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Cerebrovascular Reactivity in the Brain White Matter: Magnitude, Temporal Characteristics, and Age Effects

Binu P Thomas, Peiying Liu, Denise C Park, Matthias JP van Osch, Hanzhang Lu
2013 Journal of Cerebral Blood Flow and Metabolism  
With age, WM CVR response becomes greater and faster, which is opposite to the changes seen in the GM.  ...  The cerebrovascular reactivity (CVR) index showed that the value of CVR in the WM (0.03±0.002%/mm Hg) was positive, but was significantly lower than that in the gray matter (GM) (0.22 ± 0.01%/mm Hg).  ...  A proposed mechanism to explain the delay in cerebrovascular reactivity (CVR) response in the white matter (WM).  ... 
doi:10.1038/jcbfm.2013.194 pmid:24192640 pmcid:PMC3915204 fatcat:o6ynjx4evbcixlfy53ja2a57fa

Cerebrovascular-Reactivity Mapping Using MRI: Considerations for Alzheimer's Disease

J. J. Chen
2018 Frontiers in Aging Neuroscience  
However, there is growing recognition of the link between cerebrovascular dysfunction and AD, supported by continuous experimental evidence in the animal and human literature.  ...  This review focuses on the use of MRI to map CVR, paying specific attention to recent developments in MRI methodology and on the emerging stimulus-free approaches to CVR mapping.  ...  Additionally, the same group proposed the use of progressive hypercapnia (CO 2 ramps) , in which both hypercapnia and hypocapnia are progressively induced through a ramp stimulus.  ... 
doi:10.3389/fnagi.2018.00170 pmid:29922153 pmcid:PMC5996106 fatcat:yogcumzzg5fvvkrcrwfvjip5mq

Regional Cerebrovascular Reactivity and Cognitive Performance in Healthy Aging

Sarah J Catchlove, Todd B Parrish, Yufen Chen, Helen Macpherson, Matthew E Hughes, Andrew Pipingas
2018 Journal of Experimental Neuroscience  
Cerebrovascular reactivity (CVR) reflects the response of brain blood vessels to vasoactive stimuli, such as neural activity.  ...  When analyzing age groups separately, CVR in the hippocampus contributed significantly to memory score in the older group and was also related to subjective memory complaints.  ...  Acknowledgements Research was supported by a grant from the Barbara Dicker Brain Sciences Association. ME Hughes is supported by the Australian National Imaging Facility.  ... 
doi:10.1177/1179069518785151 pmid:30013388 pmcid:PMC6043917 fatcat:tet4o5bsgjdj3gijnxri4s2l4i

Neural and vascular variability and the fMRI-BOLD response in normal aging

Sridhar S. Kannurpatti, Michael A. Motes, Bart Rypma, Bharat B. Biswal
2010 Magnetic Resonance Imaging  
Neural, vascular and structural variables contributing to the BOLD signal response variability were investigated in younger and older humans.  ...  Mean activation volume was reduced by 45, 40 and 38% in the elderly group during the motor, cognitive and breath hold tasks respectively compared to the younger.  ...  Acknowledgments This study was supported by NIH grants NS049176-01A2 (BB) and AG029523-02 (BR).  ... 
doi:10.1016/j.mri.2009.12.007 pmid:20117893 pmcid:PMC2860003 fatcat:x5bnmhkrljfo5mhsydv4nlhghi

Integration of cerebrovascular CO2 reactivity and chemoreflex control of breathing: mechanisms of regulation, measurement, and interpretation

Philip N. Ainslie, James Duffin
2009 American Journal of Physiology. Regulatory Integrative and Comparative Physiology  
We discuss in detail the assessment and interpretation of cerebrovascular reactivity to CO 2.  ...  Cerebrovascular reactivity and ventilatory response to PaCO 2 are therefore tightly linked, so that the regulation of CBF has an important role in stabilizing breathing during fluctuating levels of chemical  ...  ACKNOWLEDGMENTS The authors thank Karen Peebles, Kate Thomas, and Dr. Sam Lucas for skilled input and feedback.  ... 
doi:10.1152/ajpregu.91008.2008 pmid:19211719 fatcat:bkyx5hboxzgijj5clzz35exymq

The Utility of Cerebrovascular Reactivity MRI in Brain Rehabilitation: A Mechanistic Perspective

Venkatagiri Krishnamurthy, Justin D. Sprick, Lisa C. Krishnamurthy, Jolie D. Barter, Aaminah Turabi, Ihab M. Hajjar, Joe R. Nocera
2021 Frontiers in Physiology  
Improved vascular reactivity and cerebral blood flow are important factors in brain rehabilitation to facilitate desired cognitive and functional outcomes.  ...  Cerebrovascular reactivity (CVR), an index of cerebrovascular reserve, plays an important role in chemo-regulation of cerebral blood flow.  ...  MECHANISTIC OUTLOOK Cerebrovascular Response to a Bolus of CO 2 Cerebrovascular reactivity refers to the ability of cerebral vessels to constrict, and (more commonly) to dilate in response to changes in  ... 
doi:10.3389/fphys.2021.642850 pmid:33815146 pmcid:PMC8009989 fatcat:67orksjcwbf67b66rfpkne3xja

Investigation of the BOLD-Based MRI Signal Time Course During Short Breath-Hold Periods for Estimation of the Cerebrovascular Reactivity

Leonie Zerweck, Till-Karsten Hauser, Constantin Roder, Uwe Klose
2020 SN Comprehensive Clinical Medicine  
We aimed to investigate the required minimum breath-hold duration to detect distinct BOLD signals in the tissue of healthy subjects to find out how long the minimum breath-hold duration in clinical diagnostics  ...  For the prognosis of stroke, patients with moyamoya disease (MMD) require the estimation of remaining cerebrovascular reactivity.  ...  Introduction Moyamoya disease (MMD) is a cerebrovascular disease that leads to progressive stenosis of terminal parts of the internal carotid arteries (ICA) and the circulus of Willis.  ... 
doi:10.1007/s42399-020-00442-6 fatcat:3bakeqfimrfnzhrmh3bbmsctom

Effects of sevoflurane versus propofol on cerebrovascular reactivity to carbon dioxide during laparoscopic surgery

Wang C, Ni C, Li G, Li Y, Tao L, Li N, Wang J, Guo X
2017 Therapeutics and Clinical Risk Management  
this work Purpose: Cerebrovascular reactivity to carbon dioxide (CVR-CO2) reflects cerebrovascular reserve capacity, which is important in many brain disorders, including cerebrovascular and Alzheimer's  ...  The patients in group S were induced with propofol and maintained with sevoflurane. The patients in group P were induced and maintained with propofol (target-controlled infusion).  ...  Impaired cerebrovascular reactivity predicts recurrent symptoms in patients with carotid artery occlusion: a hypercapnia BOLD fMRI study. Intharakham K, Suwanprasert K, Muengtaweepongsa S.  ... 
doaj:55f810c033fa45fc845b7c3ef84f8be3 fatcat:q4vckrrnrrfqrbtn2tvfupc4uq

Cerebrovascular reactivity (CVR) MRI with CO2 challenge: A technical review

Peiying Liu, Jill B. De Vis, Hanzhang Lu
2018 NeuroImage  
Cerebrovascular reactivity (CVR) is an indicator of cerebrovascular reserve and provides important information about vascular health in a range of brain conditions and diseases.  ...  Unlike steady-state vascular parameters, such as cerebral blood flow (CBF) and cerebral blood volume (CBV), CVR measures the ability of cerebral vessels to dilate or constrict in response to challenges  ...  (to P.L.), and NIH P41 EB015909 (to H.L.).  ... 
doi:10.1016/j.neuroimage.2018.03.047 pmid:29574034 pmcid:PMC6150860 fatcat:gphfmpj3tvhaxozcam6bwahzhi

Loss of Coherence of Low Frequency Fluctuations of BOLD FMRI in Visual Cortex of Healthy Aged Subjects

Lirong Yan, Yan Zhuo, Bo Wang, Danny J.J Wang
2011 The Open Neuroimaging Journal  
These 3 resting state measurements were compared with task induced BOLD activation in the visual cortex of 2 groups of 10 young and 10 elderly subjects.  ...  Our results showed reduced functional connectivity and regional homogeneity of low frequency fluctuations of BOLD fMRI in aged subjects as compared to young subjects.  ...  It may be related to greater variances of vascular reactivity in aged compared to young subjects, which can be assessed using fMRI responses to hypercapnia challenge.  ... 
doi:10.2174/1874440001105010105 pmid:22216081 pmcid:PMC3245404 fatcat:ztaoxasuara3lhyx2idn66rqmy

A generalized procedure for calibrated MRI incorporating hyperoxia and hypercapnia

Claudine J. Gauthier, Richard D. Hoge
2012 Human Brain Mapping  
Calibrated MRI techniques use the changes in cerebral blood flow (CBF) and blood oxygenation level-dependent (BOLD) signal evoked by a respiratory manipulation to extrapolate the total BOLD signal attributable  ...  This parameter can then be used to estimate changes in the cerebral metabolic rate of oxygen consumption (CMRO 2 ) based on task-induced BOLD and CBF signals.  ...  ACKNOWLEDGMENTS The authors thank Carollyn Hurst, André Cyr, Tarik Hafyane, and É lodie Boudes for help with data acquisition, Cécile Madjar for help with data acquisition, data analysis, and helpful discussions  ... 
doi:10.1002/hbm.21495 pmid:23015481 fatcat:7624rceduvd3xf5jicgkn3a6fe

Cerebral Blood Flow Measurements in Adults: A Review on the Effects of Dietary Factors and Exercise

Peter Joris, Ronald Mensink, Tanja Adam, Thomas Liu
2018 Nutrients  
This review summarizes the impact of specific dietary determinants and physical exercise on CBF in adults and discusses the relation between these effects with potential changes in cognitive function.  ...  Finally, long-term exercise training may be a promising approach to improve CBF, as increases in perfusion may contribute to the beneficial effects on cognitive functioning observed following increased  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/nu10050530 pmid:29693564 pmcid:PMC5986410 fatcat:6mo5zqxs2ngkhmf3izktvy7rae

Cerebrovascular Reactivity Mapping Without Gas Challenges: A Methodological Guide

Joana Pinto, Molly G. Bright, Daniel P. Bulte, Patrícia Figueiredo
2021 Frontiers in Physiology  
Cerebrovascular reactivity (CVR) is defined as the ability of vessels to alter their caliber in response to vasoactive factors, by means of dilating or constricting, in order to increase or decrease regional  ...  Furthermore, the spatiotemporal dynamics of CVR observed in healthy subjects, reflecting regional differences in cerebral vascular tone and response, may also be important in functional MRI studies based  ...  INTRODUCTION Cerebrovascular reactivity (CVR) is an intrinsic regulatory mechanism whereby cerebral blood vessels adjust their caliber in response to a vasoactive stimulus, increasing or decreasing the  ... 
doi:10.3389/fphys.2020.608475 pmid:33536935 pmcid:PMC7848198 fatcat:4cgdmdj7ijg4tnanrprnq7rb7q

Vascular risk factors, cerebrovascular reactivity, and the default-mode brain network

Thaddeus J. Haight, R. Nick Bryan, Guray Erus, Christos Davatzikos, David R. Jacobs, Mark D'Esposito, Cora E. Lewis, Lenore J. Launer
2015 NeuroImage  
Cerebrovascular reactivity (CVR) was quantified as percentage change in blood-oxygen level dependent (BOLD) signal in activated voxels, which was mapped to a common brain template and log-transformed.  ...  Breath-hold functional MRI (fMRI) was performed in 541 women and men (mean age 50.4 years) from the Coronary Artery Risk Development in Young Adults (CARDIA) Brain MRI sub-study.  ...  ACKNOWLEDGEMENTS The Coronary Artery Risk Development in Young Adults Study (CARDIA) is supported by contracts HHSN268201300025C, HHSN268201300026C, HHSN268201300027C, HHSN268201300028C, HHSN268201300029C  ... 
doi:10.1016/j.neuroimage.2015.04.039 pmid:25917517 pmcid:PMC4469180 fatcat:6hnzkiifgncwtbvt6k6guvnkrq

Functional magnetic resonance imaging as a dynamic candidate biomarker for Alzheimer's disease

David Prvulovic, Arun L.W. Bokde, Frank Faltraco, Harald Hampel
2011 Progress in Neurobiology  
Due to its widespread application in neuroscience, functional neuroimaging has raised the interest of clinical researchers in its possible use as a diagnostic biomarker.  ...  Alzheimer"s disease serves as an ideal model to test this hypothesis supported by the neural network model of the healthy and diseased brain.  ...  These changes remained significant, even after correcting for the differences in BOLD response in the hypercapnia task.  ... 
doi:10.1016/j.pneurobio.2011.05.008 pmid:21722703 fatcat:qanvaqdw35dspgcr47k4o6iuqi
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