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Active clinical trials for "Stroke"

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Diffusion Spectroscopy in Stroke

ISCHEMIC STROKE

Cerebral vascular disorder is one of the most fatal diseases despite current advances in medical science. The large number of negative clinical trials on neuroprotection in acute stroke is a pointer to the fact that translating better understanding of the pathogenesis and pathophysiology to clearly beneficial treatment strategies remains a daunting task. This project aims at elucidating the plausible biophysical events that affect water and metabolite diffusion in brain tissue after ischemia, by combining the information provided by two advanced methods of magnetic resonance (MR) diffusion imaging: diffusional kurtosis imaging and diffusion-weighted spectroscopy. Diffusion weighted imaging (DWI) has been established as a major tool for the early detection of stroke. However, information obtained using conventional DWI may be incomplete. Diffusional kurtosis (K) is a quantitative measure of the complexity or heterogeneity of the microenvironment in white and grey matter, which offers complementary information and may potentially be a more sensitive biomarker for probing pathophysiological changes. In addition, to gain more specific insights into molecular mobility in the intracellular environment, it is beneficial to assess the diffusion properties of metabolites, such as N-acetylaspartate (NAA), creatine and phosphocreatine (Cr), and choline containing compounds (Cho). Assessment of metabolite diffusion changes by diffusion-weighted spectroscopy (DWS) provides information specific to the intracellular environment. In particular, thanks to the specific compartmentation of NAA almost exclusively in neurons and of Cho in glial cells, the diffusion properties of these metabolites may provide specific insights into the pathological processes occurring independently in the two cell types. In addition, measuring a temporal profile of diffusion coefficient of these compounds may help clarify underlying pathophysiological changes in neuronal cells during acute ischemia. With the help of these two advanced methods, a proof-of-concept trial is proposed on 24 healthy subjects and 24 ischemic stroke patients. Ischemic stroke patients will be scanned three times with a 3T MR scanner (before day 10 post-stroke, around week 4 and 3 months), in order to extract diffusion kurtosis imaging (DKI) and DWS metrics and understand the dynamics of the cellular mechanisms at play in cerebral ischemia. The goal of this study is to investigate neuronal and glial metabolite diffusion changes at different time points after ischemic stroke, in both infarcted and non-infarcted hemispheres. The aim is to get non-invasively important information on the evolution of the cellular damage in this disease, and possibly distinguishing between neuronal and glial processes (by measuring the metrics extracted for these two sequences), as well as on the different mechanisms leading to metabolite diffusion changes in the two brain areas, thus providing a great impact on the strategy of treatment for patients with cerebral infarction.

Completed3 enrollment criteria

Comparing Unimanual and Bimanual Mirror Therapy for Upper Limb Recovery Post Stroke

Cerebral Vascular Accident (CVA)Stroke

The purpose of this randomized controlled study is to Examine the feasibility of a home Mirror therapy (MT) program in the NYC metropolitan area; Evaluate the effectiveness of home MT versus traditional home exercise program; and Evaluate the superiority of unimanual or bimanual MT intervention protocols for chronic stroke subjects with moderate hand deficits. Subjects from occupational therapy at the Ambulatory Care Center of NYU Langone Center with a diagnosis of cerebral vascular accident (CVA) or stroke will be divided into three (3) groups: Control Group subjects will participate in standard occupational therapy rehabilitation protocol plus a traditional home based exercise program. Experimental group 1 subjects will participate in standard rehabilitation protocol plus unimanual home based mirror therapy program Experimental group 2 subjects will participate in standard rehabilitation protocol plus bimanual home based mirror therapy program.

Completed10 enrollment criteria

The SMARTChip Stroke Study

Stroke

Stroke is one of the leading causes of death and disability in the UK and currently costs the country £7bn per year. There is an overwhelming need to accurately and rapidly triage patients to allow best use of finite NHS specialist resources for the treatment of stroke. A simple blood test of substances (the purines) that result from cellular metabolism and are produced in excess when brain cells are starved of oxygen and glucose (as occurs during a stroke) is proposed. The sensors designed by the investigators are used to measure blood purines during a procedure in which blood flow to the brain is reduced to allow surgical interventions on the major arteries that supply the brain. Previous studies by the investigators have shown that as soon as blood flow to the brain is reduced, purines are produced within minutes and are detectable in systemic arterial blood. The current project will now compare the levels of purines in the blood of stroke patients and controls. The purines will be measured on admission to hospital and 24 hours later. The occurrence and magnitude of a stroke will be determined by an MRI scan given between 24 and 72hrs after admission. This study will establish whether purines are elevated in the blood of stroke patients on admission to hospital compared to healthy controls, and whether this correlates with the size of the stroke and damage to the brain.

Completed49 enrollment criteria

Atrial Fibrillation as a Cause of Stroke and Intracranial Hemorrhage Study (The FibStroke Study)...

StrokeTransient Ischemic Attacks2 more

The aim of this study is to evaluate the role of atrial fibrillation (AF) and its treatment in relation to thromboembolic events (stroke, and transient ischemic attacks) and intracranial hemorrhage. Primary Outcome Measures: - Incidence and timing of intracranial complications (stroke,TIA, bleedings) in relation to diagnosis and anticoagulation treatment of AF during the study period; comparison of complications between those with and without anticoagulation treatment according to CHADSVASc score. Secondary Outcome Measures: The effect of anticoagulation pauses and INR level on stroke and bleeding risk; strokes within 30 days after anticoagulation pause and the prevalence of stroke and intracranila bleeding in relation to INR level < 2, 2-3 and >3. Trauma as a risk factor for intracranial bleeding: percentage and risk factors for intracranial bleeding with or without trauma. Type of preceding trauma and type of intracranial bleeding. The time relation between diagnosis of AF and type of intracranial complications: Kaplan Meier analysis of thrombotic (Stroke/TIA) and intracranial bleeding complications after 1st diagnosis of AF in patients with and without anticoagulation The risk of stroke and intracranial bleeding in relation to CHADSVASc score, HAS-BLED score and anticoagulation/antithrombotic treatment Prognosis of stroke and intracranial bleeding: 30-day mortality after stroke and intracerebral bleeding in patients with and without anticoagulation Factors related to underuse of anticoagulation treatment. Data on reasons for not starting or stopping aticoagulation in those with indication of oral anticoagulation Operations and procedure as risk factor for stroke: Frequency and type of operations performed < 30 days before stroke. Data on length of perioperative pause in anticoagulation and use of bridging therapy and timiing of stroke are collected. Cardioversions as a risk factor for stroke: Frequency of stroke and TIA < 30 days after cardioversion in relation to use of anticoagulation and CHADSVASc score The risk of stroke and intracranial bleeding in relation to type of AF (permanent, persistent, paroxysmal) and concomitant carotid disease Estimated Enrollment: 6000 patients.

Completed2 enrollment criteria

Feasibility of AmbulanCe-based Telemedicine (FACT) Study

Acute Stroke

Research on prehospital telestroke systems is recommended by the American Stroke Association, as it may facilitate early stroke diagnosis, assessment of stroke severity and selection of patients for specific stroke treatments The experience with prehospital telemedicine for assessment of stroke severity is limited. Prehospital telestroke is a very promising concept, facilitating specialized stroke care in very early stage based on integration of bidirectional audiovisual communication with point of care laboratory analysis, vitals and decision support software. The aim of this prospective study is to investigate the safety, the technical feasibility and the reliability of in-ambulance telemedicine using a prototype third generation telemedicine system (PreSSUB 3.0).

Completed1 enrollment criteria

Door-to-door Survey of Cardiovascular Health, Stroke and Ischemic Heart Disease in Atahualpa

StrokeIschemic Heart Disease

The aim of the Atahualpa project is to evaluate the cardiovascular (CVH) status of the inhabitants of a rural village of coastal Ecuador as well as to determine the prevalence and retrospective incidence of stroke and ischemic heart disease. The protocol may be used as a pilot for large-scale studies attempting to evaluate the CVH of rural or even urban centers of Latin America, to implement cost-effective strategies directed to reduce the burden of stroke and cardiovascular diseases in the population at large.

Completed2 enrollment criteria

Effect of Atorvastatin on the Frequency of Ventilator-associated Pneumonia in Patients With Ischemic...

Ventilator-associated PneumoniaIschemic Stroke

Ventilator-associated pneumonia (VAP) is an important cause of morbidity and mortality in ventilated critically ill patients specially in intensive care unit (ICU). It is associated with an increased duration of mechanical ventilation, high death rates and increased healthcare costs in China. However, VAP is preventable and many practices have been demonstrated to reduce the incidence of this disease, but the morbidity is still so high. So much more methods of prevention should be needed to reduce the incidence of VAP. Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) present anti-inflammatory and immunomodulatory effects besides their ability to regulate cholesterol composition. So it is hypothesized that early use of statin may prevent some of the infection disease such as VAP. Actually, Two studies have showed that statin treatment is associated with reduced risk of pneumonia. However, the relationship between statins and reduced risk of pneumonia is not consistent. After reviewing some of the guidelines,meta analyses and system reviews, the investigator find that advanced age,immune suppression from disease or medication and specially depressed level of consciousness are the risk factors of VAP. So the investigator assumes that early use of statin may give us a favorable outcome in the patients with coma or in the patients with severe disease (Acute Physiology and Chronic Health Evaluation II score > 15 or Glasgow coma score < 7). In addition there is no prospective study to investigate the role of statins in VAP in the patients with ischemic stroke. The investigator hopes that this study can approve the relationship between statins and reduced risk of VAP in the patients with ischemic stroke. And it can improve the processes,outcomes and costs of critical care as well.

Unknown status10 enrollment criteria

Smoking Cessation Interventions in Stroke Patients

Ischemic Stroke

The primary objective of the present randomized controlled trial is to compare the effectiveness of three anti-smoking interventions of different intensities. It has been hypothesised that early follow-up visits facilitate post-stroke smoking cessation in patients hospitalized because of first-ever ischemic stroke.

Unknown status10 enrollment criteria

Genetic Studies to Identify Stroke Subtypes and Outcome

Cerebrovascular DiseaseStroke

This study will characterize the gene response of the body's immune and inflammatory cells to stroke. There is a wide variation in stroke risk, stroke outcome, and response to clot-busting therapy for stroke. This variation may be due to differences in people's response to injury or infection, or to differences in genetic make-up between individuals. Genes store the biological information that determines the body's response to injury or infection. This study will analyze the activity of a large number of genes to try to learn which genes might be related to patient outcome. This, in turn, may lead to an understanding of which gene profiles are related to increased stroke risk and increased disability or death. Healthy volunteers over age 21 and stroke patients over age 21 who are admitted to the NIH Stroke Program at Suburban Hospital in Bethesda, Md., may be eligible for this study. Volunteers will be screened with a medical history, blood pressure and pulse measurements, electrocardiogram, and neurological examination. Participants will have 20 to 35 milliliters (about an ounce) of blood drawn for genetic studies. The genetic material will be extracted from the white blood cells and analyzed for normal and abnormal gene activity related to stroke. ...

Completed20 enrollment criteria

Tactile Learning in Stroke Patients

Stroke

This study will determine if stimulation of the stroke-injured side of the brain combined with stimulation to the paralyzed hand can temporarily improve the sense of touch in stroke patients. Healthy normal volunteers and people who have had a single stroke within 3 months of entering the study that affected one side of the brain may be eligible for this study. All participants must be between 18 and 90 years old and must be right-handed. Candidates are screened with a medical history, neurological examination and magnetic resonance imaging (MRI) of the brain if one has not been done within 1 year of entering the study. Participants undergo the following tests and procedures during four 2-day sessions over about 6 weeks: Peripheral high-frequency stimulation: Small loudspeakers are taped to the fingertips and simple tactile pulses are passed through the skin. Stimulation may be sham or real. Transcranial direct current stimulation: Two small rubber electrodes are taped to the head - one above the eye and the other on the back of the head. A current is passed between the two electrodes. Stimulation may be sham or real. MRI: The subject lies in the scanner, a metal cylinder surrounded by a magnetic field, for about 40 minutes, lying still for up to 40 minutes at a time. An electrical stimulation is applied to the fingers of the right and left hand in separate sessions. Earplugs are worn to muffle the loud noises during the scanning. Functional MRI measures blood flow changes in the brain during the performance of specific tasks. Behavioral measurements: Grating orientation task: The subject responds as quickly as possible to a touch stimulus to the finger by saying whether the direction of the stimulus is vertical or horizontal. Haptic object recognition task: The subject is given five categories of unfamiliar objects in the shape of cubes. During the task, identical objects are hidden in a sack. With eyes closed, the subject is asked to identify and find the objects from the sack as quickly as possible. Pegboard test: The subject is asked to place several pegs into a corresponding hole of a pegboard as soon as possible. Tapping task: The subject is asked to tap a metal stick on a metal plate as quickly as possible for 1 minute. Paired-pulse transcranial magnetic stimulation: This test measures changes in brain activity. A wire coil is held on the scalp and a brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. The subject hears a click and may fee a pulling sensation on the skin under the coil, and there may be a twitch in the muscles of the face, arm or leg. Subjects may be asked to tense certain muscles slightly or perform other simple actions. Paired-pulse somatosensory evoked potential mapping: This test measures brain activity in another brain area. The subject is seated in a chair with eyes closed. One electrode is placed above the eye and two others are placed on the back of the head. A short electrical stimulus is applied to a nerve in the wrist and brain activity is recorded while the stimulus is applied. Surface electromyography: This test measures the electrical activity of muscles. Electrodes are filed with a conductive gel and taped to the skin. Visual analog and mood scale: Subjects complete questionnaires about their attention, fatigue and mood.

Completed20 enrollment criteria
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