7T vs. 4T: RF power, homogeneity, and signal-to-noise comparison in head images
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Signal‐to‐noise ratio (SNR), RF field (B1), and RF power requirement for human head imaging were examined at 7T and 4T magnetic field strengths. The variation in B1 magnitude was nearly twofold higher at 7T than at 4T (∼42% compared to ∼23%). The power required for a 90° pulse in the center of the head at 7T was approximately twice that at 4T. The SNR averaged over the brain was at least 1.6 times higher at 7T compared to 4T. These experimental results were consistent with calculations performed using a human head model and Maxwell's equations. Magn Reson Med 46:24–30, 2001. © 2001 Wiley‐Liss, Inc.
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Compared with lower field strengths, 7T raises image SNR and functional contrast-to-noise.
“7T provides increases in both the image SNR (Vaughan et al., 2001) and functional contrast–to-noise (Yacoub et al., 2001), compared to lower fields.”
From The WU-Minn Human Connectome Project: An overview (2013) · cites this paper as Vaughan et al., 2001
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Cites
The Finite Difference Time Domain Method for Electromagnetics
Kunz, K. S., & Luebbers, R. J. (2018) · CRC Press eBooks · doi:10.1201/9780203736708 · Cited by 2,530 · see citing works
Compilation of the Dielectric Properties of Body Tissues at RF and Microwave Frequencies.
Gabriel, C. (1996) · doi:10.21236/ada303903 · Cited by 2,108 · see citing works
The intrinsic signal-to-noise ratio in NMR imaging
Edelstein, W. A., Glover, G. H., Hardy, C. J., & Redington, R. W. (1986) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910030413 · Cited by 758 · see citing works
Snapshot flash mri. applications to t1, t2, and chemical‐shift imaging
Haase, A. (1990) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910130109 · Cited by 699 · see citing works
The principle of reciprocity in signal strength calculations?A mathematical guide
Hoult, D. I. (2000) · Concepts in Magnetic Resonance · doi:10.1002/1099-0534(2000)12:4 · Cited by 550 · see citing works
High-resolution mapping of iso-orientation columns by fMRI
Kim, D., Duong, T. Q., & Kim, S. (2000) · Nature Neuroscience · doi:10.1038/72109 · Cited by 393 · see citing works
High frequency volume coils for clinical NMR imaging and spectroscopy
Vaughan, J. T., Hetherington, H. P., Otu, J. O., Pan, J. W., & Pohost, G. M. (1994) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910320209 · Cited by 374 · see citing works
Self-citationImaging at high magnetic fields: initial experiences at 4 T.
Uǧurbil, K., Garwood, M., Ellermann, J., Hendrich, K. S., Hinke, R. M., Hu, X. P., Kim, S. G., Menon, R. S., Merkle, H., & Ogawa, S. (1993) · PubMed · Cited by 282 · see citing works
Self-citationSAR and B 1 field distributions in a heterogeneous human head model within a birdcage coil
Collins, C. M., Li, S., & Smith, M. B. H. (1998) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910400610 · Cited by 272 · see citing works
Self-citationKim, S., Rostrup, E., Larsson, H. B. W., Ogawa, S., & Paulson, O. B. (1999) · Magnetic Resonance in Medicine · doi:10.1002/(sici)1522-2594(199906)41:6 · Cited by 267 · see citing works
Röschmann, P. (1987) · Medical Physics · doi:10.1118/1.595995 · Cited by 233 · see citing works
Resolution Improvements inin Vivo1H NMR Spectra with Increased Magnetic Field Strength
Rolf Gruetter, A., Weisdorf, S., Rajanayagan, V., Terpstra, M., Merkle, H., Truwit, C. L., Garwood, M., Nyberg, S. L., & Uǧurbil, K. (1998) · Journal of Magnetic Resonance · doi:10.1006/jmre.1998.1542 · Cited by 195 · see citing works
Self-citationLocalized in vivo 13C-NMR of Glutamate Metabolism in the Human Brain: Initial Results at 4 Tesla
Rolf Gruetter, A., Seaquist, E. R., Kim, S., & Uǧurbil, K. (1998) · Developmental Neuroscience · doi:10.1159/000017334 · Cited by 194 · see citing works
Functional mapping in the human brain using high magnetic fields
Uǧurbil, K., Hu, X. P., Chen, W., Zhu, X.-H., Kim, S., & Georgopoulos, A. P. (1999) · Philosophical Transactions of the Royal Society B Biological Sciences · doi:10.1098/rstb.1999.0474 · Cited by 153 · see citing works
Proton nuclear magnetic resonance spectroscopic imaging of human temporal lobe epilepsy at 4.1 T
Hetherington, H. P., Kuzniecky, R., Pan, J. W., et al. (1995) · Annals of Neurology · doi:10.1002/ana.410380309 · Cited by 128 · see citing works
In vivo magnetic resonance imaging and spectroscopy of humans with a 4 t whole‐body magnet
Barfuss, H., Fischer, H., Hentschel, D., Ladebeck, R., Oppelt, A., Wittig, R., Duerr, W., & Oppelt, R. (1990) · NMR in Biomedicine · doi:10.1002/nbm.1940030106 · Cited by 119 · see citing works
Texture analysis of spinal cord pathology in multiple sclerosis
Mathias, J. M., Tofts, P. S., & Losseff, N. A. (1999) · Magnetic Resonance in Medicine · doi:10.1002/(sici)1522-2594(199911)42:5 · Cited by 98 · see citing works
Pfeuffer, J., Tk�, I., Choi, I.-Y., Merkle, H., urbil, K. U., Garwood, M., & Rolf Gruetter, A. (1999) · Infoscience (Ecole Polytechnique Fédérale de Lausanne) · doi:10.1002/(sici)1522-2594(199906)41:6<1077::aid-mrm1>3.0.co;2 · Cited by 94 · see citing works
Self-citationObservation of resolved glucose signals in 1H NMR spectra of the human brain at 4 Tesla
Rolf Gruetter, A., Garwood, M., Uǧurbil, K., & Seaquist, E. R. (1996) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910360102 · Cited by 93 · see citing works
Self-citationPunwani, S., Ordidge, R. J., Cooper, C. E., Amess, P., & Clemence, M. (1998) · NMR in Biomedicine · doi:10.1002/(sici)1099-1492(199810)11:6 · Cited by 74 · see citing works
High resolution neuroimaging at 4.1 T
Pan, J. W., Vaughan, J. T., Kuzniecky, R., et al. (1995) · Magnetic Resonance Imaging · doi:10.1016/0730-725x(95)02002-b · Cited by 56 · see citing works
Self-citation3D 31P Spectroscopic Imaging of the Human Heart at 4.1 T
Hetherington, H. P., Luney, D., Vaughan, J. T., et al. (1995) · Magnetic Resonance in Medicine · doi:10.1002/mrm.1910330318 · Cited by 51 · see citing works
Self-citationfMRI assessment of hemispheric language dominance using a simple inner speech paradigm
Baciu, M. V., Rubin, C., Décorps, M., & Segebarth, C. M. (1999) · NMR in Biomedicine · doi:10.1002/(sici)1099-1492(199908)12:5 · Cited by 36 · see citing works
"Letter to the editor": Comment.
Estroff, S. E. (1984) · Psychosocial Rehabilitation Journal · doi:10.1037/h0099650 · Cited by 26 · see citing works
T1- and T2-Weighted Imaging at 8 Tesla
Kangarlu, A., Abduljalil, A., & Robitaille, P.-M. L. (1999) · Journal of Computer Assisted Tomography · doi:10.1097/00004728-199911000-00010 · Cited by 20 · see citing works
Flagged first, then by citations
Research works printed but not linked: 4
- Ugurbil K, Garwood M, Ellermann J, Hendrich K, Hinke R, Hu X, Kim S-G, Menon R, Merkle H, Ogawa S. Imaging at high magnetic fields: initial experiences at 4T. Magn Reson Q 1993;9:259 -277.
- Pan JW, Vaughan JT, Kuzniecky RI, Pohost GM, Hetherington HP. High resolution neuroimaging at 4.1T. Magn Reson Imaging 1995;13:915- 921.
- Lee S-P, Silva AC, Ugurbil K, Kim S-G. Diffusion weighted spin echo fMRI at 9.4 T: microvascular/tissue contribution to BOLD signal changes. Magn Reson Med 1999;42:919 -928.
- Robitaille PM, Abduljalil AM, Kangarlu A, Zhang X, Yu Y, Burgess R, Bair S, Noa P, Yang L, Zhu H, Palmer B, Jiang Z, Chakeres DM, Spigos D. Human magnetic resonance imaging at 8 T. NMR Biomed 1998;11: 263-265.
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Van Essen, D. C., Smith, S. M., Barch, D. M., Behrens, T. E. J., Yacoub, E., & Ugurbil, K. (2013) · NeuroImage · doi:10.1016/j.neuroimage.2013.05.041 · Cited by 5,651 · see citing works
Self-citationResting-state fMRI in the human connectome project
Smith, S. M., Beckmann, C. F., Andersson, J., Auerbach, E. J., Bijsterbosch, J., Douaud, G., Duff, E., Feinberg, D. A., Griffanti, L., Harms, M. P., et al. (2013) · NeuroImage · doi:10.1016/j.neuroimage.2013.05.039 · Cited by 1,502 · see citing works
Moeller, S., Yacoub, E., Olman, C. A., Auerbach, E., Strupp, J., Harel, N., & Uğurbil, K. (2010) · Magnetic Resonance in Medicine · doi:10.1002/mrm.22361 · Cited by 1,586 · see citing works
Goebel, R., Esposito, F., & Formisano, E. (2006) · Human Brain Mapping · doi:10.1002/hbm.20249 · Cited by 1,053 · see citing works
Self-citationUğurbil, K., Xu, J., Auerbach, E. J., Moeller, S., Vu, A. T., Duarte-Carvajalino, J. M., Lenglet, C., Wu, X., Schmitter, S., Van de Moortele, P. F., et al. (2013) · NeuroImage · doi:10.1016/j.neuroimage.2013.05.012 · Cited by 812 · see citing works
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Setsompop, K., Kimmlingen, R., Eberlein, E., Witzel, T., Cohen-Adad, J., McNab, J. A., Keil, B., Tisdall, M. D., Hoecht, P., Dietz, P., et al. (2013) · NeuroImage · doi:10.1016/j.neuroimage.2013.05.078 · Cited by 545 · see citing works
Gard, T., Holzel, B. K., Sack, A. T., Hempel, H., Lazar, S. W., Vaitl, D., & Ott, U. (2012) · Cerebral Cortex · doi:10.1093/cercor/bhr352 · Cited by 276 · see citing works
Mangia, S., Giove, F., Tkáč, I., Logothetis, N. K., Henry, P.-G., Olman, C. A., Maraviglia, B., Di Salle, F., & Uğurbil, K. (2009) · Journal of Cerebral Blood Flow & Metabolism · doi:10.1038/jcbfm.2008.134 · Cited by 161 · see citing works
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- Authors
- Vaughan, J. T., Garwood, M., Collins, C. M., Liu, W., DelaBarre, L., Adriany, G., Andersen, P., Merkle, H., Goebel, R., Smith, M. B., & Ugurbil, K.
- Affiliations
- University of Minnesota (US)
- Pennsylvania State University (US)
- Maastricht University (NL)
- Corresponding author
- Vaughan, J.T.
- Venue
- Magnetic Resonance in Medicine
- Publisher
- Wiley
- Published
- 2001-07
- Volume
- 46
- Issue
- 1
- Pages
- 24-30
- ISSN
- 0740-3194 (ISSN-L)
- 1522-2594
- OpenAlex
- W2120836547
- Cited by
- 890
- References
- 25
- Citations by year
- 2026: 15 · 2025: 27 · 2024: 29 · 2023: 28 · 2022: 38 · 2021: 36 · 2020: 39 · 2019: 33 · 2018: 49 · 2017: 37 · 2016: 48 · 2015: 53 · 2014: 41 · 2013: 68 · 2012: 41
- FWCI
- 14.76
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Magnetic Resonance in Medicine (publishedVersion)
- PubMed (publishedVersion)
- Funders
- W. M. Keck Foundation
- University of Minnesota
- National Institutes of Health (5r01ca064338-04, RR08079)
- National Cancer Institute (R01CA076535, CA-64338, CA 76535)
- National Center for Research Resources (RR 08079, P41RR008079)
- Topics
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Advanced MRI Techniques and Applications
- Physical Sciences › Chemistry › Spectroscopy › Advanced NMR Techniques and Applications
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Advanced Neuroimaging Techniques and Applications
- Keywords
- 7T MRI, RF power, B1 field homogeneity, signal-to-noise ratio, human head imaging, human head model, Maxwell's equations, ultra-high field MRI
- MeSH terms
- Brain, Calibration, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Radio Waves
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