View clinical trials related to Cerebral Blood Flow.
Filter by:To investigate the effect of levcromakalim/placebo infusion on cranial arteries after glibenclamide administration.
Cognitive performance is negatively related to an impaired glucose metabolism, possibly due to impairments in brain vascular function. Supported by the statement from the American Heart and American Stroke Association that healthy plant-based diets, which consist of soy foods, protect against cognitive decline, we now hypothesize that soy-induced changes in glucose metabolism cause beneficial effects on brain vascular function thereby improving cognitive performance. The primary objective of this intervention study is thus to evaluate in elderly men and women the effect of a 16-week soy intervention on cerebral blood flow, as quantified by the non-invasive gold standard magnetic resonance imaging (MRI) perfusion method Arterial Spin Labeling (ASL). Cerebral blood flow is a robust and sensitive physiological marker of brain vascular function. Secondary objectives are to examine effects on glucose metabolism using the oral glucose tolerance test and cognitive performance as assessed with a neurophysiological test battery.
Previous research shows that a diet high in fat has harmful effects on gut health. This increases the chance of developing obesity-related diseases (such as type 2 diabetes) and disrupts cognition and mood. Research has suggested that gut health can be improved by taking certain supplements, including resveratrol (a polyphenol found primarily in red grape skins). Resveratrol has also been shown to improve brain blood flow and possibly brain function - however, there is limited research studying this. This study will investigate the effects of 12 weeks daily consumption of resveratrol on cognitive function, cerebral blood flow, gut microbiota and systemic inflammation in overweight and obese healthy adults.
Cognitive performance is negatively related to an impaired glucose metabolism, possibly due to impairments in brain vascular function. Supported by the statement from the American Heart and Stroke Association that physical exercise is one of the most effective strategies to protect against cognitive decline, we now hypothesize that exercise-induced changes in glucose metabolism cause beneficial effects on brain vascular function thereby improving cognitive performance. The primary objective of this intervention study is thus to evaluate in sedentary elderly men the effect of a 8-week aerobic-based exercise program on cerebral blood flow, as quantified by the non-invasive gold standard magnetic resonance imaging (MRI) perfusion method Arterial Spin Labeling (ASL). Cerebral blood flow is a robust and sensitive physiological marker of brain vascular function. Secondary objectives are to examine effects on glucose metabolism using the oral glucose tolerance test and cognitive performance as assessed with a neurophysiological test battery.
The primary objective of this study is to confirm and compare the effect of methods of Low-level light therapy (LED-T) in the mild cognitive impairment.
Objectives: Investigate the acute NIV effects on CBF and cognitive functions in COPD patients. Methods: Nine non-hypercapnic stable COPD subjects (FEV1/FVC < lower limit of normal) and twelve healthy controls were enrolled. CBF (transcranial Doppler), cognitive functions, respiratory and cardiovascular response were tested at baseline, during and after non-invasive ventilation.
Multiple studies in the spinal cord injury (SCI) population have documented deficits in learning and memory (LM) and processing speed (PS) that adversely impact daily life and the ability to benefit from rehabilitation. The investigators have previously attributed the cognitive deficits demonstrated in the SCI population to low blood pressure (BP) and cerebral blood flow (CBF) and are currently conducting a study to determine the effect of a 30-day elevation in BP (using midodrine hydrochloride - an alpha agonist) on CBF and cognitive performance compared to placebo in hypotensive individuals with SCI. In addition, the investigators believe that cognitive behavior therapy (CBT) may improve cognition independent of changes in BP and CBF in individuals with SCI. The current randomized clinical trial (RCT) will examine the efficacy of 2 treatment protocols shown to be effective in improving cognitive performance in other neurologically impaired populations for use in persons with SCI demonstrating (1) LM impairment and/or (2) PS impairment on objective measures of cognitive functioning during a complete Neuropsychological assessment. Two methods of outcome assessment will be used to examine treatment impact: (1) a traditional Neuropsychological assessment (NP) and (2) an assessment of global functioning (AGF) composed of broader outcome measures that examine the impact of the treatment on everyday life activities. In this way, the investigators will be able to objectively evaluate the presence or absence of changes in memory performance through a NP assessment, while also evaluating the impact of this treatment protocol on everyday life through the AGF. While most studies evaluating the efficacy of cognitive retraining usually employ a pre- and post-training evaluation, such evaluations have been criticized for their lack of ecological validity (i.e., real world generalizability). The present design allows the assessment of the efficacy of these treatment techniques within an SCI population using traditional measures, as well as the assessment of the impact that treatment has on everyday life. The investigators will additionally evaluate the long-term efficacy by including a 6-month post-treatment follow-up. Few studies examine long-term effects, but given the time, labor and expense involved, it is critical to demonstrate long-term efficacy.
Cerebral autoregulation can be explained by a tight coupling between oxygen supply and demand of the brain, and is essential to maintain a constant cerebral blood flow (CBF) in the context of changes in cerebral perfusion pressure. In this study, investigators use Near-infrared spectroscopy (NIRS) to monitor cerebral autoregulation.
While treatment strategies for OH have been identified for use in persons with acute SCI, the field of SCI medicine lacks a gold standard for treatment thresholds and well-defined outcome parameters. Comprehensively documenting the impact of orthostatic hypotension (OH), regardless of symptoms, during acute rehabilitation and identifying the effects of two different treatment approaches on therapy participation and adherence to an intended rehabilitation plan could have a significant impact on clinical practice in the acute rehabilitation setting following SCI.
Dysregulation of blood pressure (BP), secondary to decentralized autonomic nervous system (ANS) control of the cardiovascular system, often results in chronic hypotension and orthostatic hypotension (OH) in persons with spinal cord injury (SCI), particularly in those with high cord lesions (i.e., above T6). While most hypotensive individuals with chronic SCI remain asymptomatic and do not complain of symptoms associated with cerebral hypoperfusion, evidence of reduced resting cerebral blood flow (CBF) has been reported in association with low systemic BP in the SCI and non-SCI populations. Reduced CBF in hypotensive individuals may lead to cognitive dysfunction, and we reported significantly impaired memory and marginally impaired attention processing in hypotensive individuals with SCI compared to a normotensive SCI cohort. Furthermore, we found that CBF was not increased during cognitive testing in individuals with SCI, which may contribute to impaired cognitive function compared to non-SCI controls. Although asymptomatic hypotension may have an adverse impact on cognitive function and quality of quality of life (QOL) clinical management of this condition is extremely low. In fact, we reported that while nearly 40% of Veterans with SCI were hypotensive, less than 1% carried the diagnosis of hypotension or were prescribed an anti-hypotensive medication. The discrepancy between incidence and treatment of asymptomatic hypotension in the SCI population may relate to a paucity of treatment options which are supported by rigorous clinical trials documenting safe and effective use of anti-hypotensive therapy on BP, CBF and cognitive function. We hypothesize these study medications may increase systolic blood pressure to the normal range and improve cerebral blood flow velocity. Results and conclusions will not be removed from the record.