AnatomyOrganismsDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPsychiatry and PsychologyPhenomena and ProcessesDisciplines and OccupationsAnthropology, Education, Sociology and Social PhenomenaTechnology, Industry, AgricultureInformation ScienceHealth CareGeographicals
Cerebrovascular CirculationBlood CirculationExtracorporeal CirculationPulmonary CirculationVertebrobasilar InsufficiencyPosterior Cerebral ArteryVertebral ArteryInfarction, Posterior Cerebral ArteryBasilar ArteryCerebral AngiographySyndromeHypoplastic Left Heart SyndromeHeart Defects, CongenitalNorwood ProceduresUmbilical ArteriesFontan ProcedureBlalock-Taussig ProcedureFetusMetabolic Syndrome XGinkgo bilobaHeparan Sulfate ProteoglycansPhotometryPoloxaleneBiological MarkersBlood-Brain BarrierPhotographyAnimal FinsLightBathsSunburnStrokePerfusion ImagingBrain IschemiaBrainContrast MediaPerfusionCerebral InfarctionSoftwareReagent Kits, DiagnosticImage Processing, Computer-AssistedSensitivity and SpecificityReproducibility of ResultsPrivacyConfidentialityComputer SecurityInformed ConsentHearing LossHearingDisease OutbreaksCongresses as TopicSocieties, MedicalPrince Edward IslandEducation, GraduateCardiologyPublishingJapan
Cerebrovascular Circulation: The circulation of blood through the BLOOD VESSELS of the BRAIN.Blood Circulation: The movement of the BLOOD as it is pumped through the CARDIOVASCULAR SYSTEM.Extracorporeal Circulation: Diversion of blood flow through a circuit located outside the body but continuous with the bodily circulation.Pulmonary Circulation: The circulation of the BLOOD through the LUNGS.Vertebrobasilar Insufficiency: Localized or diffuse reduction in blood flow through the vertebrobasilar arterial system, which supplies the BRAIN STEM; CEREBELLUM; OCCIPITAL LOBE; medial TEMPORAL LOBE; and THALAMUS. Characteristic clinical features include SYNCOPE; lightheadedness; visual disturbances; and VERTIGO. BRAIN STEM INFARCTIONS or other BRAIN INFARCTION may be associated.Posterior Cerebral Artery: Artery formed by the bifurcation of the BASILAR ARTERY. Branches of the posterior cerebral artery supply portions of the OCCIPITAL LOBE; PARIETAL LOBE; inferior temporal gyrus, brainstem, and CHOROID PLEXUS.Vertebral Artery: The first branch of the SUBCLAVIAN ARTERY with distribution to muscles of the NECK; VERTEBRAE; SPINAL CORD; CEREBELLUM; and interior of the CEREBRUM.Infarction, Posterior Cerebral Artery: NECROSIS induced by ISCHEMIA in the POSTERIOR CEREBRAL ARTERY distribution system which supplies portions of the BRAIN STEM; the THALAMUS; TEMPORAL LOBE, and OCCIPITAL LOBE. Depending on the size and location of infarction, clinical features include OLFACTION DISORDERS and visual problems (AGNOSIA; ALEXIA; HEMIANOPSIA).Basilar Artery: The artery formed by the union of the right and left vertebral arteries; it runs from the lower to the upper border of the pons, where it bifurcates into the two posterior cerebral arteries.Cerebral Angiography: Radiography of the vascular system of the brain after injection of a contrast medium.Syndrome: A characteristic symptom complex.Hypoplastic Left Heart Syndrome: A condition caused by underdevelopment of the whole left half of the heart. It is characterized by hypoplasia of the left cardiac chambers (HEART ATRIUM; HEART VENTRICLE), the AORTA, the AORTIC VALVE, and the MITRAL VALVE. Severe symptoms appear in early infancy when DUCTUS ARTERIOSUS closes.Heart Defects, Congenital: Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.Norwood Procedures: A set of surgical procedures performed to establish sufficient outflow to the systemic circulation in individuals with univentricular congenital heart malformations, such as HYPOPLASTIC LEFT HEART SYNDROME, and MITRAL VALVE atresia, associated with systemic outflow obstruction. Follow-on surgeries may be performed and consist of a HEMI-FONTAN PROCEDURE as the stage 2 Norwood procedure and a FONTAN PROCEDURE as the stage 3 Norwood procedure.Umbilical Arteries: Specialized arterial vessels in the umbilical cord. They carry waste and deoxygenated blood from the FETUS to the mother via the PLACENTA. In humans, there are usually two umbilical arteries but sometimes one.Fontan Procedure: A procedure in which total right atrial or total caval blood flow is channeled directly into the pulmonary artery or into a small right ventricle that serves only as a conduit. The principal congenital malformations for which this operation is useful are TRICUSPID ATRESIA and single ventricle with pulmonary stenosis.Blalock-Taussig Procedure: A cardiovascular procedure performed to create a blood supply to the PULMONARY CIRCULATION. It involves making a connection between the subclavian, or carotid branch of the AORTA, or the AORTIC ARCH to the PULMONARY ARTERY.Fetus: The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.Metabolic Syndrome X: A cluster of metabolic risk factors for CARDIOVASCULAR DISEASES and TYPE 2 DIABETES MELLITUS. The major components of metabolic syndrome X include excess ABDOMINAL FAT; atherogenic DYSLIPIDEMIA; HYPERTENSION; HYPERGLYCEMIA; INSULIN RESISTANCE; a proinflammatory state; and a prothrombotic (THROMBOSIS) state. (from AHA/NHLBI/ADA Conference Proceedings, Circulation 2004; 109:551-556)Ginkgo biloba: The only specie of the genus Ginkgo, family Ginkgoacea. It is the source of extracts of medicinal interest, especially Egb 761. Ginkgo may refer to the genus or species.Heparan Sulfate Proteoglycans: Ubiquitous macromolecules associated with the cell surface and extracellular matrix of a wide range of cells of vertebrate and invertebrate tissues. They are essential cofactors in cell-matrix adhesion processes, in cell-cell recognition systems, and in receptor-growth factor interactions. (From Cancer Metastasis Rev 1996; 15(2): 177-86; Hepatology 1996; 24(3): 524-32)Photometry: Measurement of the various properties of light.Poloxalene: A copolymer of polyethylene and polypropylene ether glycol. It is a non-ionic polyol surface-active agent used medically as a fecal softener and in cattle for prevention of bloat.Biological Markers: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.Blood-Brain Barrier: Specialized non-fenestrated tightly-joined ENDOTHELIAL CELLS with TIGHT JUNCTIONS that form a transport barrier for certain substances between the cerebral capillaries and the BRAIN tissue.Photography: Method of making images on a sensitized surface by exposure to light or other radiant energy.Animal Fins: Membranous appendage of fish and other aquatic organisms used for locomotion or balance.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Baths: The immersion or washing of the body or any of its parts in water or other medium for cleansing or medical treatment. It includes bathing for personal hygiene as well as for medical purposes with the addition of therapeutic agents, such as alkalines, antiseptics, oil, etc.Sunburn: An injury to the skin causing erythema, tenderness, and sometimes blistering and resulting from excessive exposure to the sun. The reaction is produced by the ultraviolet radiation in sunlight.Stroke: A group of pathological conditions characterized by sudden, non-convulsive loss of neurological function due to BRAIN ISCHEMIA or INTRACRANIAL HEMORRHAGES. Stroke is classified by the type of tissue NECROSIS, such as the anatomic location, vasculature involved, etiology, age of the affected individual, and hemorrhagic vs. non-hemorrhagic nature. (From Adams et al., Principles of Neurology, 6th ed, pp777-810)Perfusion Imaging: The creation and display of functional images showing where the blood flow reaches by following the distribution of tracers injected into the blood stream.Brain Ischemia: Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Contrast Media: Substances used to allow enhanced visualization of tissues.Perfusion: Treatment process involving the injection of fluid into an organ or tissue.Cerebral Infarction: The formation of an area of NECROSIS in the CEREBRUM caused by an insufficiency of arterial or venous blood flow. Infarcts of the cerebrum are generally classified by hemisphere (i.e., left vs. right), lobe (e.g., frontal lobe infarction), arterial distribution (e.g., INFARCTION, ANTERIOR CEREBRAL ARTERY), and etiology (e.g., embolic infarction).Software: Sequential operating programs and data which instruct the functioning of a digital computer.Reagent Kits, Diagnostic: Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Confidentiality: The privacy of information and its protection against unauthorized disclosure.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Informed Consent: Voluntary authorization, by a patient or research subject, with full comprehension of the risks involved, for diagnostic or investigative procedures, and for medical and surgical treatment.Hearing Loss: A general term for the complete or partial loss of the ability to hear from one or both ears.Hearing: The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Congresses as Topic: Conferences, conventions or formal meetings usually attended by delegates representing a special field of interest.Societies, Medical: Societies whose membership is limited to physicians.Prince Edward Island: An island in the Gulf of St. Lawrence constituting a province of Canada in the eastern part of the country. It is very irregular in shape with many deep inlets. Its capital is Charlottetown. Discovered by the French in 1534 and originally named Ile Saint-Jean, it was renamed in 1799 in honor of Prince Edward, fourth son of George III and future father of Queen Victoria. (From Webster's New Geographical Dictionary, 1988, p981 & Room, Brewer's Dictionary of Names, 1992, p433)Education, Graduate: Studies beyond the bachelor's degree at an institution having graduate programs for the purpose of preparing for entrance into a specific field, and obtaining a higher degree.Cardiology: The study of the heart, its physiology, and its functions.Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Japan

The functional anatomy of the normal human auditory system: responses to 0.5 and 4.0 kHz tones at varied intensities. (1/8163)

Most functional imaging studies of the auditory system have employed complex stimuli. We used positron emission tomography to map neural responses to 0.5 and 4.0 kHz sine-wave tones presented to the right ear at 30, 50, 70 and 90 dB HL and found activation in a complex neural network of elements traditionally associated with the auditory system as well as non-traditional sites such as the posterior cingulate cortex. Cingulate activity was maximal at low stimulus intensities, suggesting that it may function as a gain control center. In the right temporal lobe, the location of the maximal response varied with the intensity, but not with the frequency of the stimuli. In the left temporal lobe, there was evidence for tonotopic organization: a site lateral to the left primary auditory cortex was activated equally by both tones while a second site in primary auditory cortex was more responsive to the higher frequency. Infratentorial activations were contralateral to the stimulated ear and included the lateral cerebellum, the lateral pontine tegmentum, the midbrain and the medial geniculate. Contrary to predictions based on cochlear membrane mechanics, at each intensity, 4.0 kHz stimuli were more potent activators of the brain than the 0.5 kHz stimuli.  (+info)

Loss of endothelium and receptor-mediated dilation in pial arterioles of rats fed a short-term high salt diet. (2/8163)

A high salt diet often is regarded as an accessory risk factor in hypertension, coincidental to the deleterious effect of high blood pressure on vasodilator function. The aim of this study was to determine whether short-term ingestion of a high salt diet per se impairs vasodilator function in the cerebral circulation independent of blood pressure changes. Adult Sprague-Dawley rats were fed a normal salt (0.8%) or high salt (4%) diet for 3 days. Mean arterial pressures were similar in the normal and high salt groups (123+/-2 and 125+/-2 mm Hg, respectively). Subsequently, the responses of the in situ pial arterioles to acetylcholine, iloprost, and sodium nitroprusside were determined in cranial windows using intravital videomicroscopy. Pial arterioles of rats fed normal and high salt diets showed similar resting diameters of 69+/-2 and 72+/-3 microm, respectively, but their reactivity patterns to vasodilator stimuli were markedly different. Arterioles of rats fed a normal salt diet dilated progressively up to 17+/-3% in response to the endothelium-dependent agent acetylcholine (10(-9) to 10(-6) mol/L) and dilated by 22+/-2% in response to the prostaglandin I2 receptor agonist iloprost (3x10(-11) mol/L). In contrast, pial arterioles of rats fed a high salt diet constricted by 4+/-3% and 8+/-2% in response to acetylcholine and iloprost, respectively. Sodium nitroprusside (10(-6) mol/L), a nitric oxide donor, dilated pial arterioles of rats fed low and high salt diets by a similar amount (19+/-3% and 16+/-2%, respectively), suggesting that signaling mechanisms for dilation distal to the vascular smooth muscle membrane were intact after high salt intake. These results provide the first evidence that the short-term ingestion of a high salt diet may severely impair the vasodilator function of the in situ cerebral microcirculation independent of blood pressure elevation.  (+info)

Parametric mapping of cerebral blood flow deficits in Alzheimer's disease: a SPECT study using HMPAO and image standardization technique. (3/8163)

This study assessed the accuracy and reliability of Automated Image Registration (AIR) for standardization of brain SPECT images of patients with Alzheimer's disease (AD). Standardized cerebral blood flow (CBF) images of patients with AD and control subjects were then used for group comparison and covariance analyses. METHODS: Thirteen patients with AD at an early stage (age 69.8+/-7.1 y, Clinical Dementia Rating Score 0.5-1.0, Mini-Mental State Examination score 19-23) and 20 age-matched normal subjects (age 69.5+/-8.3 y) participated in this study. 99mTc-hexamethyl propylenamine oxime (HMPAO) brain SPECT and CT scans were acquired for each subject. SPECT images were transformed to a standard size and shape with the help of AIR. Accuracy of AIR for spatial normalization was evaluated by an index calculated on SPECT images. Anatomical variability of standardized target images was evaluated by measurements on corresponding CT scans, spatially normalized using transformations established by the SPECT images. Realigned brain SPECT images of patients and controls were used for group comparison with the help of statistical parameter mapping. Significant differences were displayed on the respective voxel to generate three-dimensional Z maps. CT scans of individual subjects were evaluated by a computer program for brain atrophy. Voxel-based covariance analysis was performed on standardized images with ages and atrophy indices as independent variables. RESULTS: Inaccuracy assessed by functional data was 2.3%. The maximum anatomical variability was 4.9 mm after standardization. Z maps showed significantly decreased regional CBF (rCBF) in the frontal, parietal and temporal regions in the patient group (P < 0.001). Covariance analysis revealed that the effects of aging on rCBF were more pronounced compared with atrophy, especially in intact cortical areas at an early stage of AD. Decrease in rCBF was partly due to senility and atrophy, however these two factors cannot explain all the deficits. CONCLUSION: AIR can transform SPECT images of AD patients with acceptable accuracy without any need for corresponding structural images. The frontal regions of the brain, in addition to parietal and temporal lobes, may show reduced CBF in patients with AD even at an early stage of dementia. The reduced rCBF in the cortical regions cannot be explained entirely by advanced atrophy and fast aging process.  (+info)

Nitric oxide modulates endothelin 1-induced Ca2+ mobilization and cytoskeletal F-actin filaments in human cerebromicrovascular endothelial cells. (4/8163)

A functional interrelation between nitric oxide (NO), the endothelial-derived vasodilating factor, and endothelin 1 (ET-1), the potent vasoconstrictive peptide, was investigated in microvascular endothelium of human brain. Nor-1 dose-dependently decreased the ET-1-stimulated mobilization of Ca2+. This response was mimicked with cGMP and abrogated by inhibitors of guanylyl cyclase or cGMP-dependent protein kinase G. These findings indicate that NO and ET-1 interactions involved in modulation of intracellular Ca2+ are mediated by cGMP/protein kinase G. In addition, Nor-1-mediated effects were associated with rearrangements of cytoskeleton F-actin filaments. The results suggest mechanisms by which NO-ET-1 interactions may contribute to regulation of microvascular function.  (+info)

Expression of neuropeptide Y receptors mRNA and protein in human brain vessels and cerebromicrovascular cells in culture. (5/8163)

Neuropeptide Y (NPY) has been suggested as an important regulator of CBF. However, except for the presence of Y1 receptors in large cerebral arteries, little is known about its possible sites of action on brain vessels. In this study, we sought to identify the NPY receptors present in the human cerebrovascular bed. Specific Y1 receptor binding sites, localized on the smooth muscle of human pial vessels and potently competed by NPY, polypeptide YY (PYY), and the selective Y1 receptor antagonist BIBP 3226, were identified by quantitative radioautography of the Y1 radioligand [125I]-[Leu31, Pro34]-PYY. In contrast, no specific binding of the Y2-([125I]-PYY3-36) and Y4/Y5-(125I-human pancreatic polypeptide [hPP]) radioligands could be detected. By in situ hybridization, expression of Y1 receptor mRNA was restricted to the smooth muscle layer of pial vessels, whereas no specific signals were detected for either Y2, Y4, or Y5 receptors. Similarly, using reverse transcriptase-polymerase chain reaction (RT-PCR), mRNA for Y1 but not Y2, Y4, or Y5 receptors was consistently detected in isolated human pial vessels, intracortical microvessels, and capillaries. In human brain microvascular cells in culture, PCR products for the Y1 receptors were exclusively found in the smooth muscle cells. In cultures of human brain astrocytes, a cell type that associates intimately with brain microvessels, PCR products for Y1, Y2, and Y4 but not Y5 receptors were identified. Finally, NPY significantly inhibited the forskolin-induced cAMP production in smooth muscle but not in endothelial cell cultures. We conclude that smooth muscle Y1 receptors are the primary if not exclusive NPY receptors associated with human brain extraparenchymal and intraparenchymal blood vessels, where they most likely mediate cerebral vasoconstriction.  (+info)

Disrupted temporal lobe connections in semantic dementia. (6/8163)

Semantic dementia refers to the variant of frontotemporal dementia in which there is progressive semantic deterioration and anomia in the face of relative preservation of other language and cognitive functions. Structural imaging and SPECT studies of such patients have suggested that the site of damage, and by inference the region critical to semantic processing, is the anterolateral temporal lobe, especially on the left. Recent functional imaging studies of normal participants have revealed a network of areas involved in semantic tasks. The present study used PET to examine the consequences of focal damage to the anterolateral temporal cortex for the operation of this semantic network. We measured PET activation associated with a semantic decision task relative to a visual decision task in four patients with semantic dementia compared with six age-matched normal controls. Normals activated a network of regions consistent with previous studies. The patients activated some areas consistently with the normals, including some regions of significant atrophy, but showed substantially reduced activity particularly in the left posterior inferior temporal gyrus (iTG) (Brodmann area 37/19). Voxel-based morphometry, used to identify the regions of structural deficit, revealed significant anterolateral temporal atrophy (especially on the left), but no significant structural damage to the posterior inferior temporal lobe. Other evidence suggests that the left posterior iTG is critically involved in lexical-phonological retrieval: the lack of activation here is consistent with the observation that these patients are all anomic. We conclude that changes in activity in regions distant from the patients' structural damage support the argument that their prominent anomia is due to disrupted temporal lobe connections.  (+info)

The cerebral haemodynamics of music perception. A transcranial Doppler sonography study. (7/8163)

The perception of music has been investigated by several neurophysiological and neuroimaging methods. Results from these studies suggest a right hemisphere dominance for non-musicians and a possible left hemisphere dominance for musicians. However, inconsistent results have been obtained, and not all variables have been controlled by the different methods. We performed a study with functional transcranial Doppler sonography (fTCD) of the middle cerebral artery to evaluate changes in cerebral blood flow velocity (CBFV) during different periods of music perception. Twenty-four healthy right-handed subjects were enrolled and examined during rest and during listening to periods of music with predominant language, rhythm and harmony content. The gender, musical experience and mode of listening of the subjects were chosen as independent factors; the type of music was included as the variable in repeated measurements. We observed a significant increase of CBFV in the right hemisphere in non-musicians during harmony perception but not during rhythm perception; this effect was more pronounced in females. Language perception was lateralized to the left hemisphere in all subject groups. Musicians showed increased CBFV values in the left hemisphere which were independent of the type of stimulus, and background listeners showed increased CBFV values during harmony perception in the right hemisphere which were independent of their musical experience. The time taken to reach the peak of CBFV was significantly longer in non-musicians when compared with musicians during rhythm and harmony perception. Pulse rates were significantly decreased in non-musicians during harmony perception, probably due to a specific relaxation effect in this subgroup. The resistance index did not show any significant differences, suggesting only regional changes of small resistance vessels but not of large arteries. Our fTCD study confirms previous findings of right hemisphere lateralization for harmony perception in non-musicians. In addition, we showed that this effect is more pronounced in female subjects and in background listeners and that the lateralization is delayed in non-musicians compared with musicians for the perception of rhythm and harmony stimuli. Our data suggest that musicians and non-musicians have different strategies to lateralize musical stimuli, with a delayed but marked right hemisphere lateralization during harmony perception in non-musicians and an attentive mode of listening contributing to a left hemisphere lateralization in musicians.  (+info)

Correlation of regional cerebral blood flow and change of plasma sodium concentration during genesis and satiation of thirst. (8/8163)

Positron emission tomography studies were conducted during genesis of moderate thirst by rapid i.v. infusion of hypertonic saline (0.51 M) and after satiation of thirst by drinking water. The correlation of regional cerebral blood flow with the change in the plasma Na concentration showed a significant group of cerebral activations in the anterior cingulate region and also a site in the middle temporal gyrus and in the periaqueductal gray. Strongest deactivations occurred in the parahippocampal and frontal gyri. The data are consistent with an important role of the anterior cingulate in the genesis of thirst.  (+info)

Temporal lobe seizure interhemispheric propagation time depends on nonepileptic cortical cerebral blood flow<...Temporal lobe seizure interhemispheric propagation time depends on nonepileptic cortical cerebral blood flow<...
TY - JOUR. T1 - Temporal lobe seizure interhemispheric propagation time depends on nonepileptic cortical cerebral blood flow. AU - Weinand, M. E.. AU - Labiner, D. M.. AU - Ahern, G. L.. PY - 2001/3/24. Y1 - 2001/3/24. N2 - In some patients with epilepsy, activation of eloquent cortex using various forms of environmental stimulation and mental activity may induce seizures. The increased neuronal activity resulting from cortical stimulation may be associated with increased regional cerebral blood flow. The vascular steal theory of temporal lobe epilepsy suggests that as nonepileptogenic cortical cerebral blood flow (CBFn) increases, temporal lobe epileptogenicity increases as a result, in part, of decreasing interhemispheric propagation time (IHPT). Recently, IHPT has been shown to be a quantitative electrocorticographic measure of temporal lobe epileptogenicity. In the current study, long-term combined subdural-EEG and surface cortical cerebral blood flow (CBF) monitoring was performed to test ...
The influence of hypoglycaemia on regional cerebral blood flow and cerebral volume in type 1 (insulin-dependent) diabetes...The influence of hypoglycaemia on regional cerebral blood flow and cerebral volume in type 1 (insulin-dependent) diabetes...
article{3b545620-2f5d-4405-9964-2753884aaa8d, abstract = {The effect of moderate hypoglycaemia (venous blood glucose 2.0 +/- 0.2 mmol/l; mean +/- SD) on regional cerebral blood flow and cerebral volume was studied in a group of ten right-handed patients with Type 1 (insulin-dependent) diabetes mellitus (age 26.0 +/- 2.4 years, duration 18.4 +/- 3.8 years) using an intravenous Xenon 133 single photon emission computed tomography technique. After 10 min of hypoglycaemia, global cerebral blood flow had increased to 55.8 +/- 4.5 ml.100 g-1.min-1 compared to the initial normoglycaemic flow of 49.5 +/- 3.7 ml.100 g-1.min-1 (p < 0.01). A further increase in global cerebral blood flow to 59.5 +/- 4.5 ml.100 g-1.min-1 (p < 0.05) occurred 15 min after normalization of the blood glucose level. The global cerebral blood flow change from before hypoglycaemia to after recovery was inversely related to the initial glucose level. No change in the relative distribution of the regional cerebral blood flow ...
Effects of Visual Deprivation on Regional Cerebral Blood Flow Velocity and Neurovascular Coupling | JOV | ARVO JournalsEffects of Visual Deprivation on Regional Cerebral Blood Flow Velocity and Neurovascular Coupling | JOV | ARVO Journals
Recently, short-term visual deprivation has been shown to affect a variety of non-visual processes and regional cortical activity (Sathian & Zangaladze, 2001). Surprisingly, very little is known about how such visual deprivation impacts regional cerebral blood flow velocity (CBFv) or its adaptation with the underlying neuronal activity (i.e., neurovascular coupling). The current study sought to investigate the effects of short-term (two-hour) visual deprivation on regional CBFv and neurovascular coupling. CBFv (transcranial Doppler ultrasound) was measured concurrently in the posterior cerebral artery (PCA) and the middle cerebral artery (MCA). Neurovascular coupling was assessed using established methods, consisting of two minutes of baseline (eyes closed and reading), five cycles of 40 seconds reading - 20 seconds eyes-closed (primary protocol), and five cycles of 40 seconds eyes-moving - 20 seconds eyes-closed (secondary protocol). Neurovascular coupling, using both protocols, was collected ...
Lack of effect of antenatal indomethacin on fetal cerebral blood flow<...Lack of effect of antenatal indomethacin on fetal cerebral blood flow<...
TY - JOUR. T1 - Lack of effect of antenatal indomethacin on fetal cerebral blood flow. AU - Parilla, B. V.. AU - Tamura, R. K.. AU - Cohen, L. S.. AU - Clark, E.. AU - Hess, L. W.. AU - Rightmire, D. A.. AU - Saade, G.. PY - 1997/1/1. Y1 - 1997/1/1. N2 - OBJECTIVE: Our purpose was to investigate fetal cerebral blood flow and the incidence of intraventricular hemorrhage in patients undergoing tocolysis with either indomethacin or magnesium sulfate at ,30 weeks gestation. STUDY DESIGN: Consenting patients at ,30 weeks gestation with preterm labor were randomized to receive indomethacin or magnesium sulfate tocolysis. Magnesium sulfate was administered intravenously with an 8 gm loading dose given over the first hour, 4 gm over the second hour, and then a maintenance infusion of 2.5 gm per hour. The infusion was continued for approximately 12 hours after the cessation of uterine contractions. Patients randomized to receive indomethacin were given an initial dose of 50 to 100 mg orally or per ...
REGIONAL CEREBRAL BLOOD FLOW FOLLOWING RESUSCITATION FROM HEMORRHAGIC SHOCK IN DOGS WITH A SUBDURAL MASS | Anesthesiology | ASA...REGIONAL CEREBRAL BLOOD FLOW FOLLOWING RESUSCITATION FROM HEMORRHAGIC SHOCK IN DOGS WITH A SUBDURAL MASS | Anesthesiology | ASA...
J. M. Whitley, D. S. Prough, A. K. Lamb, D. D. Deal, D. S. DeWitt; REGIONAL CEREBRAL BLOOD FLOW FOLLOWING RESUSCITATION FROM HEMORRHAGIC SHOCK IN DOGS WITH A SUBDURAL MASS. Anesthesiology 1988;69(3A):A539. Download citation file:. ...
RWJMS - Departments and Institutes - Physiology and BiophysicsRWJMS - Departments and Institutes - Physiology and Biophysics
Chi, O.Z., C. Hunter, X. Liu, S.K. Chokshi and H.R. Weiss. Effects of fentanyl pretreatment on regional cerebral blood flow in focal cerebral ischemia in rats. Pharmacol. 85:153-157, 2010.. Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss. The effects of isoflurane pretreatment on cerebral blood flow, capillary permeability, and oxygen consumption in focal cerebral ischemia in rats. Anesth. Analg. 110:1412-1418, 2010.. Liu, X., C. Hunter, H.R. Weiss and O.Z. Chi. Effects of blockade of ionotropic glutamate receptors on blood-brain barrier disruption in focal cerebral ischemia. Neurol. Sci. 31:699-703, 2010.. Chi, O.Z., C. Hunter, X. Liu, Y. Chi and H.R. Weiss. Effects of GABAA receptor blockade on regional cerebral blood flow and blood-brain barrier disruption in focal cerebral ischemia. J. Neurol. Sci. 301:66-70, 2011.. Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss. The effects of dexmedetomidine on regional cerebral blood flow and oxygen consumption during severe hemorrhagic hypotension in rats. ...
Cerebral blood flow autoregulation is impaired in schizophrenia: A pilot study<...Cerebral blood flow autoregulation is impaired in schizophrenia: A pilot study<...
TY - JOUR. T1 - Cerebral blood flow autoregulation is impaired in schizophrenia. T2 - A pilot study. AU - Ku, Hsiao Lun. AU - Wang, Jiunn Kae. AU - Lee, Hsin-Chien. AU - Lane, Timothy Joseph. AU - Liu, I-Chao. AU - Chen, Yung Chan. AU - Lee, Yao Tung. AU - Lin, I Cheng. AU - Lin, Chia Pei. AU - Hu, Chaur-Jong. AU - Chi, Nai-Fang. PY - 2017/10. Y1 - 2017/10. N2 - Patients with schizophrenia have a higher risk of cardiovascular diseases and higher mortality from them than does the general population; however, the underlying mechanism remains unclear. Impaired cerebral autoregulation is associated with cerebrovascular diseases and their mortality. Increased or decreased cerebral blood flow in different brain regions has been reported in patients with schizophrenia, which implies impaired cerebral autoregulation. This study investigated the cerebral autoregulation in 21 patients with schizophrenia and 23 age- and sex-matched healthy controls. None of the participants had a history of cardiovascular ...
Arterial spin labeling imaging reveals widespread and Aβ-independent reductions in cerebral blood flow in elderly...Arterial spin labeling imaging reveals widespread and Aβ-independent reductions in cerebral blood flow in elderly...
Changes in cerebral blood flow are an essential feature of Alzheimers disease and have been linked to apolipoprotein E-genotype and cerebral amyloid-deposition. These factors could be interdependent or influence cerebral blood flow via different mechanisms. We examined apolipoprotein E-genotype, amyloid beta-deposition, and cerebral blood flow in amnestic mild cognitive impairment using pseudo-continuous arterial spin labeling MRI in 27 cognitively normal elderly and 16 amnestic mild cognitive impairment participants. Subjects underwent Pittsburgh Compound B (PiB) positron emission tomography and apolipoprotein E-genotyping. Global cerebral blood flow was lower in apolipoprotein E ɛ4-allele carriers (apolipoprotein E4+) than in apolipoprotein E4- across all subjects (including cognitively normal participants) and within the group of cognitively normal elderly. Global cerebral blood flow was lower in subjects with mild cognitive impairment compared with cognitively normal. Subjects with ...
Frontiers | Glutamate Levels and Resting Cerebral Blood Flow in Anterior Cingulate Cortex Are Associated at Rest and...Frontiers | Glutamate Levels and Resting Cerebral Blood Flow in Anterior Cingulate Cortex Are Associated at Rest and...
Progressive loss of brain tissue is seen in some patients with schizophrenia and might be caused by increased levels of glutamate and resting cerebral blood flow (rCBF) alterations. Animal studies suggest that normalization of glutamate levels decreases rCBF and prevents structural changes in hippocampus. However, the relationship between glutamate and rCBF in anterior cingulate cortex (ACC) of humans has not been studied in the absence of antipsychotics and illness chronicity. Ketamine is a non-competitive N-Methyl-D-Aspartate receptor antagonist that transiently induces schizophrenia-like symptoms and neurobiological disturbances in healthy volunteers (HV). Here, we used S-ketamine challenge to assess if glutamate levels were associated with rCBF in anterior cingulate cortex (ACC) in 25 male HV. Second, we explored if S-ketamine changed neural activity as reflected by rCBF alterations in thalamus and accumbens that are connected with ACC. Glutamatergic metabolites were measured in ACC with magnetic
Cerebrovascular circulation: Definition with Cerebrovascular circulation Pictures and PhotosCerebrovascular circulation: Definition with Cerebrovascular circulation Pictures and Photos
Definition of Cerebrovascular circulation with photos and pictures, translations, sample usage, and additional links for more information.
Cerebral blood flow and neuropsychological asymmetries in unilateral stroke. | StrokeCerebral blood flow and neuropsychological asymmetries in unilateral stroke. | Stroke
This study sought to determine the degree of agreement between asymmetries of neuropsychological functioning and nine methods of quantifying asymmetries of regional cerebral blood flow.. The regional cerebral blood flow methods combined three markers of cerebral blood flow asymmetry (percent hemispheric difference, maximum percent probe-pair asymmetry, and number of probe-pair asymmetries) with three indexes of regional cerebral blood flow (fast compartment flow, initial slope index, and initial slope). Eleven patients with left hemispheric ischemic strokes and 13 with right hemispheric ischemic strokes were studied with the xenon-133 inhalation technique and neuropsychological tests.. Blind clinical judgments of neuropsychological asymmetry significantly correlated with all nine methods of cerebral blood flow asymmetry determination; correlations ranged from -0.42 to -0.77. Clinical judgment of asymmetry of neuropsychological functioning accurately predicted the hemisphere of lower flow in ...
Frontotemporal cerebral blood flow change during executive and declarative memory tasks in schizophrenia: A positron emission...Frontotemporal cerebral blood flow change during executive and declarative memory tasks in schizophrenia: A positron emission...
TY - JOUR. T1 - Frontotemporal cerebral blood flow change during executive and declarative memory tasks in schizophrenia. T2 - A positron emission tomography study. AU - Ragland, John D. AU - Gur, Ruben C.. AU - Glahn, David C.. AU - Censits, David M.. AU - Smith, Robin J.. AU - Lazarev, Mark G.. AU - Alavi, Abass. AU - Gur, Raquel E.. PY - 1998/7. Y1 - 1998/7. N2 - Schizophrenia affects prefrontal and temporal-limbic networks. These regions were examined by contrasting regional cerebral blood flow (rCBF) during executive (Wisconsin Card Sorting Test [WCST]), and declarative memory tasks (Paired Associate Recognition Test [PART]). The tasks, and a resting baseline, were administered to 15 patients with schizophrenia and 15 healthy controls during 10 min positron emission tomography 15O-water measures of rCBF. Patients were worse on both tasks. Controls activated inferior frontal, occipitotemporal, and temporal pole regions for both tasks. Similar results were obtained for controls matched to ...
Gray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humansGray matter blood flow change is unevenly distributed during moderate isocapnic hypoxia in humans
Hypoxia increases cerebral blood flow (CBF), but it is unknown whether this increase is uniform across all brain regions. We used H215O positron emission tomography imaging to measure absolute blood flow in 50 regions of interest across the human brain (n = 5) during normoxia and moderate hypoxia. PCO2 was kept constant (44 Torr) throughout the study to avoid decreases in CBF associated with the hypocapnia that normally occurs with hypoxia. Breathing was controlled by mechanical ventilation. During hypoxia (inspired PO2 = 70 Torr), mean end-tidal PO2 fell to 45 ᠶ.3 Torr (means ᠓D). Mean global CBF increased from normoxic levels of 0.39 ᠰ.13 to 0.45 ᠰ.13 ml/g during hypoxia. Increases in regional CBF were not uniform and ranged from 9.9 ᠸ.6% in the occipital lobe to 28.9 ᠱ0.3% in the nucleus accumbens. Regions of interest that were better perfused during normoxia generally showed a greater regional CBF response. Phylogenetically older regions of the brain tended to show larger ...
Different cerebral hemodynamic responses between sexes and various vessels in orthostatic stress tests<...Different cerebral hemodynamic responses between sexes and various vessels in orthostatic stress tests<...
TY - JOUR. T1 - Different cerebral hemodynamic responses between sexes and various vessels in orthostatic stress tests. AU - Wang, Yuh Jen. AU - Chao, A. Ching. AU - Chung, Chih Ping. AU - Huang, Ying Ju. AU - Hu, Han Hwa. PY - 2010/9/1. Y1 - 2010/9/1. N2 - Objective: The argument about why the head-up tilt table test (HUT) does not include the posterior cerebral circulation, which is mainly responsible for syncope, as a monitor target has not been resolved. It is also unclear whether there is a sex difference in cerebral blood flow (CBF) changes. We hypothesized that orthostatic CBF changes more in the posterior circulation than in the anterior circulation and is different between sexes. Methods: Thirty healthy volunteers (13 female and 17 male) were recruited for the HUT. The blood pressure (BP), middle cerebral artery flow velocity (MCAFV), and posterior cerebral artery flow velocity (PCAFV) were monitored simultaneously. Static cerebral autoregulation (CA) was calculated. Results: The female ...
Regional Differences in β-Adrenergic Effects on Local Cerebral Blood Flow and Adrenergic Innervation | SpringerLinkRegional Differences in β-Adrenergic Effects on Local Cerebral Blood Flow and Adrenergic Innervation | SpringerLink
Although it is now well documented (6, 8) that pial as well as intracerebral vessels are amply supplied with sympathetic adrenergic nerves which, as shown for pial arteries, fulfill ultra-structural...
Cerebral Blood FlowCerebral Blood Flow
Four major, interdependent mechanisms are involved in the control of cerebral blood flow: metabolic coupling: neural control, involving both extrinsic and intrinsic neural pathways: Pco2 and autoregulation. Although this division may be somewhat artificial and these control mechanisms probably operate in concert, it is useful to consider each separately. Metabolic Control Local cerebral blood flow (CBF) is regionally heterogeneous. The varied pattern of CBF is neither random nor related to the anatomic organization of the cerebral vasculature or to known differences in the innervation patterns of the cerebral vessels. Neuronal activity is the principal energy-consuming process in the brain. Local cerebral blood flow adjusts to the level of energy generation; therefore, it is the activity in the neuronal circuits that is the major determinant of variations and regional patterns of cerebral blood flow. Normally there is exquisite coupling between the regional cerebral metabolic demand for oxygen ...
Effects of Pentobarbital and Isoflurane on Regional Cerebral Oxygen Extraction and Consumption with Middle Cerebral Artery...Effects of Pentobarbital and Isoflurane on Regional Cerebral Oxygen Extraction and Consumption with Middle Cerebral Artery...
Oak Za Chi, Hwu Meei Wei, Dorene A. OHara, Arabinda K. Sinha, Harvey R. Weiss; Effects of Pentobarbital and Isoflurane on Regional Cerebral Oxygen Extraction and Consumption with Middle Cerebral Artery Occlusion in Rats. Anesthesiology 1993;79(2):299-305. Download citation file:. ...
30: CEREBRAL BLOOD FLOW AND CEREBRAL OXYGEN METABOLISM IN NORMAL AGING: A PRECURSOR FOR STUDY OF DEMENTIA AND ALZHEIMERS...30: CEREBRAL BLOOD FLOW AND CEREBRAL OXYGEN METABOLISM IN NORMAL AGING: A PRECURSOR FOR STUDY OF DEMENTIA AND ALZHEIMER'S...
Background and aims: Aging brain has been demonstrated to be the main risk factor for dementia and Alzheimers disease (AD). Recent findings provide clear evidence that the structural and functional integrity of the brain depends on the delicate balance between substrate delivery through blood flow and energy demands imposed by neural activity. Imaging studies of aging have in general shown reductions of cerebral blood flow (CBF) and the cerebral metabolic rates of oxygen (CMRO2) in healthy elderly adults. Based on the existing evidence, we hypothesized the CBF and CMRO2 in healthy young subjects will be higher than CBF and CMRO2 in elderly adults which itself should be higher than AD patients. Therefore, we designed the present studies specifically to reveal the role of defective cerebral oxygen metabolism and cerebral blood flow in normal aging. ...
Nitric oxide synthase inhibition alters cerebral blood flow and oxygen balance in focal cerebral ischemia in rats. | StrokeNitric oxide synthase inhibition alters cerebral blood flow and oxygen balance in focal cerebral ischemia in rats. | Stroke
This study investigated whether the nitric oxide synthase inhibitor NG-nitro-L-arginine-methyl ester (L-NAME) would alter blood flow and oxygen balance in the ischemic cerebrocortex of isoflurane-anesthetized Long-Evans rats.. Fifteen minutes after middle cerebral artery occlusion, L-NAME (1.5 mg/min per kilogram) was infused intravenously to the L-NAME group (n = 14), and normal saline was given to the control group (n = 14) for 45 minutes. In each group, regional cerebral blood flow was determined with [14C]iodoantipyrine, and arterial and venous oxygen saturations were determined by microspectrophotometry.. In both groups regional cerebral blood flow of the ischemic cortex was significantly lower than that of the contralateral cortex ([mean +/- SD] 55 +/- 13 versus 110 +/- 29 mL/min per 100 g in the control group and 35 +/- 13 versus 90 +/- 24 mL/min per 100 g in the L-NAME group). Compared with the blood flow in the ischemic cortex of the control group, L-NAME significantly reduced ischemic ...
Factors Influencing Cerebral Blood Flow and Metabolism | CirculationFactors Influencing Cerebral Blood Flow and Metabolism | Circulation
The results of studies utilizing the nitrous oxide technic for measuring cerebral blood flow have been reviewed and divided into three groups: (1) those in which cerebral blood flow and metabolism were normal, (2) those in which cerebral blood flow was increased, and (3) those in which cerebral blood flow and metabolism were decreased. The factors which apparently regulate and control cerebral blood flow and metabolism are reviewed and discussed.. ...
Theoretical Basis of Hemodynamic MR Imaging Techniques to Measure Cerebral Blood Volume, Cerebral Blood Flow, and Permeability ...Theoretical Basis of Hemodynamic MR Imaging Techniques to Measure Cerebral Blood Volume, Cerebral Blood Flow, and Permeability ...
3) with the assumption that the large and small vessel Hcts are equal.12. Strictly, recirculation effects should be recognized and removed from the curves. In reality, unless there is significant BBB permeability or areas of very low flow, recirculation effects may be ignored and actually lead to improved estimates of plasma volume that are less sensitive to contrast agent delivery rates (ie, CBF). In low-flow regions, if the tracer does not complete its first passage within the time given for the measurement (usually about 25-30 seconds), it will be undercounted and vp will be underestimated. Because of this result, some authors writing about ischemia have used the term "perfused CBV".13 This may account for the discrepancies seen in between PWI and C15O PET estimates of CBV in ischemia.14 In fact, in the extreme, one would prefer to image as late after injection as possible; when the contrast agent concentration is changing slowly, it more closely approximates a steady-state or "blood pool" ...
Contribution of arterial Windkessel in low-frequency cerebral hemodynamics during transient changes in blood pressure - TeesRep...Contribution of arterial Windkessel in low-frequency cerebral hemodynamics during transient changes in blood pressure - TeesRep...
The Windkessel properties of the vasculature are known to play a significant role in buffering arterial pulsations, but their potential importance in dampening low-frequency fluctuations in cerebral blood flow has not been clearly examined. In this study, we quantitatively assessed the contribution of arterial Windkessel (peripheral compliance and resistance) in the dynamic cerebral blood flow response to relatively large and acute changes in blood pressure. Middle cerebral artery flow velocity (MCA(V); transcranial Doppler) and arterial blood pressure were recorded from 14 healthy subjects. Low-pass-filtered pressure-flow responses (,0.15 Hz) during transient hypertension (intravenous phenylephrine) and hypotension (intravenous sodium nitroprusside) were fitted to a two-element Windkessel model. The Windkessel model was found to provide a superior goodness of fit to the MCA(V) responses during both hypertension and hypotension (R² = 0.89 ± 0.03 and 0.85 ± 0.05, respectively), with a ...
Aging and recognition memory: changes in regional cerebral blood flow associated with components of reaction time distributions...Aging and recognition memory: changes in regional cerebral blood flow associated with components of reaction time distributions...
We used H(2)15O positron emission tomography (PET) to measure age-related changes in regional cerebral blood flow (rCBF) during a verbal recognition memory task. Twelve young adults (20 to 29 years) and 12 older adults (62 to 79 years) participated. Separate PET scans were conducted during Encoding, Baseline, and Retrieval conditions. Each of the conditions involved viewing a series of 64 words and making a two-choice response manually. The complete reaction time (RT) distributions in each task condition were characterized in terms of an ex-Gaussian model (convolution of exponential and Gaussian functions). Parameter estimates were obtained for the mean of the exponential component (tau), representing a task-specific decision process and the mean of the Gaussian component (mu) representing residual sensory coding and response processes. Independently of age group, both tau and mu were higher in the Encoding and Retrieval conditions than in the Baseline condition, and tau was higher during ...
Anesthetic Gases: Organ System Effects | Anesthesiology Core Review: Part One Basic Exam | AccessAnesthesiology | McGraw-Hill...Anesthetic Gases: Organ System Effects | Anesthesiology Core Review: Part One Basic Exam | AccessAnesthesiology | McGraw-Hill...
All inhaled anesthetics increase cerebral blood flow and decrease cerebral metabolic rate for oxygen (CMRO2). Nitrous oxide, however, will increase CMRO2. Nitrous oxide, as well as inhaled anesthetics, causes cerebral vasodilation. However, if the patients blood pressure drops, the increase in cerebral blood flow will be attenuated or abolished because volatile anesthetics inhibit autoregulation. Isoflurane causes the least cerebral vasodilation, maintaining autoregulation better than other volatile anesthetics. Isoflurane also has no effect on cerebrospinal fluid (CSF) production and decreases resistance to CSF absorption. Desflurane increases CSF production without significantly effecting CSF reabsorption. ...
Focal cerebral blood flow change during craving for alcohol measured by SPECT. - Semantic ScholarFocal cerebral blood flow change during craving for alcohol measured by SPECT. - Semantic Scholar
To test the hypothesis that craving for alcohol in the alcohol-dependent individual is mediated by a limbic circuit involving the caudate nuclei, regional cerebral blood flow was measured with [99mTc]HMPAO SPECT during control and craving conditions in 9 alcohol-dependent subjects. In all subjects, blood flow in the head of the right caudate nucleus increased during the craving condition, and these blood flow increases were strongly correlated with the experimentally induced increases in craving for alcohol. These new findings suggest a functional role for the limbic striatum in the mediation of craving and impaired control over alcohol consumption.
Quantification of cerebral blood flow, cerebral blood volume, and blood-brain-barrier leakage with DCE-MRIQuantification of cerebral blood flow, cerebral blood volume, and blood-brain-barrier leakage with DCE-MRI
Dynamic susceptibility contrast MRI (DSC-MRI) is the current standard for the measurement of Cerebral Blood Flow (CBF) and Cerebral Blood Volume (CBV), but it is not suitable for the measurement of Extraction Flow (EF) and may not allow for absolute quantification. The objective of this study was to …
Small vessel disease is associated with altered cerebrovascular pulsatility but not resting cerebral blood flow. - PubMed -...Small vessel disease is associated with altered cerebrovascular pulsatility but not resting cerebral blood flow. - PubMed -...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Effects of exercise therapy on metabolic risk factors, brain atrophy and cerebral blood flow following stroke: A randomised...Effects of exercise therapy on metabolic risk factors, brain atrophy and cerebral blood flow following stroke: A randomised...
Author(s): Moore S, Hallsworth K, Jakovljevic D, Blamire A, He J, Ford G, Rochester L, Trenell M. Publication type: Conference Proceedings (inc. Abstract). Publication status: Published. Conference Name: UK Stroke Forum 2014. Year of Conference: 2014. Pages: 32-32. Print publication date: 01/11/2014. Online publication date: 01/12/2014. ISSN: 1747-4930. Publisher: Wiley-Blackwell Publishing Asia. URL: http://dx.doi.org/10.1111/ijs.12374_12. DOI: 10.1111/ijs.12374_12. Notes: 072. Series Title: International Journal of Stroke. ...
Serval - Regional cerebral blood flow in depression measured by positron emission tomography: the relationship with clinical...Serval - Regional cerebral blood flow in depression measured by positron emission tomography: the relationship with clinical...
We have previously reported focal abnormalities of regional cerebral blood flow (rCBF) in a group of 33 patients with major depression. This report, on an extended sample of 40 patients who demonstrated identical regional deficits to those previously described, examines the relationships between depressive symptoms and patterns of rCBF. Patients symptom ratings were subjected to factor analysis, producing a three-factor solution. The scores for these three factors, which corresponded to recognizable dimensions of depressive illness, were then correlated with rCBF. The first factor had high loadings for anxiety and correlated positively with rCBF in the posterior cingulate cortex and inferior parietal lobule bilaterally. The second factor had high loadings for psychomotor retardation and depressed mood and correlated negatively with rCBF in the left dorsolateral prefrontal cortex and left angular gyrus. The third factor had a high loading for cognitive performance and correlated positi
A Study to Assess Regional Cerebral Blood Flow as an Alzheimer's Disease Biomarker Compared to Positron Emission...A Study to Assess Regional Cerebral Blood Flow as an Alzheimer's Disease Biomarker Compared to Positron Emission...
The aim of the study is to determine if regional cerebral blood flow, measured by dynamic arterial spin labeling (dASL), can be a biomarker for stage of Alzheimers disease. The study is designed to be conducted in 2 parts in participants with mild to moderate Alzheimers disease, and participants with normal cognition. Various imaging studies will be done using magnetic resonance imaging (MRI) and positron emission tomography (PET) along with neurocognitive assessments. Participants who meet the study-entry criteria will have up to 8 study visits. Repeat imaging studies may be required if the initial data are incomplete or un-interpretable. The maximum number of PET scans during the study will be limited to four ...
A Study to Assess Regional Cerebral Blood Flow as an Alzheimer's Disease Biomarker Compared to Positron Emission...A Study to Assess Regional Cerebral Blood Flow as an Alzheimer's Disease Biomarker Compared to Positron Emission...
The aim of the study is to determine if regional cerebral blood flow, measured by dynamic arterial spin labeling (dASL), can be a biomarker for stage of Alzheimers disease. The study is designed to be conducted in 2 parts in participants with mild to moderate Alzheimers disease, and participants with normal cognition. Various imaging studies will be done using magnetic resonance imaging (MRI) and positron emission tomography (PET) along with neurocognitive assessments. Participants who meet the study-entry criteria will have up to 8 study visits. Repeat imaging studies may be required if the initial data are incomplete or un-interpretable. The maximum number of PET scans during the study will be limited to four ...
Cholinergic stimulation alters performance and task-specific regional cerebral blood flow during working memory - IMT...Cholinergic stimulation alters performance and task-specific regional cerebral blood flow during working memory - IMT...
Modulation of the cholinergic neurotransmitter system results in changes in memory performance, including working memory (WM), in animals and in patients with Alzheimer disease. To identify associated changes in the functional brain response, we studied performance measures and regional cerebral blood flow (rCBF) using positron emission tomography (PET) in healthy subjects during performance of a WM task. Eight control subjects received an infusion of saline throughout the study and 13 experimental subjects received a saline infusion for the first 2 scans followed by a continuous infusion of physostigmine, an acetylcholinesterase inhibitor, for the subsequent 8 scans. rCBF was measured using H215O and PET in a sequence of 10 PET scans that alternated between rest and task scans. During task scans, subjects performed the WM task for faces. Physostigmine both improved WM efficiency, as indicated by faster reaction times, and reduced WM task-related activity in anterior and posterior regions of ...
Pooling data from different populations: should there be regional differences in cerebral haemodynamics? | BMC Neurology | Full...Pooling data from different populations: should there be regional differences in cerebral haemodynamics? | BMC Neurology | Full...
Though genetic and environmental determinants of systemic haemodynamic have been reported, surprisingly little is known about their influences on cerebral haemodynamics. We assessed the potential geographical effect on cerebral haemodynamics by comparing the individual differences in cerebral blood flow velocity (CBFv), vasomotor tone (critical closing pressure- CrCP), vascular bed resistance (resistance-area product- RAP) and cerebral autoregulation (CA) mechanism on healthy subjects and acute ischaemic stroke (AIS) patients from two countries. Participants were pooled from databases in Leicester, United Kingdom (LEI) and São Paulo, Brazil (SP) research centres. Stroke patients admitted within 48 h of ischaemic stroke onset, as well as age- and sex-matched controls were enrolled. Beat-to-beat blood pressure (BP) and bilateral mean CBFv were recorded during 5 min baseline. CrCP and RAP were calculated. CA was quantified using transfer function analysis (TFA) of spontaneous oscillations in arterial BP
Pooling data from different populations: should there be regional differences in cerebral haemodynamics? | BMC Neurology | Full...Pooling data from different populations: should there be regional differences in cerebral haemodynamics? | BMC Neurology | Full...
Though genetic and environmental determinants of systemic haemodynamic have been reported, surprisingly little is known about their influences on cerebral haemodynamics. We assessed the potential geographical effect on cerebral haemodynamics by comparing the individual differences in cerebral blood flow velocity (CBFv), vasomotor tone (critical closing pressure- CrCP), vascular bed resistance (resistance-area product- RAP) and cerebral autoregulation (CA) mechanism on healthy subjects and acute ischaemic stroke (AIS) patients from two countries. Participants were pooled from databases in Leicester, United Kingdom (LEI) and São Paulo, Brazil (SP) research centres. Stroke patients admitted within 48 h of ischaemic stroke onset, as well as age- and sex-matched controls were enrolled. Beat-to-beat blood pressure (BP) and bilateral mean CBFv were recorded during 5 min baseline. CrCP and RAP were calculated. CA was quantified using transfer function analysis (TFA) of spontaneous oscillations in arterial BP
Fibromyalgia (FM) in women. Abnormalities of regional cerebral blood flow in the thalamus & the caudate nucleus are associated...Fibromyalgia (FM) in women. Abnormalities of regional cerebral blood flow in the thalamus & the caudate nucleus are associated...
The goal of this study was to determine if regional cerebral blood flow (rCBF)in the left and right hemithalami or the left and right heads of the cau
Opioids and the prostanoid system in the control of cerebral blood flow in hypotensive piglets<...Opioids and the prostanoid system in the control of cerebral blood flow in hypotensive piglets<...
TY - JOUR. T1 - Opioids and the prostanoid system in the control of cerebral blood flow in hypotensive piglets. AU - Armstead, W. M.. AU - Mirro, R.. AU - Busija, D. W.. AU - Leffler, Charles. PY - 1991/1/1. Y1 - 1991/1/1. N2 - The interaction between opioid and prostanoid mechanisms in the control of cerebral hemodynamics was investigated in the conscious hypotensive piglet. Radiomicrospheres were used to determine regional cerebral blood flow (rCBF) in piglets pretreated with the opioid receptor antagonist, naloxone, or its vehicle, saline, during normotension, hypotension, and after the administration of indomethacin, a cyclooxygenase inhibitor, during hypotension. Hemorrhage (30 ml/kg) decreased systemic arterial pressure from 68 ± 12 to 40 ± 10 mm Hg but did not decrease blood flow to any brain region. Indomethacin treatment (5 mg/kg) of hypotensive piglets decreased blood flow to all brain regions within 20 min; this decrease blood flow to all brain regions within 20 rebral vascular ...
Impaired sympathetic regulation of cerebral blood flow in patients with cirrhosis of the liver | Clinical Science | Portland...Impaired sympathetic regulation of cerebral blood flow in patients with cirrhosis of the liver | Clinical Science | Portland...
Continuous recording of mean cerebral blood flow velocity (MCBFV) by Doppler ultrasound allows detection of low-frequency (LF) oscillations, which reflect sympathetic activity in the cerebral circulation. To establish whether the sympathetic drive to the cerebral circulation is altered in patients with compensated cirrhosis, and, if so, where alterations take place, LF oscillations of MCBFV, heart rate (RR interval) and systolic arterial pressure (SAP) were analysed in 10 patients with cirrhosis and 10 control subjects during supine rest and on stimulation of carotid baroreceptors using a neck chamber applying sinusoidal suction. Bivariate analysis was used to study the relationship between pairs of oscillations. In the case of a significant association, the delay in the appearance of the oscillation in MCBFV, SAP and RR was calculated. Baroreceptor stimulation induced significant increases in SAP LF and RR LF power in both groups, while MCBFV LF power increased only in controls. During ...
White matter lesions after occlusion of the bilateral carotid arteries in the rat -temporal profile of cerebral blood flow (CBF...White matter lesions after occlusion of the bilateral carotid arteries in the rat -temporal profile of cerebral blood flow (CBF...
TY - JOUR. T1 - White matter lesions after occlusion of the bilateral carotid arteries in the rat -temporal profile of cerebral blood flow (CBF), oligodendroglia and myelin. AU - Tomimoto, Hidekazu. AU - Akiguchi, Ichiro. AU - Wakita, Hideaki. AU - Kimura, Jun. PY - 1997/12/1. Y1 - 1997/12/1. N2 - In the present investigation, we examined cerebral blood flow (CBF), numerical density of oligodendroRlia and extent of white matter lesions after bilateral libation of common carotid arteries in Wistar rats, Doppler flow meter re\ealed a reduction of CBF to 30-40, of that before operation after 1 and 3 days, however recovered to ,10 60 ‰, after 7 and 14 days, Semiquantitative evaluation with immuohistochemistry for transferrin showed a numerical decrease of oligodendroglia in the medial corpus callosum after 14 and !i() clays, Tissue rarefaction promptly occurred in the optic nerve and optic tract after ,, days, whereas it was- delayed to 7 clays after operation and increased in intensity ...
What is Cerebral Perfusion Pressure? | EP Wellness & Functional Medicine ClinicWhat is Cerebral Perfusion Pressure? | EP Wellness & Functional Medicine Clinic
In the article, cerebral perfusion pressure, or CPP, is the net pressure gradient which affects cerebral blood flow to the brain, known as brain perfusion.
Cerebrovascular Disease Pathophysiology - Clinical FeaturesCerebrovascular Disease Pathophysiology - Clinical Features
Standard techniques of cerebral blood flow (CBF) measurement provide information on both global and regional flow in patients with cerebral ischaemia or infarction. Recent availability of positron emission tomography (PET), recording oxygen and glucose metabolism, as well as blood flow and blood volume, gives a more detailed and accurate understanding of pathophysiological changes after stroke.. Changes in cerebral infarction. NON-ISCHAEMIC HEMISPHERE. Mild reduction in global CBF - perhaps due to transneuronal depression of metabolism in the unaffected hemisphere - diaschisis.. In the normal brain, cerebral blood flow to a particular part varies depending on the metabolic requirements, i.e. the supply of 02 and glucose is coupled to the tissue needs. After infarction, between areas of reduced flow and areas of luxury perfusion, lie areas of relative luxury perfusion where reduced flow exceeds the tissue requirements, i.e. uncoupling of flow and metabolism has occurred.. Studies with SPECT ...
Optical Monitoring of Cerebral Blood Flow at Bedside for Individualized Stroke CareOptical Monitoring of Cerebral Blood Flow at Bedside for Individualized Stroke Care
The effects of positioning of head of bed positioning on blood flow reaching the brain can now be monitored non-invasively and continuously using a new device designed by University of Pennsylvania.
Effects of Adenylate Cyclase, Guanylate Cyclase and KATP Channel Blockade on the Cerebral Blood Flow Response Induced by...Effects of Adenylate Cyclase, Guanylate Cyclase and KATP Channel Blockade on the Cerebral Blood Flow Response Induced by...
This study was performed to investigate the regulatory mechanism of cerebral blood flow of adenosine A $_{2B}$ receptor agonist in the rats, and to define whether its mechanism is mediated by adenylate cyclase, guanylate cyclase and potassium channel. In pentobarbital-anesthetized, pancuronium-par...
Research at The Department of Anaesthesiology Abdominal CentreResearch at The Department of Anaesthesiology Abdominal Centre
Cerebral blood flow and metabolism have been evaluated during exercise to elicit robust "activation" compared with during anaesthesia. It is demonstrated that physical exercise requires an approximately 20 % increase in cerebral blood flow and metabolic rate for oxygen. This reflects that low intensity exercise is associated with increasing cerebral oxygenation, while cerebral oxygenation decreases during maximal exercise, since marked hyperventilation reduces arterial carbon dioxide tension and therefore cerebral blood flow at the same time as the metabolic rate for oxygen is elevated ...
Plus itPlus it
Type 2 diabetes exerts complex effects on cerebral microvasculature that may alter cerebral blood flow regulation. We found a decrease of mean BFV and an increase of CVR in type 2 diabetic patients during baseline, hypocapnia, and hypercapnia. Baseline mean BFV was negatively associated with periventricular WMH grade and volume on T2-weighted images and with A1C and inflammation markers. WMHs were also linked with uncontrolled diabetes, elevated CVR, and impaired CO2 reactivity. The relationship between WMH, uncontrolled diabetes and reduced BFV is of clinical relevance as a potential mechanism for cerebrovascular disease in elderly with type 2 diabetes.. Aging is associated with brain atrophy, changes in frontal subcortical white matter, and executive cognitive dysfunction (9). The CO2 reactivity diminishes with age, uncontrolled diabetes, and risk factors for atherosclerosis (22). In community-living elderly people, blood flow in the WMHs was lower compared with normal-appearing white matter ...
Adventures in the Pathophysiology of Brain Ischemia: Penumbra, Gene Expression, Neuroprotection: The 2002 Thomas Willis Lecture...Adventures in the Pathophysiology of Brain Ischemia: Penumbra, Gene Expression, Neuroprotection: The 2002 Thomas Willis Lecture...
BACKGROUND: The pathophysiology of cerebral ischemia is well studied in small-animal models, which offer reproducibility and control of confounding variables-factors essential to hypothesis-testing. This presentation first highlights insights into the ischemic penumbra enabled by a multimodal experimental approach; second, discusses gene expression in ischemia; and third, confronts the challenges of neuroprotectant therapy. Summary of Review- The ischemic penumbra: Transient (2-hour) middle cerebral artery suture-occlusion in anesthetized rats gives rise to highly consistent neurological and histopathological sequelae. Autoradiographic local cerebral blood flow (LCBF) studies at 2 hours of occlusion define the penumbra as a region of intermediate CBF depression (20% to 40% of control) surrounding the densely ischemic core (5% to 20% of control) and constituting one half of the entire lesion. Local glucose metabolic rate in the acute penumbra is not reduced despite the critical CBF reduction, so ...
Evaluation of cerebral blood flow changes in ischemia rats by using doppler ultrasound | PolyU Institutional Research ArchiveEvaluation of cerebral blood flow changes in ischemia rats by using doppler ultrasound | PolyU Institutional Research Archive
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Blood Pressure Changes | Noninvasive ICPBlood Pressure Changes | Noninvasive ICP
Authors: Feldstein CA.. Epidemiological studies suggest an association between chronic blood pressure (BP) changes and Alzheimers disease (AD). In particular, there is growing evidence that hypertensive people that do not have their BP adequately treated and controlled in midlife are more likely to develop AD in late-life. It has been hypothesized that cerebrovascular disease is a common pathway which connects hypertension and AD in individuals with apolipoprotein E genotype through brain hypoperfusion and hypoxia. This could accelerate amyloid-β aggregation that disrupts cell-to-cell connectivity and leads to eventual brain neuron loss. Also, high BP contributes to worsen AD by raising oxidative stress and inflammatory response. Aging-related structural and functional disturbances appear to exacerbate the deleterious effect of chronic hypertension on cerebral blood flow autoregulation. There is evidence suggesting that some antihypertensive drug classes reduce the risk and progression of AD ...
Phenylephrine increases cerebral blood flow during low-flow hypothermic cardiopulmonary bypass in baboons<...Phenylephrine increases cerebral blood flow during low-flow hypothermic cardiopulmonary bypass in baboons<...
TY - JOUR. T1 - Phenylephrine increases cerebral blood flow during low-flow hypothermic cardiopulmonary bypass in baboons. AU - Schwariz, Arthur E.. AU - Minanov, Oktavijan. AU - Stone, J. Gilbert. AU - Adams, David C.. AU - Sandhu, Aqeel A.. AU - Pearson, Mark E.. AU - Kwiatkowski, Pawel. AU - Young, William L.. AU - Michler, Robert E.. PY - 1996/8/23. Y1 - 1996/8/23. N2 - Background: Although low-flow cardiopulmonary bypass (CPB) has become a preferred technique for the surgical repair of complex cardiac lesions in children, the relative hypotension and decrease in cerebral blood flow (CBF) associated with low flow may contribute to the occurrence of postoperative neurologic injury. Therefore, it was determined whether phenylephrine administered to increase arterial blood pressure during low-flow CPB increases CBF. Methods: Cardiopulmonary bypass was initiated in seven baboons during fentanyl, midazolam, and isoflurane anesthesia. Animals were cooled at a pump flow rate of 2.5 1 · min -1 · m ...
Cognitive function and dynamic cerebral blood flow regulation in multiple concussions<...Cognitive function and dynamic cerebral blood flow regulation in multiple concussions<...
TY - JOUR. T1 - Cognitive function and dynamic cerebral blood flow regulation in multiple concussions. AU - Kumazaki, Akira. AU - Ogoh, Shigehiko. AU - Hirasawa, Ai. AU - Sakai, Sadayoshi. AU - Hirose, Norikazu. PY - 2018/3. Y1 - 2018/3. N2 - Background: Concussion causes acute, short-term brain dysfunctions. However, the impact of repetitive concussion history on brain function remains unclear. Objectives: The present study examined the effect of a history of multiple concussions on the cognitive functions and dynamic cerebral blood flow (CBF) regulation in collegiate rugby football players. Methods: Nine male rugby football players with a history of≤1 concussion and nine players with a history of multiple concussions (≤ 4 concussions) participated in this study. Reaction time and working memory were assessed using a neurocognitive assessment device (CogSport; CogState Ltd., Melbourne, Australia). Arterial blood pressure and middle cerebral artery blood velocity (MCAv) were measured ...
Effect of stimulation of carotid chemoreceptors on total and regional cerebral blood flow. | Circulation ResearchEffect of stimulation of carotid chemoreceptors on total and regional cerebral blood flow. | Circulation Research
This study was performed to determine whether stimulation of the carotid chemoreceptors increases total or regional cerebral blood flow and whether activation of arterial chemoreceptors contributes to cerebral vasodilation during systemic hypoxemia. In anesthetized and ventilated dogs, carotid chemoreceptors were stimulated with nicotine or hypoxic and hypercapnic blood. To measure total and regional cerebral blood flow, we used labeled 15-mu microspheres. Stimulation of chemoreceptors did not increase cerebral blood flow or produce significant redistribution of cerebral blood flow, even though the chemoreflex was intact in these animals (as manifested by vasoconstriction in muscle, kidney, and small bowel) and the cerebral vessels dilated in response to systemic hypercapnia. In other studies in anesthetized, ventilated dogs and rhesus monkeys, cerebral vasodilator responses to systemic hypoxemia were observed before and after denervation of carotid and aortic chemoreceptors. Systemic hypoxemia ...
Low Cerebral Oxygen Consumption and Blood Flow in Patients With Cirrhosis and an Acute Episode of Hepatic Encephalopathy<...Low Cerebral Oxygen Consumption and Blood Flow in Patients With Cirrhosis and an Acute Episode of Hepatic Encephalopathy<...
TY - JOUR. T1 - Low Cerebral Oxygen Consumption and Blood Flow in Patients With Cirrhosis and an Acute Episode of Hepatic Encephalopathy. AU - Iversen, Peter. AU - Sørensen, Michael. AU - Bak, Lasse Kristoffer. AU - Waagepetersen, Helle Sønderby. AU - Vafaee, Manouchehr Seyedi. AU - Borghammer, Per. AU - Mouridsen, Kim. AU - Jensen, Svend Borup. AU - Vilstrup, Hendrik. AU - Schousboe, Arne. AU - Ott, Peter. AU - Gjedde, Albert. AU - Keiding, Susanne. PY - 2009/3. Y1 - 2009/3. N2 - Background & Aims: It is unclear whether patients with hepatic encephalopathy (HE) have disturbed brain oxygen metabolism and blood flow. Methods: We measured cerebral oxygen metabolism rate (CMRO2) by using 15O-oxygen positron emission tomography (PET); and cerebral blood flow (CBF) by using 15O-water PET in 6 patients with liver cirrhosis and an acute episode of overt HE, 6 cirrhotic patients without HE, and 7 healthy subjects. Results: Neither whole-brain CMRO2 nor CBF differed significantly between cirrhotic ...
Quantitative Cerebral Blood Flow Measurement with Dynamic Perfusion CT Using the Vascular-Pixel Elimination Method: Comparison...Quantitative Cerebral Blood Flow Measurement with Dynamic Perfusion CT Using the Vascular-Pixel Elimination Method: Comparison...
BACKGROUND AND PURPOSE: Blood vessels are usually conspicuous on dynamic CT perfusion images. The presence of large vessels may lead to overestimation of the quantitative value of cerebral blood flow (CBF). We evaluated the efficacy of the vascular-pixel elimination (VPE) method in quantitative CT perfusion imaging, in comparison with positron emission tomography (PET).. METHODS: Five healthy volunteers underwent CT perfusion and PET studies. A four-channel multi-detector row CT scanner was used. Dynamic cine scanning was performed after bolus injection of an intravenous contrast agent. CT-CBF was calculated by the central volume principle and deconvolution method. PET was performed after infusion of 15O-labeled water. PET-CBF was calculated by using a nonlinear least squares method. Average CBF values of the whole section, gray matter, and white matter with both CT and PET were compared after image registration. The comparison was performed with and without VPE. In the VPE method, the vascular ...
Regional cerebral blood flow during mechanical hyperventilation in patients with fulminant hepatic failureRegional cerebral blood flow during mechanical hyperventilation in patients with fulminant hepatic failure
Hyperventilation is frequently used to prevent or postpone the development of cerebral edema and intracranial hypertension in patients with fulminant hepatic failure (FHF). The influence of such therapy on regional cerebral blood flow (rCBF) remains, however, unknown. In this study the CBF-distribution pattern was determined within the first 12 hours after development of hepatic encephalopathy (HE) stage 4 before and during hyperventilation. Ten consecutive patients (median age 48 [range 33-57] years) with FHF and 9 healthy controls (median age 54 [24-58] years) had rCBF determined by single photon emission computed tomography (SPECT) using intravenous injection of 133Xenon. For determination of high resolution CBF pattern, the patients were also studied with 99mTc-hexa-methylpropyleneamine oxime (HMPAO) in the hyperventilation condition. There was no significant difference in the rCBF distribution pattern during normoventilation as compared with hyperventilation. The anterior to posterior (AP) ...
Distribution of regional cerebral blood flow in voluntarily diving rats. | Journal of Experimental BiologyDistribution of regional cerebral blood flow in voluntarily diving rats. | Journal of Experimental Biology
The distribution of regional cerebral blood flow (rCBF) was examined in conscious, voluntarily diving rats using the brain blood flow tracer N-[14C]isopropyl-p-iodoamphetamine and quantitative autoradiography. A detailed examination of the regional distribution of cerebral blood flow revealed that almost all brain regions were hyperperfused during diving. During diving, rCBF increased by an average of 1.7-fold in 29 of the 33 brain regions examined, despite a 69.2 % decrease in cardiac output. Only some regions of the basal ganglia (caudate-putamen and globus pallidus) and limbic areas (hippocampus and amygdala) did not increase rCBF significantly during diving. We determined that the increase in rCBF during diving is primarily due to a corresponding 20.9 % decrease in cerebrovascular resistance. A significant increase in perfusion pressure during diving also potentially contributed to the increase in rCBF. Because some brain regions did not increase flow significantly during diving, these ...
Raised intracranial pressure and the cerebral circulation - Enlighten: ThesesRaised intracranial pressure and the cerebral circulation - Enlighten: Theses
The first five chapters of the thesis review the literature on intracranial pressure, the cerebral circulation and their interrelation and set the scene for the experimental work which is described in chapters 6 to 11. Intracranial pressure is now measured routinely in many clinical centres but a great deal of caution is required in interpreting the results, particularly with respect to the method of measurement, the history of any raised pressure and the values of other physiological variables such as blood pressure and cerebral blood flow. The cerebral circulation itself displays a remarkable tendency to remain constant, the fundamental concept being that there exists a basic control mechanism which acts to maintain cerebral blood flow in order to meet the metabolic requirements of the brain. The methods used to measure cerebral blood flow in the work described are metabolically inert gas clearance techniques based on the Pick principle. Hemisphere blood flow in baboons was measured by the ...
Cerebral dysfunction in fibromyalgia (FM): evidence from regional cerebral blood flow measurements, otoneurological tests &...Cerebral dysfunction in fibromyalgia (FM): evidence from regional cerebral blood flow measurements, otoneurological tests &...
Measurements of regional cerebral blood flow (rCBF), analysis ofcerebrospinal fluid, auditory brain stem responses (ABR) andoculomotor tests
Quantification of Serial Cerebral Blood Flow in Acute Stroke Using Arterial Spin Labeling. - Nuffield Department of Clinical...Quantification of Serial Cerebral Blood Flow in Acute Stroke Using Arterial Spin Labeling. - Nuffield Department of Clinical...
BACKGROUND AND PURPOSE: Perfusion-weighted imaging is used to select patients with acute ischemic stroke for intervention, but knowledge of cerebral perfusion can also inform the understanding of ischemic injury. Arterial spin labeling allows repeated measurement of absolute cerebral blood flow (CBF) without the need for exogenous contrast. The aim of this study was to explore the relationship between dynamic CBF and tissue outcome in the month after stroke onset. METHODS: Patients with nonlacunar ischemic stroke underwent ≤5 repeated magnetic resonance imaging scans at presentation, 2 hours, 1 day, 1 week, and 1 month. Imaging included vessel-encoded pseudocontinuous arterial spin labeling using multiple postlabeling delays to quantify CBF in gray matter regions of interest. Receiver-operator characteristic curves were used to predict tissue outcome using CBF. Repeatability was assessed in 6 healthy volunteers and compared with contralateral regions of patients. Diffusion-weighted and T2-weighted
Different effects of prenatal MAM vs. perinatal THC exposure on regional cerebral blood perfusion detected by Arterial Spin...Different effects of prenatal MAM vs. perinatal THC exposure on regional cerebral blood perfusion detected by Arterial Spin...
Clinical studies consistently report structural impairments (i.e.: ventricular enlargement, decreased volume of anterior cingulate cortex or hippocampus) and functional abnormalities including changes in regional cerebral blood flow in individuals suffering from schizophrenia, which can be evaluated by magnetic resonance imaging (MRI) techniques. The aim of this study was to assess cerebral blood perfusion in several schizophrenia-related brain regions using Arterial Spin Labelling MRI (ASL MRI, 9.4 T Bruker BioSpec 94/30USR scanner) in rats. In this study, prenatal exposure to methylazoxymethanol acetate (MAM, 22 mg/kg) at gestational day (GD) 17 and the perinatal treatment with Delta-9-tetrahydrocannabinol (THC, 5 mg/kg) from GD15 to postnatal day 9 elicited behavioral deficits consistent with schizophrenia-like phenotype, which is in agreement with the neurodevelopmental hypothesis of schizophrenia. In MAM exposed rats a significant enlargement of lateral ventricles and perfusion changes ...
Neonatal cerebral blood flow velocity responses to changes in posture. | Archives of Disease in ChildhoodNeonatal cerebral blood flow velocity responses to changes in posture. | Archives of Disease in Childhood
Maintaining a constant cerebral blood flow during a change in cerebral perfusion pressure is known as autoregulation. The integrity of this phenomenon is considered to be important in preventing cerebral lesions in preterm infants. A study was carried out using Doppler ultrasound measurements of cerebral blood flow velocities (CBFV) as an indicator of alterations in cerebral haemodynamics. CBFV were recorded on a beat to beat basis over 60 second epochs, during which time the cerebral perfusion pressure was changed by rapidly altering the infants posture from horizontal to either 20 degrees head up or head down. An informative response in CBFV was considered to be either (a) a uniphasic, immediate, passive alteration in velocity occurring with the change in posture and without a subsequent change or (b) a biphasic response of an initial change in CBFV followed within 20 seconds by a second response. This latter response is considered to be consistent with autoregulatory activity. A total of 501 ...
Laser doppler flowmetry to measure changes in cerebral blood flow - Radcliffe Department of MedicineLaser doppler flowmetry to measure changes in cerebral blood flow - Radcliffe Department of Medicine
Laser Doppler flowmetry (LDF) is a method by which relative cerebral blood flow (CBF) of the cortex can be measured. Although the method is easy to employ, LDF only measures relative CBF, while absolute CBF cannot be quantified. LDF is useful for investigating CBF changes in a number of different applications including neurovascular and stroke research. This chapter will prepare the reader for rodent experiments using LDF with two preparations. The closed skull preparation can be used to monitor CBF with an intact skull, but in adult rats, thinning of the skull is required to obtain an accurate cortical CBF signal. The open skull preparation requires a craniotomy to expose the surface of the brain and the LDF probe is held close to the surface to measure cerebral perfusion. © 2014 Springer Science+Business Media New York.
Laser Doppler flowmetry to measure changes in cerebral blood flow. - Radcliffe Department of MedicineLaser Doppler flowmetry to measure changes in cerebral blood flow. - Radcliffe Department of Medicine
Laser Doppler flowmetry (LDF) is a method by which relative cerebral blood flow (CBF) of the cortex can be measured. Although the method is easy to employ, LDF only measures relative CBF, while absolute CBF cannot be quantified. LDF is useful for investigating CBF changes in a number of different applications including neurovascular and stroke research. This chapter will prepare the reader for rodent experiments using LDF with two preparations. The closed skull preparation can be used to monitor CBF with an intact skull, but in adult rats, thinning of the skull is required to obtain an accurate cortical CBF signal. The open skull preparation requires a craniotomy to expose the surface of the brain and the LDF probe is held close to the surface to measure cerebral perfusion.
Cerebral hemodynamic changes after wartime traumatic brain injury<...Cerebral hemodynamic changes after wartime traumatic brain injury<...
TY - GEN. T1 - Cerebral hemodynamic changes after wartime traumatic brain injury. AU - Razumovsky, Alexander. AU - Tigno, Teodoro. AU - Hochheimer, Sven M.. AU - Stephens, Fred L.. AU - Bell, Randy. AU - Vo, Alexander H.. AU - Severson, Meryl A.. AU - Marshall, Scott A.. AU - Oppenheimer, Stephen M.. AU - Ecker, Robert. AU - Armonda, Rocco A.. PY - 2013. Y1 - 2013. N2 - Traumatic brain injury (TBI) is associated with the severest casualties from Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF). From October 1, 2008, the U.S. Army Medical Department initiated a transcranial Doppler (TCD) ultrasound service for TBI; included patients were retrospectively evaluated for TCD-determined incidence of post-traumatic cerebral vasospasm and intracranial hypertension after wartime TBI. Ninety patients were investigated with daily TCD studies and a comprehensive TCD protocol, and published diagnostic criteria for vasospasm and increased intracranial pressure (ICP) were applied. TCD signs ...
Validation of the CBF, CBV, and MTT Values by Perfusion MRI in Chronic Occlusive Cerebrovascular Disease: A Comparison with ...Validation of the CBF, CBV, and MTT Values by Perfusion MRI in Chronic Occlusive Cerebrovascular Disease: A Comparison with ...
TY - JOUR. T1 - Validation of the CBF, CBV, and MTT Values by Perfusion MRI in Chronic Occlusive Cerebrovascular Disease. T2 - A Comparison with 15O-PET. AU - Kaneko, Koichiro. AU - Kuwabara, Yasuo. AU - Mihara, Futoshi. AU - Yoshiura, Takashi. AU - Nakagawa, Makoto. AU - Tanaka, Atsuo. AU - Sasaki, Masayuki. AU - Koga, Hirofumi. AU - Hayashi, Kazutaka. AU - Honda, Hiroshi. PY - 2004/5. Y1 - 2004/5. N2 - Rationale and Objectives. To evaluate the reliability of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) values obtained by deconvolution algorithm perfusion-weighted MR imaging (D-PWI), we compared these values with those obtained by first-moment algorithm perfusion-weighted MR imaging (F-PWI) and 15O-PET. Subjects and Methods. Six healthy volunteers and eleven patients with chronic occlusive cerebrovascular disease were studied with both perfusion-weighted MR imaging and 15O-PET, and region-of-interest analyses were performed. Normalization factors for CBF ...
PDF] Continuous monitoring of regional cerebral blood flow: experimental and clinical validation of a novel thermal diffusion...PDF] Continuous monitoring of regional cerebral blood flow: experimental and clinical validation of a novel thermal diffusion...
OBJECT Current clinical neuromonitoring techniques lack adequate surveillance of cerebral perfusion. In this article, a novel thermal diffusion (TD) microprobe is evaluated for the continuous and quantitative assessment of intraparenchymal regional cerebral blood flow (rCBF). METHODS To characterize the temporal resolution of this new technique, rCBF measured using the TD microprobe (TD-rCBF) was compared with rCBF levels measured by laser Doppler (LD) flowmetry during standardized variations of CBF in a sheep model. For validation of absolute values, the microprobe was implanted subcortically (20 mm below the level of dura) into 16 brain-injured patients, and TD-rCBF was compared with simultaneous rCBF measurements obtained using stable xenon-enhanced computerized tomography scanning (sXe-rCBF). The two techniques were compared using linear regression analysis as well as the Bland and Altman method. Stable TD-rCBF measurements could be obtained throughout all 3- to 5-hour sheep experiments. During
Cerebral blood flow measurements in subarachnoid haemorrhage with an intravenous isotope technique : methodological studies :...Cerebral blood flow measurements in subarachnoid haemorrhage with an intravenous isotope technique : methodological studies :...
Cerebral blood flow measurements in subarachnoid haemorrhage with an intravenous isotope technique: methodological studies : the significance of cerebral blood flow determinations in the timing of surgery of arterial aneurysm ...
Inversion of neurovascular coupling after subarachnoid hemorrhage in vivo - Munich Cluster for Systems Neurology - LMU MunichInversion of neurovascular coupling after subarachnoid hemorrhage in vivo - Munich Cluster for Systems Neurology - LMU Munich
Abstract. Subarachnoid hemorrhage (SAH) induces acute changes in the cerebral microcirculation. Recent findings ex vivo suggest neurovascular coupling (NVC), the process that increases cerebral blood flow upon neuronal activity, is also impaired after SAH. The aim of the current study was to investigate whether this occurs also in vivo. C57BL/6 mice were subjected to either sham surgery or SAH by filament perforation. Twenty-four hours later NVC was tested by forepaw stimulation and CO2 reactivity by inhalation of 10% CO2. Vessel diameter was assessed in vivo by two-photon microscopy. NVC was also investigated ex vivo using brain slices. Cerebral arterioles of sham-operated mice dilated to 130% of baseline upon CO2 inhalation or forepaw stimulation and cerebral blood flow (CBF) increased. Following SAH, however, CO2 reactivity was completely lost and the majority of cerebral arterioles showed paradoxical constriction in vivo and ex vivo resulting in a reduced CBF response. As previous results ...
Repositorio da Producao Cientifica e Intelectual da Unicamp: Elevated thalamic and prefrontal regional cerebral blood flow in...Repositorio da Producao Cientifica e Intelectual da Unicamp: Elevated thalamic and prefrontal regional cerebral blood flow in...
Functional neuroimaging studies have pointed to a possible role of cerebral circuits involving the prefrontal and anterior cingulate cortices, the striatum, and thalamus in the pathophysiology of obsessive-compulsive disorder (OCD). Regional cerebral blood flow (rCBF) of 16 drug-free Brazilian patients with OCD and 17 healthy subjects matched for age, gender, handedness and level of education was measured with [99m-Tc] HMPAO single photon emission computed tomography. Analysis of covariance identified four regions of interest with significantly higher rCBF: the right superior and inferior frontal cortex and the right and left thalamus. Positive correlations between symptom severity measured by Clinical Global Impression scores and rCBF were found in the right and left inferior frontal lobes and in the right basal ganglia. Compulsive behavior was inversely correlated with rCBF in the right thalamus, and duration of illness correlated positively with rCBF in the right and left superior frontal ...
KAKEN - Research Projects | Development of Quantitative Cerebral Blood Flow and Oxygen Metabolism using O-17 Water and Oxygen...KAKEN - Research Projects | Development of Quantitative Cerebral Blood Flow and Oxygen Metabolism using O-17 Water and Oxygen...
Principal Investigator：Kudo Kohsuke, Project Period (FY)：2014-04-01 - 2017-03-31, Research Category：Grant-in-Aid for Scientific Research (B), Section：一般, Research Field：Radiation science
Long term evaluation of brain perfusion with magnetic resonance in high flow extracranial-intracranial saphenous graft bypass<...Long term evaluation of brain perfusion with magnetic resonance in high flow extracranial-intracranial saphenous graft bypass<...
TY - JOUR. T1 - Long term evaluation of brain perfusion with magnetic resonance in high flow extracranial-intracranial saphenous graft bypass. AU - Bozzao, Alessandro. AU - Fasoli, Fabrizio. AU - Finocchi, Vanina. AU - Santoro, Giuseppe. AU - Romano, Andrea. AU - Fantozzi, Luigi Maria. PY - 2007/1. Y1 - 2007/1. N2 - Assessment was made of the cerebral vascular haemodynamic parameters in patients with a high-flow extra-intracranial (EC-IC) bypass performed for therapeutic occlusion of the internal carotid artery (ICA). Sixteen patients with ICA occlusion and EC-IC bypass (time interval from surgery 1-6 years) underwent MRI. Perfusion-weighted magnetic resonance imaging (PW-MRI) sequences were performed without the use of an arterial input function. The relative cerebral blood volume (rCBV), mean transit time (MTT) and relative cerebral blood flow (rCBF) were evaluated in all patients at the level of the basal ganglia, centrum semiovale and cortex in both hemispheres. Statistically significant ...
Brain Blood Flow Modulates the Neurotoxic Action of Hyperbaric Oxygen via Neuronal and Endothelial Nitric Oxide<...Brain Blood Flow Modulates the Neurotoxic Action of Hyperbaric Oxygen via Neuronal and Endothelial Nitric Oxide<...
TY - JOUR. T1 - Brain Blood Flow Modulates the Neurotoxic Action of Hyperbaric Oxygen via Neuronal and Endothelial Nitric Oxide. AU - Moskvin, A. N.. AU - Zhilyaev, S. Yu. AU - Sharapov, O. I.. AU - Platonova, T. F.. AU - Gutsaeva, Diana Raisovna. AU - Kostkin, V. B.. AU - Demchenko, I. T.. PY - 2003/11/1. Y1 - 2003/11/1. N2 - Studies on conscious rats with inhibition of NO synthase were used to assess the dynamics of brain blood flow and EEG traces during hyperbaric oxygenation at 4 or 5 atm. Oxygen at a pressure of 4 atm induced cerebral vasoconstriction in intact animals and decreased blood flow by 11-18% (p , 0.05) during 60-min exposure to hyperbaric oxygenation. Paroxysmal EEG activity and oxygen convulsions did not occur in rats at 4 atm of O2. At 5 atm, convulsive activity appeared on the EEG at 41 ± 1.9 min, and blood flow decreased significantly during the first 20 min; blood flow increased by 23 ± 9%, as compared with controls, (p , 0.01) before the appearance of convulsions on the ...
Dr. Philip Ainslie | ICORDDr. Philip Ainslie | ICORD
Cardiovascular health; cerebral blood flow regulation; cerebrovascular function Dr. Philip Ainslies research is focused on the integrated mechanisms that regulate human cerebral blood flow in health and disease, the influence of environmental stress, and the effects of exercise training on cerebrovascular function.. Dr. Philip Ainslie is a Professor in the School of Health and Exercise Sciences at UBC Okanagan, the Co-Director of the Centre for Heart, Lung & Vascular Health, and an ICORD Investigator. His Ph.D. (in exercise physiology & metabolism) was a collaborative project between the Liverpool John Moores University, University of Manchester and University of Oxford. Following completion of a post-doctoral research fellowship at the University of Calgary he began a faculty position in 2005, as Lecturer and Principal Investigator in the Department of Physiology at the University of Otago, New Zealand. Here, he established his independent research program, focusing on the integrative ...
Effect of backrest position on intracranial pressure and cerebral perfusion pressure in individuals with brain injury: a...Effect of backrest position on intracranial pressure and cerebral perfusion pressure in individuals with brain injury: a...
Free Online Library: Effect of backrest position on intracranial pressure and cerebral perfusion pressure in individuals with brain injury: a systematic review. by Journal of Neuroscience Nursing; Health care industry Brain injuries Care and treatment Primary care nursing Methods Primary nursing
Designing and comparing optimized pseudo-continuous Arterial Spin Labeling protocols for measurement of cerebral blood flow. -...Designing and comparing optimized pseudo-continuous Arterial Spin Labeling protocols for measurement of cerebral blood flow. -...
Arterial Spin Labeling (ASL) is a non-invasive, non-contrast, perfusion imaging technique which is inherently SNR limited. It is, therefore, important to carefully design scan protocols to ensure accurate measurements. Many pseudo-continuous ASL (PCASL) protocol designs have been proposed for measuring cerebral blood flow (CBF), but it has not yet been demonstrated which design offers the most accurate and repeatable CBF measurements. In this study, a wide range of literature PCASL protocols were first optimized for CBF accuracy and then compared using Monte Carlo simulations and in vivo experiments. The protocols included single-delay, sequential and time-encoded multi-timepoint protocols, and several novel protocol designs, which are hybrids of time-encoded and sequential multi-timepoint protocols. It was found that several multi-timepoint protocols produced more confident, accurate, and repeatable CBF estimates than the single-delay protocol, while also generating maps of arterial transit time. Of
When the air hits your brain: Cerebral autoregulation of brain oxygenation during aerobic exercise allows transient...When the air hits your brain: Cerebral autoregulation of brain oxygenation during aerobic exercise allows transient...
TY - JOUR. T1 - When the air hits your brain. T2 - Cerebral autoregulation of brain oxygenation during aerobic exercise allows transient hyperoxygenation: Case report. AU - Bollo, Robert J.. AU - Williams, Susan C.. AU - Peskin, Charles. AU - Samadani, Uzma. PY - 2010/8. Y1 - 2010/8. N2 - OBJECTIVE: Cerebral autoregulation maintains a relatively stable cerebral blood flow over a range of perfusion pressures. During exercise, regional cerebral blood flow may be elevated in particular areas of the brain. This case report presents the impact of aerobic exercise on intracranially measured pressure and brain tissue oxygenation in an adult human. CLINCIAL PRESENTATION: A 30-year-old man with idiopathic intracranial hypertension treated with cerebrospinal fluid diversion was monitored with a Licox intracranial brain oxygen and pressure monitor (Integra NeuroSciences Corporation, Plainsboro, New Jersey) for refractory nonpostural headaches exacerbated after exercise. He performed trials of running and ...
Repositório Institucional UNIFESP: Effects of heart failure on cerebral blood flow in copd: rest and exerciseRepositório Institucional UNIFESP: Effects of heart failure on cerebral blood flow in copd: rest and exercise
Cerebral blood flow (CBF) and oxygenation (COx) are generally well-preserved in COPD. It is unknown whether prevalent cardiovascular co-morbidities, such as heart failure, may impair CBF and COx responses to exertion. Eighteen males with moderate-to-severe COPD (8 with and 10 without overlapping heart failure) underwent a progressive exercise test with pre-frontal CBF and COx measurements (indocyanine green and near-infrared spectroscopy). Mean arterial pressure and cardiac output were lower from rest to exercise in overlap. Only COPD patients demonstrated an increase in arterialized PCO2 towards the end of progressive exercise. CBF index was consistently higher and increased further by similar to 40% during exercise in COPD whereas a similar to 10% reduction was observed in overlap. COx was lower in overlap despite preserved arterial oxygenation. In conclusion, heart failure introduces pronounced negative effects on CBF and COx in COPD which may be associated with clinically relevant outcomes, ...
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The mechanism of action of vinpocetine is composed of several elements: it improves cerebral blood flow and metabolism, has a beneficial effect on the rheological properties of blood. The neuroprotective action is realized by reducing the adverse cytotoxic effect of excitatory amino acids. Improves the exchange of serotonin and norepinephrine in the brain, it stimulates the noradrenergic neurotransmitter systems and has an antioxidant effect. It improves the microcirculation in the brain by inhibiting platelet aggregation, reducing the pathologically increased blood viscosity, increase the deformability of red blood cells and the inhibition of the reuptake of adenoeina; promotes oxygen transfer into the cells by reducing the affinity of erythrocytes thereto. Selectively increases cerebral blood flow by reducing the cerebral vascular resistance without a significant impact on system performance circulatory (blood pressure (BP), cardiac output, heart rate, total peripheral vascular resistance); It ...
Clarient Diagnostics has licensed cancer biomarker; NASA-sponsored bone test could spot osteoporosis and cancer; | FierceBiotechClarient Diagnostics has licensed cancer biomarker; NASA-sponsored bone test could spot osteoporosis and cancer; | FierceBiotech
| Arterial spin labeling (ASL) MRI, which measures cerebral blood flow, could act as a biomarker in Alzheimers disease. Abstract | GE Healthcare ($GE) company Clarient Diagnostic Services...
Dynamic pressure - Flow relationship of the cerebral circulation during acute increase in arterial pressure<...Dynamic pressure - Flow relationship of the cerebral circulation during acute increase in arterial pressure<...
TY - JOUR. T1 - Dynamic pressure - Flow relationship of the cerebral circulation during acute increase in arterial pressure. AU - Zhang, Rong. AU - Behbehani, Khosrow. AU - Levine, Benjamin D.. PY - 2009. Y1 - 2009. N2 - The physiological mechanism(s) for the regulation of the dynamic pressure-flow relationship of the cerebral circulation are not well understood. We studied the effects of acute cerebral vasoconstriction on the transfer function between spontaneous changes in blood pressure (BP) and cerebral blood flow velocity (CBFV) in 13 healthy subjects (30 ± 7 years). CBFV was measured in the middle cerebral artery using transcranial Doppler. BP was increased stepwise with phenylephrine infusion at 0.5, 1.0 and 2.0 μg kg-1 min-1. Phenylephrine increased BP by 11, 23 and 37% from baseline, while CBFV increased (11%) only with the highest increase in BP. Cerebrovascular resistance index (BP/CBFV) increased progressively by 6, 17 and 23%, demonstrating effective steady-state autoregulation. ...
Endothelial influences on cerebrovascular tone<...Endothelial influences on cerebrovascular tone<...
TY - JOUR. T1 - Endothelial influences on cerebrovascular tone. AU - Andresen, Jon. AU - Shafi, Nadeem. AU - Bryan, Robert M.. PY - 2006/1/1. Y1 - 2006/1/1. N2 - The cerebrovascular endothelium exerts a profound influence on cerebral vessels and cerebral blood flow. This review summarizes current knowledge of various dilator and constrictor mechanisms intrinsic to the cerebrovascular endothelium. The endothelium contributes to the resting tone of cerebral arteries and arterioles by tonically releasing nitric oxide (NO • ). Dilations can occur by stimulated release of NO • , endothelium-derived hyperpolarization factor, or prostanoids. During pathological conditions, the dilator influence of the endothelium can turn to that of constriction by a variety of mechanisms, including decreased NO • bioavailability and release of endothelin-1. The endothelium may participate in neurovascular coupling by conducting local dilations to upstream arteries. Further study of the cerebrovascular ...
The longitudinal changes of BOLD response and cerebral hemodynamics from acute to subacute stroke. A fMRI and TCD study | BMC...The longitudinal changes of BOLD response and cerebral hemodynamics from acute to subacute stroke. A fMRI and TCD study | BMC...
By mapping the dynamics of brain reorganization, functional magnetic resonance imaging MRI (fMRI) has allowed for significant progress in understanding cerebral plasticity phenomena after a stroke. However, cerebro-vascular diseases can affect blood oxygen level dependent (BOLD) signal. Cerebral autoregulation is a primary function of cerebral hemodynamics, which allows to maintain a relatively constant blood flow despite changes in arterial blood pressure and perfusion pressure. Cerebral autoregulation is reported to become less effective in the early phases post-stroke. This study investigated whether any impairment of cerebral hemodynamics that occurs during the acute and the subacute phases of ischemic stroke is related to changes in BOLD response. We enrolled six aphasic patients affected by acute stroke. All patients underwent a Transcranial Doppler to assess cerebral autoregulation (Mx index) and fMRI to evaluate the amplitude and the peak latency (time to peak-TTP) of BOLD response in the acute
Autoregulation of cerebral blood flow in hypertensive patients. The modifying influence of prolonged antihypertensive treatment...Autoregulation of cerebral blood flow in hypertensive patients. The modifying influence of prolonged antihypertensive treatment...
Autoregulation of cerebral blood flow (CBF) was studied by the arteriovenous oxygen difference method in 13 patients with untreated or ineffectively treated severe hypertension, nine patients with effectively treated, formerly severe hypertension, and ten normotensive controls. Resting mean blood pressure in these three groups was 145 +/- 17 (1 SD) mm Hg, 116 +/- 18 mm Hg, and 98 +/- 10 mm Hg, respectively. Blood pressure was decreased by trimethaphan infusion combined with head-up tilt. The lower limit of CBF autoregulation in the three groups was 113 +/- 17 mm Hg, 96 +/- 17 mm Hg, and 73 +/- 9 mm Hg, and the lowest tolerated blood pressure where mild symptoms of brain hypoperfusion were encountered was 65 +/- 10 mm Hg, 53 +/- 18 mm Hg, and 43 +/- 8 mm Hg. These pressures were all significantly higher (P less than 0.01) in the group of untreated or ineffectively treated hypertensive patients than in the normotensive group demonstrating a shift of CBF autoregulation in the former. The ...
Regional Cerebral Blood Flow and Response to Carbon Dioxide during Controlled Hypotension with Isoflurane Anesthesia in the RatRegional Cerebral Blood Flow and Response to Carbon Dioxide during Controlled Hypotension with Isoflurane Anesthesia in the Rat
Regional (frontal, parietal, occipital, cortical, and basal ganglia) cerebral blood flow (rCBF) was examined at 1.5 and 3.5 MAC inspired isoflurane/O2 anesthesia in the rat using the radioactive microsphere technique to determine the effects of controlled hypotension with deep isoflurane anesthesia
BOLD Functional MRI and Cognitive Aging : Cognitive Neuroscience of Aging - oiBOLD Functional MRI and Cognitive Aging : Cognitive Neuroscience of Aging - oi
This chapter focuses on potential confounding factors in the interpretation of the blood oxygen level dependent (BOLD) signal in fMRI studies of cognitive aging. Studies generally attribute age-related changes in BOLD signal to age-related changes in neural activity, thereby assuming that the coupling between BOLD signal and neural activity is the same for young and older adults. However, this coupling may be altered by age-related changes in the neurovascular system and by comorbidities associated with aging. Age-related changes of the neurovascular system likely to affect the BOLD signal include changes in ultrastructure (e.g., sclerosis), resting cerebral blood flow (CBF), vascular reactivity, and cerebral metabolic rate of oxygen consumption. The BOLD signal may also be affected by comorbidities associated with aging, such as leukoariosis and small strokes, and by medications. ...
iLab Publications - University of Southern CaliforniaiLab Publications - University of Southern California
A. H. Craig, J. L. Cummings, L. A. Fairbanks, L. Itti, B. L. Miller, J. Li, I. Mena, Cerebral blood flow correlates of apathy in Alzheimer disease, Archives of Neurology, Vol. 53, No. 11, pp. 1116-20, Nov 1996. [1998 impact factor: 3.375] (Cited by 231). Abstract: BACKGROUND: Apathy is a pervasive noncognitive neuropsychiatric disturbance in Alzheimer disease, which causes significant caregiver distress. The neuroanatomical substrate of apathy is not well understood. OBJECTIVE: To study the relationship between regional cerebral blood flow and the presence and severity of the personality disturbance, apathy, in individuals with Alzheimer disease. DESIGN: Analysis of the relationship between regional cerebral blood flow as measured by single photon emission computed tomography and severity of apathy as measured by the Neuropsychiatric Inventory using an analysis of variance design. We examined regional cerebral perfusion alterations as measured by xenon 133Xecalibrated technetium Tc 99m ...
CT perfusion cerebral blood flow imaging in neurological critical careCT perfusion cerebral blood flow imaging in neurological critical care
Computed tomography (CT) perfusion imaging is a technique for the measurement of cerebral blood flow, cerebral blood volume, and time-to-peak or mean transit time. The technique involves the administration of a single-bolus dose of iodinated contrast material, followed by spiral CT imaging during the passage of the contrast bolus through the cerebral vasculature. CT perfusion is a fast and inexpensive brain imaging modality for use in the management of patients with various neurological disorders, ranging from acute stroke to subarachnoid hemorrhage. This article reviews the technique of CT perfusion and presents several illustrative cases in which this imaging modality was used effectively in the critical care of patients with neurological disorders. Copyright © 2005 Humana Press Inc. All rights of any nature whatsoever are reserved ...
Best Cerebral Vascular Disease Doctor in Delhi NCR, Cerebral Vascular Disease Doctors | CredihealthBest Cerebral Vascular Disease Doctor in Delhi NCR, Cerebral Vascular Disease Doctors | Credihealth
Find the best cerebral vascular disease doctors in Delhi NCR. Get guidance from medical experts to select cerebral vascular disease specialist in Delhi NCR from trusted hospitals - credihealth.com
ᐉ Cannabidiol Improves Blood Flow To Brains Hippocampus ᐉ Dispensary Tubeᐉ Cannabidiol Improves Blood Flow To Brain's Hippocampus ᐉ Dispensary Tube
ᐉ Cannabidiol (CBD) increases cerebral blood flow to areas of the brain associated with memory processing, specifically the hippocampus. The findings identify
Gaseous mediatorGaseous mediator
Brain ischemiaBrain ischemia
ICAM-1ICAM-1
List of MeSH codes (G09)List of MeSH codes (G09)
Smoking banSmoking ban
Cerebral organoidCerebral organoid
Center for Cerebrovascular ResearchCenter for Cerebrovascular Research
Complement component 4BComplement component 4B
Cerebrovascular diseaseCerebrovascular disease
Paradoxical embolismParadoxical embolism
Leptomeningeal collateral circulationLeptomeningeal collateral circulation
List of ICD-9 codes 740-759: congenital anomaliesList of ICD-9 codes 740-759: congenital anomalies
American Heart AssociationAmerican Heart Association
Antiplatelet drugAntiplatelet drug
Category:Cerebrovascular diseasesCategory:Cerebrovascular diseases
Health in GuyanaHealth in Guyana
Silent strokeSilent stroke
Orthostatic hypertensionOrthostatic hypertension
Xanthine oxidaseXanthine oxidase
Intracranial aneurysmIntracranial aneurysm
Cytochrome b-245, alpha polypeptideCytochrome b-245, alpha polypeptide
Blood pressureBlood pressure
Cerebral circulationCerebral circulation
Transcranial DopplerTranscranial Doppler
Walter DandyWalter Dandy
AutoregulationAutoregulation
Postperfusion syndromePostperfusion syndrome
Watershed strokeWatershed stroke
Intima-media thicknessIntima-media thickness
ResveratrolResveratrol
Strok bahasa Indonesia, ensiklopedia bebasStrok bahasa Indonesia, ensiklopedia bebas
Leigh syndromeLeigh syndrome
Vertebral artery dissectionVertebral artery dissection
Intracranial aneurysmIntracranial aneurysm
RofecoxibRofecoxib
Intracerebral hemorrhageIntracerebral hemorrhage
Multiple system atrophyMultiple system atrophy
جراحی مغز و اعصاب - ویکی‌پدیا، دانشنامهٔ آزادجراحی مغز و اعصاب - ویکی‌پدیا، دانشنامهٔ آزاد
ಮಾನವನಲ್ಲಿ ರಕ್ತ ಪರಿಚಲನೆ - ವಿಕಿಪೀಡಿಯಮಾನವನಲ್ಲಿ ರಕ್ತ ಪರಿಚಲನೆ - ವಿಕಿಪೀಡಿಯ
Hepatic encephalopathyHepatic encephalopathy
Beta blockerBeta blocker
Prostacyclin receptorProstacyclin receptor
ICD-10 Chapter IX: Diseases of the circulatory systemICD-10 Chapter IX: Diseases of the circulatory system
Pre-eclampsiaPre-eclampsia
PerfusionPerfusion
Accident vascular cerebral - Viquipèdia, lenciclopèdia lliureAccident vascular cerebral - Viquipèdia, l'enciclopèdia lliure
Transient global amnesiaTransient global amnesia
Postural orthostatic tachycardia syndromePostural orthostatic tachycardia syndrome
Arteriopatia perifèrica - Viquipèdia, lenciclopèdia lliureArteriopatia perifèrica - Viquipèdia, l'enciclopèdia lliure
Subarachnoid hemorrhageSubarachnoid hemorrhage
RepinotanRepinotan
Celekoksib - Wikipedija, prosta enciklopedijaCelekoksib - Wikipedija, prosta enciklopedija
ଷ୍ଟ୍ରୋକ - ଉଇକିପିଡ଼ିଆଷ୍ଟ୍ରୋକ - ଉଇକିପିଡ଼ିଆ
Intraventricular hemorrhageIntraventricular hemorrhage
AgeingAgeing
Somatomedina C, a enciclopedia libreSomatomedina C, a enciclopedia libre
AnatomyOrganismsDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPsychiatry and PsychologyPhenomena and ProcessesDisciplines and OccupationsAnthropology, Education, Sociology and Social PhenomenaTechnology, Industry, AgricultureInformation ScienceHealth CareGeographicals
Cerebrovascular CirculationBlood CirculationExtracorporeal CirculationPulmonary CirculationVertebrobasilar InsufficiencyPosterior Cerebral ArteryVertebral ArteryInfarction, Posterior Cerebral ArteryBasilar ArteryCerebral AngiographySyndromeHypoplastic Left Heart SyndromeHeart Defects, CongenitalNorwood ProceduresUmbilical ArteriesFontan ProcedureBlalock-Taussig ProcedureFetusMetabolic Syndrome XGinkgo bilobaHeparan Sulfate ProteoglycansPhotometryPoloxaleneBiological MarkersBlood-Brain BarrierPhotographyAnimal FinsLightBathsSunburnStrokePerfusion ImagingBrain IschemiaBrainContrast MediaPerfusionCerebral InfarctionSoftwareReagent Kits, DiagnosticImage Processing, Computer-AssistedSensitivity and SpecificityReproducibility of ResultsPrivacyConfidentialityComputer SecurityInformed ConsentHearing LossHearingDisease OutbreaksCongresses as TopicSocieties, MedicalPrince Edward IslandEducation, GraduateCardiologyPublishingJapan
Cerebrovascular circulation: Definition with Cerebrovascular circulation Pictures and PhotosCerebrovascular circulation: Definition with Cerebrovascular circulation Pictures and Photos
Posterior circulation cerebrovascular syndromesPosterior circulation cerebrovascular syndromes
Posterior circulation cerebrovascular syndromes: diagnosis and management | Journal of Neurology, Neurosurgery & PsychiatryPosterior circulation cerebrovascular syndromes: diagnosis and management | Journal of Neurology, Neurosurgery & Psychiatry
Cerebrovascular Circulation | Profiles RNSCerebrovascular Circulation | Profiles RNS
Abstract 17236: Comparative Analysis of Cerebrovascular Resistance in the Fetus with Single Ventricle Type of Congenital Heart...Abstract 17236: Comparative Analysis of Cerebrovascular Resistance in the Fetus with Single Ventricle Type of Congenital Heart...
Abstract 033: Cardio-Cerebro-Vascular Diseases: Prevention in Metabolic Syndrome Patients | Circulation ResearchAbstract 033: Cardio-Cerebro-Vascular Diseases: Prevention in Metabolic Syndrome Patients | Circulation Research
Cerebrovascular geometry in the anterior circulation: an analysis of diameter, length and the vessel taper | Journal of...Cerebrovascular geometry in the anterior circulation: an analysis of diameter, length and the vessel taper | Journal of...
Karen G. Hirsch, MD | Stanford Medicine ProfilesKaren G. Hirsch, MD | Stanford Medicine Profiles
White matter thresholds for ischemic penumbra and infarct core in patients with acute stroke: CT perfusion studyWhite matter thresholds for ischemic penumbra and infarct core in patients with acute stroke: CT perfusion study
Anesthesiology Research LabAnesthesiology Research Lab
Differences in CT perfusion maps generated by different commercial software: quantitative analysis by using identical source...Differences in CT perfusion maps generated by different commercial software: quantitative analysis by using identical source...
May-June 1985 - Volume 6 - Issue 3 : Ear and HearingMay-June 1985 - Volume 6 - Issue 3 : Ear and Hearing
A model of the cerebral and cerebrospinal fluid circulations to examine asymmetry in cerebrovascular reactivity. - Oxford...A model of the cerebral and cerebrospinal fluid circulations to examine asymmetry in cerebrovascular reactivity. - Oxford...
Model-based Indices Describing Cerebrovascular Dynamics | SpringerLinkModel-based Indices Describing Cerebrovascular Dynamics | SpringerLink
American Heart Association - AHA - healthfinder.govAmerican Heart Association - AHA - healthfinder.gov
Desflurane Versus Propofol in the Sitting Position - Full Text View - ClinicalTrials.govDesflurane Versus Propofol in the Sitting Position - Full Text View - ClinicalTrials.gov
The 84th Annual Scientific Meeting of the Japanese Circulation SocietyThe 84th Annual Scientific Meeting of the Japanese Circulation Society
Study illuminates fMRI interpretation - RedorbitStudy illuminates fMRI interpretation - Redorbit
Plus itPlus it
Buy low level laser therapy equipment - low level laser therapy equipment on saleBuy low level laser therapy equipment - low level laser therapy equipment on sale
Tryptophan?Tryptophan?
Dynamic cerebral autoregulation is impaired in glaucoma.Dynamic cerebral autoregulation is impaired in glaucoma.
Effects of hypercapnia on brain pHi and phosphate metabolite regulation by 31P-NMR.Effects of hypercapnia on brain pHi and phosphate metabolite regulation by 31P-NMR.
Sensitivity and reliability of cerebral oxygenation responses to postural changes measured with near-infrared spectroscopy |...Sensitivity and reliability of cerebral oxygenation responses to postural changes measured with near-infrared spectroscopy |...
Trends in mortality from cerebro vascular diseases in the usa 1960 1975Trends in mortality from cerebro vascular diseases in the usa 1960 1975
Patente US5379774 - Measurement of arterial elasticity and the frequency characteristic of the ... - Google PatentesPatente US5379774 - Measurement of arterial elasticity and the frequency characteristic of the ... - Google Patentes
慢性脑供血不足患者的脑血管慢性脑供血不足患者的脑血管
Center for Sanse-Motorisk Interaktion - Publikationer - Aalborg Universitets forskningsportalCenter for Sanse-Motorisk Interaktion - Publikationer - Aalborg Universitets forskningsportal
Jaime Grutzendler, MD > Neurology | Yale School of...Jaime Grutzendler, MD > Neurology | Yale School of...
AnatomyOrganismsDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPsychiatry and PsychologyPhenomena and ProcessesDisciplines and OccupationsAnthropology, Education, Sociology and Social PhenomenaTechnology, Industry, AgricultureInformation ScienceHealth CareGeographicals
Cerebrovascular CirculationBlood CirculationExtracorporeal CirculationPulmonary CirculationVertebrobasilar InsufficiencyPosterior Cerebral ArteryVertebral ArteryInfarction, Posterior Cerebral ArteryBasilar ArteryCerebral AngiographySyndromeHypoplastic Left Heart SyndromeHeart Defects, CongenitalNorwood ProceduresUmbilical ArteriesFontan ProcedureBlalock-Taussig ProcedureFetusMetabolic Syndrome XGinkgo bilobaHeparan Sulfate ProteoglycansPhotometryPoloxaleneBiological MarkersBlood-Brain BarrierPhotographyAnimal FinsLightBathsSunburnStrokePerfusion ImagingBrain IschemiaBrainContrast MediaPerfusionCerebral InfarctionSoftwareReagent Kits, DiagnosticImage Processing, Computer-AssistedSensitivity and SpecificityReproducibility of ResultsPrivacyConfidentialityComputer SecurityInformed ConsentHearing LossHearingDisease OutbreaksCongresses as TopicSocieties, MedicalPrince Edward IslandEducation, GraduateCardiologyPublishingJapan
VascularStrokePosterior circulationHumansDiseasesCerebral blooInternal carotiBrain IschemiaVertebrobasilarAcuteInsufficiencyCardiovascularIntravascularAnteriorBloodNeuronalANATOMYClinical FindingsMeSHSymptomsDisordersNerveMeasuring cerebrovascular diseaseDisordersHypertensionAngiographyComputerized tomographyArterialIntracranialHypertensiveReturn of spontaneous circulationCerebral blood circulationNeurologicalAccidentTissueDegenerativeDefineTreatment
Vascular1
  • These data indicate that the removal of prostanoid modulation of an opioid-mediated constrictor influence on the cerebral circulation is a potential mechanism for the increase in cerebral vascular resistance that follows indomethacin treatment of hypotensive piglets. (elsevier.com)
Stroke10
Posterior circulation8
Humans1
  • Although several factors may contribute to CAA in humans, the neuronal origin of transgenic APP, high levels of Aβ in cerebrospinal fluid, and regional localization of CAA in APP23 mice suggest transport and drainage pathways rather than local production or blood uptake of Aβ as a primary mechanism underlying cerebrovascular amyloid formation. (pnas.org)
Diseases7
Cerebral bloo4
Internal caroti1
Brain Ischemia1
Vertebrobasilar1
Acute1
Insufficiency2
Cardiovascular1
Intravascular3
  • Intravascular sonography has been used to assess the outcomes of different percutaneous interventions, including angioplasty and stent implantation, and to provide detailed characterization of atherosclerotic lesions, aneurysms, and dissections within the cerebrovascular circulation. (ajnr.org)
  • Currently there are 3 types of sonography used to assess the extracranial and the intracranial circulation: 1) transcranial Doppler, 2) B-mode sonography, and 3) intravascular sonography ( Table ). (ajnr.org)
  • The morphologic appearance of the intra-arterial and intravenous circulation can now be visualized by using intravascular sonography, which has become a commonly used diagnostic technique for randomized clinical trials assessing coronary plaque progression and regression. (ajnr.org)
Anterior2
Blood6
Neuronal1
  • APP23 mice on an App -null background developed a similar degree of both plaques and CAA, providing further evidence that a neuronal source of APP/Aβ is sufficient to induce cerebrovascular amyloid and associated neurodegeneration. (pnas.org)
ANATOMY1
Clinical Findings1
MeSH1
  • Cerebrovascular Circulation" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (umassmed.edu)
Symptoms1
Disorders1
Nerve1
  • Helping to regulate that circulation are specialized support cells called astrocytes, which are far more numerous than nerve cells. (redorbit.com)
Measuring cerebrovascular disease1
Disorders3
Hypertension3
Angiography2
Computerized tomography1
Arterial5
Intracranial1
Hypertensive3
  • Hypertensive crisis - a factor of the destabilization of cerebral circulation. (neurology-jornal.org)
  • Second, we hypothesized that a down-regulation of functional K v 1 channels contributes to the elevated cerebrovascular tone of hypertensive rats and that this event is associated with a loss of ancillary K v β2 subunits. (proquest.com)
  • Using spontaneously hypertensive rat (SHR) and aortic-banded (Ao-B) rat models, we report that a loss of K v 1 channel dilator function and expression as a result of transcriptional down-regulation of pore-forming α subunit(s) contribute to the elevated cerebrovascular tone in hypertensive rats. (proquest.com)
Return of spontaneous circulation1
  • In this study, we were unable to demonstrate any difference in the overall rate of return of spontaneous circulation, survival to hospital admission, survival to hospital discharge, or neurologic outcome between patients treated with a standard dose of epinephrine and those treated with a high dose. (elsevier.com)
Cerebral blood circulation1
Neurological1
Accident2
Tissue1
  • It can treat gout, improve cerebrovascular circulation, increase phagocyte activity, improve tissue regeneration and help cure wounds. (chinasodiumcarbonate.com)
Degenerative1
Define1
  • This thesis project pursued three hypotheses to define several key processes that influence K v 1 channel function and expression levels in cerebrovascular smooth muscle cells (cVSMCs) of rat. (proquest.com)
Treatment1
  • These findings indicate that PTZ treatment can have prolonged effects on Cerebrovascular functions and neuronal integrity even in the absence of convulsive activity. (elsevier.com)