keyword
MENU ▼
Read by QxMD icon Read
search

CBV

keyword
https://www.readbyqxmd.com/read/28901185/evaluation-of-parametric-response-mapping-to-assess-therapeutic-response-to-human-mesenchymal-stem-cells-after-experimental-stroke
#1
Rui He, Anaïck Moisan, Olivier Detante, Chantal Rémy, Alexandre Krainik, Emmanuel Luc Barbier, Benjamin Lemasson
Stroke is the leading cause of disability in adults. After the very narrow time frame during which treatment by thrombolysis and mechanical thrombectomy is possible, cell therapy has huge potential for enhancing stroke recovery. Accurate analysis of the response to new therapy using imaging biomarkers is needed to assess therapeutic efficacy. The aim of this study was to compare 2 analysis techniques: the parametric response map (PRM), a voxel-based technique, and the standard whole-lesion approach. These 2 analyses were performed on data collected at 4 time points in a transient middle cerebral artery occlusion (MCAo) model, which was treated with human mesenchymal stem cells (hMSCs)...
August 2017: Cell Transplantation
https://www.readbyqxmd.com/read/28900832/spatial-discrimination-of-glioblastoma-and-treatment-effect-with-histologically-validated-perfusion-and-diffusion-magnetic-resonance-imaging-metrics
#2
Melissa A Prah, Mona M Al-Gizawiy, Wade M Mueller, Elizabeth J Cochran, Raymond G Hoffmann, Jennifer M Connelly, Kathleen M Schmainda
The goal of this study is to spatially discriminate tumor from treatment effect (TE), within the contrast-enhancing lesion, for brain tumor patients at all stages of treatment. To this end, the diagnostic accuracy of MRI-derived diffusion and perfusion parameters to distinguish pure TE from pure glioblastoma (GBM) was determined utilizing spatially-correlated biopsy samples. From July 2010 through June 2015, brain tumor patients who underwent pre-operative DWI and DSC-MRI and stereotactic image-guided biopsy were considered for inclusion in this IRB-approved study...
September 12, 2017: Journal of Neuro-oncology
https://www.readbyqxmd.com/read/28887332/the-cerebro-cardiovascular-response-to-periodic-squat-stand-maneuvers-in-healthy-subjects-a-time-domain-analysis
#3
Sam C Barnes, Naomi Ball, Victoria Joanna Haunton, Thompson G Robinson, Ronney B Panerai
BACKGROUND: Squat-stand maneuvers (SSMs) have been used to improve the coherence of transfer function analysis (TFA) estimates during the assessment of dynamic cerebral autoregulation (dCA). There is a need to understand the influence of peripheral changes resulting from SSMs on cerebral blood flow, which might confound estimates of dCA. METHODS: 29 healthy subjects underwent recordings at rest (5 min standing) and 15 SSMs (0.05Hz). Heart rate (3-lead ECG), end-tidal CO2 (capnography), blood pressure (Finometer), cerebral blood velocity (CBV, transcranial Doppler, MCA) and the angle of the thigh (tilt sensor) were measured continuously...
September 8, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28879406/whole-tumor-histogram-analysis-of-the-cerebral-blood-volume-map-tumor-volume-defined-by-11c-methionine-positron-emission-tomography-image-improves-the-diagnostic-accuracy-of-cerebral-glioma-grading
#4
Rongli Wu, Yoshiyuki Watanabe, Atsuko Arisawa, Hiroto Takahashi, Hisashi Tanaka, Yasunori Fujimoto, Tadashi Watabe, Kayako Isohashi, Jun Hatazawa, Noriyuki Tomiyama
PURPOSE: This study aimed to compare the tumor volume definition using conventional magnetic resonance (MR) and 11C-methionine positron emission tomography (MET/PET) images in the differentiation of the pre-operative glioma grade by using whole-tumor histogram analysis of normalized cerebral blood volume (nCBV) maps. MATERIALS AND METHODS: Thirty-four patients with histopathologically proven primary brain low-grade gliomas (n = 15) and high-grade gliomas (n = 19) underwent pre-operative or pre-biopsy MET/PET, fluid-attenuated inversion recovery, dynamic susceptibility contrast perfusion-weighted magnetic resonance imaging, and contrast-enhanced T1-weighted at 3...
September 6, 2017: Japanese Journal of Radiology
https://www.readbyqxmd.com/read/28865944/false-ischaemic-penumbras-in-ct-perfusion-in-patients-with-carotid-artery-stenosis-and-changes-following-angioplasty-and-stenting
#5
A J Mosqueira, J M Pumar, S Arias, M Rodríguez-Yáñez, M Blanco Ulla, F Vázquez Herrero, J Castillo
INTRODUCTION: Carotid artery stenosis influences CT perfusion (CTP) studies, sometimes manifesting as a false ischaemic penumbra (FIP). This study aims to estimate the incidence of FIP in patients with carotid artery stenosis, establish their relationship with the degree of stenosis, and measure quantitative and qualitative changes in CTP after carotid angioplasty and stenting (CAS). METHODS: Between October 2013 and June 2015, we prospectively selected 26 patients with carotid stenosis who underwent CAS, with CTP being performed 2-10 days before and after CAS...
August 30, 2017: Neurología: Publicación Oficial de la Sociedad Española de Neurología
https://www.readbyqxmd.com/read/28861622/perfusion-magnetic-resonance-imaging-in-pediatric-brain-tumors
#6
F Dallery, R Bouzerar, D Michel, C Attencourt, V Promelle, J Peltier, J M Constans, O Balédent, C Gondry-Jouet
PURPOSE: The use of DSC-MR imaging in pediatric neuroradiology is gradually growing. However, the number of studies listed in the literature remains limited. We propose to assess the perfusion and permeability parameters in pediatric brain tumor grading. METHODS: Thirty children with a brain tumor having benefited from a DSC-MR perfusion sequence have been retrospectively explored. Relative CBF and CBV were computed on the ROI with the largest lesion coverage. Assessment of the lesion's permeability was also performed through the semi-quantitative PSR parameter and the K2 model-based parameter on the whole-lesion ROI and a reduced ROI drawn on the permeability maps...
August 31, 2017: Neuroradiology
https://www.readbyqxmd.com/read/28829628/evaluation-of-cerebral-hemodynamics-by-computed-tomography-perfusion-imaging-before-and-after-cranioplasty-in-patients-with-brain-injury
#7
Wang Gang, Yu Lan, Zhou Xiao Ming, Li Zhi Ming, Zhao Rui Rui, Niu Lei, Sui Qing Lan, Li Hui Jian
OBJECTIVE: To assess the clinical significance of computed tomography perfusion (CTP) imaging by evaluating cerebral hemodynamic changes quantitatively and qualitatively both before and after cranioplasty in patients with brain injury. METHODS: Sixteen patients with cerebral trauma underwent CTP imaging 2 days before and 10-15 days after cranioplasty. The cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time and time to peak were analysed in both the affected and corresponding contralateral regions, including the basal ganglia, thalamus, cortex and white matter...
August 22, 2017: Brain Injury: [BI]
https://www.readbyqxmd.com/read/28827669/cerebral-blood-volume-and-oxygen-supply-uniformly-increase-following-various-intrathoracic-pressure-strains
#8
Zhongxing Zhang, Nina Bolz, Marco Laures, Margit Oremek, Christoph Schmidt, Ming Qi, Ramin Khatami
Intrathoracic pressure (ITP) swings challenge many physiological systems. The responses of cerebral hemodynamics to different ITP swings are still less well-known due to the complexity of cerebral circulation and methodological limitation. Using frequency-domain near-infrared spectroscopy and echocardiography, we measured changes in cerebral, muscular and cardiac hemodynamics in five graded respiratory maneuvers (RM), breath holding, moderate and strong Valsalva maneuvers (mVM/sVM) with 20 and 40 cmH2O increments in ITP, moderate and strong Mueller maneuvers (mMM/sMM) with 20 and 40 cmH2O decrements in ITP controlled by esophageal manometry...
August 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28827098/diagnostic-accuracy-of-automatic-normalization-of-cbv-in-glioma-grading-using-t1-weighted-dce-mri
#9
Prativa Sahoo, Rakesh K Gupta, Pradeep K Gupta, Ashish Awasthi, Chandra M Pandey, Mudit Gupta, Rana Patir, Sandeep Vaishya, Sunita Ahlawat, Indrajit Saha
PURPOSE: Aim of this retrospective study was to compare diagnostic accuracy of proposed automatic normalization method to quantify the relative cerebral blood volume (rCBV) with existing contra-lateral region of interest (ROI) based CBV normalization method for glioma grading using T1-weighted dynamic contrast enhanced MRI (DCE-MRI). MATERIAL AND METHODS: Sixty patients with histologically confirmed gliomas were included in this study retrospectively. CBV maps were generated using T1-weighted DCE-MRI and are normalized by contralateral ROI based method (rCBV_contra), unaffected white matter (rCBV_WM) and unaffected gray matter (rCBV_GM), the latter two of these were generated automatically...
August 4, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/28810259/reliability-reproducibility-and-prognostic-accuracy-of-the-alberta-stroke-program-early-ct-score-on-ct-perfusion-and-non-contrast-ct-in-hyperacute-stroke
#10
Jillian Naylor, Leonid Churilov, Ziyuan Chen, Miriam Koome, Neil Rane, Bruce C V Campbell
BACKGROUND: Alberta Stroke Program Early CT Score (ASPECTS) assesses early ischemic change on non-contrast CT (NCCT). We hypothesised that assessing ASPECTS regions on CT Perfusion (CTP) rather than NCCT would improve inter-rater agreement and prognostic accuracy, particularly in patients presenting early after stroke onset. METHODS: Ischemic stroke patients treated with intravenous alteplase from 2009 to 2014 at our institution were included in this study. Inter-rater agreement and prognostic accuracy of ASPECTS across modalities were analysed by the time between stroke onset and initial NCCT, dichotomized 1st quartile versus quartiles 2-4, referred to as epochs...
August 16, 2017: Cerebrovascular Diseases
https://www.readbyqxmd.com/read/28776269/apparent-brain-temperature-imaging-with-multi-voxel-proton-magnetic-resonance-spectroscopy-compared-with-cerebral-blood-flow-and-metabolism-imaging-on-positron-emission-tomography-in-patients-with-unilateral-chronic-major-cerebral-artery-steno-occlusive-disease
#11
Takamasa Nanba, Hideaki Nishimoto, Yoshichika Yoshioka, Toshiyuki Murakami, Makoto Sasaki, Ikuko Uwano, Shunrou Fujiwara, Kazunori Terasaki, Kuniaki Ogasawara
PURPOSE: The purpose of the present study was to determine whether apparent brain temperature imaging using multi-voxel proton magnetic resonance (MR) spectroscopy correlates with cerebral blood flow (CBF) and metabolism imaging in the deep white matter of patients with unilateral chronic major cerebral artery steno-occlusive disease. METHODS: Apparent brain temperature and CBF and metabolism imaging were measured using proton MR spectroscopy and (15)O-positron emission tomography (PET), respectively, in 35 patients...
August 3, 2017: Neuroradiology
https://www.readbyqxmd.com/read/28762185/consideration-of-the-intracranial-pressure-threshold-value-for-the-initiation-of-traumatic-brain-injury-treatment-a-xenon-ct-and-perfusion-ct-study
#12
Mitsuru Honda, Ryo Ichibayashi, Ginga Suzuki, Hiroki Yokomuro, Yoshikatsu Seiki, Shigeru Sase, Taichi Kishi
BACKGROUND: Monitoring of intracranial pressure (ICP) is considered to be fundamental for the care of patients with severe traumatic brain injury (TBI) and is routinely used to direct medical and surgical therapy. Accordingly, some guidelines for the management of severe TBI recommend that treatment be initiated for ICP values >20 mmHg. However, it remained to be accounted whether there is a scientific basis to this instruction. The purpose of the present study was to clarify whether the basis of ICP values >20 mmHg is appropriate...
July 31, 2017: Neurocritical Care
https://www.readbyqxmd.com/read/28761534/efficacy-of-superficial-temporal-artery-middle-cerebral-artery-bypass-in-cerebrovascular-steno-occlusive-diseases-hemodynamics-assessed-by-perfusion-computed-tomography
#13
Woo-Keun Kwon, Taek-Hyun Kwon, Dong-Hyuk Park, Joo-Han Kim, Sung-Kon Ha
OBJECTIVES: Our purpose of this study was to assess the cerebral hemodynamic improvement with perfusion computed tomography (CT), before and after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in patients with cerebrovascular steno-occlusive diseases including both moyamoya disease and nonmoyamoya steno-occlusions. MATERIALS AND METHODS: Twenty-four STA-MCA bypasses were performed to 22 patients with symptomatic cerebrovascular steno-occlusive diseases, including both moyamoya disease and nonmoyamoya steno-occlusive diseases...
July 2017: Asian Journal of Neurosurgery
https://www.readbyqxmd.com/read/28760084/optimal-dilution-of-contrast-medium-for-quantitating-parenchymal-blood-volume-using-a-flat-panel-detector
#14
Takumi Kuriyama, Nobuyuki Sakai, Mikiya Beppu, Chiaki Sakai, Hirotoshi Imamura, Iwao Kojima, Katsuhiro Masago, Nobuyuki Katakami
Objective Similar to perfusion studies after acute ischemic stroke, measuring cerebral blood volume (CBV) via C-arm computed tomography before and after therapeutic interventions may help gauge subsequent revascularization. We tested serial dilutions of intra-arterial injectable contrast medium (CM) to determine the optimal CM concentration for quantifying parenchymal blood volume by flat-panel detector imaging (FD-PBV). Methods CM was diluted via saline power injector, instituting time delays for FD-PBV studies...
January 1, 2017: Journal of International Medical Research
https://www.readbyqxmd.com/read/28752130/design-analysis-of-an-mpi-human-functional-brain-scanner
#15
Erica E Mason, Clarissa Z Cooley, Stephen F Cauley, Mark A Griswold, Steven M Conolly, Lawrence L Wald
MPI's high sensitivity makes it a promising modality for imaging brain function. Functional contrast is proposed based on blood SPION concentration changes due to Cerebral Blood Volume (CBV) increases during activation, a mechanism utilized in fMRI studies. MPI offers the potential for a direct and more sensitive measure of SPION concentration, and thus CBV, than fMRI. As such, fMPI could surpass fMRI in sensitivity, enhancing the scientific and clinical value of functional imaging. As human-sized MPI systems have not been attempted, we assess the technical challenges of scaling MPI from rodent to human brain...
2017: Int J Magn Part Imaging
https://www.readbyqxmd.com/read/28746785/half-the-story-thermal-effects-on-within-host-infectious-disease-progression-in-a-warming-climate
#16
Alexander Stewart, Pascal I Hablützel, Martha Brown, Hayley V Watson, Sophie Parker-Norman, Anya V Tober, Anna G Thomason, Ida M Friberg, Joanne Cable, Joseph A Jackson
Immune defence is temperature-dependent in cold-blooded vertebrates (CBVs) and thus directly impacted by global warming. We asked whether immunity and within-host infectious disease progression are altered in CBVs under realistic climate warming in a seasonal mid-latitude setting. Going further, we also asked how large thermal effects are in relation to the effects of other environmental variation in such a setting (critical to our ability to project infectious disease dynamics from thermal relationships alone)...
July 26, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28740980/micro-engineered-perfusable-3d-vasculatures-for-cardiovascular-diseases
#17
Nishanth Venugopal Menon, Hui Min Tay, Soon Nan Wee, King Ho Holden Li, Han Wei Hou
Vessel geometries in microengineered in vitro vascular models are important to recapitulate a pathophysiological microenvironment for the study of flow-induced endothelial dysfunction and inflammation in cardiovascular diseases. Herein, we present a simple and novel extracellular matrix (ECM) hydrogel patterning method to create perfusable vascularized microchannels of different geometries based on the concept of capillary burst valve (CBV). No surface modification is necessary and the method is suitable for different ECM types including collagen, matrigel and fibrin...
July 25, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28736310/non-bold-contrast-for-laminar-fmri-in-humans-cbf-cbv-and-cmro2
#18
REVIEW
Laurentius Huber, Kâmil Uludağ, Harald E Möller
Functional magnetic resonance imaging (fMRI) using the blood oxygenation level-dependent (BOLD) contrast indirectly probes neuronal activity changes via evoked cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral metabolic rate of oxygen (CMRO2) changes. The gradient-echo BOLD signal is mostly sensitive to ascending veins in the tissue and to pial veins. Thereby, the achievable spatial specificity to neuronal activation is limited. Furthermore, the non-linear interaction of CBF, CBV and CMRO2 can hamper quantitative interpretations of the BOLD signal across cortical depths with different baseline physiology...
July 20, 2017: NeuroImage
https://www.readbyqxmd.com/read/28729160/echo-time-dependence-of-the-bold-response-transients-a-window-into-brain-functional-physiology
#19
Martin Havlicek, Dimo Ivanov, Benedikt A Poser, Kamil Uludag
The blood oxygenation level-dependent (BOLD) fMRI response to neuronal activation results from a complex interplay of induced metabolic and vascular changes. Thus, its transients, such as initial overshoot and post-stimulus undershoot, provide a window into the dynamic relationships of the underlying physiological variables. In this study, we propose multi-echo fMRI as a tool to investigate the physiological underpinnings of the BOLD signal, in particular, and brain functional physiology, in general. In the human visual cortex at 3 T, we observed that the BOLD response is nonlinearly dependent on echo-time (TE) and the amount of nonlinearity varies during the entire time-course...
July 18, 2017: NeuroImage
https://www.readbyqxmd.com/read/28729141/effects-of-transjugular-intrahepatic-portosystemic-shunt-tips-on-blood-volume-distribution-in-patients-with-cirrhosis
#20
Troels M Busk, Flemming Bendtsen, Jens H Henriksen, Stefan Fuglsang, Jens O Clemmesen, Fin S Larsen, Søren Møller
BACKGROUND: Cirrhosis is accompanied by portal hypertension with splanchnic and systemic arterial vasodilation, and central hypovolaemia. A transjugular intrahepatic portosystemic shunt (TIPS) alleviates portal hypertension, but also causes major haemodynamic changes. AIMS: To investigate effects of TIPS on regional blood volume distribution, and systemic haemodynamics. METHODS: Thirteen cirrhotic patients had their regional blood volume distribution determined with gamma-camera technique before and after TIPS...
June 27, 2017: Digestive and Liver Disease
keyword
keyword
44316
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"