- Review Article
- Published:
Brain imaging with portable low-field MRI
- W. Taylor Kimberly ORCID:orcid.org/0000-0002-2519-85301,
- Annabel J. Sorby-Adams ORCID:orcid.org/0000-0003-1648-38981,
- Andrew G. Webb2,
- Ed X. Wu3,
- Rachel Beekman4,
- Ritvij Bowry5,
- Steven J. Schiff6,
- Adam de Havenon7,
- Francis X. Shen8,9,
- Gordon Sze10,
- Pamela Schaefer11,
- Juan Eugenio Iglesias12,13,14,
- Matthew S. Rosen ORCID:orcid.org/0000-0002-7194-002X12 &
- …
- Kevin N. Sheth ORCID:orcid.org/0000-0003-2003-54734
Nature Reviews Bioengineeringvolume 1, pages617–630 (2023)Cite this article
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40Citations
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APublisher Correction to this article was published on 04 August 2023
This article has beenupdated
Abstract
The advent of portable, low-field MRI (LF-MRI) heralds new opportunities in neuroimaging. Low power requirements and transportability have enabled scanning outside the controlled environment of a conventional MRI suite, enhancing access to neuroimaging for indications that are not well suited to existing technologies. Maximizing the information extracted from the reduced signal-to-noise ratio of LF-MRI is crucial to developing clinically useful diagnostic images. Progress in electromagnetic noise cancellation and machine learning reconstruction algorithms from sparsek-space data as well as new approaches to image enhancement have now enabled these advancements. Coupling technological innovation with bedside imaging creates new prospects in visualizing the healthy brain and detecting acute and chronic pathological changes. Ongoing development of hardware, improvements in pulse sequences and image reconstruction, and validation of clinical utility will continue to accelerate this field. As further innovation occurs, portable LF-MRI will facilitate the democratization of MRI and create new applications not previously feasible with conventional systems.
Key points
Portable, low-field MRI (LF-MRI) has enabled scanning outside the controlled environment of a conventional MRI suite, enhancing access to neuroimaging for indications that are not well suited to existing technologies.
Advancements in electromagnetic noise cancellation and machine learning reconstruction algorithms as well as new approaches to image enhancement seek to maximize the information extracted from the reduced signal-to-noise ratio of LF-MRI.
The reduced fringe field and the transportability of LF-MR have expanded the imaging capacity for neurological conditions such as stroke, intracerebral haemorrhage, cardiac arrest, hydrocephalus and multiple sclerosis.
Hardware developments, improvements in pulse sequences and image reconstruction, and validation of clinical utility across a range of environments will continue to accelerate LF-MRI into the future.
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Change history
04 August 2023
A Correction to this paper has been published:https://doi.org/10.1038/s44222-023-00100-1
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Acknowledgements
W.T.K., J.E.I., M.S.R. and K.N.S. are funded by a National Institute of Biomedical Imaging and Bioengineering R01 (EB031114-01A1). A.J.S.-A. is funded by the Fulbright Commission. A.G.W. is supported by an ERC Advanced Grant (101021218, PASMAR), an NWO-Open Technology grant (18981), and an NWO Stevin Prijs. E.X.W. is supported by Hong Kong Research Grant Council (R7003-19, HKU17112120, HKU17127121 and HKU17127022) and Lam Woo Foundation. F.X.S work is supported by NIH/NIMH grant RF1MH123698 on “Highly Portable and Cloud-Enabled Neuroimaging Research: Confronting Ethics in Field Research with New Populations.” The content is solely the responsibility of the authors and does not necessarily represent the official views of NIMH or NIH. S.J.S. is supported by NIH Director’s Transformative Award (1R01AI145057), and NIH grants (2R01HD085853-07, 1R01HD096693-01, 1U01NS107486 and 1UG3NS123307). J.E.I. is funded by Alzheimer’s Research UK (ARUK-IRG2019A-003), NIH BRAIN Initiative (1RF1MH123195, 1UM1MH130981) and NIH grant (1R01AG07098). M.S.R. acknowledges the gracious support of the Kiyomi and Ed Baird MGH Research Scholar Award. All other co-authors report no relevant disclosures or funding.
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Authors and Affiliations
Department of Neurology and the Center for Genomic Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
W. Taylor Kimberly & Annabel J. Sorby-Adams
Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands
Andrew G. Webb
Laboratory of Biomedical Imaging and Signal Processing, Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China
Ed X. Wu
Division of Neurocritical Care and Emergency Neurology, Department of Neurology, Yale New Haven Hospital and Yale School of Medicine, Yale Center for Brain & Mind Health, New Haven, CT, USA
Rachel Beekman & Kevin N. Sheth
Departments of Neurosurgery and Neurology, McGovern Medical School, University of Texas Health Neurosciences, Houston, TX, USA
Ritvij Bowry
Department of Neurosurgery, Yale School of Medicine, New Haven, CT, USA
Steven J. Schiff
Division of Vascular Neurology, Department of Neurology, Yale New Haven Hospital and Yale School of Medicine, New Haven, CT, USA
Adam de Havenon
Harvard Medical School Center for Bioethics, Harvard law School, Boston, MA, USA
Francis X. Shen
Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
Francis X. Shen
Department of Radiology, Yale New Haven Hospital and Yale School of Medicine, New Haven, CT, USA
Gordon Sze
Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
Pamela Schaefer
Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
Juan Eugenio Iglesias & Matthew S. Rosen
Centre for Medical Image Computing, University College London, London, UK
Juan Eugenio Iglesias
Computer Science and AI Laboratory, Massachusetts Institute of Technology, Boston, MA, USA
Juan Eugenio Iglesias
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Kimberly, W.T., Sorby-Adams, A.J., Webb, A.G.et al. Brain imaging with portable low-field MRI.Nat Rev Bioeng1, 617–630 (2023). https://doi.org/10.1038/s44222-023-00086-w
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