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Dual echo vessel-encoded ASL for simultaneous BOLD and CBF reactivity assessment in patients with ischemic cerebrovascular disease

Carlos C. Faraco, Megan K. Strother, Lindsey M. Dethrage, Lori Jordan, Robert Singer, Paul F. Clemmons, Manus J. Donahue
2014 Magnetic Resonance in Medicine  
Purpose-Blood oxygenation level-dependent (BOLD)-weighted and vessel-encoded arterial spin labeling (VE-ASL) MRI provide complementary information and can be used in sequence to gauge hemodynamic contributions  ...  However, BOLD signal changes did not differ significantly between labeling scenarios (P>0.003) or across territories (P>0.002), indicating BOLD signal changes in response to carbogen offer low sensitivity  ...  Recent evidence suggests that reduction of BOLD SNR as a result of background suppression application during dual echo ASL does not significantly decrease the sensitivity of the BOLD contrast as measured  ... 
doi:10.1002/mrm.25268 pmid:24757044 pmcid:PMC4435663 fatcat:yodya2yz3rafjpojcorireks3y

Measurement of cerebral perfusion with arterial spin labeling: Part 1. Methods

2007 Journal of the International Neuropsychological Society  
Arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) method that provides a highly repeatable quantitative measure of cerebral blood flow (CBF).  ...  ASL measures of perfusion can aid in the interpretation of the BOLD signal change and, when combined with BOLD, can measure the change in oxygen utilization accompanying changes in behavioral state.  ...  such as gadolinium, and arterial spin labeling MRI.  ... 
doi:10.1017/s1355617707070646 pmid:17445301 fatcat:jjd57u2lpfagll7befcvxvjdci

Dual-Echo Arterial Spin Labeling for Brain Perfusion Quantification and Functional Analysis

André Monteiro Paschoal, Fernando Fernandes Paiva, Renata Ferranti Leoni
2019 Concepts in magnetic resonance. Part A, Bridging education and research  
Arterial Spin Labeling (ASL) is a noninvasive MRI-based method to measure cerebral blood flow (CBF).  ...  We analyzed the influence of TE on CBF values and brain connectivity provided by CBF and concurrent BOLD (cc-BOLD) time series.  ...  Regarding acquisition and analysis, Ghariq and colleagues investigated some specific aspects of the signal and suggested the use of background suppression to reduce BOLD contamination and to increase CBF  ... 
doi:10.1155/2019/5040465 fatcat:nnr424rs5bcqhiml37mvo5mg7u

Resolving intrinsic ambiguities of the fMRI signal in the human brain [article]

Eulanca Y. Liu, Frank Haist, David D Shin, Richard B Buxton
2019 bioRxiv   pre-print
However, the BOLD signal is physiologically complex, depending on the baseline state of the brain and the balance of changes in blood flow and oxygen metabolism in response to a change in neural activity  ...  The MRI methods used required only an additional 12 minutes of scanning, can be implemented on any MRI system, and painted a more complete picture of the physiological effects of caffeine.  ...  Effects of background suppression on the sensitivity of dual-echo arterial spin labeling MRI for BOLD and CBF signal changes.  ... 
doi:10.1101/833681 fatcat:bwwivzkyojfivktld2ox7vzp2e

Calibrated bold fMRI with an optimized ASL-BOLD dual-acquisition sequence

María A. Fernández-Seara, Zachary B. Rodgers, Erin K. Englund, Felix W. Wehrli
2016 NeuroImage  
The concatenation of these two imaging sequences allowed separate optimization of the acquisition for CBF and BOLD data.  ...  Further, the potential of the dualacquisition sequence for M-mapping on the basis of a hypercapnia gas breathing challenge and for quantification of CMRO 2 changes in response to a motor activation task  ...  Acknowledgments The authors are indebted to Dr. Benedikt Poser for providing the code of the dual-echo EPI sequence.  ... 
doi:10.1016/j.neuroimage.2016.08.007 pmid:27502047 pmcid:PMC5159288 fatcat:g2wafxhanzg5thzbzv74lmvyha

Applications of arterial spin labeled MRI in the brain

John A. Detre, Hengyi Rao, Danny J.J. Wang, Yu Fen Chen, Ze Wang
2012 Journal of Magnetic Resonance Imaging  
It has been almost two decades since the use of arterial spin labeling (ASL) for noninvasive perfusion imaging was first reported.  ...  As a result, basic science and clinical applications of ASL MRI have begun to proliferate. Although ASL MRI can be carried out in any organ, most studies to date have focused on the brain.  ...  greatly facilitate the use of background suppression pulses to reduce the static brain signal and increase sensitivity (35) (36) (37) .  ... 
doi:10.1002/jmri.23581 pmid:22246782 pmcid:PMC3326188 fatcat:jjjie2xdrjaupl3zcv4nxt2jlu

Noninvasive measurement of the cerebral blood flow response in human lateral geniculate nucleus with arterial spin labeling fMRI

Kun Lu, Joanna E. Perthen, Robert O. Duncan, Linda M. Zangwill, Thomas T. Liu
2008 Human Brain Mapping  
Arterial spin labeling (ASL) is an MRI method that can provide direct measures of functional cerebral blood flow (CBF) changes.  ...  However, due in part to the low intrinsic signal-to-noise ratio of the ASL method, measures of functional CBF changes in the LGN are challenging and have not previously been reported.  ...  Arterial spin labeling (ASL) is a noninvasive MRI method that can provide quantitative measures of CBF, which is a well-defined physiological quantity Williams et al., 1992] .  ... 
doi:10.1002/hbm.20459 pmid:17712783 pmcid:PMC2848166 fatcat:oxg3ezlcsbadljlr2l7m3iix2q

Measurement of cerebral perfusion using MRI

Egbert JW Bleeker, Matthias JP van Osch
2010 Imaging in Medicine  
In DSC-MRI, the conversion from signal changes to contrast agent concentration, the arterial input function measurement and the deconvolution method are the most important elements.  ...  MRI provides the opportunity of combining perfusion imaging with high-quality anatomical imaging and is therefore, for most brain diseases, the modality of choice.  ...  Acquisition is based on pseudo-continuous arterial spin labeling at 3 Tesla with 1650 ms label duration, 1525 ms delay, background suppression and a multislice single-shot echo-planar imaging readout module.future  ... 
doi:10.2217/iim.09.30 fatcat:du4trprf5zcsxbsqy365tyu2di

Comparison of 3 T and 7 T ASL techniques for concurrent functional perfusion and BOLD studies

Dimo Ivanov, Anna Gardumi, Roy A.M. Haast, Josef Pfeuffer, Benedikt A. Poser, Kâmil Uludağ
2017 NeuroImage  
A B S T R A C T Arterial spin labeling (ASL) is the primary non-invasive MRI approach to measure baseline cerebral blood flow (CBF) in healthy subjects and patients.  ...  To this aim, we investigated a wide range of parameters that can influence CBF and BOLD signal sensitivities: spatial resolution, labeling scheme, parallel imaging and echo time.  ...  Laurentius Huber for the implementation and validation of the tr-FOCI RF pulse and Sriranga Kashyap for help with the stimulus setup. The authors are indebted to Professor Dr.  ... 
doi:10.1016/j.neuroimage.2017.05.038 pmid:28528845 fatcat:ewfgglck4zgurfnm3vekmivuzu

Characterizing Resting-State Brain Function Using Arterial Spin Labeling

J. Jean Chen, Kay Jann, Danny J.J. Wang
2015 Brain Connectivity  
Arterial spin labeling (ASL) is an increasingly established magnetic resonance imaging (MRI) technique that is finding broader applications in studying the healthy and diseased brain.  ...  surrogate of the metabolic activity within corresponding networks; and (3) the study of resting-state dynamic CBF-BOLD coupling and cerebral metabolism: the use of dynamic CBF information obtained using  ...  Acknowledgments The authors acknowledge the following sources of funding: Canadian Institutes of Health Research (App. 286286, J.J.C.), Natural Sciences and Engineering Research Council of Canada (App.  ... 
doi:10.1089/brain.2015.0344 pmid:26106930 pmcid:PMC4652156 fatcat:bcp4otgrcnabfn3iqkf72mlriq

Noise Reduction in Arterial Spin Labeling Based Functional Connectivity Using Nuisance Variables

Kay Jann, Robert X. Smith, Edgar A. Rios Piedra, Mirella Dapretto, Danny J. J. Wang
2016 Frontiers in Neuroscience  
of healthy adults using state of the art 3D background-suppressed (BS) GRASE pseudo-continuous ASL (pCASL) and dual-echo 2D-EPI pCASL sequences.  ...  Furthermore, 3D BS GRASE pCASL shows much higher temporal SNR compared to dual-echo 2D-EPI pCASL and similar effects of noise reduction as those observed for BOLD.  ...  of healthy adults using state of the art 3D background-suppressed (BS) GRASE pseudo-continuous ASL (pCASL) and dual-echo 2D-EPI pCASL sequences.  ... 
doi:10.3389/fnins.2016.00371 pmid:27601973 pmcid:PMC4993769 fatcat:lkvd2zvd7rbjpivozmzujsuau4

Cerebral oxygen extraction fraction MRI: techniques and applications [article]

Dengrong Jiang, Hanzhang Lu
2022 arXiv   pre-print
These MRI OEF techniques are based on T2 of blood, phase of blood signal, susceptibility of blood-containing voxel, effect of deoxyhemoglobin on signal behavior in extravascular tissue, and calibration  ...  of BOLD signal using gas-inhalation.  ...  CBF can be measured globally by using phase-contrast MRI to quantify blood flow in the feeding arteries 29 or regionally by using arterial spin labeling (ASL) MRI. 30 It is worth noting that non-invasive  ... 
arXiv:2202.01350v1 fatcat:hefhe7f5hbabzjtm4pmudscdpy

Arterial Spin Labeling (ASL) fMRI: Advantages, Theoretical Constrains and Experimental Challenges in Neurosciences

Ajna Borogovac, Iris Asllani
2012 International Journal of Biomedical Imaging  
Arterial spin labeling (ASL) is a noninvasive fMRI technique that uses arterial water as an endogenous tracer to measure CBF.  ...  While underscoring the main advantages of ASL versus other techniques such as BOLD, we also expound on inherent challenges and confounds in ASL perfusion imaging.  ...  Acknowledgments The authors are greatly indebted to Scott Small, M.D., for insightful discussions regarding the application of fMRI in disease.  ... 
doi:10.1155/2012/818456 pmid:22966219 pmcid:PMC3432878 fatcat:mm5qzhspjnacfi6kt6ldtnzk7e

Laminar perfusion imaging with zoomed arterial spin labeling at 7 Tesla [article]

Xingfeng Shao, Fanhua Guo, Qinyang Shou, Kai Wang, Kay Jann, Lirong Yan, Arthur W. Toga, Peng Zhang, Danny JJ Wang
2021 bioRxiv   pre-print
Laminar fMRI based on BOLD and CBV contrast at ultrahigh magnetic fields has been applied for studying the dynamics of mesoscopic brain networks.  ...  Here we introduce a novel 3D zoomed pseudo-continuous arterial spin labeling technique at 7T that offers the unique capability for quantitative measurements of laminar cerebral blood flow (CBF) both at  ...  Acknowledgments This work was supported by the National Institute of Health (NIH) grant UH3-NS100614, S10-OD025312, R01-NS114382 and R01-EB028297.  ... 
doi:10.1101/2021.04.13.439689 fatcat:muhly3iiqjcjvdzk4xla36ivly

A Primer on Functional Magnetic Resonance Imaging

Gregory G. Brown, Joanna E. Perthen, Thomas T. Liu, Richard B. Buxton
2007 Neuropsychology Review  
The physiological complexity of the BOLD signal is emphasized. In the third section, arterial spin labeling (ASL) measures of cerebral blood flow are presented.  ...  Arterial spin labeling inverts or saturates the magnetization of flowing spins to measure the rate of delivery of blood to capillaries.  ...  With the use of background suppression methods and spin-echo readouts, ASL functional measures have been shown to be less prone than BOLD to false activations during overt speech paradigms, reflecting  ... 
doi:10.1007/s11065-007-9028-8 pmid:17468956 fatcat:v4c7dkp3xvantedcmh62kmq55m
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