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Experimental Design and the Relative Sensitivity of BOLD and Perfusion fMRI
2002
NeuroImage
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This information is then used to generate a model of relative sensitivity of the BOLD and perfusion methods for within-subject experimental designs of varying temporal frequency. ...
This paper compares the statistical power of BOLD and arterial spin labeling perfusion fMRI for a variety of experimental designs within and across subjects. ...
ACKNOWLEDGMENTS The authors thank Daniel Casasanto, Faez Siddiqi, and Irene Kan for their help with data acquisition. This work was supported in part by Grant HD39621. ...
doi:10.1006/nimg.2001.0990
pmid:11848692
fatcat:uf3dmglysbhupd6ektzboqzvnu
Arterial spin labeling perfusion fMRI with very low task frequency
2003
Magnetic Resonance in Medicine
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The present study investigates the relative sensitivities of ASL and BOLD contrast in detecting changes in motor cortex activation over a spectrum of frequencies of experimental design, where the alternating ...
The improved sensitivity of the ASL contrast for low task frequency and longitudinal studies, along with its superior power in group analysis, is expected to extend the range of experimental designs that ...
FIG. 1 . 1 Skeletal diagram depicting the experimental designs for perfusion fMRI. ...
doi:10.1002/mrm.10437
pmid:12704760
fatcat:gzsmjbdj6nc3plvilsbw55ixom
Perfusion fMRI for Functional Neuroimaging
[chapter]
2005
International review of neurobiology
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Second, the greater noise at low frequencies will cause a relative reduction in sensitivity for some experimental designs. ...
. now consider this important aspect of perfusion fMRI experimental design. ...
doi:10.1016/s0074-7742(05)66007-2
pmid:16387205
fatcat:oq6yidedpbfmjl2qlqpywf4ffm
To smooth or not to smooth? ROC analysis of perfusion fMRI data
2005
Magnetic Resonance Imaging
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In contrast to the BOLD fMRI, temporal smoothing or filtering reduces the power of perfusion fMRI data analyses whereas spatial smoothing is beneficial to the efficacy of analyses. D ...
Perfusion contrast manifests different noise properties compared with BOLD contrast, represented by the even distribution of noise power and spatial coherence across the frequency spectrum. ...
Acknowledgment This research was supported by NIH grants HD39621, P41-RR02395, DA015149, NS045839 and NSF grant BCS0224007. ...
doi:10.1016/j.mri.2004.11.009
pmid:15733791
fatcat:aod6hrvobvdkvbpdrhktk5yb5y
Empirical analyses of null-hypothesis perfusion FMRI data at 1.5 and 4 T
2003
NeuroImage
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Because of the typical pairwise subtraction approach in generating perfusion images, ASL contrast manifests different noise properties and offers potential advantages for some experimental designs as compared ...
tendency of test statistic as well as reduces the noise level in perfusion fMRI, especially at high magnetic field. ...
The authors are grateful to Kathy Tang, Marcie Rabin, and Anne Roc for their help with the experiments. ...
doi:10.1016/s1053-8119(03)00255-6
pmid:12948702
fatcat:lmvn37kyijevzisacutnwze2re
Technical aspects and utility of fMRI using BOLD and ASL
2002
Clinical Neurophysiology
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In particular, fMRI methods based on blood oxygenation level dependent (BOLD) contrast and arterial spin labeling (ASL) perfusion contrast have enabled imaging of changes in blood oxygenation and cerebral ...
This article reviews the biophysical bases and methodologies of fMRI and its applications to the clinical neurosciences, with emphasis on the spatiotemporal resolution of fMRI and its coupling with neurophysiology ...
Acknowledgements Grant support: NS37488, MH59934, and HD39621. ...
doi:10.1016/s1388-2457(02)00038-x
pmid:11976042
fatcat:7d6aw4iizfh3lmy53fjadpnqeu
Sub-millimetre resolution laminar fMRI using Arterial Spin Labelling in humans at 7 T
2021
PLoS ONE
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We observed the characteristic BOLD amplitude increase towards the superficial laminae, and, in apparent discrepancy, the relative perfusion profile shows a decrease of the amplitude and the absolute perfusion ...
This study demonstrates that laminar perfusion fMRI in humans is feasible at 7 T and that caution must be exercised when interpreting BOLD signal laminar profiles as direct representation of the cortical ...
Acknowledgments All data were acquired at the Scannexus B.V. facilities, Maastricht, The Netherlands. ...
doi:10.1371/journal.pone.0250504
pmid:33901230
pmcid:PMC8075193
fatcat:4u24nbmpf5cjroxycsr2i7xuwi
Sub-Millimetre Resolution Laminar Fmri Using Arterial Spin Labelling in Humans at 7 T
[article]
2020
bioRxiv
pre-print
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We observed the characteristic BOLD amplitude increase towards the superficial laminae, and, in apparent discrepancy, the relative perfusion profile shows a decrease of the amplitude and the absolute perfusion ...
This study demonstrates that laminar perfusion fMRI in humans is feasible at 7T and that caution must be exercised when interpreting BOLD signal laminar profiles as direct representation of the cortical ...
This is expected given the differences in the detection sensitivity (i.e. 295 functional contrast-to-noise (fCNR)) between the BOLD and perfusion signals and 296 the presence of BOLD signal in pial veins ...
doi:10.1101/2020.08.22.261693
fatcat:b7bgoraa5vh6lgdqa4k4cca6xi
Towards quantification of blood-flow changes during cognitive task activation using perfusion-based fMRI
2005
NeuroImage
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Regional differences between the localization of activations and the sensitivity of p-fMRI and BOLD-fMRI were observed as, for example, in the inferior frontal sulcus and in the intraparietal sulcus. ...
Positive activations in BOLD imaging appeared in p-fMRI as negative signal changes corresponding to an enhanced transport of inverted water spins into the region of interest, i.e., increased cerebral blood ...
Acknowledgments The authors would like to thank Prof. D. Yves von Cramon for helpful discussions regarding the context of the manuscript. ...
doi:10.1016/j.neuroimage.2005.04.040
pmid:15978840
fatcat:7gi4jqvr6jafxlircayw7ovnmi
Cocoa Flavanols, Cerebral Blood Flow, Cognition, and Health: Going Forward
2006
Journal of Cardiovascular Pharmacology
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Perfusion fMRI also has reduced scanner noise level and reduced sensitivity to subject motion. 8 Figure 3 in Francis et al 4 illustrates the usefulness of arterial spin labeling MRI for tracking the temporal ...
With excellent reproducibility over long-term time periods 5,6 and minimal sensitivity to magnetic-field inhomogeneity effects, 7 perfusion fMRI is ideal for imaging the time course of flavanol-rich cocoa ...
Perfusion fMRI also has reduced scanner noise level and reduced sensitivity to subject motion. 8 Figure 3 in Francis et al 4 illustrates the usefulness of arterial spin labeling MRI for tracking the ...
doi:10.1097/00005344-200606001-00019
pmid:16794462
fatcat:7g35fmm7kbc45dfxst4yfzvwmm
BOLD indirect vs. ASL direct measurement of muscle perfusion
2005
Journal of applied physiology
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Postcontraction hyperemia measured by fMRI scaled with contraction intensity up to 60% maximal voluntary contraction. fMRI provides a noninvasive means of quantifying perfusion-related changes during and ...
Temporal changes in perfusion can be observed, as can the heterogeneity of perfusion across the muscle bed. ...
(1) , who observed that varying the repetition time did not affect the relative signal intensity change under similar, although not identical, experimental conditions. ...
doi:10.1152/japplphysiol.00012.2005
pmid:16036909
fatcat:g7x6hznzsjaljljrlrfskq6t4y
Imaging clinically relevant pain states using arterial spin labeling
2019
PAIN Reports
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This characteristic makes ASL particularly suitable to the evaluation of brain mechanisms of tonic experimental, post-surgical and ongoing/or continuously varying pain in chronic or acute pain conditions ...
(whereas BOLD fMRI is better suited to detect brain responses to short-lasting or phasic/evoked pain). ...
), relative inflexible paradigm design opportunities, cost, and the use of radiation limit its application. ...
doi:10.1097/pr9.0000000000000750
pmid:31406952
pmcid:PMC6690842
fatcat:7j4psbyqijfpdlvztoea2qgyva
Simultaneous BOLD/perfusion measurement using dual-echo FAIR and UNFAIR: sequence comparison at 1.5T and 3.0T
2001
Magnetic Resonance Imaging
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Functional MRI (fMRI) studies designed for simultaneously measuring Blood Oxygenation Level Dependent (BOLD) and Cerebral Blood Flow (CBF) signal often employ the standard Flow Alternating Inversion Recovery ...
The reduction in UNFAIR sensitivity for perfusion is attributed to increased motion sensitivity related to its higher background signal, and, T2 related losses from the use of an extra inversion pulse. ...
Medx Software support from Jeff Solomon and Ian Heaton (Sensor Systems, VA, USA) is also gratefully acknowledged. Bobbi Lewis (LDRR) is also acknowledged for technical support. ...
doi:10.1016/s0730-725x(01)00436-2
pmid:11755725
fatcat:wdycjvnalbaaraomxuwdejiwiy
On the sensitivity of the diffusion MRI signal to brain activity in response to a motor cortex paradigm
[article]
2019
arXiv
pre-print
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perfusion and free-water diffusion, then times series of the apparent diffusion coefficient (ADC-fMRI) and of the perfusion signal fraction (IVIM-fMRI) were derived. ...
ADC-fMRI provided ADC estimates sensitive to perfusion and free-water volume changes, but not to T2 and T2* changes. ...
Acknowledgements The research of A.L. is supported by VIDI Grant 639.072.411 from the Netherlands Organisation for Scientific Research (NWO). ...
arXiv:1902.05138v1
fatcat:6ntuxqivajcatnyhit4cat5jvy
Reduced susceptibility effects in perfusion fMRI with single-shot spin-echo EPI acquisitions at 1.5 tesla
2004
Magnetic Resonance Imaging
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The results demonstrate improved functional sensitivity and efficiency of the spin-echo CASL approach as compared with gradient-echo EPI techniques, and a trend of improved sensitivity as compared with ...
Arterial spin labeling (ASL) perfusion contrast is not based on susceptibility effects and can therefore be used to study brain function in regions of high static inhomogeneity. ...
Our data suggest improved functional sensitivity and efficiency of perfusion fMRI as compared with gradient-echo BOLD techniques including thin slices methods in the presence of static field inhomogeneity ...
doi:10.1016/s0730-725x(03)00210-8
pmid:14972387
fatcat:t7a2m7dbz5fihd55d45a2osxq4
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