View clinical trials related to Cerebrovascular Accident.
Filter by:After acute stroke, baroreflex sensitivity (BRS) is impaired. This impaired acute stage BRS has been reported to be predictive of worsen outcome years after stroke in general. However, it is not very clear if the impaired acute stroke BRS would actually persist months after the acute stage. It is also not clear that such change, if any, would correlate with the functional outcome or prognosis after stroke. The trial is to investigate the longitudinal time course of BRS after ischemic stroke up to the 6th month post stroke and to see if there is any correlation of the changes in BRS with the functional outcome parameters using NIHSS and mRS scores throughout this period.
According to the theory of wave transmission, the speed of wave transmission is dependent on the nature of the transmission medium, which is the vessel wall for pulse wave transmission. Then, the pulse wave velocity is related to the mechanical property of the vessel wall. The mechanical property of the vessel wall is determined by the texture of the vessel wall and the contraction status of the smooth muscle within the vessel wall. Because the texture of the vessel wall could not be changed in a short duration, the sympathetic nerve activity, which controls the contractibility of the smooth muscle, becomes the only determinant factor of pulse wave velocity. So, pulse wave velocity may reflect the status of sympathetic nerve activity. The purpose of this project is to use the pulse wave velocity to measure the sympathetic activity of stroke and spinal cord patients. The present project plans to measure the pulse wave simultaneously at four limbs by pressure receptors, and use the electrocardiogram as the reference to synchronize the recorded pulse wave at different vessels, using the corrected data to calculate the pulse wave velocity. With the pulse wave velocity of different vessels, we, the investigators at National Taiwan University Hospital, can understand the local sympathetic nerve activity in different diseases and different sites. The first year, we will set up the equipment for measuring the pulse wave velocity, and then apply it to 20 healthy subjects to adjust the measurement error and ascertain the reproducibility of the machine. The second year, we will apply the measurement to 15 complete cervical cord injury individuals and 15 healthy subjects in different erected angles by a tilting table. This procedure will make us understand the response of sympathetic nerve activity to different postures in normal subjects and cervical cord injury patients. The third year, we will apply the measurement to 30 cerebrovascular accident patients to understand the change of sympathetic nerve activity after having a stroke. By comparing the clinical information, we hope to clear up the relationship between sympathetic nerve activity and pulse wave velocity.
Ultrasonographic examination has long been used to assess the swallowing function. It has the advantages of no ionizing radiation on examination and the possibility of using the real food instead of the barium meal in testing. Thus, the subjects can be examined repeatedly and in a more physiological status of swallowing. However, the ultrasonographic examination is only used in assessing the oral phase of swallowing. It can accurately visualize the tongue movement, measure the oral transit time of bolus, and sometimes the hypoid bone motion, but has not been applied on the evaluation of pharyngeal phase of swallowing. Physically, laryngeal elevation is an essential component of the swallowing movement on pharyngeal phase. It ensures the occlusion of airway and opening of criopharymgeus muscle, and thus prevents the aspiration. To evaluate the laryngeal elevation is crucial point in managing the dysphagic patients. The purpose of this project is to measure the laryngeal elevation in normal and in dysphagic patients with cerebrovascular (CVA) accident using ultrasonographic techniques. This work will include four group subjects. The first group consists of 20 young subjects (< 40 years); the second group consists of 20 age-matched normal subjects; the third group consists of 20 CVA patients without swallowing problems, and the fourth group consists of 20 CVA patients with dysphagia, which was proven by VFSS. The laryngeal elevation is detected by ultrasound with the transducer placing between the hyoid bone and thyroid cartilage. The two markers are easily detected on sonogram because of the presence of acoustic shadow, a specific character of bony structure on sonogram. The distance between the hyoid bone and thyroid cartilage before and during swallowing is measures and compared among the groups. The distance change of the patients with dysphagia is further compared with that defined by VFSS. With the result of this study, we will understand the status of laryngeal elevation during swallowing in normal and dysphagic subjects, and further determine the accuracy of ultrasonographic measurement in measuring the laryngeal elevation. With this knowledge, we might extend the usage of ultrasonographic examination on evaluating swallowing function.
The International Pediatric Stroke Study (IPSS) was established in 2003 as a multi-center, multi-national clinical research registry. Over the years, it has grown to become a highly successful study vehicle for pediatric stroke research across over 100 institutions worldwide. Today, The IPSS continues to serve as the global clinical data and imaging core for multi-disciplinary pediatric experts who perform international collaborative research to better understand, prevent, and improve outcomes in pediatric stroke. The robust dataset and cohesive network enable high caliber and ground-breaking research in the field. Participating sites enroll neonates or children who have had an ischemic stroke or are at high risk of having a stroke into the registry. Participants have their medical and research records reviewed for information about their stroke and abstracted into a secure electronic database called REDCap. The IPSS also provides an attractive imaging platform (through the Stroke Imaging Lab for Children, SILC, housed at SickKids) for sites to share clinically acquired brain images that will complement the clinical dataset. The clinical and imaging datasets will improve our understanding of the processes underlying plasticity and recovery in childhood stroke.
The purpose of this study is to learn more about stroke and obtain information that may serve as the basis for future investigations. It will 1) establish a registry of patients with cerebrovascular disease (stroke); 2) characterize the natural history of acute stroke and transient ischemic attacks (TIA)-an interruption of blood flow to the brain that causes stroke symptoms for a short period of time); and 3) evaluate the data to generate ideas for future studies. Patients 18 years of age or older with suspected acute stroke or TIA may be eligible for this study. Subjects will be recruited from patients who present with stroke at the emergency department of Suburban Hospital in Bethesda, Maryland. The study will gather data collected from diagnostic and laboratory tests the patient undergoes as part of standard medical care, including findings of medical and neurological examinations and other tests. In addition, studies will be done for research purposes only to gather data about stroke and TIA. These may include the following: - Blood and urine tests not more than 2 tablespoons of blood will be drawn for various tests. - Electrocardiogram (EKG) (heart tracing)-electrodes placed on the chest wall detect the heartbeat and heart rhythm. - Computed tomography (CT) scan of the head-specialized X-rays are used to obtain images of the brain. - Magnetic resonance imaging (MRI) of the brain-a strong magnetic field and radio waves are used to produce images that provide information about the brain tissue and blood vessels. - Transcranial Doppler (TCD)-sound waves are used to image the arteries of the brain and neck. - Echocardiogram-sound waves are used to image the heart and evaluate heart function. Patients may be asked to return to Suburban Hospital for follow-up testing in 1, 3, and/or 12 months, when some of these tests may be repeated to assess changes over time