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Mean cerebral blood flow

Kazuhiro Murayama, Kazuhiro Katada, Motoharu Hayakawa, Hiroshi Toyama
OBJECTIVE: We aimed to clarify the cause of shortened mean transit time (MTT) in acute ischemic cerebrovascular disease and examined its relationship with reperfusion. METHODS: Twenty-three patients with acute ischemic cerebrovascular disease underwent whole-brain computed tomography perfusion (CTP). The maximum MTT (MTTmax), minimum MTT (MTTmin), ratio of maximum and minimum MTT (MTTmin/max), and minimum cerebral blood volume (CBV) (CBVmin) were measured by automatic region of interest analysis...
October 7, 2016: Journal of Computer Assisted Tomography
N H Sperna Weiland, D Breevoord, D A Jöbsis, E M F H de Beaumont, V Evers, B Preckel, M W Hollmann, S van Dieren, B A J M de Mol, R V Immink
Despite a rise in blood pressure, cerebral oxygenation decreases following phenylephrine administration, and we hypothesised that phenylephrine reduces cerebral oxygenation by activating cerebral α1 receptors. We studied patients on cardiopulmonary bypass during constant flow. Phenylephrine raised mean arterial pressure (α1 -mediated) from mean (SD) 69 (8) mmHg to 79 (8) mmHg; p = 0.001, and vasopressin raised mean arterial pressure (V1 mediated) from 69 (8) mmHg to 83 (6) mmHg; p = 0.001. Both drugs elicited a comparable decrease in cerebral oxygenation from 61 (7)% to 60 (7)%; p = 0...
October 17, 2016: Anaesthesia
Laurence Ducharme-Crevier, Michele G Mills, Priya M Mehta, Craig M Smith, Mark S Wainwright
BACKGROUND: The primary objective of this study was to characterize changes in cerebral blood flow measured using transcranial Doppler in children with central nervous system infections. We hypothesized that children with central nervous system infections have abnormal cerebral blood flow, associated with a greater frequency of complications and poor neurological outcome. METHODS: We conducted a single-center, retrospective study of children admitted to the neonatal or pediatric intensive care unit with central nervous system infection and undergoing transcranial Doppler as part of routine care between March 2011 and July 2015...
September 4, 2016: Pediatric Neurology
Mohamed Ghalayini, Pierre-Yves Brun, Pascal Augustin, Elise Guivarch, Marie Pierre Dilly, Sophie Provenchere, Pierre Mordant, Yves Castier, Philippe Montravers, Dan Longrois
Competitive flows syndrome result in severe regional hypoxemia when the deoxygenated flow from the native left ventricle (LV) competes with oxygenated flow from extracorporeal life support (ECLS) pump with potentially severe consequences for the cerebral and coronary circulations. Fast correction of hypoxemia could be obtained by decreasing native LV flow by infusion of a short-acting beta-blocker (esmolol). Our purpose was to retrospectively review the efficacy of esmolol in this situation and hypothesize on the potential mechanisms of action and the associated risks...
September 2016: Journal of Extra-corporeal Technology
Bhawna Gupta, Ali Dodge-Khatami, Juan Tucker, Mary B Taylor, Douglas Maposa, Miguel Urencio, Jorge D Salazar
BACKGROUND: Antegrade cerebral perfusion (ACP) typically is used with deep hypothermia for cerebral protection during aortic arch reconstructions. The impact of ACP on cerebral oxygenation and serum creatinine at a more tepid 25 °C was studied in newborns and children. METHODS: Between 2010 and 2014, 61 newborns and children (<5 years old) underwent aortic arch reconstruction using moderate hypothermia (25.0±0.9 °C) with ACP and a pH-stat blood gas management strategy...
July 2016: Translational pediatrics
Maria Skytioti, Signe Søvik, Maja Elstad
Intact cerebral blood flow (CBF) is essential for cerebral metabolism and function, whereas hypoperfusion in relation to hypovolemia and hypocapnia can lead to severe cerebral damage. This study was designed to assess internal carotid artery blood flow (ICA-BF) during simulated hypovolemia and noninvasive positive pressure ventilation (PPV) in young healthy humans. Beat-by-beat blood velocity (ICA and aorta) were measured by Doppler ultrasound during normovolemia and simulated hypovolemia (lower body negative pressure), with or without PPV in 15 awake subjects...
October 2016: Physiological Reports
Kyle Verdecchia, Mamadou Diop, Albert Lee, Laura B Morrison, Ting-Yim Lee, Keith St Lawrence
Diffuse correlation spectroscopy (DCS) is a promising technique for brain monitoring as it can provide a continuous signal that is directly related to cerebral blood flow (CBF); however, signal contamination from extracerebral tissue can cause flow underestimations. The goal of this study was to investigate whether a multi-layered (ML) model that accounts for light propagation through the different tissue layers could successfully separate scalp and brain flow when applied to DCS data acquired at multiple source-detector distances...
September 1, 2016: Biomedical Optics Express
Koji Yamashita, Akio Hiwatashi, Osamu Togao, Kazufumi Kikuchi, Hiroo Yamaguchi, Yuriko Suzuki, Ryotaro Kamei, Ryo Yamasaki, Jun-Ichi Kira, Hiroshi Honda
PURPOSE: To evaluate cerebral blood flow (CBF) laterality derived from arterial spin labeling (ASL) in early-stage Parkinson's disease (PD) patients compared with those with advanced stages. MATERIALS AND METHODS: Thirty-eight patients with PD (21 patients in early stages, 17 patients in advanced stages) were retrospectively studied. The CBF maps derived from 3T ASL data were co-registered to the corresponding 3DT1WI using SPM 12 software. Caudate nucleus (CN), putamen (PT), globus pallidus (GP), and thalamus (TH) were manually traced on the representative axial slices of 3DT1WI...
October 3, 2016: Journal of Magnetic Resonance Imaging: JMRI
P E Frid, S J Schreiber, O Pade, F Doepp, J Valdueza
PURPOSE: To differentiate PCA segments and cortical branches by means of transcranial color-coded duplex sonography (TCCD) and to measure flow parameters at rest and during visual stimulation. MATERIALS AND METHODS: 60 healthy subjects with a good acoustic temporal bone window were examined. The main stem of the PCA (P1, P2 and P3) and 4 main cortical branches - the anterior temporal artery (ATA), the occipital temporal artery (OTA), the parietooccipital artery (POA) and the calcarine artery (CA) - were assessed using an axial transtemporal approach...
November 2015: Ultrasound Int Open
Y Duan, B Q Yang, C C Chang, J Zhou, H Y Li, Z H Xu, Z W Wang, D Y Li
Objective: To evaluate the level of lexiscan-induced blood-brain barrier opening of healthy rabbits via CT perfusion weighted imaging (PWI) scan. Methods: Between November 2014 and May 2015, thirty New Zealand white rabbits were randomly assigned into three groups: the experimental group A1 which received one injection of lexiscan(1 ml/kg); the experimental group A2 which received three times injection of lexiscan(total dose: 1.5 ml/kg), finished within 15 minutes; the control group B which was injected the same volume normal saline(1 ml/kg), after 30 minutes, CT PWI scan was performed...
September 20, 2016: Zhonghua Yi Xue za Zhi [Chinese medical journal]
R M D'Ortenzio, S P Hojjat, R Vitorino, C G Cantrell, L Lee, A Feinstein, P O'Connor, T J Carroll, R I Aviv
BACKGROUND AND PURPOSE: Quantitative CBF usage as a biomarker for cognitive impairment and disease progression in MS is potentially a powerful tool for longitudinal patient monitoring. Dynamic susceptibility contrast perfusion with bookend T1-calibration (bookend technique) and pseudocontinuous arterial spin-labeling have recently been used for CBF quantification in relapsing-remitting MS. The noninvasive nature of pseudocontinuous arterial spin-labeling is advantageous over gadolinium-based techniques, but correlation between the techniques is not well-established in the context of MS...
September 29, 2016: AJNR. American Journal of Neuroradiology
Misaki Kohama, Shinichiro Sugiyama, Kenichi Sato, Hidenori Endo, Kuniyasu Niizuma, Toshiki Endo, Makoto Ohta, Yasushi Matsumoto, Miki Fujimura, Teiji Tominaga
BACKGROUND: Transcranial Doppler (TCD) is used to monitor cerebral vasospasm after subarachnoid hemorrhage (SAH), but its diagnostic ability is reported to be limited. Therefore, the purpose of this study was to investigate the relationship between the diagnosability of TCD and the localization of the vasospasm. METHODS: This retrospective study included 20 patients who presented with symptomatic vasospasm after SAH. All 20 patients underwent daily TCD examinations and cerebral angiography after the onset of delayed cerebral ischemia...
2016: Cerebrovascular Diseases Extra
Jae-Sang Oh, Kyeong-Seok Lee, Jai-Joon Shim, Seok-Mann Yoon, Jae-Won Doh, Hack-Gun Bae
OBJECTIVE: Decompressive craniectomy is an effective therapy to relieve high intracranial pressure after acute brain damage. However, the optimal timing for cranioplasty after decompression is still controversial. Many authors reported that early cranioplasty may contribute to improve the cerebral blood flow and brain metabolism. However, despite all the advantages, there always remains a concern that early cranioplasty may increase the chance of infection. The purpose of this retrospective study is to investigate whether the early cranioplasty increase the infection rate...
September 2016: Journal of Korean Neurosurgical Society
Joan Martí-Fàbregas, Sebastián Figueroa, Eva Martínez-Lizana, Irati Zubizarreta, David Carrera, Alejandro Martínez-Domeño, Luis Prats-Sánchez, Pol Camps-Renom, Elena Jiménez-Xarrié, Raquel Delgado-Mederos
Chronic hypoperfusion may hinder the washout of emboli coming from the heart and facilitate the formation of intra-cavitary thrombi. We investigated whether a decreased total cerebral blood flow (tCBF) resulted in recurrence of stroke and other vascular events in consecutive patients with cardioembolic stroke. We excluded patients with extra-cranial carotid or vertebral stenosis. The recorded tCBF was the sum of blood flow in both the carotid and vertebral extra-cranial arteries as measured with ultrasonography...
September 17, 2016: Ultrasound in Medicine & Biology
Daniel Schuepbach, Stephan T Egger, Heinz Boeker, Stefan Duschek, Stefan Vetter, Erich Seifritz, Sabine C Herpertz
Patients with schizophrenia show deficits in cognitive functioning, and studies on cerebral hemodynamics have revealed aberrant patterns of mean cerebral blood flow velocity (MFV), an equivalent of cerebral blood flow (CBF). Therefore, we carried out a controlled study that assessed MFV in schizophrenia during a well-known neuropsychological task, the Trail Making Test (TMT). We measured MFV in the middle cerebral arteries using functional transcranial Doppler sonography in 15 schizophrenia patients and 15 healthy subjects...
September 17, 2016: Brain and Cognition
Wahbi K El-Bouri, Stephen J Payne
OBJECTIVE: Models of the cerebral microvasculature are required at many different scales in order to understand the effects of microvascular topology on CBF. There are, however, no data-driven models at the arteriolar/venular scale. In this paper, we develop a data-driven algorithm based on available data to generate statistically accurate penetrating arterioles and venules. METHODS: A novel order-based density-filling algorithm is developed, based on statistical data including bifurcating angles, LDRs, and area-ratios...
September 19, 2016: Microcirculation: the Official Journal of the Microcirculatory Society, Inc
Delgerdalai Khashbat Md, Takashi Abe Md, Mungunbagana Ganbold Md, Seiji Iwamoto Md, Naoto Uyama Md, Saho Irahara Md, Youichi Otomi Md PhD, Masafumi Harada Md PhD, Teruyoshi Kageji Md PhD, Shinji Nagahiro Md PhD
PURPOSE: Arterial spin labeling (ASL) is an alternative method to Dynamic susceptibility contrast (DSC) perfusion MRI for brain tumors. However, ASL cerebral blood flow (CBF) can be easily affected by transit time. DSC MRI derived time to maximum of the residue function (Tmax) is possible to assess the transit time on ASL. METHODS: Thirty patients with brain tumors were studied using ASL and DSC MRI. The relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), Tmax, and mean transit time (MTT) were obtained from DSC MRI...
2016: Journal of Medical Investigation: JMI
Xavier Waltz, Andrew E Beaudin, Patrick J Hanly, Georgios D Mitsis, Marc J Poulin
Cerebral autoregulation (CA) impairment may contribute to the increased risk of stroke associated with obstructive sleep apnea (OSA). It is unknown if impaired CA is further exacerbated by isocapnic-hypoxia and whether it is improved by treatment of OSA with continuous positive airway pressure (CPAP). CA was assessed during wakefulness in 53 OSA patients (50.3 ± 9.3 years) and 21 controls (49.8 ± 8.6 years) at baseline and following a minimum of 1 month of effective CPAP therapy (OSA patients, n = 40)...
September 20, 2016: Journal of Physiology
Yasuhiko Kaku, Hiroaki Takei, Masafumi Miyai, Kentarou Yamashita, Jouji Kokuzawa
BACKGROUND AND AIMS: Cerebral revascularization strategies may become necessary in select patients who present with challenging cerebral aneurysms. In this study, we present the techniques of a moderate-flow extra-intracranial bypass using a short interposition vein graft and concurrent aneurysm management. METHODS: The short interposition vein graft was used for the reconstruction of complex cerebral aneurysms in nine patients. In eight of them, the superficial temporal artery (STA) main trunk was used as a donor site for the anastomosis of a short interposition vein graft, and an extracranial vertebral artery (VA) was used in one case...
2016: Acta Neurochirurgica. Supplement
Joel Aanerud, Per Borghammer, Anders Rodell, Kristjana Y Jónsdottir, Albert Gjedde
Brain energy metabolism is held to reflect energy demanding processes in neuropil related to the density and activity of synapses. There is recent evidence that men have higher density of synapses in temporal cortex than women. One consequence of these differences would be different rates of cortical energy turnover and blood flow in men and women. To test the hypotheses that rates of oxygen consumption (CMRO2) and cerebral blood flow are higher in men than in women in regions of cerebral cortex, and that the differences persist with aging, we used positron emission tomography to determine cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes...
September 14, 2016: Journal of Cerebral Blood Flow and Metabolism
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