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https://www.readbyqxmd.com/read/29052571/susceptibility-weighted-imaging-in-thrombolytic-therapy-of-acute-ischemic-stroke
#1
REVIEW
Lin Li, Ming-Su Liu, Guang-Qin Li, Yang Zheng, Tong-Li Guo, Xin Kang, Mao-Ting Yuan
OBJECTIVE: To provide a comprehensive and latest overview of susceptibility-weighted imaging (SWI) in the application of thrombolysis in acute ischemic stroke, and to update the decision-making effect and clinical value of SWI on identifying stroke patients suitable for thrombolytic therapy and possible benefits and risks followed. DATA SOURCES: Literatures referred to this review were collected from PubMed, Medline, and EMBASE published till May 2017, using the search terms including susceptibility-weighted imaging, gradient-echo, T2*, thrombolysis, recombinant tissue plasminogen activator (rt-PA), thrombolytic therapy, and stroke...
October 20, 2017: Chinese Medical Journal
https://www.readbyqxmd.com/read/29037436/which-imaging-before-reperfusion-strategy
#2
REVIEW
J M Olivot
The ischemic penumbra is a transient and potentially reversible condition. Therefore, infarct progression and its counterpart penumbral salvage are highly variable and result from the interaction of 3 major factors: collateral flow, revascularization delay and success. Multimodal brain imaging now offers in clinical practice an exhaustive characterization of the acute ischemic injury: vessel site occlusion, infarction/critical hypoperfusion volume, and collateral flow. From 1995 to 2015, IV alteplase administered within 4...
October 13, 2017: Revue Neurologique
https://www.readbyqxmd.com/read/29034608/nanoparticle-based-therapeutics-for-brain-injury
#3
REVIEW
Vimala N Bharadwaj, Duong T Nguyen, Vikram D Kodibagkar, Sarah E Stabenfeldt
Brain injuries affect a large patient population with major physical and emotional suffering for patients and their relatives; at a significant cost to the society. Effective diagnostic and therapeutic options available for brain injuries are limited by the complex brain injury pathology involving blood-brain barrier (BBB). Brain injuries, including ischemic stroke and brain trauma, initiate BBB opening for a short period of time, which is followed by a second reopening for an extended time. The leaky BBB and/or the alterations in the receptor expression on BBB may provide opportunities for therapeutic delivery via nanoparticles (NPs)...
October 16, 2017: Advanced Healthcare Materials
https://www.readbyqxmd.com/read/29018134/neuronal-sirt1-silent-information-regulator-2-homologue-1-regulates-glycolysis-and-mediates-resveratrol-induced-ischemic-tolerance
#4
Kevin B Koronowski, Nathalie Khoury, Isabel Saul, Zachary B Loris, Charles H Cohan, Holly M Stradecki-Cohan, Kunjan R Dave, Juan I Young, Miguel A Perez-Pinzon
BACKGROUND AND PURPOSE: Resveratrol, at least in part via SIRT1 (silent information regulator 2 homologue 1) activation, protects against cerebral ischemia when administered 2 days before injury. However, it remains unclear if SIRT1 activation must occur, and in which brain cell types, for the induction of neuroprotection. We hypothesized that neuronal SIRT1 is essential for resveratrol-induced ischemic tolerance and sought to characterize the metabolic pathways regulated by neuronal Sirt1 at the cellular level in the brain...
October 10, 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28992250/equivalency-of-the-quality-of-sublethal-lesions-after-photons-and-high-linear-energy-transfer-ion-beams
#5
Yoshiya Furusawa, Mizuho Nakano-Aoki, Yoshitaka Matsumoto, Ryoichi Hirayama, Alisa Kobayashi, Teruaki Konishi
The quality of the sublethal damage (SLD) after irradiation with high-linear energy transfer (LET) ion beams was investigated with low-LET photons. Chinese hamster V79 cells and human squamous carcinoma SAS cells were first exposed to a priming dose of different ion beams at different LETs at the Heavy Ion Medical Accelerator in the Chiba facility. The cells were kept at room temperature and then exposed to a secondary test dose of X-rays. Based on the repair kinetics study, the surviving fraction of cells quickly increased with the repair time, and reached a plateau in 2-3 h, even when cells had received priming monoenergetic high-LET beams or spread-out Bragg peak beams as well as X-ray irradiation...
July 11, 2017: Journal of Radiation Research
https://www.readbyqxmd.com/read/28987436/ischemic-stroke-advances-in-diagnosis-and-management
#6
REVIEW
Courtney R Cassella, Andy Jagoda
Acute ischemic stroke carries the risk of morbidity and mortality. Since the advent of intravenous thrombolysis, there have been improvements in stroke care and functional outcomes. Studies of populations once excluded from thrombolysis have begun to elucidate candidates who might benefit and thus should be engaged in the process of shared decision-making. Imaging is evolving to better target the ischemic penumbra salvageable with prompt reperfusion. Availability and use of computed tomography angiography identifies large-vessel occlusions, and new-generation endovascular therapy devices are improving outcomes in these patients...
November 2017: Emergency Medicine Clinics of North America
https://www.readbyqxmd.com/read/28987197/neuropathology-of-cerebrovascular-diseases
#7
Isidro Ferrer, Noemi Vidal
The chapter describes the epidemiology of cerebrovascular diseases, anatomy of the cerebral blood vessels, pathophysiology of ischemia, hypoxia, hypoxemia, anemic hypoxia, histotoxic hypoxia, carbon monoxide damage, hyperoxid brain damage and decompression sickness, and selective cell and regional vulnerability; diseases of the blood vessels including atherosclerosis, hypertensive angiopathy, small vessel disease, inflammatory vascular diseases, cerebral amyloid angiopathies, CADASIL, CARASIL and other diseases that can lead to cerebrovascular occlusion; intracranial and intraspinal aneurysms and vascular malformations; hematologic disorders that can cause cerebral infarct or hemorrhage; brain ischemic damage; and spontaneous intracranial bleeding...
2017: Handbook of Clinical Neurology
https://www.readbyqxmd.com/read/28984315/pet-imaging-of-the-neurovascular-interface-in-cerebrovascular-disease
#8
REVIEW
Nicholas R Evans, Jason M Tarkin, John R Buscombe, Hugh S Markus, James H F Rudd, Elizabeth A Warburton
Cerebrovascular disease encompasses a range of pathologies that affect different components of the cerebral vasculature and brain parenchyma. Large artery atherosclerosis, acute cerebral ischaemia, and intracerebral small vessel disease all demonstrate altered metabolic processes that are key to their pathogenesis. Although structural imaging techniques such as MRI are the mainstay of clinical care and research in cerebrovascular disease, they have limited ability to detect these pathophysiological processes in vivo...
October 6, 2017: Nature Reviews. Neurology
https://www.readbyqxmd.com/read/28983488/neurovascular-function-recovery-after-focal-ischemic-stroke-by-enhancing-cerebral-collateral-circulation-via-peripheral-stimulation-mediated-interarterial-anastomosis
#9
Han-Chi Pan, Lun-De Liao, Yu-Chun Lo, Jia-Wei Chen, Han-Lin Wang, Li Yang, Yao-Wen Liang, Po-Yu Huang, Ming-Hsun Yang, You-Yin Chen
Current treatments for ischemic stroke have focused on the administration of a tissue plasminogen activator, although the associated side effects and subsequent reperfusion injury remain challenging. Peripheral electrical stimulation has shed light on therapeutic interventions for ischemia by increasing cerebral blood flow (CBF) to the target region through collateral circulation, although the mechanism remains elusive. Here, a focal photothrombotic ischemic (PTI) stroke was induced in the right hemispheric primary somatosensory forelimb cortex (S1FL) of rat brains, and the therapeutic effects of forelimb and hindlimb stimulation were characterized at the contralesional S1FL...
July 2017: Neurophotonics
https://www.readbyqxmd.com/read/28982332/asymmetric-cerebrovascular-collateral-supply-affects-cognition-in-patients-with-unilateral-carotid-artery-stenosis
#10
Kuo-Lun Huang, Ting-Yu Chang, Chien-Hung Chang, Ho-Ling Liu, Yeu-Jhy Chang, Chi-Hung Liu, Ho-Fai Wong, Yi-Ming Wu, Tsong-Hai Lee, Meng-Yang Ho
BACKGROUND: The time to maximum of the residue function (TMax) has been employed to identify the penumbra in acute ischemic stroke. Cognitive impairment in patients with carotid artery stenosis (CAS) has been attributed to chronic cerebral hypoperfusion. The study aimed to examine whether cognitive impairment can be detected based on a preliminary TMax cutoff in patients with unilateral CAS. METHODS: Fifty unilateral CAS patients underwent dynamic susceptibility contrast MR perfusion...
October 5, 2017: Current Neurovascular Research
https://www.readbyqxmd.com/read/28982330/potential-biomarkers-with-plasma-cortisol-brain-derived-neurotrophic-factor-and-nitrites-in-patients-with-acute-ischemic-stroke
#11
S Casas, A F Perez, M Mattiazzi, J Lopez, A Folgueira, G M Gargiulo-Monachelli, M C Gonzalez Deniselle, A F De Nicola
BACKGROUND: Acute ischemic stroke (AIS) represents an economic challenge for health systems all over the globe. Changes of neuroactive steroids have been found in different neurological diseases. We have previously demonstrated that old patients with AIS show changes of plasma cortisol and estradiol concentrations, in that increased steroid levels are associated with a deterioration of neurological status and a worse cognitive decline. OBJECTIVE: The present study assessed in patients with AIS if changes of behavior, brain-derived neurotrophic factor (BDNF) and nitrites (NO-2) bear a relationship with the degree of hypercortisolism...
October 5, 2017: Current Neurovascular Research
https://www.readbyqxmd.com/read/28975637/technical-note-dosimetric-characteristics-of-the-ocular-beam-line-and-commissioning-data-for-an-ocular-proton-therapy-planning-system-at-the-proton-therapy-center-houston
#12
Uwe Titt, Kazumichi Suzuki, Yupeng Li, Narayan Sahoo, Michael T Gillin, Xiaorong R Zhu
PURPOSE: To systematically analyze and present the properties of a small-field, double-scattering proton beam line intended to be used for the treatment of ocular cancer, and to provide configuration data for commission of the Eclipse Ocular Proton Planning System. METHODS: Measurements were made using ionization chambers, diodes, and films to determine dose profiles and output factors of the proton beams of the beam line at the Proton Therapy Center Houston. In parallel, Monte Carlo simulations were performed to validate the measured data and to provide additional insight into detailed beam parameters that are hard to measure, such as field size factors and a comparison of output factors as a function of circular and rectangular fields...
October 4, 2017: Medical Physics
https://www.readbyqxmd.com/read/28974996/monitoring-pressure-augmentation-in-patients-with-ischemic-penumbra-using-continuous-electroencephalogram-three-cases-and-a-review-of-the-literature
#13
Christopher R Newey, Vikas Gupta, Agnieszka A Ardelt
BACKGROUND: Continuous electroencephalography (CEEG) is a sensitive, noninvasive surrogate monitor of cerebral blood flow (CBF). Changes in CBF can be seen as changes in the frequencies on the CEEG. This case series suggests that increase in CEEG frequencies may be used to detect improved CBF following pressure augmentation such as with treatment of vasospasm from subarachnoid hemorrhage (SAH) or acute thrombosis from ischemic stroke. The application of this observation to clinical decision-making has not been clearly defined and requires further study...
October 2017: Neurohospitalist
https://www.readbyqxmd.com/read/28965105/incorporation-of-relative-cerebral-blood-flow-into-ct-perfusion-maps-reduces-false-at-risk-penumbra
#14
Shlomi Peretz, David Orion, David Last, Yael Mardor, Yotam Kimmel, Shelly Yehezkely, Eyal Lotan, Ze'ev Itsekson-Hayosh, Sylvia Koton, David Guez, David Tanne
PURPOSE: The region defined as 'at risk' penumbra by current CT perfusion (CTP) maps is largely overestimated. We aimed to quantitate the portion of true 'at risk' tissue within CTP penumbra and to determine the parameter and threshold that would optimally distinguish it from false 'at risk' tissue, that is, benign oligaemia. METHODS: Among acute stroke patients evaluated by multimodal CT (NCCT/CTA/CTP) we identified those that had not undergone endovascular/thrombolytic treatment and had follow-up NCCT...
September 30, 2017: Journal of Neurointerventional Surgery
https://www.readbyqxmd.com/read/28963051/-phenserine-inhibits-neuronal-apoptosis-following-ischemia-reperfusion-injury
#15
Cheng-Fu Chang, Jing-Huei Lai, John Chung-Che Wu, Nigel H Greig, Robert E Becker, Yu Luo, Yen-Hua Chen, Shuo-Jhen Kang, Yung-Hsiao Chiang, Kai-Yun Chen
Stroke commonly leads to adult disability and death worldwide. Its major symptoms are spastic hemiplegia and discordant motion, consequent to neuronal cell death induced by brain vessel occlusion. Acetylcholinesterase (AChE) is upregulated and allied with inflammation and apoptosis after stroke. Recent studies suggest that AChE inhibition ameliorates ischemia-reperfusion injury and has neuroprotective properties. (-)-Phenserine, a reversible AChE inhibitor, has a broad range of actions independent of its AChE properties, including neuroprotective ones...
September 26, 2017: Brain Research
https://www.readbyqxmd.com/read/28959484/determinants-of-the-impact-of-blood-pressure-variability-on-neurological-outcome-after-acute-ischaemic-stroke
#16
Adam de Havenon, Alicia Bennett, Gregory J Stoddard, Gordon Smith, Lee Chung, Steve O'Donnell, J Scott McNally, David Tirschwell, Jennifer J Majersik
INTRODUCTION: Increased blood pressure variability (BPV) is detrimental after acute ischaemic stroke, but the interaction between BPV and neuroimaging factors that directly influence stroke outcome has not been explored. METHODS: We retrospectively reviewed inpatients from 2007 to 2014 with acute anterior circulation ischaemic stroke, CT perfusion and angiography at hospital admission, and a modified Rankin Scale (mRS) 30-365 days after stroke onset. BPV indices included SD, coefficient of variation and successive variation of the systolic blood pressure between 0 and 120 hours after admission...
March 2017: Stroke and Vascular Neurology
https://www.readbyqxmd.com/read/28948399/interventional-magnetic-resonance-imaging-guided-carotid-embolectomy-using-a-novel-resonant-marker-catheter-demonstration-of-preclinical-feasibility
#17
Jeffrey K Yang, Andre M Cote, Caroline D Jordan, Sravani Kondapavulur, Aaron D Losey, David McCoy, Andrew Chu, Jay F Yu, Teri Moore, Carol Stillson, Fabio Settecase, Matthew D Alexander, Andrew Nicholson, Daniel L Cooke, Maythem Saeed, Dave Barry, Alastair J Martin, Mark W Wilson, Steven W Hetts
To assess the visualization and efficacy of a wireless resonant circuit (wRC) catheter system for carotid artery occlusion and embolectomy under real-time MRI guidance in vivo, and to compare MR imaging modality with x-ray for analysis of qualitative physiological measures of blood flow at baseline and after embolectomy. The wRC catheter system was constructed using a MR compatible PEEK fiber braided catheter (Penumbra, Inc, Alameda, CA) with a single insulated longitudinal copper loop soldered to a printed circuit board embedded within the catheter wall...
September 25, 2017: Biomedical Microdevices
https://www.readbyqxmd.com/read/28946180/usefulness-of-contralateral-carotid-angiography-in-revascularization-therapy-of-acute-internal-carotid-artery-occlusion
#18
Kiyoshi Tsuji, Nobuhiro Nakagawa, Norihito Fukawa, Masaharu Miyauchi, Kentaro Furukawa, Kinya Nakanishi, Naoki Nakano, Kazuo Kataoka, Amami Kato
OBJECTIVE The vascular lumen of an acutely occluded internal carotid artery (ICA) generally contains numerous thrombi. Therefore, carotid angiography on the affected side during revascularization therapy of acute ICA occlusion has a potential risk of causing distal embolization. In this study the authors propose the use of contralateral carotid angiography. METHODS Six patients with acute ICA occlusion underwent revascularization therapy using a stent retriever or Penumbra system. Revascularization therapy was performed with placement of a 9-Fr balloon-guiding catheter (BGC) in the affected ICA and a 4-Fr diagnostic catheter in the contralateral ICA...
September 15, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/28941738/spreading-depolarization-is-not-an-epiphenomenon-but-the-principal-mechanism-of-the-cytotoxic-edema-in-various-gray-matter-structures-of-the-brain-during-stroke
#19
REVIEW
Jens P Dreier, Coline L Lemale, Vasilis Kola, Alon Friedman, Karl Schoknecht
Spreading depolarization (SD) is a phenomenon of various cerebral gray matter structures that only occurs under pathological conditions. In the present paper, we summarize the evidence from several decades of research that SD and cytotoxic edema in these structures are largely overlapping terms. SD/cytotoxic edema is a toxic state that - albeit initially reversible - leads eventually to cellular death when it is persistent. Both hemorrhagic and ischemic stroke are among the most prominent causes of SD/cytotoxic edema...
September 21, 2017: Neuropharmacology
https://www.readbyqxmd.com/read/28941516/continuous-aspiration-mechanical-thrombectomy-for-the-management-of-submassive-pulmonary-embolism-a-single-center-experience
#20
Ramsey Al-Hakim, Alok Bhatt, James F Benenati
The Indigo Mechanical Thrombectomy System (Penumbra, Inc, Alameda, California) was used to treat 6 patients with submassive pulmonary embolism (PE) and a contraindication to thrombolysis. Systolic pulmonary artery pressure (58.2 mm Hg vs 43.0 mm Hg, P < .05), right ventricular/left ventricular ratio (1.7 vs 1.1, P < .05), Miller index (15.0 vs 9.8, P < 0.01), and CT obstructive index (60.4% vs 47.0%, P < .01) were significantly reduced after mechanical thrombectomy. There were no procedural or periprocedural complications...
October 2017: Journal of Vascular and Interventional Radiology: JVIR
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