Active clinical trials for "Stroke"

To investigate the relationship between the integrity of the white matter, including the corticospinal tracts and the corpus callosum, with the recovery of lower extremity function in patients with cerebral stroke at the subacute and chronic stages.

Aim of this study is to define a CT-based "tissue window" for stroke thrombolysis. Our primary hypothesis is that patients with a "tissue window" (favourable non-contrast CT (NCCT) scan and an intracranial occlusion on CT angiography (CTA) or perfusion-CT-mismatch" (area of reduced cerebral blood flow (CBF) > area of reduced cerebral blood volume (CBV)) represent a significant proportion (> 20%)of acute stroke patients and therefore are an important target group for future interventional studies patients with a "tissue window" suffer an unfavourable outcome (> 50 % mRS =>4 at 3 months)if the occluded artery was not recanalized.

The purpose of this study is to find the genes that increase the risk of developing an ischemic stroke using DNA samples collected from concordant (stroke-affected) sibling pairs.

This study will determine how people who have had a stroke learn to perform a movement by observation, as compared with people who have not had a stroke. Normally, a person learns a new hand movement automatically by observing the movement performed by others. Improvement with practice also relies on visual feedback. This "observational training" - i.e., the repeated observation of a movement - is sufficient for normal individuals to learn a movement. This study will examine brain activity related to motor learning in stroke patients and in healthy control subjects to see whether stroke patients process visual-motor information the same way normal subjects do. Normal volunteers and stroke patients between 18 and 75 years of age may be eligible for this study. Patients must have had paralysis on one side of the body due to a stroke that occurred at least 3 months before entering the study. Candidates who have not had a recent health screening will have a clinical and neurological examination. Participants undergo the following procedures: Brain magnetic resonance imaging (MRI), if one has not been done recently. This test uses a strong magnetic field and radio waves to obtain images of body organs and tissues. The subject lies on a table that can slide in and out of the cylindrical scanner and wears earplugs to muffle loud noises caused by switching of magnetic fields. Scanning time varies from 20 minutes to 3 hours, with most sessions lasting 45 to 90 minutes. Task training. The subject practices the task to be performed during functional MRI (see below). The subject makes finger tapping movements, then watches finger movements on a video screen for several minutes, during which time the movie stops from time to time without warning. When the movie stops, the subject must reproduce the last finger movement that appeared on the screen. During this session, the electrical signals of the subject's forearm muscles are recorded at the skin surface. This session lasts up to 3 hours. Functional MRI. The subject undergoes MRI scanning while performing the same tasks done in the training session. This session lasts about 3 hours.

To investigate the relationship of vascular cell phenotypes to atherosclerosis.

To conduct a 25-year follow-up of the surviving participants in the Western Collaborative Group Study, the first large prospective study of coronary heart disease risk factors to incorporate direct assessment of Type A behavior.

This study will use transcranial magnetic stimulation (TMS) to identify interactions between the unaffected and affected side of the brain in stroke patients. Results from previous studies suggest that after a stroke, the motor cortex (part of the brain that controls movement) of the unaffected side of the brain might negatively influence the motor cortex of the affected side. TMS is a procedure that delivers brief electrical currents that stimulate the brain. Studies of a small number of patients have shown that TMS can cause a temporary decrease in activity of the motor cortex. Healthy normal volunteers and chronic stroke patients may be eligible for this study. Subjects may participate in up to four sessions of reaction time (speed of motor response) testing. They will perform a series of movements with the index and middle fingers of either the left or right hand in response to a signal from a computer monitor. The time it takes to do the tasks will be measured and scored. There will be rest periods during each session. TMS will be done each session to examine how the motor cortex affects recovery of function after stroke. For this procedure, an insulated wire coil is placed on the scalp. A brief electrical current is passed through the coil, creating a magnetic pulse that stimulates the brain. Depending on where the coil is placed, the stimulation may cause a muscle twitch (sometimes strong enough to move the limb), a feeling of movement or tingling in a limb, or twitching of the jaw. During stimulation, the subject may be asked to tense certain muscles slightly or to perform other simple actions. The electrical activity in the muscles activated by the stimulation will be recorded using metal electrodes taped to the skin over the muscles. Subjects will also be asked to draw a mark on a line on paper to rate their attention and level of fatigue, and how well they think they are executing the tasks. Participants will also have magnetic resonance imaging (MRI). This procedure uses a strong magnetic field and radio waves to provide detailed images of the brain. During the scanning, the subject wears earplugs to muffle loud thumping sounds that occur with electrical switching of the radio frequency circuits. The subject can communicate with the staff member performing the study at all times through an intercom system.

To extend mortality followup through 25 years for two cohorts of men in the Multiple Risk Factor intervention Trial (MRFIT): the 361,662 men screened and the 12,866 men randomized, and to pursue the general aim of elucidating unresolved research issues on the epidemiology, natural history, etiology, prevention, and control of major chronic diseases, particularly cardiovascular and neoplastic diseases and diabetes.

DISPLACE is a three part, multi-center U.S. based study to evaluate the barriers to stroke screening and prevention in children with sickle cell anemia (SCA). In the United States, TCD (Transcranial Doppler ultrasound) is a proven method of screening children with SCA for stroke. However, many children are not getting the screening they need. This study will examine the issues that hinder and help children get the screening at 28 different hospitals and sickle cell centers to improve care for all children with sickle cell anemia. The investigators will then plan a study (part 3) aimed to improve stroke screening and prevention in sickle cell anemia.

There are few published data on the patterns of parenchymal imaging abnormalities in a context of cerebral venous thrombosis (CVT). The objectives of the present study were to describe the patterns of parenchymal lesions associated with CVT and to determine the lesion sites.