty-seven patients had a history of acute myocardial infarction. The individuals were interviewed and evaluated by the Wagnild & Young resilience scale and a sociodemographic questionnaire. Results Eighty-one percent of patients were classified as resilient according to the scale. Conclusion In the sample studied, resilience was identified in high proportion among patients with ischemic heart disease. PMID:26815312

  19. Short Telomere Length and Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Scheller Madrid, Alexander; Rode, Line; Nordestgaard, Børge Grønne

    2016-01-01

    BACKGROUND: Short telomeres are associated with aging and have been associated with a high risk of ischemic heart disease in observational studies; however, the latter association could be due to residual confounding and/or reverse causation. We wanted to test the hypothesis that short telomeres...... are associated with high risk of ischemic heart disease using a Mendelian randomization approach free of reverse causation and of most confounding. METHODS: We genotyped 3 genetic variants in OBFC1 (oligonucleotide/oligosaccharide binding fold containing 1), TERT (telomerase reverse transcriptase), and TERC...... logistic and instrumental variable analysis for genetic estimates. RESULTS: Observationally, a 200-bp-shorter telomere length was associated with a multivariable adjusted hazard ratio for ischemic heart disease of 1.02 (95% CI, 1.01-1.03). Per allele, telomeres were shorter by 67 bp (73-60). In meta...

  20. Cerebrovascular arteriopathy (arteriosclerosis) and ischemic childhood stroke.

    Science.gov (United States)

    Daniels, S R; Bates, S; Lukin, R R; Benton, C; Third, J; Glueck, C J

    1982-01-01

    The aim of this report is to describe the intracranial cerebrovascular abnormalities and clinical status of 8 children who had familial lipoprotein disorders and evidence of thromboembolic cerebrovascular disease. Six of the 8 children had low levels of plasma high density lipoprotein cholesterol, two had high triglyceride levels, and all came from kindreds characterized by familial lipoprotein abnormalities and premature cardio- and/or cerebrovascular atherosclerosis. Vascular occlusion, irregularities of the arterial lumen, beading, tortuosity, and evidence of collateralization were consistently noted. We speculate that cerebrovascular arteriosclerosis in pediatric ischemic stroke victims who have familial lipoprotein abnormalities may be related to lipoprotein-mediated endothelial damage and thrombosis formation, or to the failure to restore endothelial cells' integrity following damage. The apparent association of lipoproteins and strokes in children and their families merits further exploration, particularly when assessing cerebral angiograms in pediatric ischemic stroke victims. In children with unexplained ischemic cerebrovascular accidents, the diagnostic possibility of occlusive arteriosclerosis with thrombosis must be entertained.

  1. Spectroscopic Monitoring of Kidney Tissue Ischemic Injury

    Energy Technology Data Exchange (ETDEWEB)

    Demos, S G; Fitzgerald, J T; Michalopoulou, A P; Troppmann, C

    2004-03-11

    Noninvasive evaluation of tissue viability of donor kidneys used for transplantation is an issue that current technology is not able to address. In this work, we explore optical spectroscopy for its potential to assess the degree of ischemic damage in kidney tissue. We hypothesized that ischemic damage to kidney tissue will give rise to changes in its optical properties which in turn may be used to asses the degree of tissue injury. The experimental results demonstrate that the autofluorescence intensity of the injured kidney is decreasing as a function of time exposed to ischemic injury. Changes were also observed in the NIR light scattering intensities most probably arising from changes due to injury and death of the tissue.

  2. Cardiac magnetic resonance determinants of functional mitral regurgitation in ischemic and non ischemic left ventricular dysfunction.

    Science.gov (United States)

    Fernández-Golfín, Covadonga; De Agustin, Alberto; Manzano, M Carmen; Bustos, Ana; Sánchez, Tibisay; Pérez de Isla, Leopoldo; Fuentes, Manuel; Macaya, Carlos; Zamorano, José

    2011-04-01

    Functional mitral regurgitation (FMR) is frequent in left ventricular (LV) dilatation/dysfunction. Echocardiographic predictors of FMR are known. However, cardiac magnetic resonance (CMR) predictors of FMR have not been fully addressed. The aim of the study was to evaluate CMR mitral valve (MV) parameters associated with FMR in ischemic and non ischemic LV dysfunction. 80 patients with LV ejection fraction below 45% and/or left ventricular dilatation of ischemic and non ischemic etiology were included. Cine-MR images (steady state free-precession) were acquired in a short-axis and 4 chambers views where MV evaluation was performed. Delayed enhancement was performed as well. Significant FMR was established as more than mild MR according to the echocardiographic report. Mean age was 59 years, males 79%. FMR was detected in 20 patients (25%) Significant differences were noted in LV functional parameters and in most MV parameters according to the presence of significant FMR. However, differences were noted between ischemic and non ischemic groups. In the first, differences in most MV parameters remained significant while in the non ischemic, only systolic and diastolic interpapillary muscle distance (1.60 vs. 2.19 cm, P = 0.001; 2. 51 vs. 3.04, P = 0.008) were predictors of FMR. FMR is associated with a more severe LV dilatation/dysfunction in the overall population. CMR MV parameters are associated with the presence of significant FMR and are different between ischemic and non ischemic patients. CMR evaluation of these patients may help in risk stratification as well as in surgical candidate selection.

  3. Polymorphisms in apolipoprotein B and risk of ischemic stroke

    DEFF Research Database (Denmark)

    Benn, Marianne; Nordestgaard, Børge G; Jensen, Jan Skov

    2007-01-01

    Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown.......Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown....

  4. [Nonfasting triglycerides and risk of ischemic stroke--secondary publication

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Jensen, J.S.

    2009-01-01

    The role of triglycerides in the risk of ischemic stroke remains controversial. We tested the hypothesis that increased levels of nonfasting triglycerides are associated with ischemic stroke in the general population. Men with a nonfasting triglyceride level 5 mmol/l had a multivariable, adjusted...... hazard ratio for ischemic stroke of 2.5 (95% confidence interval: 1.3-4.8) compared with men with a nonfasting triglyceride level triglycerides is associated with risk of ischemic stroke Udgivelsesdato...

  5. Anticoagulant Therapy In Ischemic Stroke Or TIA

    Directory of Open Access Journals (Sweden)

    Kaveh Mehrvar

    2017-02-01

    Full Text Available Stroke is the leading cause of disability and the third leading cause of death  . Anticoagulants   have been used to treat patients with acute ischemic stroke for many years. Despite their widespread use, the usefulness of emergency anticoagulation is a subject of debate. Disagreements exist about the best agent to administer, the route of administration, the use of a bolus dose to start treatment, the level of anticoagulation required, and the duration of treatment. There are 2 types of anticoagulants: Parenteral and oral. Heparin is an anticoagulant that used parenteral. Oral anticoagulants are including Warfarin and new anticoagulants such as Dabigatrn,Rivaroxaban ,Apixaban and other newer drugs. In patients with noncardioembolic  ischemic stroke or TIA antiplatelet agents are treatment of choice and preferred to anticoagulants. In cardioembolic  ischemic stroke or TIA with high risk of reembolization  anticoagulants  are considered as preferred treatment.  Warfarin, apixaban10mg/d ,Rivaroxaban20mg/d, and dabigatran 150 mg/d are all indicated for the prevention of recurrent stroke in patients with nonvalvular AF, whether paroxysmal or permanent.Also anticoagulant therapy is recommended for ischemic stroke or TIA patients in the setting of acute MI, atrial or ventricular thrombosis or dilated and restricted cardiomyopathy. Some valvular heart diseases are other indication for anticoagulant therapy in ischemic stroke or TIA patients. Ischemic  Stroke or TIA in patients with Cerebral vein thrombosis and  known hypercoagulable state specially anti phospholipid antibody syndrome are other indications for anticoagulant treatment.

  6. Polymorphism of the methylenetetrahydrofolate reductase gene association with homocysteine and ischemic stroke in type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Sun Jia-Zhong

    2009-12-01

    Full Text Available Background : Ischemic stroke is a frequent heterogeneous multifactorial disease. A number of genetic mutations and environmental factors have been implicated. A polymorphism in the gene for methylenetetrahydrofolate reductase (MTHFR has been reported to be associated with hyperhomocysteinemia a risk for atherosclerotic vascular diseases. Aim : A cross-sectional study was performed to determine the relationship between the gene polymorphism for MTHFR and ischemic stroke in type 2 diabetes mellitus. Materials and Methods : Of the 215 unrelated patients with type 2 diabetes mellitus recruited, 119 patients had ischemic stroke, Control group included 142 healthy subjects. The genotype of the subjects for the C677T polymorphism of MTHFR was analyzed by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP followed by HinfI digestion. Plasma total homocysteine (Hcy levels were measured using high-performance liquid chromatography (HPLC with fluorescence detection. Results : The genotype distribution did not differ between the control subjects and type 2 diabetic patients (P > 0.05. Plasma homocysteine levels were markedly higher in diabetic patients with TT genotype than those with CC or CT genotype (P > 0.05. Ischemic stroke was more frequently observed in type 2 diabetic patients with the TT genotype than in those with the CT and CC genotype (odds ratio=4.04, 95% CI=1.95-8.34, P=0.0036. Logistic regression analysis revealed that the C677T mutation of MTHFR gene was independently associated with ischemic stroke in type 2 diabetes. Conclusion : MTHFR C677T gene polymorphism associated with a predisposition to hyperhomocysteinemia could constitute a useful predictive marker for ischemic stroke in type 2 diabetic Chinese patients.

  7. A metabolic index of ischemic injury for perfusion-recovery of cadaveric rat livers.

    Directory of Open Access Journals (Sweden)

    Sinem Perk

    Full Text Available With over 110,000 patients waiting for organ transplantation, the current crisis in organ transplantation is based on a lack of donors after brain-death (DBD. A very large alternative pool of donor organs that remain untapped are the donors after cardiac death (DCD, recovered after cardiac activity has ceased and therefore sustained some ischemic injury. Machine perfusion has been proposed as a novel modality of organ preservation and treatment to render such cadaveric organs, and in particular livers, transplantable. Two key issues that remain unaddressed are how to assess whether a DCD liver is damaged beyond repair, and whether machine perfusion has rendered an injured organ sufficiently viable for transplantation. In this work, we present a metabolic analysis of the transient responses of cadaveric rat livers during normothermic machine perfusion (NMP, and develop an index of ischemia that enables evaluation of the organ ischemic injury level. Further, we perform a discriminant analysis to construct a classification algorithm with >0.98 specificity to identify whether a given perfused liver is ischemic or fresh, in effect a precursor for an index of transplantability and a basis for the use of statistical process control measures for automated feedback control of treatment of ischemic injury in DCD livers. The analyses yield an index based on squared prediction error (SPE as log(SPE >1.35 indicating ischemia. The differences between metabolic functions of fresh and ischemic livers during perfusion are outlined and the metabolites that varied significantly for ischemic livers are identified as ornithine, arginine, albumin and tyrosine.

  8. A metabolic index of ischemic injury for perfusion-recovery of cadaveric rat livers.

    Science.gov (United States)

    Perk, Sinem; Izamis, Maria-Louisa; Tolboom, Herman; Uygun, Basak; Berthiaume, Francois; Yarmush, Martin L; Uygun, Korkut

    2011-01-01

    With over 110,000 patients waiting for organ transplantation, the current crisis in organ transplantation is based on a lack of donors after brain-death (DBD). A very large alternative pool of donor organs that remain untapped are the donors after cardiac death (DCD), recovered after cardiac activity has ceased and therefore sustained some ischemic injury. Machine perfusion has been proposed as a novel modality of organ preservation and treatment to render such cadaveric organs, and in particular livers, transplantable. Two key issues that remain unaddressed are how to assess whether a DCD liver is damaged beyond repair, and whether machine perfusion has rendered an injured organ sufficiently viable for transplantation. In this work, we present a metabolic analysis of the transient responses of cadaveric rat livers during normothermic machine perfusion (NMP), and develop an index of ischemia that enables evaluation of the organ ischemic injury level. Further, we perform a discriminant analysis to construct a classification algorithm with >0.98 specificity to identify whether a given perfused liver is ischemic or fresh, in effect a precursor for an index of transplantability and a basis for the use of statistical process control measures for automated feedback control of treatment of ischemic injury in DCD livers. The analyses yield an index based on squared prediction error (SPE) as log(SPE) >1.35 indicating ischemia. The differences between metabolic functions of fresh and ischemic livers during perfusion are outlined and the metabolites that varied significantly for ischemic livers are identified as ornithine, arginine, albumin and tyrosine.

  9. Decreased uric acid levels correlate with poor outcomes in acute ischemic stroke patients, but not in cerebral hemorrhage patients.

    Science.gov (United States)

    Wu, Hongliang; Jia, Qian; Liu, Gaifen; Liu, Liping; Pu, Yuehua; Zhao, Xingquan; Wang, Chunxue; Wang, Yilong; Wang, Yongjun

    2014-03-01

    The relationship between uric acid and stroke prognosis is ambiguous. Some studies have explored this relationship in acute stroke but have different results. In this study, we explored the relationship between uric acid levels and 1-year outcomes and vascular events of acute ischemic stroke patients and cerebral hemorrhage patients. In all, 1452 continued first, acute ischemic stroke patients and 380 continued cerebral hemorrhage patients were admitted to our hospitals. Serum uric acid concentrations were measured in 1351 ischemic stroke patients and 380 cerebral hemorrhage patients at admission. We evaluated the relationship between uric acid levels and outcomes (modified Rankin scale [mRS] > 2, all-cause death, vascular events, stroke recurrent) at 14 days, 90 days, and 1 year after stroke onset. The median uric acid concentration was 303.0 μmol/L in ischemic stroke patients and 269 μmol/L in cerebral hemorrhage patients. In univariate analysis, uric acid levels were not correlated with outcomes in cerebral hemorrhage patients. We used multiple logistic regression analysis to show that lower serum uric acid levels independently predicted poor functional outcomes (mRS >2) at 1 year after ischemic stroke onset (odds ratio [OR] = .335, 95% confidence interval [CI]: .164-.684, P = .003). Also, lower serum uric acid levels were independently correlated with vascular events in the first year in ischemic stroke patients. By multiple cox proportional hazards analysis, we obtained data which reveal that serum uric acid levels were not correlated with all-cause death (OR = .992, 95% CI: .683-1.443, P = .969) in ischemic stroke patients. Serum uric acid may be neuroprotective in acute ischemic stroke patients. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  10. Ischemic Gastropathic Ulcer Mimics Gastric Cancer

    Directory of Open Access Journals (Sweden)

    Saleh Daher

    2016-01-01

    Full Text Available Gastric ulcer due to mesenteric ischemia is a rare clinical finding. As a result, few reports of ischemic gastric ulcers have been reported in the literature. The diagnosis of ischemic gastropathy is seldom considered in patients presenting with abdominal pain and gastric ulcers. In this case report, we describe a patient with increasing abdominal pain, weight loss, and gastric ulcers, who underwent extensive medical evaluation and whose symptoms were resistant to medical interventions. Finally he was diagnosed with chronic mesenteric ischemia, and his clinical and endoscopic abnormalities resolved after surgical revascularization of both the superior mesenteric artery and the celiac trunk.

  11. Anterior ischemic optic neuropathy following dengue fever.

    Science.gov (United States)

    Ramakrishnan, Reshma; Shrivastava, Saurabh; Deshpande, Shrikant; Patkar, Priyanka

    2016-01-01

    Dengue fever is caused by a flavivirus. This infection is endemic in the tropics and warm temperate regions of the world. Ocular manifestations of dengue fever include subconjunctival, vitreous, and retinal haemorrhages; posterior uveitis; optic neuritis; and maculopathies, haemorrhage, and oedema. However anterior ischemic optic neuropathy is a rare presentation. Optic nerve ischemia most frequently occurs at the optic nerve head, where structural crowding of nerve fibers and reduction of the vascular supply may combine to impair perfusion to a critical degree and produce optic disc oedema. Here we present a case of anterior ischemic optic neurapathy associated with dengue fever.

  12. Flow Augmentation in Acute Ischemic Stroke.

    Science.gov (United States)

    Yadollahikhales, Golnaz; Borhani-Haghighi, Afshin; Torabi-Nami, Mohammad; Edgell, Randall; Cruz-Flores, Salvador

    2016-01-01

    There is an urgent need for additional therapeutic options for acute ischemic stroke considering the major pitfalls of the options available. Herein, we briefly review the role of cerebral blood flow, collaterals, vasoreactivity, and reperfusion injury in acute ischemic stroke. Then, we reviewed pharmacological and interventional measures such as volume expansion and induced hypertension, intra-aortic balloon counterpulsation, partial aortic occlusion, extracranial-intracranial carotid bypass surgery, sphenopalatine ganglion stimulation, and transcranial laser therapy with regard to their effects on flow augmentation and neuroprotection. © The Author(s) 2014.

  13. Blood pressure, risk of ischemic cerebrovascular and ischemic heart disease, and longevity in alpha(1)-antitrypsin deficiency

    DEFF Research Database (Denmark)

    Dahl, Morten; Tybjaerg-Hansen, Anne; Sillesen, Henrik

    2003-01-01

    Because elastase in alpha(1)-antitrypsin deficiency may attack elastin in the arterial wall, we tested whether alpha(1)-antitrypsin deficiency is associated with reduced blood pressure, risk of ischemic cerebrovascular (ICVD) and ischemic heart disease (IHD), and longevity.......Because elastase in alpha(1)-antitrypsin deficiency may attack elastin in the arterial wall, we tested whether alpha(1)-antitrypsin deficiency is associated with reduced blood pressure, risk of ischemic cerebrovascular (ICVD) and ischemic heart disease (IHD), and longevity....

  14. Shades and Penumbra of Globalization

    Directory of Open Access Journals (Sweden)

    Mircea PERPELEA

    2015-09-01

    Full Text Available Those who are often identified as challengers of globalization, from the standpoint of defending a defined modernity since the inception of capitalism1, they are, in most cases, only one or all of the contestants of the dominant paradigm of globalization. Almost no one denies that requires empirical reality - that the current world is changing, both in the most developed societies, and as a result their impact on other companies, globally. Change exists and it is not contested. Its interpretations are contested and the practice based on these interpretations that are to be adopted in relation to them. Stating that this practice is itself a component of globalization, one of the factors that shape, may extend or limit his influence and can “tame” those it deems undesirable effects. Therefore, the debate about globalization acquires exceptional importance in relation to reality. Because it has become one of the most important components of this reality, yet we, that is globalization. And because the way in which reality will evolve from now on will depend, in turn, how that will evolve debate about globalization, building intellectual infrastructure, knowledge and value that will underpin future political and economic action. As stated, rightly, Immanuel Wallerstein, just we humans are the ones who, through their ideas, beliefs and actions constitute uncertainty factors of the future.

  15. Penumbra: Doctoral support as drama

    DEFF Research Database (Denmark)

    Wisker, Gina; Robinson, Gill; Bengtsen, Søren Smedegaard

    2017-01-01

    Much international doctoral learning research focuses on personal, institutional and learning support provided by supervisors, managed relationships,‘nudging’ robust, conceptual, critical, creative work. Other work focuses on stresses experienced in supervisor-student relationships and doctoral j...

  16. Long-term impact of diabetes in patients hospitalized with ischemic and non-ischemic heart failure

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Weeke, Peter; Pecini, Redi

    2010-01-01

    Abstract Objectives. Diabetes mellitus (DM) in combination with heart failure (HF) is associated with a high risk of death, but it is uncertain whether the prognosis differs in ischemic and non-ischemic HF groups. Design. One thousand, three hundred and six patients with ischemic HF and 1315...

  17. Troponin elevation in acute ischemic stroke (TRELAS)--protocol of a prospective observational trial.

    Science.gov (United States)

    Scheitz, Jan F; Mochmann, Hans-Christian; Nolte, Christian H; Haeusler, Karl G; Audebert, Heinrich J; Heuschmann, Peter U; Laufs, Ulrich; Witzenbichler, Bernhard; Schultheiss, Heinz-Peter; Endres, Matthias

    2011-08-08

    Levels of the cardiac muscle regulatory protein troponin T (cTnT) are frequently elevated in patients with acute ischemic stroke and elevated cTnT predicts poor outcome and mortality. The pathomechanism of troponin release may relate to co-morbid coronary artery disease and myocardial ischemia or, alternatively, to neurogenic cardiac damage due to autonomic activation after acute ischemic stroke. Therefore, there is uncertainty about how acute ischemic stroke patients with increased cTnT levels should be managed regarding diagnostic and therapeutic workup. The primary objective of the prospective observational trial TRELAS (TRoponin ELevation in Acute ischemic Stroke) is to investigate the frequency and underlying pathomechanism of cTnT elevation in acute ischemic stroke patients in order to give guidance for clinical practice. All consecutive patients with acute ischemic stroke admitted within 72 hours after symptom onset to the Department of Neurology at the Campus Benjamin Franklin of the University Hospital Charité will be screened for cTnT elevations (i.e. ≥ 0.05 μg/l) on admission and again on the following day. Patients with increased cTnT will undergo coronary angiography within 72 hours. Diagnostic findings of coronary angiograms will be compared with age- and gender-matched patients presenting with Non-ST-Elevation myocardial infarction to the Department of Cardiology. The primary endpoint of the study will be the occurrence of culprit lesions in the coronary angiogram indicating underlying co-morbid obstructive coronary artery disease. Secondary endpoints will be the localization of stroke in the cerebral imaging and left ventriculographic findings of wall motion abnormalities suggestive of stroke-induced global cardiac dysfunction. TRELAS will prospectively determine the frequency and possible etiology of troponin elevation in a large cohort of ischemic stroke patients. The findings are expected to contribute to clarify pathophysiologic concepts of

  18. CT imaging in acute ischemic stroke

    NARCIS (Netherlands)

    Borst, J.

    2016-01-01

    Time is of the essence when treating acute ischemic stroke, to limit the damage caused. One form of intra-arterial treatment (IAT) used in such cases is the mechanical removal of the blood clot using stent-retrievers. It is thought that patient selection for IAT requires improvement and that CT

  19. Hyperglycemia Increases Susceptibility to Ischemic Necrosis

    Directory of Open Access Journals (Sweden)

    D. Lévigne

    2013-01-01

    Full Text Available Diabetic patients are at risk for spontaneous foot ulcers, chronic wounds, infections, and tissue necrosis. Current theories suggest that the development and progression of diabetic foot ulcers are mainly caused by arteriosclerosis and peripheral neuropathy. Tissue necrosis plays a primordial role in the progression of diabetic foot ulcers but the underlying mechanisms are poorly understood. The aim of the present study was to investigate the effects of hyperglycemia per se on the susceptibility of ischemic tissue to necrosis, using a critical ischemic hind limb animal model. We inflicted the same degree of ischemia in both euglycemic and streptozotocin-induced hyperglycemic rats by resecting the external iliac, the femoral, and the saphenous arteries. Postoperative laser Doppler flowmetry of the ischemic feet showed the same degree of reduction in skin perfusion in both hyperglycemic and euglycemic animals. Nevertheless, we found a significantly higher rate of limb necrosis in hyperglycemic rats compared to euglycemic rats (71% versus 29%, resp.. In this study, we revealed that hyperglycemia per se increases the susceptibility to limb necrosis in ischemic conditions. Our results may help to better understand the physiopathology of progressive diabetic wounds and underline the importance of strict glycemic control in patients with critical limb ischemia.

  20. Ischemic Stroke during Pregnancy and Puerperium

    Directory of Open Access Journals (Sweden)

    Elisabetta Del Zotto

    2011-01-01

    Full Text Available Ischemic stroke during pregnancy and puerperium represents a rare occurrence but it could be a serious and stressful event for mothers, infants, and also families. Whenever it does occur, many concerns arise about the safety of the mother and the fetus in relation to common diagnostic tests and therapies leading to a more conservative approach. The physiological adaptations in the cardiovascular system and in the coagulability that accompany the pregnant state, which are more significant around delivery and in the postpartum period, likely contribute to increasing the risk of an ischemic stroke. Most of the causes of an ischemic stroke in the young may also occur in pregnant patients. Despite this, there are specific conditions related to pregnancy which may be considered when assessing this particular group of patients such as pre-eclampsia-eclampsia, choriocarcinoma, peripartum cardiomiopathy, amniotic fluid embolization, and postpartum cerebral angiopathy. This article will consider several questions related to pregnancy-associated ischemic stroke, dwelling on epidemiological and specific etiological aspects, diagnostic issue concerning the use of neuroimaging, and the related potential risks to the embryo and fetus. Therapeutic issues surrounding the use of anticoagulant and antiplatelets agents will be discussed along with the few available reports regarding the use of thrombolytic therapy during pregnancy.

  1. Surgical strategy for mild ischemic mitral insufficiency

    Institute of Scientific and Technical Information of China (English)

    GU Cheng-xiong; WEI Hua; YU Yang

    2010-01-01

    @@ To the Editor: We read with the interest the article by FAN Hong-guang and colleagues~1 having obtained outstanding early and long-term clinical outcomes of left ventricular restoration for the patients with postinfarction ventricular aneurysm and low left ventricular ejection fraction (LVEF) of mean 37.7%. We would like to comment on surgical strategy for mild ischemic mitral insufficiency.

  2. Acute ischemic stroke prognostication, comparison between ...

    African Journals Online (AJOL)

    Ossama Y. Mansour

    2014-11-20

    Nov 20, 2014 ... patients with acute ischemic stroke in comparison with the NIHSS and the GCS. ... comes; In-hospital or 30 days mortality and Modified Rankin Scale (mRS) at 3 ..... 8. Bamford J, Sandercock P, Dennis M, Burn J, Warlow C.

  3. Remnant cholesterol and ischemic heart disease

    DEFF Research Database (Denmark)

    Varbo, Anette; Nordestgaard, Børge G

    2014-01-01

    PURPOSE OF REVIEW: To review recent advances in the field of remnant cholesterol as a contributor to the development of ischemic heart disease (IHD). RECENT FINDINGS: Epidemiologic, mechanistic, and genetic studies all support a role for elevated remnant cholesterol (=cholesterol in triglyceride...

  4. The neuroprotective mechanism of brain ischemic preconditioning

    Institute of Scientific and Technical Information of China (English)

    Xiao-qian LIU; Rui SHENG; Zheng-hong QIN

    2009-01-01

    Brain ischemia is one of the most common causes of death and the leading cause of adult disability in the world. Brain ischemic pre- conditioning (BIP) refers to a transient, sublethal ischemia which results in tolerance to later, otherwise lethal, cerebral ischemia. Many attempts have been made to understand the molecular and cellular mechanisms underlying the neuroprotection offered by ischemic preconditioning. Many studies have shown that neuroprotective mechanisms may involve a series of molecular regulatory pathways including activation of the N-methyI-D-aspartate (NMDA) and adenosine receptors; activation of intracellular signaling pathways such as mitogen activated protein kinases (MAPK) and other protein kinases; upregulation of Bcl-2 and heat shock proteins (HSPs); and activation of the ubiquitin-proteasome pathway and the autophagic-lysosomal pathway. A better understanding of the processes that lead to cell death after stroke as well as of the endogenous neuroprotective mechanisms by which BIP protects against brain ischemic insults could help to develop new therapeutic strategies for this devastating neurological disease. The purpose of the present review is to summarize the neuroprotective mechanisms of BIP and to discuss the possibility of mimicking ischemic preconditioning as a new strategy for preventive treatment of ischemia.

  5. The diagnosis of transient ischemic attacks

    NARCIS (Netherlands)

    P.J. Koudstaal (Peter Jan)

    1989-01-01

    textabstractThe diagnosis of transient ischemic attack (TIA) is fraught with difficulty, since the diagnosis rests entirely upon the history of the patient's symptoms and the neurologist's skill in questioning the patient. The aim of this thesis is to investigate various measures to improve the reli

  6. Spinal cord stimulation for ischemic heart disease

    NARCIS (Netherlands)

    DeJongste, MJL

    2000-01-01

    An increasing number of patients are suffering from angina pectoris that is chronically refractory to standard anti-ischemic treatment such as pharmacological and surgical strategies. To improve the quality of life of these severely disabled patients, without adversely affecting their prognosis, a n

  7. Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes

    Directory of Open Access Journals (Sweden)

    Robert Perna

    2015-01-01

    Full Text Available Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n=172 or hemorrhagic stroke (n=112 within the past six months and were involved in a postacute neurorehabilitation program. Participants completed three months of postacute neurorehabilitation and the Mayo Portland Adaptability Inventory-4 (MPAI-4 at admission and discharge. Admission MPAI-4 scores and level of functioning were comparable. Results. Group ANOVA comparisons show no significant group differences at admission or discharge or difference in change scores. Both groups showed considerably reduced levels of productivity/employment after discharge as compared to preinjury levels. Conclusions. Though the pathophysiology of these types of strokes is different, both ultimately result in ischemic injuries, possibly accounting for lack of findings of differences between groups. In the present study, participants in both groups experienced similar functional levels across all three MPAI-4 domains both at admission and discharge. Limitations of this study include a highly educated sample and few outcome measures.

  8. Molecular Mechanisms of Renal Ischemic Conditioning Strategies

    NARCIS (Netherlands)

    Kierulf-Lassen, Casper; Nieuwenhuijs-Moeke, Gertrude J.; Krogstrup, Nicoline V.; Oltean, Mihai; Jespersen, Bente; Dor, Frank J. M. F.

    2015-01-01

    Ischemia-reperfusion injury is the leading cause of acute kidney injury in a variety of clinical settings such as renal transplantation and hypovolemic and/or septic shock. Strategies to reduce ischemia-reperfusion injury are obviously clinically relevant. Ischemic conditioning is an inherent part o

  9. P-Wave Indices and Risk of Ischemic Stroke: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    He, Jinli; Tse, Gary; Korantzopoulos, Panagiotis; Letsas, Konstantinos P; Ali-Hasan-Al-Saegh, Sadeq; Kamel, Hooman; Li, Guangping; Lip, Gregory Y H; Liu, Tong

    2017-08-01

    Atrial cardiomyopathy is associated with an increased risk of ischemic stroke. P-wave terminal force in lead V1, P-wave duration, and maximum P-wave area are electrocardiographic parameters that have been used to assess left atrial abnormalities related to developing atrial fibrillation. The aim of this systematic review and meta-analysis was to examine their values for predicting ischemic stroke risk. PubMed and EMBASE databases were searched until December 2016 for studies that evaluated the association between P-wave indices and stroke risk. Both fixed- and random-effects models were used to calculate the overall effect estimates. Ten studies examining P-wave terminal force in lead V1, P-wave duration, and maximum P-wave area were included. P-wave terminal force in lead V1 was found to be an independent predictor of stroke as both a continuous variable (odds ratio [OR] per 1 SD change, 1.18; 95% confidence interval [CI], 1.12-1.25; PP=0.01). P-wave duration was a significant predictor of incident ischemic stroke when analyzed as a categorical variable (OR, 1.86; 95% CI, 1.37-2.52; PP=0.15). Maximum P-wave area also predicted the risk of incident ischemic stroke (OR per 1 SD change, 1.10; 95% CI, 1.04-1.17). P-wave terminal force in lead V1, P-wave duration, and maximum P-wave area are useful electrocardiographic markers that can be used to stratify the risk of incident ischemic stroke. © 2017 American Heart Association, Inc.

  10. Remote Ischemic Conditioning and Renal Protection.

    Science.gov (United States)

    Giannopoulos, Georgios; Vrachatis, Dimitrios A; Panagopoulou, Vasiliki; Vavuranakis, Manolis; Cleman, Michael W; Deftereos, Spyridon

    2017-07-01

    Over the course of the last 2 decades, the concept of remote ischemic conditioning (RIC) has attracted considerable research interest, because RIC, in most of its embodiments offers an inexpensive way of protecting tissues against ischemic damage inflicted by a number of medical conditions or procedures. Acute kidney injury (AKI) is a common side effect in the context of various medical procedures, and RIC has been suggested as a means of reducing its incidence. Outcomes regarding kidney function have been reported in numerous studies that evaluated the effects of RIC in a variety of settings (eg, cardiac surgery, interventions requiring intravenous administration of contrast media). Although several individual studies have implied a beneficial effect of RIC in preserving kidney function, 3 recently published randomized controlled trials evaluating more than 1000 patients each (Effect of Remote Ischemic Preconditioning in the Cardiac Surgery, Remote Ischaemic Preconditioning for Heart Surgery, and ERICCA) were negative. However, AKI or any other index of renal function was not a stand-alone primary end point in any of these trials. On the other hand, a range of meta-analyses (each including thousands of participants) have reported mixed results, with the most recent among them showing benefit from RIC, pinpointing at the same time a number of shortcomings in published studies, adversely affecting the quality of available data. The present review provides a critical appraisal of the current state of this field of research. It is the opinion of the authors of this review that there is a clear need for a common clinical trial framework for ischemic conditioning studies. If the current babel of definitions, procedures, outcomes, and goals persists, it is most likely that soon ischemic conditioning will be "yesterday's news" with no definitive conclusions having been reached in terms of its real clinical utility.

  11. CT findings in isolated ischemic proctosigmoiditis

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Walter; Mortele, Koenraad J.; Ji, Hoon; Khurana, Bharti; Ros, Pablo R. [Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Glickman, Jonathan N. [Department of Pathology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States)

    2002-07-01

    The purpose of our study was to describe the CT features of ischemic proctosigmoiditis in correlation with clinical, laboratory, endoscopic, and histopathologic findings. Our study included seven patients with isolated ischemic proctosigmoiditis. Patients were identified by a retrospective review of all histopathologic records of colonoscopic biopsies performed during a time period of 4 years. All patients presented with left lower abdominal quadrant pain, bloody stools, and leukocytosis, and four patients had fever at the time of presentation. Four of seven patients suffered from diarrhea, one of seven was constipated and two of seven had normal stool consistency. The CT examinations were reviewed by two authors by consensus and compared with clinical and histopathologic results as well as with the initial CT diagnosis. The CT showed a wall thickening confined to the rectum and sigmoid colon in seven of seven patients, stranding of the pararectal fat in four of seven, and stranding of the perisigmoidal fat in one of seven patients. There were no enlarged lymph nodes, but five of seven patients showed coexistent diverticulosis and in three of these patients CT findings were initially misinterpreted as sigmoid diverticulitis. Endoscopies and histopathologic analyses of endoscopic biopsies confirmed non-transmural ischemic proctosigmoiditis in all patients. Isolated ischemic proctosigmoiditis often presents with unspecific CT features and potentially misleading clinical and laboratory findings. In an elderly patient or a patient with known cardiovascular risk factors the diagnosis of ischemic proctosigmoiditis should be considered when wall thickening confined to the rectum and sigmoid colon is seen that is associated with perirectal fat stranding. (orig.)

  12. Laryngeal Elevation Velocity and Aspiration in Acute Ischemic Stroke Patients

    Science.gov (United States)

    Zhang, Jing; Zhou, Yun; Wei, Na; Yang, Bo; Wang, Anxin; Zhou, Hai; Zhao, Xingquan; Wang, Yongjun; Liu, Liping; Ouyoung, Melody; Villegas, Brenda; Groher, Michael

    2016-01-01

    Objectives Aspiration after stroke has been associated with aspiration pneumonia, which contributes to increased mortality of stroke. Laryngeal elevation is a core mechanism for protection from aspiration. Few studies have explored the predictive value of laryngeal elevation velocity for aspiration after stroke. This study aimed to explore the ability of laryngeal elevation velocity to predict aspiration in patients with acute ischemic stroke. Methods This was a prospective cohort study that included consecutive acute ischemic stroke patients treated at a teaching hospital during a 10-month period. Patients underwent magnetic resonance imaging (MRI) to confirm the diagnosis of acute ischemic stroke. Patients who were at risk of aspiration and could swallow 5 ml of diluted barium (40%, w/v) for a videofluoroscopic swallowing (VFS) study were included. The association between abnormal indices in the oral and pharyngeal phase of the VFS study and aspiration was examined using univariate analyses. These indices included the lip closure, tongue movement and control, laryngeal elevation velocity and range, the latency of pharyngeal swallowing, pharyngeal transit time (PTT), abnormal epiglottis tilt, residual barium in the pharynx, and the duration of upper esophageal sphincter (UES) opening. The laryngeal elevation velocity (%/s) was calculated as the range of laryngeal elevation (%) from the resting position to the maximum superior position or to the position where the laryngeal vestibule is fully closed divided by the corresponding duration of laryngeal elevation. The range of laryngeal elevation (%) was the percentage calculated as the distance between the resting laryngeal position and the maximum superior excursion position or position where the laryngeal vestibule is fully closed divided by the distance between the resting laryngeal position and the lowest edge of the mandible. A logistic regression analysis was used to determine the predictive value for aspiration

  13. An Inflammatory Polymorphisms Risk Scoring System for the Differentiation of Ischemic Stroke Subtypes

    Science.gov (United States)

    Muiño, Elena; Krupinski, Jurek; Carrera, Caty; Gallego-Fabrega, Cristina; Montaner, Joan; Fernández-Cadenas, Israel

    2015-01-01

    Inflammation has been associated with atherothrombotic stroke and recently with cardioembolic stroke. Different genetic risk factors have been specifically associated with the subtypes of ischemic stroke (cardioembolic, atherothrombotic, and lacunar). However, there are no studies that have generated genetic risk scores for the different subtypes of ischemic stroke using polymorphisms associated with inflammation. Methods. We have analyzed 68 polymorphisms of 30 inflammatory mediator genes in 2,685 subjects: 1,987 stroke cases and 698 controls. We generated a genetic scoring system with the most significant polymorphisms weighted by the odds ratio of every polymorphism and taken into consideration the stroke subtype. Results. Three polymorphisms, rs1205 (CRP gene), rs1800779, and rs2257073 (NOS3 gene), were associated with cardioembolic stroke (p value stroke subtype (p value: 0.001) and was replicated in an independent cohort (p value: 0.017). The subjects with the highest score presented a cardioembolic stroke in 92.2% of the cases (p value: 0.002). Conclusion. The genetics of inflammatory markers is more closely associated with cardioembolic strokes than with atherothrombotic or lacunar strokes. The genetic risk scoring system could be useful in the prediction and differentiation of ischemic stroke; however, it might be specific to particular ischemic stroke subtypes. PMID:26355258

  14. Activated leukocyte cell adhesion molecule and prognosis in acute ischemic stroke.

    Science.gov (United States)

    Smedbakken, Linda; Jensen, Jesper K; Hallén, Jonas; Atar, Dan; Januzzi, James L; Halvorsen, Bente; Aukrust, Pål; Ueland, Thor

    2011-09-01

    Biomarkers predicting mortality and functional outcome in stroke may be clinically helpful in identification of patients likely to benefit from intervention. Activated leukocyte cell adhesion molecule (ALCAM) is upregulated during neuroinflammation; we investigated whether ALCAM concentrations are associated with long-term mortality after ischemic stroke. In 244 patients with acute ischemic stroke (age 69±13 years), samples of ALCAM were obtained serially from presentation to Day 5 and after 6 months. Patients with overt ischemic heart disease and atrial fibrillation were excluded. The patients were followed for 47 months with all-cause and cardiovascular mortality as end points. At follow-up, 72 patients (29%) had died, 43 due to cardiovascular causes. Patients with ALCAM in the fourth quartile (>46.8 ng/mL) at admission had a significantly poorer survival rate on univariate analysis (Pstroke severity, C-reactive protein levels, troponin T levels, and heart and/or renal failure, ALCAM levels above the fourth quartile remained an independent predictor of long-term mortality (adjusted hazard ratio, 2.05; 95% CI, 1.11 to 3.76; P=0.021) and cardiovascular mortality (adjusted hazard ratio, 2.54; 95% CI, 1.06 to 6.07; P=0.028). ALCAM levels measured at admission of acute ischemic stroke are associated with long-term mortality.

  15. An Inflammatory Polymorphisms Risk Scoring System for the Differentiation of Ischemic Stroke Subtypes

    Directory of Open Access Journals (Sweden)

    Elena Muiño

    2015-01-01

    Full Text Available Inflammation has been associated with atherothrombotic stroke and recently with cardioembolic stroke. Different genetic risk factors have been specifically associated with the subtypes of ischemic stroke (cardioembolic, atherothrombotic, and lacunar. However, there are no studies that have generated genetic risk scores for the different subtypes of ischemic stroke using polymorphisms associated with inflammation. Methods. We have analyzed 68 polymorphisms of 30 inflammatory mediator genes in 2,685 subjects: 1,987 stroke cases and 698 controls. We generated a genetic scoring system with the most significant polymorphisms weighted by the odds ratio of every polymorphism and taken into consideration the stroke subtype. Results. Three polymorphisms, rs1205 (CRP gene, rs1800779, and rs2257073 (NOS3 gene, were associated with cardioembolic stroke (p value <0.05. The score generated was only associated with the cardioembolic stroke subtype (p value: 0.001 and was replicated in an independent cohort (p value: 0.017. The subjects with the highest score presented a cardioembolic stroke in 92.2% of the cases (p value: 0.002. Conclusion. The genetics of inflammatory markers is more closely associated with cardioembolic strokes than with atherothrombotic or lacunar strokes. The genetic risk scoring system could be useful in the prediction and differentiation of ischemic stroke; however, it might be specific to particular ischemic stroke subtypes.

  16. Protection of retinal function by sulforaphane following retinal ischemic injury.

    Science.gov (United States)

    Ambrecht, Lindsay A; Perlman, Jay I; McDonnell, James F; Zhai, Yougang; Qiao, Liang; Bu, Ping

    2015-09-01

    Sulforaphane, a precursor of glucosinolate in cruciferous vegetables such as broccoli and cauliflower, has been shown to protect brain ischemic injury. In this study, we examined the effect of systemic administration of sulforaphane on retinal ischemic reperfusion injury. Intraocular pressure was elevated in two groups of C57BL/6 mice (n = 8 per group) for 45 min to induce retinal ischemic reperfusion injury. Following retinal ischemic reperfusion injury, vehicle (1% DMSO saline) or sulforaphane (25 mg/kg/day) was administered intraperitoneally daily for 5 days. Scotopic electroretinography (ERG) was used to quantify retinal function prior to and one-week after retinal ischemic insult. Retinal morphology was examined one week after ischemic insult. Following ischemic reperfusion injury, ERG a- and b-wave amplitudes were significantly reduced in the control mice. Sulforaphane treatment significantly attenuated ischemic-induced loss of retinal function as compared to vehicle treated mice. In vehicle treated mice, ischemic reperfusion injury produced marked thinning of the inner retinal layers, but the thinning of the inner retinal layers appeared significantly less with sulforaphane treatment. Thus, sulforaphane may be beneficial in the treatment of retinal disorders with ischemic reperfusion injury. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Genomic risk profiling of ischemic stroke: results of an international genome-wide association meta-analysis.

    Directory of Open Access Journals (Sweden)

    James F Meschia

    Full Text Available INTRODUCTION: Familial aggregation of ischemic stroke derives from shared genetic and environmental factors. We present a meta-analysis of genome-wide association scans (GWAS from 3 cohorts to identify the contribution of common variants to ischemic stroke risk. METHODS: This study involved 1464 ischemic stroke cases and 1932 controls. Cases were genotyped using the Illumina 610 or 660 genotyping arrays; controls, with Illumina HumanHap 550Kv1 or 550Kv3 genotyping arrays. Imputation was performed with the 1000 Genomes European ancestry haplotypes (August 2010 release as a reference. A total of 5,156,597 single-nucleotide polymorphisms (SNPs were incorporated into the fixed effects meta-analysis. All SNPs associated with ischemic stroke (P<1×10(-5 were incorporated into a multivariate risk profile model. RESULTS: No SNP reached genome-wide significance for ischemic stroke (P<5×10(-8. Secondary analysis identified a significant cumulative effect for age at onset of stroke (first versus fifth quintile of cumulative profiles based on SNPs associated with late onset, ß = 14.77 [10.85,18.68], P = 5.5×10(-12, as well as a strong effect showing increased risk across samples with a high propensity for stroke among samples with enriched counts of suggestive risk alleles (P<5×10(-6. Risk profile scores based only on genomic information offered little incremental prediction. DISCUSSION: There is little evidence of a common genetic variant contributing to moderate risk of ischemic stroke. Quintiles based on genetic loading of alleles associated with a younger age at onset of ischemic stroke revealed a significant difference in age at onset between those in the upper and lower quintiles. Using common variants from GWAS and imputation, genomic profiling remains inferior to family history of stroke for defining risk. Inclusion of genomic (rare variant information may be required to improve clinical risk profiling.

  18. Atrial fibrillation in patients with ischemic stroke

    DEFF Research Database (Denmark)

    Thygesen, Sandra Kruchov; Frost, Lars; Eagle, Kim A;

    2009-01-01

    BACKGROUND: Atrial fibrillation is a major risk factor for ischemic stroke. However, the prognostic impact of atrial fibrillation among patients with stroke is not fully clarified. We compared patient characteristics, including severity of stroke and comorbidity, quality of in-hospital care...... and outcomes in a cohort of first-time ischemic stroke patients with and without atrial fibrillation. METHODS: Based on linkage of public medical databases, we did a population-based follow-up study among 3,849 stroke patients from the County of Aarhus, Denmark admitted in the period of 2003......-2007 and prospectively registered in the Danish National Indicator Project. RESULTS: Atrial fibrillation was associated with an adverse prognostic profile but not with an overall poorer quality of in-hospital care. Patients with atrial fibrillation had a longer total length of stay (median: 15 vs 9 days), and were...

  19. [Ischemic cholangiopathy induced by extended burns].

    Science.gov (United States)

    Cohen, Laurence; Angot, Emilie; Goria, Odile; Koning, Edith; François, Arnaud; Sabourin, Jean-Christophe

    2013-04-01

    Ischemic cholangiopathy is a recently described entity occurring mainly after hepatic grafts. Very few cases after intensive care unit (ICU) for extended burn injury were reported. We report the case of a 73-year-old woman consulting in an hepatology unit, for a jaundice appearing during a hospitalisation in an intensive care unit and increasing from her leaving from ICU, where she was treated for an extended burn injury. She had no pre-existing biological features of biliary disease. Biological tests were normal. Magnetic resonance imaging acquisitions of biliary tracts pointed out severe stenosing lesions of diffuse cholangiopathy concerning intrahepatic biliary tract, mainly peri-hilar. Biopsie from the liver confirmed the diagnosis, showing a biliary cirrhosis with bile infarcts. This case is the fourth case of ischemic cholangiopathy after extended burn injury, concerning a patient without a prior history of hepatic or biliary illness and appearing after hospitalisation in intensive care unit.

  20. Cardiac Connexin 43 and Ischemic Cardioprotection

    Institute of Scientific and Technical Information of China (English)

    Jin-yi LI; Guo-qiang ZHONG; Yan HE; Yun LING

    2009-01-01

    The connexin 43 (Cx43) proteins, which is the predominant protein that can form gap junctions and non-junctional hemichannels in ventricular myocardium, are central to the cardioprotection afforded by ischemic precondi-tioning (IP) and maybe ischemic postconditioning (PC) too. Recent studies showed that recruitment of Cx43 to the mitochondria in IP might play a role in the production of reactive oxygen species (ROS) that mediates IP. The localiza-tion of Cx43 at mitochondria appears to be important for the achieved cardioprotection and opens a new door for us to reveal the exact mechanisms of ischemia/reperfusion (I/R) injury and cardioprotection, and it might be new targets of pharmacological modulator to achieved cardioprotection.

  1. Cost and Outcome in Pediatric Ischemic Stroke.

    Science.gov (United States)

    Hamilton, William; Huang, Haijuan; Seiber, Eric; Lo, Warren

    2015-10-01

    The cost of childhood stroke receives little notice. The authors examined potential drivers of cost and outcome to test whether (1) neonatal strokes cost less than childhood strokes, (2) associated diseases influence cost, (3) arterial ischemic stroke is more costly than sinovenous thrombosis, and (4) cost correlates with outcome. The authors reviewed records of 111 children who sustained arterial ischemic stroke or sinovenous thrombosis between 2005 and 2010 to identify costs for the following year. They assessed outcomes in 46 with the Recovery and Recurrence Questionnaire and the Pediatric Quality of Life Inventory. Neonatal strokes cost less than childhood stroke. Strokes associated with congenital heart disease or vasculopathy cost the most, while perinatal or idiopathic strokes cost the least. Higher costs are correlated with worse impairment and poorer quality of life. Stroke etiology significantly influences the cost of pediatric stroke. Future cost-benefit studies must consider etiology when estimating the incremental costs associated with stroke.

  2. Genetics of ischemic stroke: Indian perspective

    Directory of Open Access Journals (Sweden)

    Subhash Kaul

    2012-01-01

    Full Text Available A stroke is still a major cause of long-term disability and the third largest killer in the world after heart attack and cancer. Inherited genetic variation has been shown to play a role in its pathogenesis and therefore, there is a need to identify the culprit genetic variants. They may provide novel targets for preventive therapeutics. The most intensively investigated candidate gene is PDE4D. There are several positive replication studies of PDE4D gene with stroke. The genetic contribution to ischemic stroke risk in India has not been explored adequately. Reports on few candidate genes are available but we are still lagging behind in this aspect. Most of the reports are from Andhra Pradesh, a province in south India and a few parts of north India. PDE4D has been identified as a predisposition gene for ischemic stroke in Southern as well as the Northern population of India.

  3. [Cerebral infarction and transient ischemic attack].

    Science.gov (United States)

    Sahara, Noriyuki; Kuwashiro, Takahiro; Okada, Yasushi

    2016-04-01

    Japanese Guidelines for the Management of Stroke 2015 was published. Here, we describe several points revised from the 2009 edition about "Cerebral infarction and transient ischemic attack (TIA)". The revision points are as follows; 1. Extension of possible time window of intravenous recombinant tissue-plasminogen activator treatment (from within 3 hours to within 4.5 hours); 2. Antiplatelet therapy in acute stage (dual antiplatelet therapy (DAPT) for non-cardioembolic ischemic stroke or TIA); 3. Endovascular recanalization therapy in acute stage; 4. Antiplatelet therapy in chronic stage (Cilostazol is recommended similar to aspirin or clopidogrel); 5. Non-vitamin K antagonist oral anticoagulants (NOACs) for non-valvular atrial fibrillation (NVAF) stroke or TIA patients; 6. Management of TIA. We explain the revised points of the guideline in the text.

  4. Ischemic stroke: carotid and vertebral artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Vilela, P.; Goulao, A. [Hospital Garcia de Orta, Servico de Neurorradiologia, Almada (Portugal)

    2005-03-01

    Ischemic strokes may have distinct aetiologies, including several different intrinsic arterial pathological disorders. The diagnosis and understanding of these arterial diseases is critical for the correct management of stroke as different treatment approaches are undertaken according to the aetiology. Atherosclerosis is by far the most common arterial disease among adults, and other pathological processes include arterial dissection, small vessel disease, inflammatory and non-inflammatory vasculopathy and vasomotor disorders. In children, there are several vasculopathies responsible for vaso-occlusive disease such as sickle-cell anemia, acute regressive angiopathy and Moya-Moya disease, neurofibromatosis, dissections, vasculitis associated with intracranial and systemic infections. An overview of the major carotid and vertebral pathological diseases responsible for ischemic stroke in adults and children, highlighting the accuracy of the different imaging modalities for its diagnosis and the imaging appearance of these diseases, is given. (orig.)

  5. Antiphosphatidylserine Antibodies and Clinical Outcomes in Patients With Acute Ischemic Stroke.

    Science.gov (United States)

    Bu, Xiaoqing; Peng, Hao; Zhong, Chongke; Xu, Tan; Xu, Tian; Peng, Yanbo; Chen, Chung-Shiuan; Wang, Jinchao; Ju, Zhong; Li, Qunwei; Geng, Deqin; Sun, Yingxian; Zhang, Dongsheng; Zhang, Jintao; Chen, Jing; Zhang, Yonghong; He, Jiang

    2016-11-01

    Antiphosphatidylserine antibodies (aPS) have been associated with the risk of ischemic stroke. However, it remains unclear whether aPS will influence clinical outcomes in patients with acute ischemic stroke. A total of 3013 patients with acute ischemic stroke recruited from 26 hospitals across China from August 2009 to May 2013 were included in the study The primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3) at 3 months after stroke. Secondary outcomes included death, major disability, recurrent stroke, and vascular events. Composite outcome of death and major disability rates were 29.1% versus 23.9% in aPS-positive and aPS-negative groups. Compared with aPS-negative, adjusted odds ratios or hazard ratios (95% confidence interval) associated with aPS-positive were 1.35 (1.07-1.71), 1.63 (0.99-2.69), and 1.25 (0.98-1.59) for composite outcome of death or major disability, death, and major disability, respectively. For 1 interquartile range increase of aPS, the adjusted odds ratios or hazard ratios were 1.10 (1.01-1.20), 1.19 (1.05-1.35), and 1.05 (0.96-1.14), respectively. Adding aPS status to a model containing conventional risk factors improved risk prediction for composite outcome of death or major disability (net reclassification improvement index=11.3%, P=0.006; integrated discrimination improvement=0.2%, P=0.04). There was no significant association between aPS and risks of recurrent stroke and vascular events. We found that positive aPS increased risks of death or major disability at 3 months after an acute ischemic stroke, suggesting that aPS might be a prognostic marker for ischemic stroke. © 2016 American Heart Association, Inc.

  6. Stem Cell Therapies in Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Birsen Ince

    2017-08-01

    Full Text Available Stem cells have been a great interest in the treatment of neurological diseases. However, technical and ethical issues are still not resolved. Despite all difficulties, there has been a great effort for the translation of knowledge from animal studies to human stroke. To establish standardized protocols, guidelines have been published for the preclinical and clinical stem cell studies. This review summarizes the stem cells applications in patients with ischemic stroke in recent years.

  7. Ischemic Colitis after Weight-Loss Medication

    Directory of Open Access Journals (Sweden)

    Dan Comay

    2003-01-01

    Full Text Available BACKGROUND: Previous weight-loss medications have received cautious support due to their association with pulmonary hypertension and valvular heart disease. However, newer drugs are increasingly being recommended as potentially safer and more efficacious. We report a case of ischemic colitis possibly linked to the use of a weight-loss drug, and review the literature to highlight an important latent consequence of these medications.

  8. Ischemic Colitis in an Endurance Runner

    Directory of Open Access Journals (Sweden)

    Chase Grames

    2012-01-01

    Full Text Available A 20-year-old female running the Marine Corps Marathon developed diarrhea at mile 12. After finishing the race she noted that she was covered in bloody stool. A local emergency department suspected ischemic colitis. After discharge, her primary care physician instructed her to discontinue the use of all nonsteroidal anti-inflammatory drugs. Her symptoms resolved and she returned to running without any complications. This paper describes the pathophysiology, diagnostic approach, and management options.

  9. Promoting thrombolysis in acute ischemic stroke.

    Science.gov (United States)

    Dirks, Maaike; Niessen, Louis W; van Wijngaarden, Jeroen D H; Koudstaal, Peter J; Franke, Cees L; van Oostenbrugge, Robert J; Huijsman, Robbert; Lingsma, Hester F; Minkman, Mirella M N; Dippel, Diederik W J

    2011-05-01

    Thrombolysis with intravenous recombinant tissue plasminogen activator is an effective treatment for acute ischemic stroke, but the number of treatable patients is limited. The PRomoting ACute Thrombolysis in Ischemic StrokE (PRACTISE) trial evaluated the effectiveness of a multidimensional implementation strategy for thrombolysis with intravenous recombinant tissue plasminogen activator in acute ischemic stroke. The PRACTISE trial was a national multicenter cluster-randomized controlled trial with randomization after pairwise matching. Twelve hospitals, both urban and community, academic and nonacademic, in the Netherlands participated. All patients admitted with stroke within 24 hours from onset of symptoms were registered. The intervention included 5 implementation meetings based on the Breakthrough Series model. The primary outcome was treatment with thrombolysis. Secondary outcomes were admission within 4 hours after onset of symptoms, death or disability at 3 months, and quality of life. Overall 5515 patients were included in the study' 308 patients (12.2%) in the control centers and 393 patients (13.1%) in the intervention centers were treated with thrombolysis (adjusted OR, 1.25; 95% CI, 0.93 to 1.68). Among the 1657 patients with ischemic stroke admitted within 4 hours from onset, 391 (44.5%) of 880 in the intervention centers were treated with thrombolysis and 305 (39.3%) of 777 in the control centers; the adjusted OR for treatment with thrombolysis was 1.58 (95% CI, 1.11 to 2.27). An intensive implementation strategy increases the proportion of patients with acute stroke treated with thrombolysis in real-life settings. An apparently pivotal factor in the improvement of the treatment rate is better application of contraindications for thrombolysis.

  10. Hydrophilic Polymer-associated Ischemic Enterocolitis.

    Science.gov (United States)

    Chavez, Jesus A; Chen, Wei; Frankel, Wendy L; Arnold, Christina A

    2017-02-01

    Hydrophilic polymer coating of medical devices serves to lubricate the device and prevent device-related complications. The coating can be mechanically disrupted and result in downstream injury via presumed thromboembolism. This process has been reported in the brain, heart, lung, and skin, and has been replicated through animal studies and in vitro histologic processing of the polymer coating. We report the first description of hydrophilic polymer-associated ischemic enterocolitis in a series of 7 specimens (small bowel=2, colon=4, aortic thrombus=1) from 3 patients. We report a 4% incidence among all patients with an ischemic bowel resection between April 29, 2014 and August 8, 2016. All patients developed bowel ischemia within 1 day of aortic repair, and all bowel resection specimens showed polymers, mainly in the submucosal vessels in areas of extensive ischemia. The polymers appeared as basophilic, intravascular, serpiginous structures. In a patient who developed acute paralysis after the aortic repair, identical polymers were identified in the aortic thrombus and the ischemic bowel segment. We demonstrate that the polymers display an altered morphology over time and with various graft types, and that the degrading polymers are associated with a foreign body giant cell reaction. Special stains can aid in diagnosis, with the polymers turquoise on a colloidal iron stain, pink on von Kossa and mucicarmine stains, and pale blue on trichrome. Clinical follow-up was available up to 115 weeks: 1 patient died, and 2 are alive and well. In summary, we report a new diagnostic entity to be considered in the differential diagnosis of iatrogenic ischemic injuries in the gastrointestinal tract. Awareness of this entity is important to elucidate the cause of ischemia and to prevent misdiagnosis of the polymers and their associated giant cell reaction as a parasitic infection, granulomatous vasculitis, sarcoidosis, and idiopathic inflammatory bowel disease.

  11. Molecular chaperones and hypoxic-ischemic encephalopathy

    Directory of Open Access Journals (Sweden)

    Cong Hua

    2017-01-01

    Full Text Available Hypoxic-ischemic encephalopathy (HIE is a disease that occurs when the brain is subjected to hypoxia, resulting in neuronal death and neurological deficits, with a poor prognosis. The mechanisms underlying hypoxic-ischemic brain injury include excitatory amino acid release, cellular proteolysis, reactive oxygen species generation, nitric oxide synthesis, and inflammation. The molecular and cellular changes in HIE include protein misfolding, aggregation, and destruction of organelles. The apoptotic pathways activated by ischemia and hypoxia include the mitochondrial pathway, the extrinsic Fas receptor pathway, and the endoplasmic reticulum stress-induced pathway. Numerous treatments for hypoxic-ischemic brain injury caused by HIE have been developed over the last half century. Hypothermia, xenon gas treatment, the use of melatonin and erythropoietin, and hypoxic-ischemic preconditioning have proven effective in HIE patients. Molecular chaperones are proteins ubiquitously present in both prokaryotes and eukaryotes. A large number of molecular chaperones are induced after brain ischemia and hypoxia, among which the heat shock proteins are the most important. Heat shock proteins not only maintain protein homeostasis; they also exert anti-apoptotic effects. Heat shock proteins maintain protein homeostasis by helping to transport proteins to their target destinations, assisting in the proper folding of newly synthesized polypeptides, regulating the degradation of misfolded proteins, inhibiting the aggregation of proteins, and by controlling the refolding of misfolded proteins. In addition, heat shock proteins exert anti-apoptotic effects by interacting with various signaling pathways to block the activation of downstream effectors in numerous apoptotic pathways, including the intrinsic pathway, the endoplasmic reticulum-stress mediated pathway and the extrinsic Fas receptor pathway. Molecular chaperones play a key role in neuroprotection in HIE. In

  12. Migraine and risk of perioperative ischemic stroke and hospital readmission: hospital based registry study

    Science.gov (United States)

    Timm, Fanny P; Houle, Timothy T; Grabitz, Stephanie D; Lihn, Anne-Louise; Stokholm, Janne B; Eikermann-Haerter, Katharina; Nozari, Ala; Kurth, Tobias

    2017-01-01

    Objective To evaluate whether patients with migraine are at increased risk of perioperative ischemic stroke and whether this may lead to an increased hospital readmission rate. Design Prospective hospital registry study. Setting Massachusetts General Hospital and two satellite campuses between January 2007 and August 2014. Participants 124 558 surgical patients (mean age 52.6 years; 54.5% women). Main outcome measures The primary outcome was perioperative ischemic stroke occurring within 30 days after surgery in patients with and without migraine and migraine aura. The secondary outcome was hospital readmission within 30 days of surgery. Exploratory outcomes included post-discharge stroke and strata of neuroanatomical stroke location. Results 10 179 (8.2%) patients had any migraine diagnosis, of whom 1278 (12.6%) had migraine with aura and 8901 (87.4%) had migraine without aura. 771 (0.6%) perioperative ischemic strokes occurred within 30 days of surgery. Patients with migraine were at increased risk of perioperative ischemic stroke (adjusted odds ratio 1.75, 95% confidence interval 1.39 to 2.21) compared with patients without migraine. The risk was higher in patients with migraine with aura (adjusted odds ratio 2.61, 1.59 to 4.29) than in those with migraine without aura (1.62, 1.26 to 2.09). The predicted absolute risk is 2.4 (2.1 to 2.8) perioperative ischemic strokes for every 1000 surgical patients. This increases to 4.3 (3.2 to 5.3) for every 1000 patients with any migraine diagnosis, 3.9 (2.9 to 5.0) for migraine without aura, and 6.3 (3.2 to 9.5) for migraine with aura.Patients with migraine had a higher rate of readmission to hospital within 30 days of discharge (adjusted odds ratio 1.31, 1.22 to 1.41). Conclusions Surgical patients with a history of migraine are at increased risk of perioperative ischemic stroke and have an increased 30 day hospital readmission rate. Migraine should be considered in the risk assessment for perioperative

  13. Identification of Blood Let-7e-5p as a Biomarker for Ischemic Stroke

    Science.gov (United States)

    Guo, Yi; Li, Lu; Zhang, Yanwei; Zhou, Li; Yang, Binyao; Wu, Shuang; Zhang, Ying; Xie, Changhui; Li, Shanshan; Cheng, Jinquan

    2016-01-01

    Circulating microRNAs (miRNAs) are emerging as novel disease biomarkers. Using a miRNA microarray, we previously showed that the whole blood level of let-7e-5p was significantly higher in ischemic stroke patients than in control subjects. However, the association between let-7e-5p expression and the occurrence of ischemic stroke remains unknown. In this study, we validated the expression levels of let-7e-5p in two case-control populations using miRNA TaqMan assays and further investigated the potential targets of let-7e-5p. The results suggest that the blood level of let-7e-5p was significantly higher in patients with ischemic stroke than in controls (p<0.05). Higher levels of let-7e-5p were associated with increased occurrence of ischemic stroke (adjusted OR, 1.89; 95% CI, 1.61~2.21, p<0.001) in the combined population. The addition of let-7e-5p to traditional risk factors led to an improvement in the area under the curve, which increased from 0.74 (95% CI, 0.70~0.78) to 0.82 (95% CI, 0.78~0.85), with a net reclassification improvement of 16.76% (p<0.0001) and an integrated discrimination improvement of 0.10 (p<0.0001) for patients with ischemic stroke. Bioinformatics prediction and cell experiments suggested that the expression levels of four genes enriched in the MAPK signaling pathway were down-regulated by let-7e-5p transfection. Specifically, the expression levels of the genes CASP3 and NLK were significantly lower in ischemic stroke patients than in controls and were negatively correlated with let-7e-5p expression. In summary, our study suggests the potential use of blood let-7e-5p as a biomarker for ischemic stroke and indicates its involvement in the related pathomechanism. PMID:27776139

  14. Genetic Predisposition to Ischemic Stroke: A Polygenic Risk Score.

    Science.gov (United States)

    Hachiya, Tsuyoshi; Kamatani, Yoichiro; Takahashi, Atsushi; Hata, Jun; Furukawa, Ryohei; Shiwa, Yuh; Yamaji, Taiki; Hara, Megumi; Tanno, Kozo; Ohmomo, Hideki; Ono, Kanako; Takashima, Naoyuki; Matsuda, Koichi; Wakai, Kenji; Sawada, Norie; Iwasaki, Motoki; Yamagishi, Kazumasa; Ago, Tetsuro; Ninomiya, Toshiharu; Fukushima, Akimune; Hozawa, Atsushi; Minegishi, Naoko; Satoh, Mamoru; Endo, Ryujin; Sasaki, Makoto; Sakata, Kiyomi; Kobayashi, Seiichiro; Ogasawara, Kuniaki; Nakamura, Motoyuki; Hitomi, Jiro; Kita, Yoshikuni; Tanaka, Keitaro; Iso, Hiroyasu; Kitazono, Takanari; Kubo, Michiaki; Tanaka, Hideo; Tsugane, Shoichiro; Kiyohara, Yutaka; Yamamoto, Masayuki; Sobue, Kenji; Shimizu, Atsushi

    2017-02-01

    The prediction of genetic predispositions to ischemic stroke (IS) may allow the identification of individuals at elevated risk and thereby prevent IS in clinical practice. Previously developed weighted multilocus genetic risk scores showed limited predictive ability for IS. Here, we investigated the predictive ability of a newer method, polygenic risk score (polyGRS), based on the idea that a few strong signals, as well as several weaker signals, can be collectively informative to determine IS risk. We genotyped 13 214 Japanese individuals with IS and 26 470 controls (derivation samples) and generated both multilocus genetic risk scores and polyGRS, using the same derivation data set. The predictive abilities of each scoring system were then assessed using 2 independent sets of Japanese samples (KyushuU and JPJM data sets). In both validation data sets, polyGRS was shown to be significantly associated with IS, but weighted multilocus genetic risk scores was not. Comparing the highest with the lowest polyGRS quintile, the odds ratios for IS were 1.75 (95% confidence interval, 1.33-2.31) and 1.99 (95% confidence interval, 1.19-3.33) in the KyushuU and JPJM samples, respectively. Using the KyushuU samples, the addition of polyGRS to a nongenetic risk model resulted in a significant improvement of the predictive ability (net reclassification improvement=0.151; Pgenetic risk scores as an IS prediction model. Thus, together with the nongenetic risk factors, polyGRS will provide valuable information for individual risk assessment and management of modifiable risk factors. © 2016 The Authors.

  15. Neurovascular Regulation in the Ischemic Brain

    Science.gov (United States)

    Jackman, Katherine

    2015-01-01

    Abstract Significance: The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. Recent Advances and Critical Issues: The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Future Directions: Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory. Antioxid. Redox Signal. 22, 149–160. PMID:24328757

  16. Obstructive sleep apnea in ischemic stroke patients

    Directory of Open Access Journals (Sweden)

    Aliye Tosun

    2008-01-01

    Full Text Available OBJECTIVE: To investigate the prevalence of obstructive sleep apnea in patients with ischemic stroke and to evaluate the effectiveness of nasal continuous positive airway pressure treatment. METHODS: Overnight polysomnography was performed by a computerized system in 19 subjects with ischemic stroke. Patients with an apnea-hypopnea index > 5 were considered to have obstructive sleep apnea. The appropriate level of continuous positive airway pressure for each patient was determined during an all-night continuous positive airway pressure determination study. Attended continuous positive airway pressure titration was performed with a continuous positive airway pressure auto-titrating device. RESULTS: Obstructive sleep apnea prevalence among patients with ischemic stroke was 73.7%. The minimum SaO2 was significantly lower, and the percent of total sleep time in the wake stage and stage 1 sleep was significantly longer in patients with obstructive sleep apnea. In two patients with severe obstructive sleep apnea, we observed a decrease in the apnea-hypopnea index, an increase in mean wake time, mean SaO2, and minimum SaO2, and alterations in sleep structures with continuous positive airway pressure treatment. CONCLUSION: As the diagnosis and treatment of obstructive sleep apnea is of particular importance in secondary stroke prevention, we suggest that the clinical assessment of obstructive sleep apnea be part of the evaluation of stroke patients in rehabilitation units, and early treatment should be started.

  17. TOWARD THE QUESTION OF ISCHEMIC MYOCARDIAL DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    V. V. Kalyuzhin

    2014-01-01

    Full Text Available The authors of the review have analyzed papers published on the problem of ischemic myocardial dysfunction. They begin with a definition of the term “ischemia” (derived from two Greek words: ischō, meaning to hold back, and haima, meaning blood - a condition at which the arterial blood flow is insufficient to provide enough oxygen to prevent intracellular respiration from shifting from the aerobic to the anaerobic form. The poor rate of ATP generation from this process causes a decrease in cellular ATP, a concomitant rise in ADP, and ultimately, to depression inotropic (systolic and lusitropic (diastolic function of the affected segments of the myocardium. But with such simplicity of basic concepts, the consequences of ischemia so diverse. Influence of an ischemia on myocardial function so unequally at different patients, which is almost impossible to find two identical cases (as in the case of fingerprints. It depends on the infinite variety of lesions of coronary arteries, reperfusion (time and completeness of restoration of blood flow and reactions of a myocardium which, apparently, has considerable flexibility in its response. Ischemic myocardial dysfunction includes a number of discrete states, such as acute left ventricular failure in angina, acute myocardial infarction, ischemic cardiomyopathy, stunning, hibernation, pre- and postconditioning. There are widely differing underlying pathophysiologic states. The possibility exists that several of these states can coexist.

  18. Blood Pressure in Acute Ischemic Stroke

    Science.gov (United States)

    McManus, Michael

    2016-01-01

    Hypertension is present in up to 84% of patients presenting with acute stroke, and a smaller proportion of patients have blood pressures that are below typical values in the context of cerebral ischemia. Outcomes are generally worse in those who present with either low or severely elevated blood pressure. Several studies have provided valuable information about malignant trends in blood pressure during the transition from the acute to the subacute phase of stroke. It is not uncommon for practitioners in clinical practice to identify what appear to be pressure-dependent neurologic deficits. Despite physiologic and clinical data suggesting the importance of blood pressure modulation to support cerebral blood flow to ischemic tissue, randomized controlled trials have not yielded robust evidence for this in acute ischemic stroke. We highlight previous studies involving acute-stroke patients that have defined trends in blood pressure and that have evaluated the safety and efficacy of blood-pressure modulation in acute ischemic stroke. This overview reports the current status of this topic from the perspective of a stroke neurologist and provides a framework for future research. PMID:26833984

  19. Ischemic preconditioning—an unfulfilled promise

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Timothy M. [Ashford & St. Peter' s Hospitals NHS Foundation Trust, Guildford Road, Surrey, KT16 0PZ (United Kingdom); Waksman, Ron [Washington Hospital Centre, 110 Irving Street, Washington, DC 20010 (United States); De Silva, Kalpa; Jacques, Adam [Ashford & St. Peter' s Hospitals NHS Foundation Trust, Guildford Road, Surrey, KT16 0PZ (United Kingdom); Mahmoudi, Michael, E-mail: m.mahmoudi@surrey.ac.uk [Ashford & St. Peter' s Hospitals NHS Foundation Trust, Guildford Road, Surrey, KT16 0PZ (United Kingdom); University of Surrey, 13AY04, Surrey, GU2 7XH (United Kingdom)

    2015-03-15

    Myocardial reperfusion injury has been identified as a key determinant of myocardial infarct size in patients undergoing percutaneous or surgical interventions. Although the molecular mechanisms underpinning reperfusion injury have been elucidated, attempts at translating this understanding into clinical benefit for patients undergoing cardiac interventions have produced mixed results. Ischemic conditioning has been applied before, during, or after an ischemic insult to the myocardium and has taken the form of local induction of ischemia or ischemia of distant tissues. Clinical studies have confirmed the safety of differing conditioning techniques, but the benefit of such techniques in reducing hard clinical event rates has produced mixed results. The aim of this article is to review the role of ischemic conditioning in patients undergoing percutaneous and surgical coronary revascularization. - Highlights: • There are a multitude of techniques for conditioning. • Conditioning has been utilized in percutaneous coronary intervention and cardiac surgery. • There is a lack of consistency in the techniques utilized and outcomes that have been measured. • The results of studies to date lack a consistency in the benefits of conditioning.

  20. Acute ischemic stroke prognostication, comparison between Glasgow Coma Score, NIHS Scale and Full Outline of UnResponsiveness Score in intensive care unit

    Directory of Open Access Journals (Sweden)

    Ossama Y. Mansour

    2015-09-01

    Conclusions: The GCS and the FOUR score are accurate predictors of mortality after acute ischemic stroke, and are equal in prediction to the NIHSS. The NIHSS is more accurate than the GCS and the FOUR score in predicting poor neurologic outcome.

  1. Cardioprotection by remote ischemic conditioning: Mechanisms and clinical evidences

    Institute of Scientific and Technical Information of China (English)

    Alberto; Aimo; Chiara; Borrelli; Alberto; Giannoni; Luigi; Emilio; Pastormerlo; Andrea; Barison; Gianluca; Mirizzi; Michele; Emdin; Claudio; Passino

    2015-01-01

    In remote ischemic conditioning(RIC), several cycles of ischemia and reperfusion render distant organ and tissues more resistant to the ischemia-reperfusion injury. The intermittent ischemia can be applied before the ischemic insult in the target site(remote ischemic preconditioning), during the ischemic insult(remote ischemic perconditioning) or at the onset of reperfusion(remote ischemic postconditioning). The mechanisms of RIC have not been completely defined yet; however, these mechanisms must be represented by the release of humoral mediators and/or the activation of a neural reflex. RIC has been discovered in the heart, and has been arising great enthusiasm in the cardiovascular field. Its efficacy has been evaluated in many clinical trials, which provided controversial results. Our incomplete comprehension of the mechanisms underlying the RIC could be impairing the design of clinical trials and the interpretation of their results. In the present review we summarize current knowledge about RIC pathophysiology and the data about its cardioprotective efficacy.

  2. Impaired mitochondrial function in chronically ischemic human heart

    DEFF Research Database (Denmark)

    Stride, Nis Ottesen; Larsen, Steen; Hey-Mogensen, Martin

    2013-01-01

    mitochondrial damage, hereby reinforcing a vicious circle. Ischemic preconditioning has been proven protective in acute ischemia, but the subject of chronic ischemic preconditioning has not been explored in humans. We hypothesized that mitochondrial respiratory capacity would be diminished in chronic ischemic...... regions of human myocardium but that these mitochondria would be more resistant to ex vivo ischemia and, second, that ROS generation would be higher in ischemic myocardium. The aim of this study was to test mitochondrial respiratory capacity during hyperoxia and hypoxia, to investigate ROS production......, and finally to assess myocardial antioxidant levels. Mitochondrial respiration in biopsies from ischemic and nonischemic regions from the left ventricle of the same heart was compared in nine human subjects. Maximal oxidative phosphorylation capacity in fresh muscle fibers was lower in ischemic compared...

  3. Frequency of craniofacial pain in patients with ischemic heart disease

    OpenAIRE

    Bakhshi, Mahin; Rezaei, Rezvan; Baharvand, Maryam; Bakhtiari, Sedigheh

    2017-01-01

    Background Referred craniofacial pain of cardiac origin might be the only symptom of ischemic heart accidents. This study aimed to determine the frequency of craniofacial pain in patients with ischemic heart disease. Material and Methods This cross-sectional study was accomplished on 296 patients who met the criteria of having ischemic heart disease. Data regarding demographics, medical history and referred craniofacial pain were recorded in data forms. In addition, patients underwent oral ex...

  4. Neonatal ischemic brain injury: what every radiologist needs to know

    Energy Technology Data Exchange (ETDEWEB)

    Badve, Chaitra A.; Khanna, Paritosh C.; Ishak, Gisele E. [Seattle Children' s Hospital, University of Washington Medical Center, Department of Radiology, Seattle, WA (United States)

    2012-05-15

    We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested. (orig.)

  5. Osteoporosis and ischemic cardiovascular disease.

    Science.gov (United States)

    Laroche, Michel; Pécourneau, Virginie; Blain, Hubert; Breuil, Véronique; Chapurlat, Roland; Cortet, Bernard; Sutter, Bruno; Degboe, Yannick

    2016-11-09

    Osteoporosis and cardiovascular disease were long viewed as independent of each other. However, numerous epidemiological studies, which are discussed in the first part of this review, have provided incontrovertible evidence of a link. Thus, the risk of coronary artery disease and stroke is higher in patients with a history of osteoporotic fracture or low bone mineral density than in non-osteoporotic patients. In the other direction, patients with cardiovascular disease are at higher risk for bone loss and osteoporotic fracture. The link between osteoporosis and cardiovascular disease is due in part to shared conventional risk factors such as estrogen deprivation in women, smoking, low physical activity, and diabetes. In addition, atheroma plaque calcification involves cytokines and growth factors that also play a role in bone turnover, including proinflammatory cytokines (IL-6 and TNFα), osteoprotegerin, sclerostin, matrix GLA protein, and FGF-23. Several recent studies have provided support for these pathophysiological hypotheses. Thus, elevation of osteoprotegerin, sclerostin, or FGF-23 levels may explain and predict the occurrence of both osteoporotic fractures and cardiovascular events. The association between osteoporosis and cardiovascular disease found in most epidemiological and pathophysiological studies suggests a need for evaluating potential benefits from routine bone absorptiometry and osteoporotic fracture detection in patients with cardiovascular disease and from exercise testing and arterial Doppler imaging in patients with osteoporosis.

  6. The Influence of Diabetes Mellitus in Myocardial Ischemic Preconditioning

    Directory of Open Access Journals (Sweden)

    Paulo Cury Rezende

    2016-01-01

    Full Text Available Ischemic preconditioning (IP is a powerful mechanism of protection discovered in the heart in which ischemia paradoxically protects the myocardium against other ischemic insults. Many factors such as diseases and medications may influence IP expression. Although diabetes poses higher cardiovascular risk, the physiopathology underlying this condition is uncertain. Moreover, although diabetes is believed to alter intracellular pathways related to myocardial protective mechanisms, it is still controversial whether diabetes may interfere with ischemic preconditioning and whether this might influence clinical outcomes. This review article looks at published reports with animal models and humans that tried to evaluate the possible influence of diabetes in myocardial ischemic preconditioning.

  7. The Influence of Diabetes Mellitus in Myocardial Ischemic Preconditioning.

    Science.gov (United States)

    Rezende, Paulo Cury; Rahmi, Rosa Maria; Hueb, Whady

    Ischemic preconditioning (IP) is a powerful mechanism of protection discovered in the heart in which ischemia paradoxically protects the myocardium against other ischemic insults. Many factors such as diseases and medications may influence IP expression. Although diabetes poses higher cardiovascular risk, the physiopathology underlying this condition is uncertain. Moreover, although diabetes is believed to alter intracellular pathways related to myocardial protective mechanisms, it is still controversial whether diabetes may interfere with ischemic preconditioning and whether this might influence clinical outcomes. This review article looks at published reports with animal models and humans that tried to evaluate the possible influence of diabetes in myocardial ischemic preconditioning.

  8. Ischemic postconditioning protects against ischemic brain injury by up-regulation of acid-sensing ion channel 2a

    Institute of Scientific and Technical Information of China (English)

    Wang-sheng Duanmu; Liu Cao; Jing-yu Chen; Hong-fei Ge; Rong Hu; Hua Feng

    2016-01-01

    Ischemic postconditioning renders brain tissue tolerant to brain ischemia, thereby alleviating ischemic brain injury. However, the exact mechanism of action is still unclear. In this study, a rat model of global brain ischemia was subjected to ischemic postconditioning treat-ment using the vessel occlusion method. After 2 hours of ischemia, the bilateral common carotid arteries were blocked immediately for 10 seconds and then perfused for 10 seconds. This procedure was repeated six times. Ischemic postconditioning was found to mitigate hippocampal CA1 neuronal damage in rats with brain ischemia, and up-regulate acid-sensing ion channel 2a expression at the mRNA and protein level. These ifndings suggest that ischemic postconditioning up-regulates acid-sensing ion channel 2a expression in the rat hippo-campus after global brain ischemia, which promotes neuronal tolerance to ischemic brain injury.

  9. Influence of premorbid psychopathology and lesion location on affective and behavioral disorders after ischemic stroke.

    Science.gov (United States)

    Castellanos-Pinedo, Fernando; Hernández-Pérez, José María; Zurdo, Martín; Rodríguez-Fúnez, Beatriz; Hernández-Bayo, José María; García-Fernández, Ciara; Cueli-Rincón, Bernardo; Castro-Posada, Juan Antonio

    2011-01-01

    Early recognition of psychopathological symptoms (PSs) after stroke is important because they greatly influence the recovery of patients. The aim of this study was to investigate the predictive factors of PSs occurring in patients with ischemic stroke. Eighty-nine patients were prospectively evaluated upon admission and 4, 12, and 26 weeks later with the Neuropsychiatric Inventory, Hamilton's Rating Scales for Depression and Anxiety, and a battery of neuropsychological and functional scales. Depression and apathy were the most frequent PSs detected after stroke. Premorbid psychopathologies and right-hemisphere location were the main predictive indicators of early and long-term PSs.

  10. Neural stem cells may be uniquely suited for combined gene therapy and cell replacement: Evidence from engraftment of Neurotrophin-3-expressing stem cells in hypoxic-ischemic brain injury.

    Science.gov (United States)

    Park, Kook In; Himes, B Timothy; Stieg, Philip E; Tessler, Alan; Fischer, Itzhak; Snyder, Evan Y

    2006-05-01

    Previously, we reported that, when clonal neural stem cells (NSCs) were transplanted into brains of postnatal mice subjected to unilateral hypoxic-ischemic (HI) injury (optimally 3-7 days following infarction), donor-derived cells homed preferentially (from even distant locations) to and integrated extensively within the large ischemic areas that spanned the hemisphere. A subpopulation of NSCs and host cells, particularly in the penumbra, "shifted" their differentiation towards neurons and oligodendrocytes, the cell types typically damaged following asphyxia and least likely to regenerate spontaneously and in sufficient quantity in the "post-developmental" CNS. That no neurons and few oligodendrocytes were generated from the NSCs in intact postnatal cortex suggested that novel signals are transiently elaborated following HI to which NSCs might respond. The proportion of "replacement" neurons was approximately 5%. Neurotrophin-3 (NT-3) is known to play a role in inducing neuronal differentiation during development and perhaps following injury. We demonstrated that NSCs express functional TrkC receptors. Furthermore, the donor cells continued to express a foreign reporter transgene robustly within the damaged brain. Therefore, it appeared feasible that neuronal differentiation of exogenous NSCs (as well as endogenous progenitors) might be enhanced if donor NSCs were engineered prior to transplantation to (over)express a bioactive gene such as NT-3. A subclone of NSCs transduced with a retrovirus encoding NT-3 (yielding >90% neurons in vitro) was implanted into unilaterally asphyxiated postnatal day 7 mouse brain (emulating one of the common causes of cerebral palsy). The subclone expressed NT-3 efficiently in vivo. The proportion of NSC-derived neurons increased to approximately 20% in the infarction cavity and >80% in the penumbra. The neurons variously differentiated further into cholinergic, GABAergic, or glutamatergic subtypes, appropriate to the cortex. Donor

  11. Type 2 diabetes, glucose, insulin, BMI, and ischemic stroke subtypes: Mendelian randomization study.

    Science.gov (United States)

    Larsson, Susanna C; Scott, Robert A; Traylor, Matthew; Langenberg, Claudia C; Hindy, George; Melander, Olle; Orho-Melander, Marju; Seshadri, Sudha; Wareham, Nicholas J; Markus, Hugh S

    2017-08-01

    To implement a mendelian randomization (MR) approach to determine whether type 2 diabetes mellitus (T2D), fasting glucose, fasting insulin, and body mass index (BMI) are causally associated with specific ischemic stroke subtypes. MR estimates of the association between each possible risk factor and ischemic stroke subtypes were calculated with inverse-variance weighted (conventional) and weighted median approaches, and MR-Egger regression was used to explore pleiotropy. The number of single nucleotide polymorphisms (SNPs) used as instrumental variables was 49 for T2D, 36 for fasting glucose, 18 for fasting insulin, and 77 for BMI. Genome-wide association study data of SNP-stroke associations were derived from METASTROKE and the Stroke Genetics Network (n = 18,476 ischemic stroke cases and 37,296 controls). Conventional MR analysis showed associations between genetically predicted T2D and large artery stroke (odds ratio [OR] 1.28, 95% confidence interval [CI] 1.16-1.40, p = 3.3 × 10(-7)) and small vessel stroke (OR 1.21, 95% CI 1.10-1.33, p = 8.9 × 10(-5)) but not cardioembolic stroke (OR 1.06, 95% CI 0.97-1.15, p = 0.17). The association of T2D with large artery stroke but not small vessel stroke was consistent in a sensitivity analysis using the weighted median method, and there was no evidence of pleiotropy. Genetically predicted fasting glucose and fasting insulin levels and BMI were not statistically significantly associated with any ischemic stroke subtype. This study provides support that T2D may be causally associated with large artery stroke. © 2017 American Academy of Neurology.

  12. Ischemic stroke assessment with near-infrared spectroscopy

    Science.gov (United States)

    Chen, Weiguo; Li, Pengcheng; Zeng, Shaoqun; Luo, Qingming; Hu, Bo

    1999-09-01

    Many authors have elucidated the theory about oxygenated hemoglobin, deoxygenated hemoglobin absorption in near-infrared spectrum. And the theory has opened a window to measure the hemodynamic changes caused by stroke. However, no proper animal model still has established to confirm the theory. The aim of this study was to validate near-infrared cerebral topography (NCT) as a practical tool and to try to trace the focal hemodynamic changes of ischemic stroke. In the present study, middle cerebral artery occlusion model and the photosensitizer induced intracranial infarct model had been established. NCT and functional magnetic resonance image (fMRI) were obtained during pre- and post-operation. The geometric shape and infarct area of NCT image was compared with the fMRI images and anatomical samples of each rat. The results of two occlusion models in different intervene factors showed the NCT for infarct focus matched well with fMRI and anatomic sample of each rats. The instrument might become a practical tool for short-term prediction of stroke and predicting the rehabilitation after stroke in real time.

  13. Antithrombotic and Thrombolytic Therapy for Ischemic Stroke

    Science.gov (United States)

    Lansberg, Maarten G.; O’Donnell, Martin J.; Khatri, Pooja; Lang, Eddy S.; Nguyen-Huynh, Mai N.; Schwartz, Neil E.; Sonnenberg, Frank A.; Schulman, Sam; Vandvik, Per Olav; Spencer, Frederick A.; Alonso-Coello, Pablo; Guyatt, Gordon H.

    2012-01-01

    Objectives: This article provides recommendations on the use of antithrombotic therapy in patients with stroke or transient ischemic attack (TIA). Methods: We generated treatment recommendations (Grade 1) and suggestions (Grade 2) based on high (A), moderate (B), and low (C) quality evidence. Results: In patients with acute ischemic stroke, we recommend IV recombinant tissue plasminogen activator (r-tPA) if treatment can be initiated within 3 h (Grade 1A) or 4.5 h (Grade 2C) of symptom onset; we suggest intraarterial r-tPA in patients ineligible for IV tPA if treatment can be initiated within 6 h (Grade 2C); we suggest against the use of mechanical thrombectomy (Grade 2C) although carefully selected patients may choose this intervention; and we recommend early aspirin therapy at a dose of 160 to 325 mg (Grade 1A). In patients with acute stroke and restricted mobility, we suggest the use of prophylactic-dose heparin or intermittent pneumatic compression devices (Grade 2B) and suggest against the use of elastic compression stockings (Grade 2B). In patients with a history of noncardioembolic ischemic stroke or TIA, we recommend long-term treatment with aspirin (75-100 mg once daily), clopidogrel (75 mg once daily), aspirin/extended release dipyridamole (25 mg/200 mg bid), or cilostazol (100 mg bid) over no antiplatelet therapy (Grade 1A), oral anticoagulants (Grade 1B), the combination of clopidogrel plus aspirin (Grade 1B), or triflusal (Grade 2B). Of the recommended antiplatelet regimens, we suggest clopidogrel or aspirin/extended-release dipyridamole over aspirin (Grade 2B) or cilostazol (Grade 2C). In patients with a history of stroke or TIA and atrial fibrillation we recommend oral anticoagulation over no antithrombotic therapy, aspirin, and combination therapy with aspirin and clopidogrel (Grade 1B). Conclusions: These recommendations can help clinicians make evidence-based treatment decisions with their patients who have had strokes. PMID:22315273

  14. Gene Variants Associated With Ischemic Stroke

    Science.gov (United States)

    Luke, May M.; O’Meara, Ellen S.; Rowland, Charles M.; Shiffman, Dov; Bare, Lance A.; Arellano, Andre R.; Longstreth, W.T.; Lumley, Thomas; Rice, Kenneth; Tracy, Russell P.; Devlin, James J.; Psaty, Bruce M.

    2010-01-01

    Background and Purpose The purpose of this study was to determine whether 74 single nucleotide polymorphisms (SNPs), which had been associated with coronary heart disease, are associated with incident ischemic stroke. Methods Based on antecedent studies of coronary heart disease, we prespecified the risk allele for each of the 74 SNPs. We used Cox proportional hazards models that adjusted for traditional risk factors to estimate the associations of these SNPs with incident ischemic stroke during 14 years of follow-up in a population-based study of older adults: the Cardiovascular Health Study (CHS). Results In white CHS participants, the prespecified risk alleles of 7 of the 74 SNPs (in HPS1, ITGAE, ABCG2, MYH15, FSTL4, CALM1, and BAT2) were nominally associated with increased risk of stroke (one-sided PDMXL2, and ABCG2) were nominally associated with stroke (one-sided P<0.05, false discovery rate=0.55). The Val12Met SNP in ABCG2 was associated with stroke in both white (hazard ratio, 1.46; 90% CI, 1.05 to 2.03) and black (hazard ratio, 3.59; 90% CI, 1.11 to 11.6) participants of CHS. Kaplan-Meier estimates of the 10-year cumulative incidence of stroke were greater among Val allele homozygotes than among Met allele carriers in both white (10% versus 6%) and black (12% versus 3%) participants of CHS. Conclusions The Val12Met SNP in ABCG2 (encoding a transporter of sterols and xenobiotics) was associated with incident ischemic stroke in white and black participants of CHS. PMID:19023099

  15. Cytoprotective roles of GSH, SOD and solcoseryl against ischemic damage and reperfusion injury to warm ischemic lung. Study of Canine warm ischemic lung.

    OpenAIRE

    Taniguchi, Hideki; Kawahara, Katsunobu; Nakasone, Tomonori; Ikari, Hideki; Honjoh, Seiji; Hisano, Hiroshi; Takahashi, Takao; Kusano, Hiroyuki; Ayabe, Hiroyoshi; Tomita, Masao

    1990-01-01

    This study was performed to clarify the roles of reduced glutathion (GSH), superoxide dismutase (SOD), and solcosaryl in ischemic damage and reperfusion injury to the warm ischemic lungs of experimental animals. Fifty-one warm ischemic canine lungs were made by hilar stripping and clamping of the left PA, PV and bronchus for 2-3 hours. In the Non-perfusion group, GSH (50mg/ kg, I. V.: Group II) and solcoseryl (50mg/kg, I. V.: Group III) were administered. In the perfusion group, Euro-Collins ...

  16. Metabolically healthy obesity and ischemic heart disease

    DEFF Research Database (Denmark)

    Hansen, Louise; Netterstrøm, Marie K.; Johansen, Nanna B.

    2017-01-01

    Context: Recent studies have suggested that a subgroup of obese individuals is not at increased risk of obesity-related complications. This subgroup has been referred to as metabolically healthy obese. Objective: To investigate whether obesity is a risk factor for development of ischemic heart...... disease (IHD) irrespective of metabolic health. Design: In all, 6238 men and women from the Danish prospective Inter99 study were followed during 10.6 (standard deviation = 1.7) years. Setting: General community. Participants: Participants were classified according to body mass index and four metabolic...

  17. Ischemic cardiac complications following G-CSF.

    Science.gov (United States)

    Eckman, Peter M; Bertog, Stefan C; Wilson, Robert F; Henry, Timothy D

    2010-07-01

    Granulocyte-colony stimulating factor (G-CSF) is commonly used in bone marrow transplant donors to increase the number of circulating progenitor cells. G-CSF has also been studied following myocardial infarction, but concern has been raised about the risks of G-CSF administration in patients with coronary artery disease. We present two cases of ischemic cardiac complications that are likely to be related to administration of G-CSF and provide a contemporary overview of the literature on the cardiovascular risks of G-CSF.

  18. Cardiogenic embolism producing crescendo transient ischemic attacks.

    Science.gov (United States)

    Geraghty, Patrick J; Oak, Jack; Choi, Eric T

    2005-09-01

    Lateralizing, repetitive transient ischemic attacks are characteristic of symptomatic carotid bifurcation atherosclerotic plaques. We report a case in which a cardiogenic embolus, after lodging at the left carotid bifurcation, produced crescendo episodes of expressive aphasia and mild right upper extremity weakness. Complete neurological recovery was achieved following emergent carotid embolectomy and endarterectomy. This case demonstrates that the laminar nature of internal carotid blood flow may result in the localization of embolic events to a single region of the cerebral vasculature, regardless of the source lesion in the carotid artery. The role of endoluminal techniques in the diagnosis and management of such lesions is discussed.

  19. Takayasu Arteritis Presenting with Ischemic Stroke: Two case reports

    Directory of Open Access Journals (Sweden)

    Fergane Memmodova

    2017-04-01

    Full Text Available Takayasu arteritis is a rare vasculitic disease characterized with inflamation of vessels. It commonly results stenosis and dilatations of aort and aortic branches. Ischemic Cerebrovascular Disease is one of the major complications of Takayasu arteritis. In this report we concluded two Takayasu arteritis cases in the light of current data whom presented with ischemic stroke clinical symptoms.

  20. Perceived stress and risk of ischemic heart disease

    DEFF Research Database (Denmark)

    Nielsen, Naja Rod; Kristensen, Tage Søndergård; Prescott, Eva

    2006-01-01

    It is unclear whether the commonly recognized link between stress and cardiovascular disease is causal or the result of reporting bias. The objective of this study was to address the association between perceived stress and first incidence of ischemic heart disease and to evaluate the suggested...... reporting bias by addressing subdiagnoses of ischemic heart disease separately....

  1. Multiple Silent Lacunes Are Associated with Recurrent Ischemic Stroke

    DEFF Research Database (Denmark)

    Andersen, Søren Due; Skjøth, Flemming; Yavarian, Yousef

    2016-01-01

    .16 (0.61-2.22) and 1.51 (0.86-2.66) for cardiovascular events. Conclusions: In this large cohort of patients with incident ischemic stroke and no AF, an increasing number of silent lacunes was associated with increasing incidence rates of ischemic stroke recurrence. In the adjusted Cox proportional...

  2. Complications of hemorrhagic and ischemic stroke : a CT perfusion evaluation

    NARCIS (Netherlands)

    Dankbaar, J.W.

    2010-01-01

    In this thesis the use of CT-perfusion (CTP) imaging in the evaluation of the most severe complications of subarachnoid hemorrhage (SAH)) and ischemic stroke was explored. These complications are delayed cerebral ischemia (DCI) after SAH and damage to the blood-brain barrier (BBB) after ischemic str

  3. Intra‐arterial treatment for acute ischemic stroke

    NARCIS (Netherlands)

    Berkhemer, O.A.

    2016-01-01

    This thesis deals with current issues in the field of acute ischemic stroke. The main objective has been to proof the effectiveness and safety of intra-arterial treatment in patients with acute ischemic stroke. MR CLEAN was the first study to proof the safety and effectiveness of intra-arterial

  4. Plasma biomarkers in the diagnosis of acute ischemic stroke.

    Science.gov (United States)

    Kim, Myeong Hee; Kang, So Young; Kim, Myung Chun; Lee, Woo In

    2010-01-01

    Rapid diagnosis and timely treatment improves the outcome in patients with ischemic stroke, but a rapid and sensitive blood test for ischemic stroke does not exist. This study tested whether a panel of biomarkers might be useful in the diagnosis of acute ischemic stroke. Consecutive patients with suspected stroke presenting to the emergency department of a university hospital in Korea were enrolled. Plasma specimens were assayed for brain natriuretic peptide, D-dimer, matrix metalloproteinase-9, S100β, and a proprietary composite multimarker index (MMX). There were 139 patients in this study, 89 of whom were diagnosed with acute ischemic stroke, 11 with acute cerebral hemorrhage, and 39 with other brain disorders. The MMX value was significantly higher in the patients with acute ischemic stroke in comparison to 57 healthy controls (p acute ischemic stroke vs those with acute cerebral hemorrhage (p = 0.884). The discriminatory capacity of MMX was modest, with an area under the receiver-operating-characteristic curve of 0.714 for acute stroke. Ischemic stroke was not diagnosed by any of the biochemical markers individually. Although the data suggest that MMX may be helpful to diagnose an acute stroke, it does not discriminate between acute ischemic stroke and acute hemorrhagic stroke.

  5. Inflammatory mechanisms in ischemic stroke: role of inflammatory cells

    Science.gov (United States)

    Jin, Rong; Yang, Guojun; Li, Guohong

    2010-01-01

    Inflammation plays an important role in the pathogenesis of ischemic stroke and other forms of ischemic brain injury. Experimentally and clinically, the brain responds to ischemic injury with an acute and prolonged inflammatory process, characterized by rapid activation of resident cells (mainly microglia), production of proinflammatory mediators, and infiltration of various types of inflammatory cells (including neutrophils, different subtypes of T cells, monocyte/macrophages, and other cells) into the ischemic brain tissue. These cellular events collaboratively contribute to ischemic brain injury. Despite intense investigation, there are still numerous controversies concerning the time course of the recruitment of inflammatory cells in the brain and their pathogenic roles in ischemic brain injury. In this review, we provide an overview of the time-dependent recruitment of different inflammatory cells following focal cerebral I/R. We discuss how these cells contribute to ischemic brain injury and highlight certain recent findings and currently unanswered questions about inflammatory cells in the pathophysiology of ischemic stroke. PMID:20130219

  6. Nonfasting glucose, ischemic heart disease, and myocardial infarction

    DEFF Research Database (Denmark)

    Benn, Marianne; Tybjaerg-Hansen, Anne; McCarthy, Mark I

    2012-01-01

    The purpose of this study was to test whether elevated nonfasting glucose levels associate with and cause ischemic heart disease (IHD) and myocardial infarction (MI).......The purpose of this study was to test whether elevated nonfasting glucose levels associate with and cause ischemic heart disease (IHD) and myocardial infarction (MI)....

  7. Sonographic and Endoscopic Findings in Cocaine-Induced Ischemic Colitis

    DEFF Research Database (Denmark)

    Leth, Thomas; Wilkens, Rune; Bonderup, Ole Kristian

    2015-01-01

    Cocaine-induced ischemic colitis is a recognized entity. The diagnosis is based on clinical and endoscopic findings. However, diagnostic imaging is helpful in the evaluation of abdominal symptoms and prior studies have suggested specific sonographic findings in ischemic colitis. We report...

  8. Selective neuronal loss in ischemic stroke and cerebrovascular disease

    Science.gov (United States)

    Baron, Jean-Claude; Yamauchi, Hiroshi; Fujioka, Masayuki; Endres, Matthias

    2014-01-01

    As a sequel of brain ischemia, selective neuronal loss (SNL)—as opposed to pannecrosis (i.e. infarction)—is attracting growing interest, particularly because it is now detectable in vivo. In acute stroke, SNL may affect the salvaged penumbra and hamper functional recovery following reperfusion. Rodent occlusion models can generate SNL predominantly in the striatum or cortex, showing that it can affect behavior for weeks despite normal magnetic resonance imaging. In humans, SNL in the salvaged penumbra has been documented in vivo mainly using positron emission tomography and 11C-flumazenil, a neuronal tracer validated against immunohistochemistry in rodent stroke models. Cortical SNL has also been documented using this approach in chronic carotid disease in association with misery perfusion and behavioral deficits, suggesting that it can result from chronic or unstable hemodynamic compromise. Given these consequences, SNL may constitute a novel therapeutic target. Selective neuronal loss may also develop at sites remote from infarcts, representing secondary ‘exofocal' phenomena akin to degeneration, potentially related to poststroke behavioral or mood impairments again amenable to therapy. Further work should aim to better characterize the time course, behavioral consequences—including the impact on neurological recovery and contribution to vascular cognitive impairment—association with possible causal processes such as microglial activation, and preventability of SNL. PMID:24192635

  9. Dynamic changes in DNA methylation in ischemic tolerance

    Directory of Open Access Journals (Sweden)

    Robert eMeller

    2015-05-01

    Full Text Available Epigenetic mediators of gene expression are hypothesized to regulate transcriptomic responses to preconditioning ischemia and ischemic tolerance. Here we utilized a methyl-DNA enrichment protocol and sequencing (ChIP-seq to identify patterns of DNA methylation in an established model of ischemic tolerance in neuronal cultures (oxygen and glucose deprivation: OGD. We observed an overall decrease in global DNA methylation at 4h following preconditioning ischemia (30min OGD, harmful ischemia (120min OGD and in ischemic tolerant neuronal cultures (30min OGD, 24h recovery, 120min OGD. We detected a smaller cohort of hypermethylated regions following ischemic conditions, which were further analyzed revealing differential chromosomal localization of methylation, and a differential concentration of methylation on genomic regions. Together these data show that the temporal profiles of DNA methylation with respect to chromatin hyper – and hypo-methylation following various ischemic conditions, are highly dynamic and may reveal novel targets for neuroprotection.

  10. Genetics of Atrial Fibrillation and Possible Implications for Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Robin Lemmens

    2011-01-01

    Full Text Available Atrial fibrillation is the most common cardiac arrhythmia mainly caused by valvular, ischemic, hypertensive, and myopathic heart disease. Atrial fibrillation can occur in families suggesting a genetic background especially in younger subjects. Additionally recent studies have identified common genetic variants to be associated with atrial fibrillation in the general population. This cardiac arrhythmia has important public health implications because of its main complications: congestive heart failure and ischemic stroke. Since atrial fibrillation can result in ischemic stroke, one might assume that genetic determinants of this cardiac arrhythmia are also implicated in cerebrovascular disease. Ischemic stroke is a multifactorial, complex disease where multiple environmental and genetic factors interact. Whether genetic variants associated with a risk factor for ischemic stroke also increase the risk of a particular vascular endpoint still needs to be confirmed in many cases. Here we review the current knowledge on the genetic background of atrial fibrillation and the consequences for cerebrovascular disease.

  11. Ischemic stroke susceptibility gene in a Northern Han Chinese population

    Institute of Scientific and Technical Information of China (English)

    Haiping Wang; Shujuan Shi; Wenjing Yan; Yan Song; Jingjing Zhan; Chen Zhang; Haiji Wang

    2013-01-01

    Interleukin-18 gene promoter polymorphisms are potential risk factors for ischemic cerebrovascular disease, and the-607C al ele may increase ischemic stroke risk in the Han Chinese population. In the present study, we recruited 291 patients with ischemic cerebrovascular disease from the Affi-liated Hospital of Qingdao University Medical Col ege, China, and 226 healthy controls. Both pa-tients and controls were from the Han population in northern China. Immunoresonance scattering assays detected increased serum amyloid A protein, C-reactive protein, and interleukin-18 levels in ischemic cerebrovascular disease patients compared with healthy controls. Analysis of the-607C/A (rs1946518) polymorphism in the interleukin-18 gene promoter showed ischemic cerebrovascular disease patients exhibited increased frequencies of the CC genotype and C al eles than healthy controls. Genotype and al ele frequencies of the interleukin-18-137G/C (rs187238) polymorphism and the-13T/C (rs11024595) polymorphism in the 5'-flanking region of serum amyloid A, showed no significant difference between the two groups. Multivariate logistic regression analysis on the interleukin-18 promoter A/C genetic locus, for correction of age, gender, history of smoking, hyper-tension, diabetes mel itus, hypercholesteremia, and an ischemic stroke family history, showed ischemic cerebrovascular disease risk in individuals without the A al ele (C homozygotes) was 2.2-fold greater than in A al ele carriers. Overal , our findings suggest that the-13T/C (rs11024595) polymorphism in the 5′-flanking region of serum amyloid A has no correlation with ischemic cere-brovascular disease, but the C al ele of the-607C/A (rs1946518) polymorphism in the interleukin-18 promoter is a high-risk factor for ischemic cerebrovascular disease in the Han population of northern China. In addition, the A al ele is likely a protective gene for ischemic cerebrovascular disease.

  12. Biomarkers of Hypoxic Ischemic Encephalopathy in Newborns

    Directory of Open Access Journals (Sweden)

    Martha V. Douglas-Escobar

    2012-11-01

    Full Text Available As neonatal intensive care has evolved, the focus has shifted from improving mortality alone to an effort to improve both mortality and morbidity. The most frequent source of neonatal brain injury occurs as a result of hypoxic-ischemic injury. Hypoxic-ischemic injury occurs in about 2 of 1,000 full-term infants and severe injured infants will have lifetime disabilities and neurodevelopmental delays. Most recently, remarkable efforts toward neuroprotection have been started with the advent of therapeutic hypothermia and a key step in the evolution of neonatal neuroprotection is the discovery of biomarkers that enable the clinician-scientist to screen infants for brain injury, monitor progression of disease, identify injured brain regions, and assess efficacy of neuroprotective clinical trials. Lastly, biomarkers offer great hope identifying when an injury occurred shedding light on the potential pathophysiology and the most effective therapy. In this article, we will review biomarkers of HIE including S100b, neuron specific enolase, umbilical cord IL-6, CK-BB, GFAP, myelin basic protein, UCHL-1, and pNF-H. We hope to contribute to the awareness, validation and clinical use of established as well as novel neonatal brain injury biomarkers.

  13. Green space and mortality following ischemic stroke.

    Science.gov (United States)

    Wilker, Elissa H; Wu, Chih-Da; McNeely, Eileen; Mostofsky, Elizabeth; Spengler, John; Wellenius, Gregory A; Mittleman, Murray A

    2014-08-01

    Residential proximity to green space has been associated with physical and mental health benefits, but whether green space is associated with post-stroke survival has not been studied. Patients ≥ 21 years of age admitted to the Beth Israel Deaconess Medical Center (BIDMC) between 1999 and 2008 with acute ischemic stroke were identified. Demographics, presenting symptoms, medical history and imaging results were abstracted from medical records at the time of hospitalization for stroke onset. Addresses were linked to average Normalized Difference Vegetation Index, distance to roadways with more than 10,000 cars/day, and US census block group. Deaths were identified through June 2012 using the Social Security Death Index. There were 929 deaths among 1645 patients with complete data (median follow up: 5 years). In multivariable Cox models adjusted for indicators of medical history, demographic and socioeconomic factors, the hazard ratio for patients living in locations in the highest quartile of green space compared to the lowest quartile was 0.78 (95% Confidence Interval: 0.63-0.97) (p-trend = 0.009). This association remained statistically significant after adjustment for residential proximity to a high traffic road. Residential proximity to green space is associated with higher survival rates after ischemic stroke in multivariable adjusted models. Further work is necessary to elucidate the underlying mechanisms for this association, and to better understand the exposure-response relationships and susceptibility factors that may contribute to higher mortality in low green space areas. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Mesenchymal stromal cell therapy in ischemic stroke

    Directory of Open Access Journals (Sweden)

    Zhang Y

    2016-11-01

    Full Text Available Ye Zhang, Hong Deng, Chao Pan, Yang Hu, Qian Wu, Na Liu, Zhouping Tang Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People’s Republic of China Abstract: Stroke is a clinical disease with high incidence, high disability rate, and high mortality. But effective and safe therapy for stroke remains limited. Adult mesenchymal stromal cells (MSCs perform a variety of therapeutic functions. MSC delivery improves neurological outcomes in ischemic stroke models via neurorestorative and neuroprotective effects such as angiogenic effects, promoting endogenous proliferation, and reducing apoptosis and inflammation. MSC secretome also showed powerful therapeutic effects as a cell-based therapy in animal experiments. Several clinical trials on MSC implantation via different routes have now been completed in patients with stroke. Although challenges such as immunogenicity of allo-MSCs and large-scale production strategies need to be overcome, MSCs can be considered as a promising potential therapy for ischemic stroke. Keywords: mesenchymal stromal cell, stroke, therapy, transplantation, exosomes

  15. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  16. Evolving Treatments for Acute Ischemic Stroke.

    Science.gov (United States)

    Zerna, Charlotte; Hegedus, Janka; Hill, Michael D

    2016-04-29

    The purpose of this article is to review advances in stroke treatment in the hyperacute period. With recent evolutions of technology in the fields of imaging, thrombectomy devices, and emergency room workflow management, as well as improvement in statistical methods and study design, there have been ground breaking changes in the treatment of acute ischemic stroke. We describe how stroke presents as a clinical syndrome and how imaging as the most important biomarker will help differentiate between stroke subtypes and treatment eligibility. The evolution of hyperacute treatment has led to the current standard of care: intravenous thrombolysis with tissue-type plasminogen activator and endovascular treatment for proximal vessel occlusion in the anterior cerebral circulation. All patients with acute ischemic stroke are in need of hyperacute secondary prevention because the risk of recurrence is highest closest to the index event. The dominant themes of modern stroke care are the use of neurovascular imaging and speed of diagnosis and treatment. © 2016 American Heart Association, Inc.

  17. Complement in the Homeostatic and Ischemic Brain

    Science.gov (United States)

    Alawieh, Ali; Elvington, Andrew; Tomlinson, Stephen

    2015-01-01

    The complement system is a component of the immune system involved in both recognition and response to pathogens, and it is implicated in an increasing number of homeostatic and disease processes. It is well documented that reperfusion of ischemic tissue results in complement activation and an inflammatory response that causes post-reperfusion injury. This occurs following cerebral ischemia and reperfusion and triggers secondary damage that extends beyond the initial infarcted area, an outcome that has rationalized the use of complement inhibitors as candidate therapeutics after stroke. In the central nervous system, however, recent studies have revealed that complement also has essential roles in synaptic pruning, neurogenesis, and neuronal migration. In the context of recovery after stroke, these apparent divergent functions of complement may account for findings that the protective effect of complement inhibition in the acute phase after stroke is not always maintained in the subacute and chronic phases. The development of effective stroke therapies based on modulation of the complement system will require a detailed understanding of complement-dependent processes in both early neurodegenerative events and delayed neuro-reparatory processes. Here, we review the role of complement in normal brain physiology, the events initiating complement activation after cerebral ischemia-reperfusion injury, and the contribution of complement to both injury and recovery. We also discuss how the design of future experiments may better characterize the dual role of complement in recovery after ischemic stroke. PMID:26322048

  18. Genistein: A Boon for Mitigating Ischemic Stroke.

    Science.gov (United States)

    Nabavi, Seyed Fazel; Daglia, Maria; Tundis, Rosa; Loizzo, Monica Rosa; Sobarzo-Sanchez, Eduardo; Orhan, Ilkay Erdogan; Nabavi, Seyed Mohammad

    2015-01-01

    In last decades, diet and dietary components have been regarded as important strategies to prevent the development or mitigate numerous chronic diseases, including inflammation, cardiovascular pathologies, cancer, etc. One of the most common dietary components of Asian population is soy. A plethora of research shows the promising effect of soy soy-based foodstuffs and genistein, which is one of the predominant isoflavone compounds, in the prevention and mitigation of stroke. Growing evidence shows that genistein, which is a selective estrogen receptor modulator, mitigates ischemic stroke-induced damages through the modification of oxidative stress and molecular pathways. The promising pharmacological role of genistein is attributed to its ability to suppress nuclear factor (NF)-kappa B and Akt signaling pathway, direct antioxidant action, and targeting estrogen and androgen-mediated molecular pathways which help to mitigate stroke damages and prolong cell survival. In this work, we systematically review the current reports on the therapeutic role of genistein against ischemic stroke and its molecular mechanism of actions.

  19. Prevalence of electrocardiographic ST-T changes during acute ischemic stroke in patients without known ischemic heart disease

    DEFF Research Database (Denmark)

    Jensen, Jesper K; Bak, Søren; Flemming Høilund-Carlsen, Poul;

    2008-01-01

    We evaluated characteristics and prevalence of ST-segment depression and/or T-wave inversion in the resting electrocardiogram of 244 consecutive patients with acute ischemic stroke, but without ischemic heart disease. The prevalence of ST-T changes ranged from 13% to 16% and this is what to expect...

  20. Diagnosing Paroxysmal Atrial Fibrillation in Patients With Ischemic Strokes and Transient Ischemic Attacks Using Echocardiographic Measurements of Left Atrium Function

    DEFF Research Database (Denmark)

    Skaarup, Kristoffer Grundtvig; Christensen, Hanne; Høst, Nis;

    2016-01-01

    AF in patients with ischemic stroke (IS) and transient ischemic attack (TIA). We retrospectively analyzed 219 patients who after acute IS or TIA underwent a transthoracic echocardiographic examination. Patients were designated as patients with paroxysmal AF if they had one or more reported incidents...

  1. Lifestyle And Effective Factors On It Among Patients With Transient Ischemic Attack

    Directory of Open Access Journals (Sweden)

    Tahere Sarboozi Hosein

    2017-02-01

    Full Text Available Background Choosing wrong type of lifestyle by a person can predispose him/her to cardiovascular disease such as strokes, which can be a serious hazard for his/her health. Transient ischemic attack is a transient attack of impaired brain function disorder that can predict further strokes. Therefore, this study has done by the purpose of defining lifestyle condition about the patients with transient ischemic attack. Material and methods This study is the analytic-descriptive type and has been conducted on 60 patients with transient ischemic attack that admitted to the chosen hospital of Tehran, by random sampling method in 1394.  The research tools were patient condition demographic questionnaire and health promotion lifestyle profile (HPLP ll. The collected data were analyzed by the SPSS 16 software and statistical tests. Findings and results Lifestyle of 63.25% of patients estimated at medium level. Physical activity, stress management and health responsibility dimensions also had lower score in comparison with other dimensions. Interpersonal relationships dimension had the highest score. Statistically significant relation has seen among the lifestyle and education level and economic situation (P<0.05 Conclusion Improvement and promotion of patient’s lifestyle, especially from the point of physical activity and stress management, requires more attention and by considering the fact that the main cause of stroke is related to person’s lifestyle, the necessity of training programs implementation, in order to change or preserve these patients’ lifestyle, is recommended.

  2. The taxonomy statistic uncovers novel clinical patterns in a population of ischemic stroke patients.

    Directory of Open Access Journals (Sweden)

    Andrzej Tukiendorf

    Full Text Available In this paper, we describe a simple taxonomic approach for clinical data mining elaborated by Marczewski and Steinhaus (M-S, whose performance equals the advanced statistical methodology known as the expectation-maximization (E-M algorithm. We tested these two methods on a cohort of ischemic stroke patients. The comparison of both methods revealed strong agreement. Direct agreement between M-S and E-M classifications reached 83%, while Cohen's coefficient of agreement was κ = 0.766(P < 0.0001. The statistical analysis conducted and the outcomes obtained in this paper revealed novel clinical patterns in ischemic stroke patients. The aim of the study was to evaluate the clinical usefulness of Marczewski-Steinhaus' taxonomic approach as a tool for the detection of novel patterns of data in ischemic stroke patients and the prediction of disease outcome. In terms of the identification of fairly frequent types of stroke patients using their age, National Institutes of Health Stroke Scale (NIHSS, and diabetes mellitus (DM status, when dealing with rough characteristics of patients, four particular types of patients are recognized, which cannot be identified by means of routine clinical methods. Following the obtained taxonomical outcomes, the strong correlation between the health status at moment of admission to emergency department (ED and the subsequent recovery of patients is established. Moreover, popularization and simplification of the ideas of advanced mathematicians may provide an unconventional explorative platform for clinical problems.

  3. Accuracy of Dobutamine Stress Echocardiography in Detecting Recovery of Contractile Reserve after Revascularization of Ischemic Myocardium

    Directory of Open Access Journals (Sweden)

    Abas Ali karimi

    2007-09-01

    Full Text Available Background: This study was designed to investigate the accuracy of dobutamine stress echocardiography (DSE in detecting the post-revascularization recovery rate of contractile reserve (CR in ischemic myocardium. Methods: A total of 112 segments from seven patients with low ejection fraction (<35% and coronary artery disease were evaluated with DSE one week before and 12 weeks after coronary artery bypass graft surgery (CABG. Sensitivity, specificity, and positive and negative predictive values of DSE for detecting the recovery rate of CR were calculated based upon their standard definition and were presented with 95% confidence intervals (CI. Results: The mean baseline left ventricular ejection fraction was 31±4%, which reached 35±7% after CABG unremarkably. The recovery rates of resting function and CR were 18.2% and 50% for hypokinetic and 15.6% and 24.1 for akinetic segments respectively. Specificity, sensitivity, and positive and negative predictive values of DSE for detecting the recovery of CR were 83% (CI=69-97, 89% (CI=83-96, 94% (CI = 88-99, and 73 % (CI = 55-88, respectively. Conclusion: Despite acceptable sensitivity, specificity, and positive predictive value, DSE has a relatively lower negative predictive value for detecting the recovery of CR in ischemic myocardium and, consequently, the full extent of myocardial viability. Further sensitive techniques may, therefore, be needed to provide complementary information regarding long-term functional outcome.

  4. Effects of ischemic preconditioning on cyclinD1 expression during early ischemic reperfusion in rats

    Institute of Scientific and Technical Information of China (English)

    Fang-Gang Cai; Jian-Sheng Xiao; Qi-Fa Ye

    2006-01-01

    AIM: To observe the effect of ischemic preconditioning on cyclinD1 expression in rat liver cells during early ischemic reperfusion.METHODS: Fifty-four SD rats were randomly divided into ischemic preconditioning group (IP), ischemia/reperfusion group (IR) and sham operation group (SO). The IP and IR groups were further divided into four sub-groups (n = 6). Sham operation group (SO)served as the control group (n = 6). A model of partial liver ischemia/reperfusion was used, in which rats were subjected to l