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Jinge Yang, Dan Wu, Yong Tang, Huabei Jiang
Acupuncture has been an effective treatment for various pain in China for several thousand years. However, the mechanisms underlying this mysterious ancient healing are still largely unknown. Here we applied photoacoustic microscopy (PAM) to investigate brain hemodynamic changes in response to electronic acupuncture (EA) at ST36 (Zusanli). Due to the high optical absorption of blood at 532 nm, PAM could sensitively probe changes in hemoglobin concentration (HbT, i.e., cerebral blood volume [CBV]) of cortical regions in high resolution...
October 18, 2016: Journal of Biophotonics
Benedikt Wiestler, Anne Kluge, Mathias Lukas, Jens Gempt, Florian Ringel, Jürgen Schlegel, Bernhard Meyer, Claus Zimmer, Stefan Förster, Thomas Pyka, Christine Preibisch
Non-invasive, imaging-based examination of glioma biology has received increasing attention in the past couple of years. To this end, the development and refinement of novel MRI techniques, reflecting underlying oncogenic processes such as hypoxia or angiogenesis, has greatly benefitted this research area. We have recently established a novel BOLD (blood oxygenation level dependent) based MRI method for the measurement of relative oxygen extraction fraction (rOEF) in glioma patients. In a set of 37 patients with newly diagnosed glioma, we assessed the performance of a machine learning model based on multiple MRI modalities including rOEF and perfusion imaging to predict WHO grade...
October 14, 2016: Scientific Reports
Henrik B W Larsson, Mark B Vestergaard, Ulrich Lindberg, Helle K Iversen, Stig P Cramer
PURPOSE: Capillary transit time heterogeneity, measured as CTH, may set the upper limit for extraction of substances in brain tissue, e.g., oxygen. The purpose of this study was to investigate the feasibility of dynamic contrast-enhanced T1 weighted MRI (DCE-MRI) at 3 Tesla (T), in estimating CTH based on a gamma-variate model of the capillary transit time distribution. In addition, we wanted to investigate if a subtle increase of the blood-brain barrier permeability can be incorporated into the model, still allowing estimation of CTH...
October 12, 2016: Journal of Magnetic Resonance Imaging: JMRI
Paula L Croal, Ian D Driver, Susan T Francis, Penny A Gowland
The relationship between venous blood oxygenation and change in transverse relaxation rate (ΔR2(⁎)) plays a key role in calibrated BOLD fMRI. This relationship, defined by the parameter β, has previously been determined using theoretical simulations and experimental measures. However, these earlier studies have been confounded by the change in venous cerebral blood volume (CBV) in response to functional tasks. This study used a double-echo gradient echo EPI scheme in conjunction with a graded isocapnic hyperoxic sequence to assess quantitatively the relationship between the fractional venous blood oxygenation (1-Yv) and transverse relaxation rate of grey matter (ΔR2(⁎)GM), without inducing a change in vCBV...
October 5, 2016: NeuroImage
Marcel T H Oei, Frederick J A Meijer, Willem-Jan van der Woude, Ewoud J Smit, Bram van Ginneken, Mathias Prokop, Rashindra Manniesing
OBJECTIVES: We present a novel One-Step-Stroke protocol for wide-detector CT scanners that interleaves cerebral CTP with volumetric neck CTA (vCTA). We evaluate whether the resulting time gap in CTP affects the accuracy of CTP values. METHODS: Cerebral CTP maps were retrospectively obtained from 20 patients with suspicion of acute ischemic stroke and served as the reference standard. To simulate a 4 s gap for interleaving CTP with vCTA, we eliminated one acquisition at various time points of CTP starting from the bolus-arrival-time(BAT)...
October 7, 2016: European Radiology
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]
D R Wahl, M M Kim, M P Aryal, T S Lawrence, M Schipper, H A Parmar, Y Cao
No abstract text is available yet for this article.
October 1, 2016: International Journal of Radiation Oncology, Biology, Physics
Christine Bollwein, Annika Plate, Wieland H Sommer, Kolja M Thierfelder, Hendrik Janssen, Maximilian F Reiser, Andreas Straube, Louisa von Baumgarten
INTRODUCTION: Although the diagnostic performance of whole-brain computed tomographic perfusion (WB-CTP) in the detection of supratentorial infarctions is well established, its value in the detection of infratentorial strokes remains less well defined. We examined its diagnostic accuracy in the detection of infratentorial infarctions and compared it to nonenhanced computed tomography (NECT), aiming to identify factors influencing its detection rate. METHODS: Out of a cohort of 1380 patients who underwent WB-CTP due to suspected stroke, we retrospectively included all patients with MRI-confirmed infratentorial strokes and compared it to control patients without infratentorial strokes...
September 20, 2016: Neuroradiology
Kohsuke Kudo, Ikuko Uwano, Toshinori Hirai, Ryuji Murakami, Hideo Nakamura, Noriyuki Fujima, Fumio Yamashita, Jonathan Goodwin, Satomi Higuchi, Makoto Sasaki
PURPOSE: The purpose of the present study was to compare different software algorithms for processing DSC perfusion images of cerebral tumors with respect to i) the relative CBV (rCBV) calculated, ii) the cutoff value for discriminating low- and high-grade gliomas, and iii) the diagnostic performance for differentiating these tumors. METHODS: Following approval of institutional review board, informed consent was obtained from all patients. Thirty-five patients with primary glioma (grade II, 9; grade III, 8; and grade IV, 18 patients) were included...
September 20, 2016: Magnetic Resonance in Medical Sciences: MRMS
Pratik Talati, Swati Rane, Manus J Donahue, Stephan Heckers
Recent studies of patients in the early stage of psychosis have revealed increased cerebral blood volume (CBV) in specific subfields of the anterior hippocampus. These studies required injection of a contrast agent to measure steady state CBV. Here we used a novel, non-invasive method, inflow-based-vascular-space-occupancy with dynamic subtraction (iVASO-DS), to measure the arterial component of CBV (aCBV) in a single slice of the hippocampus. Based on evidence from contrast-enhanced CBV studies, we hypothesized increased aCBV in the anterior hippocampus in early psychosis...
October 30, 2016: Psychiatry Research
Carlos Iribarren, Abdelkader Rahmaoui, Aidan A Long, Stanley J Szefler, Mary S Bradley, Gillis Carrigan, Mark D Eisner, Hubert Chen, Theodore A Omachi, Michael E Farkouh, Kenneth J Rothman
BACKGROUND: EXCELS was a postmarketing commitment to the US Food and Drug Administration to assess long-term safety of omalizumab in an observational setting, focusing predominantly on malignancies. OBJECTIVE: To examine a potential association between omalizumab and cardiovascular (CV)/cerebrovascular (CBV) events in EXCELS. METHODS: Cohort study of patients (≥12 years of age) with moderate-to-severe allergic asthma followed ≤5 years, treated with omalizumab (n = 5007) or not treated with omalizumab (n = 2829) at baseline...
September 14, 2016: Journal of Allergy and Clinical Immunology
Jyoji Nakagawara
Hemodynamic cerebral ischemia has been conceptually confirmed by positron emission tomography (PET) imaging, and misery perfusion could be compensated with both vascular and metabolic reserve; however, these compensatory reserve capacities do not always respond in the same manner from short-term to long-term compromise of hemodynamic cerebral ischemia.In patients with acute misery perfusion, CMRO2 is immediately compensated by a marked increase of OEF combined with a limited increase of CBV. In patients with chronic misery perfusion, a moderate increase of OEF is compatible with a moderate increase of CBV, which could correlate with a moderate decrease of vascular reserve (VR)...
2016: Acta Neurochirurgica. Supplement
Michael M Tymko, Caroline A Rickards, Rachel J Skow, Nathan C Ingram-Cotton, Michael K Howatt, Trevor A Day
Steady-state tilt has no effect on cerebrovascular reactivity to increases in the partial pressure of end-tidal carbon dioxide (PETCO2). However, the anterior and posterior cerebral circulations may respond differently to a variety of stimuli that alter central blood volume, including lower body negative pressure (LBNP). Little is known about the superimposed effects of head-up tilt (HUT; decreased central blood volume and intracranial pressure) and head-down tilt (HDT; increased central blood volume and intracranial pressure), and LBNP on cerebral blood flow (CBF) responses...
September 2016: Physiological Reports
Manus J Donahue, Meher R Juttukonda, Jennifer M Watchmaker
Functional neuroimaging with blood oxygenation level-dependent (BOLD) contrast has emerged as the most popular method for evaluating qualitative changes in brain function in humans. At typical human field strengths (1.5-3.0 T), BOLD contrast provides a measure of changes in transverse water relaxation rates in and around capillary and venous blood, and as such provides only a surrogate marker of brain function that depends on dynamic changes in hemodynamics (e.g., cerebral blood flow and volume) and metabolism (e...
September 10, 2016: NeuroImage
Sarah Perreault, Julie Baker, Erin Medoff, Kathryn Pratt, Francine Foss, Iris Isufi, Stuart Seropian, Dennis L Cooper
PURPOSE: Carmustine (BCNU) is used in the conditioning regimens BEAM and CBV for autologous stem cell transplantation. Carmustine-related infusion reactions, while not described in the BEAM literature, occurred in 95 % of patients who received CBV. The most common symptoms include flushing, facial pain, headache, and hypotension. These reactions have been attributed to the absolute ethanol that is used in the reconstitution process or alternatively by a direct effect of carmustine. It is currently recommended that carmustine 300 mg/m(2) be infused over at least 100 min (3-5 mg/m(2)/min)...
September 10, 2016: Supportive Care in Cancer: Official Journal of the Multinational Association of Supportive Care in Cancer
Dieter Henrik Heiland, Theo Demerath, Elias Kellner, Valerij G Kiselev, Dietmar Pfeifer, Oliver Schnell, Ori Staszewski, Horst Urbach, Astrid Weyerbrock, Irina Mader
The purpose of this study was to investigate the molecular background of cerebral blood volume (CBV) and vessel size (VS) of capillaries in glioblastoma multiforme (GBM). Both parameters are derived from extended perfusion MR imaging.A prospective case study including 21 patients (median age 66 years, 10 females) was performed. Before operation, CBV and VS of contrast enhancing tumor were assessed. Tissue was sampled from the assessed areas under neuronavigation control. After RNA extraction, transcriptional data was analyzed by Weighted Gene Co-Expression Network Analysis (WGCNA) and split into modules based on its network affiliations...
August 23, 2016: Oncotarget
Akihito Kato, Hiroyuki Morishima, Goro Nagashima
<i>Background</i>:Sinking skin flap syndrome(SSFS)manifests as subjective symptoms, such as headache, dizziness, and undue fatigability, in addition to neurologic symptoms, such as hemiplegia, aphasia, and perceived failure, when the skin over a bone defect sinks in the weeks or months following a decompressive craniectomy. Indeed, these symptoms can improve after a cranioplasty. <i>Case presentation</i>:A 58-year-old woman presented with a disturbance of consciousness. She was found to have a subarachnoid hemorrhage due to a ruptured right middle cerebral artery aneurysm...
September 2016: No Shinkei Geka. Neurological Surgery
Harshan Ravi, Peiying Liu, Shin-Lei Peng, Hanli Liu, Hanzhang Lu
Hemodynamic mapping using gas inhalation has received increasing interest in recent years. Cerebrovascular reactivity (CVR), which reflects the ability of the brain vasculature to dilate in response to a vasoactive stimulus, can be measured by CO2 inhalation with continuous acquisition of blood oxygen level-dependent (BOLD) magnetic resonance images. Cerebral blood volume (CBV) can be measured by O2 inhalation. These hemodynamic mapping methods are appealing because of their absence of gadolinium contrast agent, their ability to assess both baseline perfusion and vascular reserve, and their utility in calibrating the functional magnetic resonance imaging (fMRI) signal...
November 2016: NMR in Biomedicine
T B Nguyen, G O Cron, K Bezzina, K Perdrizet, C H Torres, S Chakraborty, J Woulfe, G H Jansen, R E Thornhill, B Zanette, I G Cameron
BACKGROUND AND PURPOSE: Tumor CBV is a prognostic and predictive marker for patients with gliomas. Tumor CBV can be measured noninvasively with different MR imaging techniques; however, it is not clear which of these techniques most closely reflects histologically-measured tumor CBV. Our aim was to investigate the correlations between dynamic contrast-enhanced and DSC-MR imaging parameters and immunohistochemistry in patients with gliomas. MATERIALS AND METHODS: Forty-three patients with a new diagnosis of glioma underwent a preoperative MR imaging examination with dynamic contrast-enhanced and DSC sequences...
September 1, 2016: AJNR. American Journal of Neuroradiology
Ruihua Shi, Tao Jiang, Lifang Si, Min Li
PURPOSE: To investigate the correlations of magnetic resonance, perfusion-weighed imaging (PWI) parameters and microvessel density (MVD) in meningioma. METHODS: 48 patients with pathologically confirmed meningioma (grade I, 38 cases; grade II+III, 10 cases) completed preoperative routine magnetic resonance imaging (MRI) and PWI. The cerebral blood volume (CBV) map of solid tumor region and the mean of maximum relative cerebral blood volume (rCBV) were then calculated...
May 2016: Journal of B.U.ON.: Official Journal of the Balkan Union of Oncology
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