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Interleaved quantitative BOLD: Combining extravascular R2ʹ - and intravascular R2-measurements for estimation of deoxygenated blood volume and hemoglobin oxygen saturation

Hyunyeol Lee, Erin K. Englund, Felix W. Wehrli
2018 NeuroImage  
Quantitative BOLD (qBOLD), a non-invasive MRI method for assessment of hemodynamic and metabolic properties of the brain in the baseline state, provides spatial maps of deoxygenated blood volume fraction  ...  (DBV) and hemoglobin oxygen saturation (HbO2) by means of an analytical model for the temporal evolution of free-induction-decay signals in the extravascular compartment.  ...  Acknowledgments This work was supported in part by NIH grants R01-HL122754, R01-HL109545, R21 EB022687, T32HL007954 and the National Center for Advancing Translational Sciences of the National Institutes  ... 
doi:10.1016/j.neuroimage.2018.03.043 pmid:29580967 pmcid:PMC5949279 fatcat:ys4mjqaztzbz3ju2j5hrydfcym

Blood oxygenation level-dependent (BOLD)-based techniques for the quantification of brain hemodynamic and metabolic properties - theoretical models and experimental approaches

Dmitriy A. Yablonskiy, Alexander L. Sukstanskii, Xiang He
2012 NMR in Biomedicine  
Combining measurement of OEF with measurement of CBF allows evaluation of oxygen consumption, CMRO 2 .  ...  Then, we describe a "through-space" effect -the influence of inhomogeneous magnetic fields, created in the extravascular space by intravascular deoxygenated blood, on the MR signal formation.  ...  Acknowledgments The authors are grateful to Professors Marcus Raichle, Felix Wehrli, Hanzhang Lu, Mark Conradi and Joseph Ackerman for helpful discussions.  ... 
doi:10.1002/nbm.2839 pmid:22927123 pmcid:PMC3510357 fatcat:iyglrvzeanhujowzigoig3tecm

Quantifying the Microvascular Origin of BOLD-fMRI from First Principles with Two-Photon Microscopy and an Oxygen-Sensitive Nanoprobe

L. Gagnon, S. Sakad i, F. Lesage, J. J. Musacchia, J. Lefebvre, Q. Fang, M. A. Yucel, K. C. Evans, E. T. Mandeville, J. Cohen-Adad, J. R. Polimeni, M. A. Yaseen (+6 others)
2015 Journal of Neuroscience  
However, the BOLD signal reflects changes in blood volume and oxygenation rather than neuronal activity per se.  ...  This framework is then used to quantify the contribution of individual vascular compartments and other factors to the BOLD signal for different magnet strengths and pulse sequences.  ...  The bottom-up model presented here will provide a validated framework to validate and potentially improve this MRF dictionary by accounting for the real geometry and oxygenation of cortical microvasculature  ... 
doi:10.1523/jneurosci.3555-14.2015 pmid:25716864 pmcid:PMC4339366 fatcat:js2kiyatrrezndxyodj25k67hq

The Cumulative Influence of Hyperoxia and Hypercapnia on Blood Oxygenation and R2*

Carlos C Faraco, Megan K Strother, Jeroen CW Siero, Daniel F Arteaga, Allison O Scott, Lori C Jordan, Manus J Donahue
2015 Journal of Cerebral Blood Flow and Metabolism  
Owing to complex interactions between hyperoxia and hypercapnia, quantitative effects of these gas mixtures on BOLD responses, blood and tissue R Ã 2 , and blood oxygenation are incompletely understood  ...  Results provide an outline for how blood oxygenation differs for several gas stimuli and provides quantitative information on how hypercapnic BOLD CVR and R Ã 2 are altered during hyperoxia.  ...  DISCLOSURE/CONFLICT OF INTEREST The authors declare no conflict of interest.  ... 
doi:10.1038/jcbfm.2015.168 pmid:26174329 pmcid:PMC4671125 fatcat:26rfy5n24bbezngo7ak3qj66ta

Physiologically informed dynamic causal modeling of fMRI data

Martin Havlicek, Alard Roebroeck, Karl Friston, Anna Gardumi, Dimo Ivanov, Kamil Uludag
2015 NeuroImage  
; (ii) feedforward neurovascular coupling that links neuronal activity to blood flow; and (iii) a balloon model that can account for vascular uncoupling between the blood flow and the blood volume.  ...  The functional MRI (fMRI) signal is an indirect measure of neuronal activity.  ...  Acknowledgments This work was financially supported by the Marie Curie Initial Training Network grant (PITN-GA-2009-238593) of EU and VIDI grant (452-11-002) of the Netherlands Organization for Scientific  ... 
doi:10.1016/j.neuroimage.2015.07.078 pmid:26254113 fatcat:aw3lforlmveoxbhmcl7ssjngwi

Foundations of advanced magnetic resonance imaging

Roland Bammer, Stefan Skare, Rexford Newbould, Chunlei Liu, Vincent Thijs, Stefan Ropele, David B. Clayton, Gunnar Krueger, Michael E. Moseley, Gary H. Glover
2005 Neurotherapeutics  
Some advanced MRI techniques have truly revolutionized the detection of disease states and MRI can nowwithin a few minutes-acquire important quantitative information noninvasively from an individual in  ...  any plane or volume at comparatively high resolution.  ...  of Stanford (NCRR P41 RR 09784), and the Lucas Foundation.  ... 
doi:10.1007/bf03206665 fatcat:a66utm5yn5dwxfvxx5s7hwg6ve

Foundations of advanced magnetic resonance imaging

Roland Bammer, Stefan Skare, Rexford Newbould, Chunlei Liu, Vincent Thijs, Stefan Ropele, David B. Clayton, Gunnar Krueger, Michael E. Moseley, Gary H. Glover
2005 NeuroRx  
Some advanced MRI techniques have truly revolutionized the detection of disease states and MRI can nowwithin a few minutes-acquire important quantitative information noninvasively from an individual in  ...  any plane or volume at comparatively high resolution.  ...  of Stanford (NCRR P41 RR 09784), and the Lucas Foundation.  ... 
doi:10.1602/neurorx.2.2.167 pmid:15897944 pmcid:PMC1064985 fatcat:vyfeyhkvtvfe3kg6iyxxgzzrgu

Towards a Quantitative and Objective Assessment of Renal Oxygenation Through Magnetic Resonance Imaging

Jon Thacker
2016 unpublished
There is a need for an objective, quantitative, and non-invasive measure of renal oxygenation.  ...  An invasive method for refining and calibrating the model is investigated that has the ability to independently measure blood and tissue PO 2 .  ...  In addition to R2', an ASE acquisition can be used to provide an estimate of the oxygen saturation of hemoglobin (SHb) and venous blood volume.  ... 
doi:10.21985/n2fd46 fatcat:2nvae7rog5h67eqf42c4fcmst4

MAGNETIC SUSCEPTIBILITY APPROACH FOR QUANTITATIVE CEREBRAL OXYGEN METABOLISM MAPPING

Jingwei Zhang
2017
map cerebral metabolic rate of oxygen (CMRO2) and oxygen extraction fraction (OEF) using QSM; 3) a new algorithm to improve SNR of QSM-based CMRO2 using prior knowledge; 4) a new algorithm called minimal  ...  local variance (MLV) to improve clinical practicality of QSM-based CMRO2 by removing the requirement of blood flow challenge.  ...  [Hb] = Hct • 0.34 g/ml M Hb = 2.48 µmol/ml Calculation of hemoglobin volume fraction in blood in blood Hb Ψ The hemoglobin volume fraction in blood Ψ Hb = 0.12 is estimated from [Hb], M Hb , and Hb  ... 
doi:10.7298/x4wd3xq6 fatcat:in3zw2ap2rba3fflgw72a6zgk4

New MRI Techniques for Nanoparticle Based Functional and Molecular Imaging

Lingzhi Hu
2012
Among these methods, R2* and susceptibility contrast generated by deoxygenated-hemoglobin (deoxy-Hb) can be used to estimate deoxy-Hb concentration and blood saturation (SO 2 ) because deoxy-Hb is highly  ...  Blood-Oxygenation-Level-Dependent (BOLD) MRI permits non-invasive detection of neural activation and metabolism by measuring T2* contrast generated by deoxygenated hemoglobin (11) .  ... 
doi:10.7936/k7kh0kfj fatcat:jtremsf4mfbrnn2iv3o5fklwba

Cardiovascular Activity [chapter]

Hans Gerhard Vogel
2007 Drug Discovery and Evaluation  
High-resolution animal positron emission tomography was recommended by Magata et al. (1995) for noninvasive measurement of cerebral blood flow with 15 O-water and glucose metabolic rate with 18 F-2fluoro  ...  MODIFICATIONS OF THE METHOD Ito et al. (1990) measured glucose utilization in the mouse brain by the simultaneous use of [ 14 C]2-deoxyglucose and [ 3 H]3-O-methylglucose.  ...  Pressure is measured directly in mmHg, while the conductivity of blood is used to estimate volume and allow construction of pressure-volume relationships in real time.  ... 
doi:10.1007/978-3-540-70995-4_2 fatcat:z75tsqr3nzhpric5ftzldlabra

Functional magnetic resonance imaging of schizophrenia

David Paul McAllindon
2008
loan, distribute and sell theses worldwide, for commercial or noncommercial purposes, in microform, paper, electronic and/or any other formats.  ...  Thanks Mom and Dad for all your support and encouragement through the years, including well past the age when you shouldn't have to worry about me.  ...  Although he didn't have funding himself, he was generous in finding another professor with funding and interest. My thanks go to Alan and to Dr. Philip Tibbo for giving me a chance.  ... 
doi:10.7939/r3-9ymy-s610 fatcat:6x2zz6ftzvaadpv7cbniq72xoi