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Improving the sensitivity of spin-echo fMRI at 3T by highly accelerated acquisitions

Antonia Barghoorn, Bruno Riemenschneider, Jürgen Hennig, Pierre LeVan
2021 Magnetic Resonance in Medicine  
However, at 3T, the majority of blood oxygenation level-dependent (BOLD) fMRI experiments are performed using T 2 ∗ -weighted GE sequences because of their superior sensitivity compared to SE-fMRI.  ...  For the investigation of functional connectivity, additional resting-state data were acquired for 5 minutes and a seed-based correlation analysis using Stanford's FIND (Functional Imaging in Neuropsychiatric  ...  The relative blood oxygenation-level-dependent (BOLD) signal changes are similar for all sequences because they all sample the same signal, although there are clear differences in their respective noise  ... 
doi:10.1002/mrm.28715 pmid:33624352 fatcat:vdafsvxmmned7mk65srtkplc2e

Biophysical and Physiological Origins of Blood Oxygenation Level-Dependent fMRI Signals

Seong-Gi Kim, Seiji Ogawa
2012 Journal of Cerebral Blood Flow and Metabolism  
After its discovery in 1990, blood oxygenation level-dependent (BOLD) contrast in functional magnetic resonance imaging (fMRI) has been widely used to map brain activation in humans and animals.  ...  dependence of stimulus-evoked BOLD signals on baseline physiology, and (8) basis of resting-state BOLD fluctuations.  ...  Acknowledgements The authors thank colleagues at the University of Pittsburgh, especially Alberto Vazquez for providing unpublished images and Kristy Hendrich for proofreading and providing critical comments  ... 
doi:10.1038/jcbfm.2012.23 pmid:22395207 pmcid:PMC3390806 fatcat:ysnuzc5tjrbkhn34p2ar22flda

Resting-State BOLD MRI for Perfusion and Ischemia

Hannes Kroll, Greg Zaharchuk, Thomas Christen, Jeremy J. Heit, Michael Iv
2017 Topics in Magnetic Resonance Imaging (TMRI)  
Advanced imaging techniques including CT angiography, CT perfusion, MR angiography, MR with diffusion-and perfusion-weighted imaging, and, more recently, resting-state BOLD (Blood Oxygen Level Dependent  ...  ) functional MRI (rs-fMRI) are increasingly used to evaluate patients with acute ischemic stroke.  ...  In addition, JH is supported by the Radiological Society of North America Research Scholar Award RSCH1610.  ... 
doi:10.1097/rmr.0000000000000119 pmid:28277456 pmcid:PMC5380475 fatcat:kfaofmuijvabhohaibwevzi244

Functional cerebral blood volume mapping with simultaneous multi-slice acquisition

Laurentius Huber, Dimo Ivanov, Maria Guidi, Robert Turner, Kâmil Uludağ, Harald E. Möller, Benedikt A. Poser
2016 NeuroImage  
measurements of blood volume responses. 31 Blood-volume-weighted VASO and gradient echo blood oxygenation level-dependent (GE-32 BOLD) data were acquired in humans at 7 T with a 32-channel head coil.  ...  Magn Reson Med 5, M.J., Hoogduin, H., van Zijl, P.C.M., Jezzard, P., Luijten, P.R., Hendrikse, J., 2010 Blood 6 oxygenation level-dependent (BOLD) total and extravascular signal changes and ΔR2* in 7 human  ... 
doi:10.1016/j.neuroimage.2015.10.082 pmid:26522423 fatcat:24freuo6onaofhjbjeyl7h4fdu

Practical aspects of functional MRI (NMR Task Group #8)

Ronald R. Price, Jerry Allison, Richard J. Massoth, Geoffrey D. Clarke, Dick J. Drost
2002 Medical Physics (Lancaster)  
Functional MR imaging ͑fMRI͒ based upon the Blood Oxygen Level Dependent ͑BOLD͒ effect is currently an important new tool for understanding basic brain function and specifically allowing the correlation  ...  Our purpose in this report is to provide, in addition to basic principles, an insight into the aspects of BOLD imaging, which may be used by the medical physicist to assist in the implement of fMRI procedures  ...  The work of Ogawa, Lee, and co-workers, 2, 5 showed that in high-field, high-resolution MRI, the image contrast surrounding blood vessels is related to the level of blood oxygenation in the vessels.  ... 
doi:10.1118/1.1494990 pmid:12201436 fatcat:mj5wpmzu5vcsnj6awk77vcgek4

Functional magnetic resonance imaging of the visual system

Atsushi Miki, Grant T. Liu, Edward J. Modestino, Chia-Shang J. Liu, Gabrielle R. Bonhomme, Cristian M. Dobre, John C. Haselgrove
2001 Current Opinion in Ophthalmology  
Functional magnetic resonance imaging and the blood oxygenation level dependent contrast method In most fMRI studies, neuronal activity is detected using the blood oxygenation level dependent (BOLD) contrast  ...  Functional magnetic resonance imaging (fMRI), which is a technique useful for non-invasive mapping of brain function, is well suited for studying the visual system.  ...  Functional magnetic resonance imaging and the blood oxygenation level dependent contrast method In most fMRI studies, neuronal activity is detected using the blood oxygenation level dependent (BOLD) contrast  ... 
doi:10.1097/00055735-200112000-00007 pmid:11734682 fatcat:xia73ymworejffiqorbbz4diiu

Clinical implications of skeletal muscle blood-oxygenation-level-dependent (BOLD) MRI

Sasan Partovi, Sasan Karimi, Bjoern Jacobi, Anja-Carina Schulte, Markus Aschwanden, Lisa Zipp, John K. Lyo, Christof Karmonik, Matthias Müller-Eschner, Rolf W. Huegli, Georg Bongartz, Deniz Bilecen
2012 Magnetic Resonance Materials in Physics, Biology and Medicine  
Blood-oxygenation-level-dependent (BOLD) contrast in magnetic resonance (MR) imaging of skeletal muscle mainly depends on changes of oxygen saturation in the microcirculation.  ...  BOLD imaging combines the advantages of MR imaging, i.e., high spatial resolution, no exposure to ionizing radiation, with functional information of local microvascular perfusion.  ...  Introduction Blood-oxygenation-level-dependent (BOLD) magnetic resonance imaging (MRI) was introduced in functional neuroimaging studies in 1990 [1] .  ... 
doi:10.1007/s10334-012-0306-y pmid:22374263 fatcat:2onoenznunaobbeywyfwwumqtm

Functional Magnetic Resonance Imaging: From Acquisition to Application

Gail Yarmish, Michael L. Lipton
2016 Einstein Journal of Biology and Medicine  
The most common fMRI method detects blood oxygen level dependent (BOLD) contrast.  ...  The small, but detectable, change in magnetics resonance signal intensity is due to the sensitivity of magnetic resonance (MR) images to the paramagnetic deoxygenated state of hemoglobin that is the basis  ...  This is referred to as "Blood Oxygen Level Dependent" or "BOLD" contrast.  ... 
doi:10.23861/ejbm200320103 fatcat:5gwnzjxgqzf77njiv3qgqhy65e

Physiological basis and image processing in functional magnetic resonance imaging: neuronal and motor activity in brain

Rakesh Sharma, Avdhesh Sharma
2004 BioMedical Engineering OnLine   retracted
Functional magnetic resonance imaging (fMRI) is recently developing as imaging modality used for mapping hemodynamics of neuronal and motor event related tissue blood oxygen level dependence (BOLD) in  ...  Segmentation algorithms provide brain surface-based analysis, automated anatomical labeling of cortical fields in magnetic resonance data sets based on oxygen metabolic state.  ...  High resolution, noninvasive neural activity by a blood oxygen level dependent signal has tremendous potentials for assessing the neurological status and neurosurgical risk [1] [2] [3] [4] .  ... 
doi:10.1186/1475-925x-3-13 pmid:15125779 pmcid:PMC419711 fatcat:dcn2cgkgyrfspboticb2qyswmy

Advanced Magnetic Resonance Imaging in Epilepsy

Heath Pardoe, Ruben Kuzniecky
2014 US Neurology  
Functional MRI (fMRI) methods including electroencephalography (EEG)-fMRI and resting state imaging have been used to study network activity, such as language and memory in surgical candidates.  ...  Magnetic resonance imaging (MRI) is the most commonly used noninvasive imaging modality for epilepsy diagnosis, etiologic classification, and management.  ...  Statistical comparison of images is used to identify regions in which there are signal differences due to blood oxygenation; there is strong evidence that BOLD contrast corresponds to some aspects of local  ... 
doi:10.17925/usn.2014.10.02.104 fatcat:gaiqj5nrbrhtbbfpqlvvxlhxci

Magnetic resonance imaging of oscillating electrical currents

N. W. Halpern-Manners, V. S. Bajaj, T. Z. Teisseyre, A. Pines
2010 Proceedings of the National Academy of Sciences of the United States of America  
The fMRI technique is a relaxometry measurement based upon the modulation of water relaxation by oxygenated hemoglobin in regions of neuronal activity [the blood-oxygen-level-dependent (BOLD) effect] (  ...  We illustrate that remotely detected MRI permits the measurement of currents in small volumes of flowing water with high sensitivity and spatial resolution. current imaging | EEG | magnetoencephalography  ...  The fMRI technique is a relaxometry measurement based upon the modulation of water relaxation by oxygenated hemoglobin in regions of neuronal activity [the blood-oxygen-level-dependent (BOLD) effect]  ... 
doi:10.1073/pnas.1003146107 pmid:20421504 pmcid:PMC2889347 fatcat:ch2fmflxdrdvpevu3kjjh573fe

Comparison of Resting-State Brain Activation Detected by BOLD, Blood Volume and Blood Flow

Ke Zhang, Dengfeng Huang, N Jon Shah
2018 Frontiers in Human Neuroscience  
Resting-state brain activity has been widely investigated using blood oxygenation level dependent (BOLD) contrast techniques.  ...  In this study, resting-state brain activation was detected and compared using the following techniques: (a) BOLD, using a gradient-echo echo planar imaging (GE-EPI) sequence; (b) CBV-weighted signal, acquired  ...  It is possible to acquire functional signals using magnetic resonance imaging (MRI) based on blood oxygenation level dependent (BOLD) contrast, cerebral blood flow (CBF), cerebral blood volume (CBV) and  ... 
doi:10.3389/fnhum.2018.00443 pmid:30467468 pmcid:PMC6235966 fatcat:4jznjwuesbfodix6xhi5qm57oa

An echo-planar imaging sequence is superior to a steady-state free precession sequence for visual as well as quantitative assessment of cardiac magnetic resonance stress perfusion

Britt-Marie Ahlander, Eva Maret, Lars Brudin, Sven-Ake Starck, Jan Engvall
2015 Clinical Physiology and Functional Imaging  
This is the published version of a paper published in Clinical Physiology and Functional Imaging.  ...  precession sequence for visual as well as quantitative assessment of cardiac magnetic resonance stress perfusion Clinical Physiology and Functional Imaging, 37(1): 52-61  ...  Siemens Healthcare gave access to the two perfusion sequences that at the time were work in progress, WIP.  ... 
doi:10.1111/cpf.12267 pmid:26147785 fatcat:hmffumkaendufdkfwp67zfr7ni

Improvements in parallel imaging accelerated functional MRI using multiecho echo-planar imaging

Heiko Schmiedeskamp, Rexford D. Newbould, Laura J. Pisani, Stefan Skare, Gary H. Glover, Klaas P. Pruessmann, Roland Bammer
2010 Magnetic Resonance in Medicine  
Multiecho echo-planar imaging (EPI) was implemented for blood-oxygenation-level-dependent functional MRI at 1.5 T and compared to single-echo EPI with and without parallel imaging acceleration.  ...  Abstract Multiecho echo-planar imaging (EPI) was implemented for blood-oxygenation-level-dependent functional MRI at 1.5 T and compared to single-echo EPI with and without parallel imaging acceleration  ...  Grant sponsor: National Institutes of Health; Grant numbers: R01EB002711, R01NS047607, R01NS34866, P41RR09784.  ... 
doi:10.1002/mrm.22222 pmid:20373397 pmcid:PMC2906757 fatcat:nu45vfsh6rephmnirypkaxdosy

Brain–heart interactions: challenges and opportunities with functional magnetic resonance imaging at ultra-high field

Catie Chang, Erika P. Raven, Jeff H. Duyn
2016 Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences  
The vast majority of fMRI studies are based on the blood-oxygen-level-dependent (BOLD) effect [29] , by which changes in neural activity are coupled with local changes in blood flow and blood oxygenation  ...  (d) Applications of high-resolution functional magnetic resonance imaging at ultra-high field Capitalizing on recent advances in UHF imaging, a number of studies have demonstrated the ability to map features  ... 
doi:10.1098/rsta.2015.0188 pmid:27044994 pmcid:PMC4822447 fatcat:gx7xotwgjrchjlqsqd6mq5qnjm
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