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Lu KY, Lin FS, Lin CS, Lao HC. Percutaneous cervical cordotomy for managing refractory pain in a patient with a Pancoast tumor: A case report. World J Clin Cases 2024; 12:4770-4776. [DOI: 10.12998/wjcc.v12.i21.4770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 05/15/2024] [Accepted: 05/30/2024] [Indexed: 06/30/2024] Open
Abstract
BACKGROUND According to the World Health Organization analgesic ladder, cancer-related pain generally begins with pharmacotherapy in a stepwise approach. Nevertheless, some patients continue to experience poorly controlled pain despite medications, particularly when considering adverse effects and self-care quality. Percutaneous cervical cordotomy is an alternative interventional procedure for unremitting unilateral intractable cancer-related pain.
CASE SUMMARY The patient was diagnosed with lung cancer with destruction of the brachial plexus and ribs. For 2 mo, the patient experienced progressive severe weakness and pain in the right upper extremity. Notably, the pain intensity reached an extreme level, particularly when lying supine, even under heavy sedation. This heightened pain response posed a significant challenge; as a result, the patient was unable to undergo further evaluation through magnetic resonance imaging. Ultimately, he underwent percutaneous cervical cordotomy for symptom relief, resulting in complete resolution of right arm pain. After a 3-mo follow-up, the pain did not recur, and only a flurbiprofen local patch was required for mild scapular tightness.
CONCLUSION Cordotomy, under careful patient selection, appears to enhance the quality of life of patients with unilateral cancer-related pain.
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Affiliation(s)
- Kuan-Yu Lu
- Department of Anesthesiology, MacKay Memorial Hospital, Taipei 10449, Taiwan
| | - Feng-Sheng Lin
- Department of Anesthesiology, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Chia-Shiang Lin
- Department of Anesthesiology, MacKay Memorial Hospital, Taipei 10449, Taiwan
- Department of Anesthesiology, Shuang-Ho Hospital, Taipei 23561, Taiwan
| | - Hsuan-Chih Lao
- Department of Anesthesiology, MacKay Memorial Hospital, Taipei 10449, Taiwan
- Institute of Brain Science, College of Medicine, National Yang Ming Chiao Tung University, Taipei 11203, Taiwan
- Department of Medicine, MacKay Medical College, Taipei 23245, Taiwan
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Seifert AC, Xu J, Kong Y, Eippert F, Miller KL, Tracey I, Vannesjo SJ. Thermal stimulus task fMRI in the cervical spinal cord at 7 Tesla. Hum Brain Mapp 2024; 45:e26597. [PMID: 38375948 PMCID: PMC10877664 DOI: 10.1002/hbm.26597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 12/15/2023] [Accepted: 01/04/2024] [Indexed: 02/21/2024] Open
Abstract
Although functional magnetic resonance imaging (fMRI) is widely applied in the brain, fMRI of the spinal cord is more technically demanding. Proximity to the vertebral column and lungs results in strong spatial inhomogeneity and temporal fluctuations in B0 . Increasing field strength enables higher spatial resolution and improved sensitivity to blood oxygenation level-dependent (BOLD) signal, but amplifies the effects of B0 inhomogeneity. In this work, we present the first task fMRI in the spinal cord at 7 T. Further, we compare the performance of single-shot and multi-shot 2D echo-planar imaging (EPI) protocols, which differ in sensitivity to spatial and temporal B0 inhomogeneity. The cervical spinal cords of 11 healthy volunteers were scanned at 7 T using single-shot 2D EPI at 0.75 mm in-plane resolution and multi-shot 2D EPI at 0.75 and 0.6 mm in-plane resolutions. All protocols used 3 mm slice thickness. For each protocol, the BOLD response to 13 10-s noxious thermal stimuli applied to the right thumb was acquired in a 10-min fMRI run. Image quality, temporal signal to noise ratio (SNR), and BOLD activation (percent signal change and z-stat) at both individual- and group-level were evaluated between the protocols. Temporal SNR was highest in single-shot and multi-shot 0.75 mm protocols. In group-level analyses, activation clusters appeared in all protocols in the ipsilateral dorsal quadrant at the expected C6 neurological level. In individual-level analyses, activation clusters at the expected level were detected in some, but not all subjects and protocols. Single-shot 0.75 mm generally produced the highest mean z-statistic, while multi-shot 0.60 mm produced the best-localized activation clusters and the least geometric distortion. Larger than expected within-subject segmental variation of BOLD activation along the cord was observed. Group-level sensory task fMRI of the cervical spinal cord is feasible at 7 T with single-shot or multi-shot EPI. The best choice of protocol will likely depend on the relative importance of sensitivity to activation versus spatial localization of activation for a given experiment. PRACTITIONER POINTS: First stimulus task fMRI results in the spinal cord at 7 T. Single-shot 0.75 mm 2D EPI produced the highest mean z-statistic. Multi-shot 0.60 mm 2D EPI provided the best-localized activation and least distortion.
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Affiliation(s)
- Alan C. Seifert
- Biomedical Engineering and Imaging InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Department of Diagnostic, Molecular, and Interventional RadiologyIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
- Graduate School of Biomedical SciencesIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Junqian Xu
- Department of RadiologyBaylor College of MedicineHoustonTexasUSA
- Department of PsychiatryBaylor College of MedicineHoustonTexasUSA
| | - Yazhuo Kong
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Institute of PsychologyChinese Academy of SciencesBeijingChina
| | - Falk Eippert
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Max Planck Research Group Pain PerceptionMax Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
| | - Karla L. Miller
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Irene Tracey
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - S. Johanna Vannesjo
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Department of PhysicsNorwegian University of Science and Technology (NTNU)TrondheimNorway
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Seifert AC, Xu J, Kong Y, Eippert F, Miller KL, Tracey I, Vannesjo SJ. Thermal Stimulus Task fMRI in the Cervical Spinal Cord at 7 Tesla. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.31.526451. [PMID: 36778391 PMCID: PMC9915652 DOI: 10.1101/2023.01.31.526451] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE Although functional MRI is widely applied in the brain, fMRI of the spinal cord is more technically demanding. Proximity to the vertebral column and lungs results in strong spatial inhomogeneity and temporal fluctuations in B0. Increasing field strength enables higher spatial resolution and improved sensitivity to BOLD signal, but amplifies the effects of B0 inhomogeneity. In this work, we present the first stimulus task fMRI in the spinal cord at 7 T. Further, we compare the performance of single-shot and multi-shot 2D EPI protocols, as they differ in sensitivity to spatial and temporal B0 inhomogeneity. METHODS The cervical spinal cords of 11 healthy volunteers were scanned at 7 T using single-shot 2D EPI at 0.75 mm in-plane resolution and multi-shot 2D EPI at 0.75 and 0.6 mm in-plane resolutions. For each protocol, the BOLD response to thirteen 10-second noxious thermal stimuli applied to the right thumb was acquired in a 10-minute fMRI run. Image quality, temporal SNR, and BOLD activation (percent signal change and z-stat) at both individual- and group-level were evaluated between the protocols. RESULTS Temporal SNR was highest in single-shot and multi-shot 0.75 mm protocols. In group-level analyses, activation clusters appeared in all protocols in the ipsilateral dorsal quadrant at the expected C6 neurological level. In individual-level analyses, activation clusters at the expected level were detected in some, but not all subjects and protocols. Single-shot 0.75 mm generally produced the highest mean z-statistic, while multi-shot 0.60 mm produced the best-localized activation clusters and the least geometric distortion. Larger than expected within-subject segmental variation of BOLD activation along the cord was observed. CONCLUSION Group-level sensory task fMRI of the cervical spinal cord is feasible at 7 T with single-shot or multi-shot EPI. The best choice of protocol will likely depend on the relative importance of sensitivity to activation versus spatial localization of activation for a given experiment.
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Rios NL, Gilbert KM, Papp D, Cereza G, Foias A, Rangaprakash D, May MW, Guerin B, Wald LL, Keil B, Stockmann JP, Barry RL, Cohen-Adad J. An 8-channel Tx dipole and 20-channel Rx loop coil array for MRI of the cervical spinal cord at 7 Tesla. NMR IN BIOMEDICINE 2023; 36:e5002. [PMID: 37439129 PMCID: PMC10733907 DOI: 10.1002/nbm.5002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/10/2023] [Accepted: 06/15/2023] [Indexed: 07/14/2023]
Abstract
The quality of cervical spinal cord images can be improved by the use of tailored radiofrequency (RF) coil solutions for ultrahigh field imaging; however, very few commercial and research 7-T RF coils currently exist for the spinal cord, and in particular, those with parallel transmission (pTx) capabilities. This work presents the design, testing, and validation of a pTx/Rx coil for the human neck and cervical/upper thoracic spinal cord. The pTx portion is composed of eight dipoles to ensure high homogeneity over this large region of the spinal cord. The Rx portion is made up of twenty semiadaptable overlapping loops to produce high signal-to-noise ratio (SNR) across the patient population. The coil housing is designed to facilitate patient positioning and comfort, while also being tight fitting to ensure high sensitivity. We demonstrate RF shimming capabilities to optimize B1 + uniformity, power efficiency, and/or specific absorption rate efficiency. B1 + homogeneity, SNR, and g-factor were evaluated in adult volunteers and demonstrated excellent performance from the occipital lobe down to the T4-T5 level. We compared the proposed coil with two state-of-the-art head and head/neck coils, confirming its superiority in the cervical and upper thoracic regions of the spinal cord. This coil solution therefore provides a convincing platform for producing the high image quality necessary for clinical and research scanning of the upper spinal cord.
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Affiliation(s)
- Nibardo Lopez Rios
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Kyle M. Gilbert
- Centre for Functional and Metabolic Mapping, The University of Western Ontario, London, ON, Canada
| | - Daniel Papp
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Gaspard Cereza
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - Alexandru Foias
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
| | - D. Rangaprakash
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Markus W. May
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany
- High Field and Hybrid MR Imaging, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Bastien Guerin
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Boris Keil
- Institute of Medical Physics and Radiation Protection, University of Applied Sciences Mittelhessen, Giessen, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Marburg, Philipps University of Marburg, Marburg, Germany
| | - Jason P. Stockmann
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Robert L. Barry
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montréal, QC, Canada
- Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
- Mila – Quebec AI Institute, Montreal, QC, Canada
- Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, QC, Canada
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Testud B, Fabiani N, Demortière S, Mchinda S, Medina NL, Pelletier J, Guye M, Audoin B, Stellmann JP, Callot V. Contribution of the MP2RAGE 7T Sequence in MS Lesions of the Cervical Spinal Cord. AJNR Am J Neuroradiol 2023; 44:1101-1107. [PMID: 37562829 PMCID: PMC10494945 DOI: 10.3174/ajnr.a7964] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 07/06/2023] [Indexed: 08/12/2023]
Abstract
BACKGROUND AND PURPOSE The detection of spinal cord lesions in patients with MS is challenging. Recently, the 3D MP2RAGE sequence demonstrated its usefulness at 3T. Benefiting from the high spatial resolution provided by ultra-high-field MR imaging systems, we aimed to evaluate the contribution of the 3D MP2RAGE sequence acquired at 7T for the detection of MS lesions in the cervical spine. MATERIALS AND METHODS Seventeen patients with MS participated in this study. They were examined at both 3T and 7T. The MR imaging examination included a Magnetic Imaging in MS (MAGNIMS) protocol with an axial T2*-WI gradient recalled-echo sequence ("optimized MAGNIMS protocol") and a 0.9-mm isotropic 3D MP2RAGE sequence at 3T, as well as a 0.7-mm isotropic and 0.3-mm in-plane-resolution anisotropic 3D MP2RAGE sequences at 7T. Each data set was read by a consensus of radiologists, neurologists, and neuroscientists. The number of lesions and their topography, as well as the visibility of the lesions from one set to another, were carefully analyzed. RESULTS A total of 55 lesions were detected. The absolute number of visible lesions differed among the 4 sequences (linear mixed effect ANOVA, P = .020). The highest detection was observed for the two 7T sequences with 51 lesions each (92.7% of the total). The optimized 3T MAGNIMS protocol and the 3T MP2RAGE isotropic sequence detected 41 (74.5%) and 35 lesions (63.6%), respectively. CONCLUSIONS The 7T MP2RAGE sequences detected more lesions than the 3T sets. Isotropic and anisotropic acquisitions performed comparably. Ultra-high-resolution sequences obtained at 7T improve the identification and delineation of lesions of the cervical spinal cord in MS.
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Affiliation(s)
- B Testud
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - N Fabiani
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - S Demortière
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
- Department of Neurology (S.D., J.P., B.A.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - S Mchinda
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - N L Medina
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - J Pelletier
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
- Department of Neurology (S.D., J.P., B.A.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - M Guye
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - B Audoin
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
- Department of Neurology (S.D., J.P., B.A.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - J P Stellmann
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - V Callot
- From the Center for Magnetic Resonance in Biology and Medicine (B.T., N.F., S.D., S.M., N.L.M., J.P., M.G., B.A., J.P.S., V.C.), Aix-Marseille University, Centre national de la recherche scientifique, Marseille, France
- Assistance Publique-Hopitaux de Marseille (B.T., N.F., S.D., S.M., N.L.M., J,P., M.G., B.A., J.P.S., V.C.), Hôpital Universitaire Timone, CEMEREM, Marseille, France
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Mahmud SZ, Denney TS, Bashir A. Feasibility of spinal cord imaging at 7 T using rosette trajectory with magnetization transfer preparation and compressed sensing. Sci Rep 2023; 13:8777. [PMID: 37258697 DOI: 10.1038/s41598-023-35853-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/24/2023] [Indexed: 06/02/2023] Open
Abstract
MRI is a valuable diagnostic tool to investigate spinal cord (SC) pathology. SC MRI can benefit from the increased signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) at ultra-high fields such as 7 T. However, SC MRI acquisitions with routine Cartesian readouts are prone to image artifacts caused by physiological motion. MRI acquisition techniques with non-Cartesian readouts such as rosette can help reduce motion artifacts. The purpose of this study was to demonstrate the feasibility of high-resolution SC imaging using rosette trajectory with magnetization transfer preparation (MT-prep) and compressed sensing (CS) at 7 T. Five healthy volunteers participated in the study. Images acquired with rosette readouts demonstrated reduced motion artifacts compared to the standard Cartesian readouts. The combination of multi-echo rosette-readout images improved the CNR by approximately 50% between the gray matter (GM) and white matter (WM) compared to single-echo images. MT-prep images showed excellent contrast between the GM and WM with magnetization transfer ratio (MTR) and cerebrospinal fluid normalized MT signal (MTCSF) = 0.12 ± 0.017 and 0.74 ± 0.013, respectively, for the GM; and 0.18 ± 0.011 and 0.58 ± 0.009, respectively, for the WM. Under-sampled acquisition using rosette readout with CS reconstruction demonstrated up to 6 times faster scans with comparable image quality as the fully-sampled acquisition.
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Affiliation(s)
- Sultan Z Mahmud
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA
| | - Thomas S Denney
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA
| | - Adil Bashir
- Department of Electrical and Computer Engineering, Auburn University, Auburn, AL, USA.
- Auburn University MRI Research Center, Auburn University, Auburn, AL, USA.
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Rios NL, Gilbert KM, Papp D, Cereza G, Foias A, Rangaprakash D, May MW, Guerin B, Wald LL, Keil B, Stockmann JP, Barry RL, Cohen-Adad J. 8-channel Tx dipole and 20-channel Rx loop coil array for MRI of the cervical spinal cord at 7 Tesla. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.08.527664. [PMID: 36798276 PMCID: PMC9934596 DOI: 10.1101/2023.02.08.527664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The quality of cervical spinal cord images can be improved by the use of tailored radiofrequency coil solutions for ultra-high field imaging; however, very few commercial and research 7 Tesla radiofrequency coils currently exist for the spinal cord, and in particular those with parallel transmit capabilities. This work presents the design, testing and validation of a pTx/Rx coil for the human neck and cervical/upper-thoracic spinal cord. The pTx portion is composed of 8 dipoles to ensure high homogeneity over this large region of the spinal cord. The Rx portion is made of 20 semi-adaptable overlapping loops to produce high Signal-to-noise ratio (SNR) across the patient population. The coil housing is designed to facilitate patient positioning and comfort, while being tight fitting to ensure high sensitivity. We demonstrate RF shimming capabilities to optimize B 1 + uniformity, power efficiency and/or specific absorption rate (SAR) efficiency. B 1 + homogeneity, SNR and g-factor was evaluated in adult volunteers and demonstrated excellent performance from the occipital lobe down to the T4-T5 level. We compared the proposed coil with two state-of-the-art head and head/neck coils, confirming its superiority in the cervical and upper-thoracic regions of the spinal cord. This coil solution therefore provides a convincing platform for producing the high image quality necessary for clinical and research scanning of the upper spinal cord.
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Affiliation(s)
- Nibardo Lopez Rios
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC, Canada
| | - Kyle M. Gilbert
- Centre for Functional and Metabolic Mapping, The University of Western Ontario, London, ON, Canada
| | - Daniel Papp
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC, Canada
| | - Gaspard Cereza
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC, Canada
| | - Alexandru Foias
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC, Canada
| | - D. Rangaprakash
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Markus W. May
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany
- High Field and Hybrid MR Imaging, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Bastien Guerin
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Lawrence L. Wald
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Boris Keil
- Institute of Medical Physics and Radiation Protection, University of Applied Sciences Mittelhessen, Giessen, Germany
- Department of Diagnostic and Interventional Radiology, University Hospital Marburg, Philipps University of Marburg, Marburg, Germany
| | - Jason P. Stockmann
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Robert L. Barry
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
- Harvard Medical School, Boston, MA, USA
- Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC, Canada
- Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
- Mila – Quebec AI Institute, Montreal, QC, Canada
- Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, QC, Canada
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8
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Williams SN, McElhinney P, Gunamony S. Ultra-high field MRI: parallel-transmit arrays and RF pulse design. Phys Med Biol 2023; 68. [PMID: 36410046 DOI: 10.1088/1361-6560/aca4b7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 11/21/2022] [Indexed: 11/22/2022]
Abstract
This paper reviews the field of multiple or parallel radiofrequency (RF) transmission for magnetic resonance imaging (MRI). Currently the use of ultra-high field (UHF) MRI at 7 tesla and above is gaining popularity, yet faces challenges with non-uniformity of the RF field and higher RF power deposition. Since its introduction in the early 2000s, parallel transmission (pTx) has been recognized as a powerful tool for accelerating spatially selective RF pulses and combating the challenges associated with RF inhomogeneity at UHF. We provide a survey of the types of dedicated RF coils used commonly for pTx and the important modeling of the coil behavior by electromagnetic (EM) field simulations. We also discuss the additional safety considerations involved with pTx such as the specific absorption rate (SAR) and how to manage them. We then describe the application of pTx with RF pulse design, including a practical guide to popular methods. Finally, we conclude with a description of the current and future prospects for pTx, particularly its potential for routine clinical use.
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Affiliation(s)
- Sydney N Williams
- Imaging Centre of Excellence, University of Glasgow, Glasgow, United Kingdom
| | - Paul McElhinney
- Imaging Centre of Excellence, University of Glasgow, Glasgow, United Kingdom
| | - Shajan Gunamony
- Imaging Centre of Excellence, University of Glasgow, Glasgow, United Kingdom.,MR CoilTech Limited, Glasgow, United Kingdom
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9
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Trò R, Roascio M, Tortora D, Severino M, Rossi A, Cohen-Adad J, Fato MM, Arnulfo G. Diffusion Kurtosis Imaging of Neonatal Spinal Cord in Clinical Routine. FRONTIERS IN RADIOLOGY 2022; 2:794981. [PMID: 37492682 PMCID: PMC10365122 DOI: 10.3389/fradi.2022.794981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/20/2022] [Indexed: 07/27/2023]
Abstract
Diffusion kurtosis imaging (DKI) has undisputed advantages over the more classical diffusion magnetic resonance imaging (dMRI) as witnessed by the fast-increasing number of clinical applications and software packages widely adopted in brain imaging. However, in the neonatal setting, DKI is still largely underutilized, in particular in spinal cord (SC) imaging, because of its inherently demanding technological requirements. Due to its extreme sensitivity to non-Gaussian diffusion, DKI proves particularly suitable for detecting complex, subtle, fast microstructural changes occurring in this area at this early and critical stage of development, which are not identifiable with only DTI. Given the multiplicity of congenital anomalies of the spinal canal, their crucial effect on later developmental outcome, and the close interconnection between the SC region and the brain above, managing to apply such a method to the neonatal cohort becomes of utmost importance. This study will (i) mention current methodological challenges associated with the application of advanced dMRI methods, like DKI, in early infancy, (ii) illustrate the first semi-automated pipeline built on Spinal Cord Toolbox for handling the DKI data of neonatal SC, from acquisition setting to estimation of diffusion measures, through accurate adjustment of processing algorithms customized for adult SC, and (iii) present results of its application in a pilot clinical case study. With the proposed pipeline, we preliminarily show that DKI is more sensitive than DTI-related measures to alterations caused by brain white matter injuries in the underlying cervical SC.
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Affiliation(s)
- Rosella Trò
- Departments of Informatics, Bioengineering, Robotics, and System Engineering, University of Genoa, Genoa, Italy
| | - Monica Roascio
- Departments of Informatics, Bioengineering, Robotics, and System Engineering, University of Genoa, Genoa, Italy
| | | | | | - Andrea Rossi
- Neuroradiology Unit, Istituto Giannina Gaslini, Genoa, Italy
- Department of Health Sciences, University of Genoa, Genoa, Italy
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
- Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
- Mila—Quebec AI Institute, Montreal, QC, Canada
| | - Marco Massimo Fato
- Departments of Informatics, Bioengineering, Robotics, and System Engineering, University of Genoa, Genoa, Italy
| | - Gabriele Arnulfo
- Departments of Informatics, Bioengineering, Robotics, and System Engineering, University of Genoa, Genoa, Italy
- Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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10
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Diagnosis of Lumbar Spondylolisthesis Using Optimized Pretrained CNN Models. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2022; 2022:7459260. [PMID: 35432510 PMCID: PMC9007141 DOI: 10.1155/2022/7459260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 02/12/2022] [Accepted: 02/18/2022] [Indexed: 02/05/2023]
Abstract
Spondylolisthesis refers to the slippage of one vertebral body over the adjacent one. It is a chronic condition that requires early detection to prevent unpleasant surgery. The paper presents an optimized deep learning model for detecting spondylolisthesis in X-ray radiographs. The dataset contains a total of 299 X-ray radiographs from which 156 images are showing the spine with spondylolisthesis and 143 images are of the normal spine. Image augmentation technique is used to increase the data samples. In this study, VGG16 and InceptionV3 models were used for the image classification task. The developed model is optimized by utilizing the TFLite model optimization technique. The experimental result shows that the VGG16 model has achieved a 98% accuracy rate, which is higher than InceptionV3's 96% accuracy rate. The size of the implemented model is reduced up to four times so it can be used on small devices. The compressed VGG16 and InceptionV3 models have achieved 100% and 96% accuracy rate, respectively. Our finding shows that the implemented models were outperformed in the diagnosis of lumbar spondylolisthesis as compared to the model suggested by Varcin et al. (which had a maximum of 93% accuracy rate). Also, the developed quantized model has achieved higher accuracy rate than Zebin and Rezvy's (VGG16 + TFLite) model with 90% accuracy. Furthermore, by evaluating the model's performance on other publicly available datasets, we have generalised our approach on the public platform.
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11
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Le Ster C, Mauconduit F, Massire A, Boulant N, Gras V. Standardized universal pulse: A fast RF calibration approach to improve flip angle accuracy in parallel transmission. Magn Reson Med 2022; 87:2839-2850. [PMID: 35122302 DOI: 10.1002/mrm.29180] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE In parallel transmission (pTX), subject-tailored RF pulses allow achieving excellent flip angle (FA) accuracy but often require computationally extensive online optimizations, precise characterization of the static field ( Δ B 0 ), and the transmit RF field ( B 1 + ) distributions. This costs time and requires expertise from the MR user. Universal pulses (UPs) have been proposed to reduce this burden, yet, with a penalty in FA accuracy. This study introduces the concept of standardized universal pulses (SUPs), where pulses are designed offline and adjusted to the subject through a fast online calibration scan. METHODS A SUP is designed offline using a so-called standardized database, wherein each B 1 + map has been normalized to a reference transmit RF field distribution. When scanning a new subject, a 3-slice B 1 + acquisition (scan time < 10 s) is performed and used to adjust the SUP to the subject through a linear transform. SUP performance was assessed at 7T with simulations by computing the FA-normalized root mean square error (FA-NRMSE) and the FA pattern stability as measured by the average and coefficient of variation of the FA across 15 control subjects, along with in vivo experiments using an MP2RAGE sequence implementing the SUP variant for the FLASH readout. RESULTS Adjusted SUP improved the FA-NRMSE (8.8 % for UP vs. 7.1 % for adjusted SUP). Experimentally in vivo, this translated in an improved signal homogeneity and more accurate T 1 quantification using MP2RAGE. CONCLUSION The proposed SUP approach improves excitation accuracy (FA-NRMSE) while preserving the same offline pulse design principle as offered by UPs.
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Affiliation(s)
- Caroline Le Ster
- NeuroSpin, CEA, CNRS, BAOBAB, Université Paris-Saclay, Gif-Sur-Yvette, France
| | - Franck Mauconduit
- NeuroSpin, CEA, CNRS, BAOBAB, Université Paris-Saclay, Gif-Sur-Yvette, France
| | | | - Nicolas Boulant
- NeuroSpin, CEA, CNRS, BAOBAB, Université Paris-Saclay, Gif-Sur-Yvette, France
| | - Vincent Gras
- NeuroSpin, CEA, CNRS, BAOBAB, Université Paris-Saclay, Gif-Sur-Yvette, France
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12
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Forodighasemabadi A, Baucher G, Soustelle L, Troalen T, Girard OM, Guye M, Grisoli JB, Ranjeva JP, Duhamel G, Callot V. Spinal cord and brain tissue impairments as long-term effects of rugby practice? An exploratory study based on T1 and ihMTsat measures. NEUROIMAGE: CLINICAL 2022; 35:103124. [PMID: 35905667 PMCID: PMC9421542 DOI: 10.1016/j.nicl.2022.103124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/14/2022] [Accepted: 07/20/2022] [Indexed: 12/03/2022] Open
Abstract
Diffuse degeneration of spinal cord (higher T1) is observed in retired rugby players. Demyelination of brain WM tracts (higher T1 / lower ihMTsat values) is present in rugby players. Early aging in both brain and spinal cord tissues may be linked to the rugby practice. The aforementioned effects may suggest cumulative effects of long-term impacts on the tissues.
Rugby players are subject to multiple impacts to their head and neck that could have adverse neurological effects and put them at increased risk of neurodegeneration. Previous studies demonstrated altered default mode network and diffusion metrics on brain, as well as more foraminal stenosis, disc protrusion and neck pain among players of contact sports as compared to healthy controls. However, the long-term effects of practice and repetitive impacts on brain and cervical spinal cord (cSC) of the rugby players have never been systematically investigated. In this study, 15 retired professional and amateur rugby players (R) and 15 age-matched healthy controls (HC) (all males; mean age R: 46.8 ± 7.6; and HC: 48.6 ± 9.5) were recruited both to investigate cord impairments and further characterize brain structure damage. Medical questionnaires including modified Japanese Orthopedic Association scale (mJOA) and Neck Disability Index (NDI) were filled by all participants. A 3 T multi-parametric MR protocol including conventional qualitative techniques such as T1-, T2-, and T2*-weighted sequences, as well as state-of-the art quantitative techniques including MP2RAGE T1 mapping and 3D ihMTRAGE, was used on both brain and cSC. Normalized brain WM and GM volumes, spine Overall Stenosis Score, cord cross-sectional area and regional T1 and ihMT metrics were derived from these acquisitions. Rugby players showed significantly higher NDI scores, as well as a faster decline of normalized brain GM volume with age as compared to HC. Moreover, higher T1 values on cSC suggestive of structural degeneration, together with higher T1 and lower ihMTsat on brain WM suggestive of demyelination, were observed in retired rugby players as compared to age-matched controls, which may suggest cumulative effects of long-term impacts on the tissues. Metrics also suggest early aging and different aging processes on brain tissue in the players. These preliminary observations provide new insights in the domain, which should now be further investigated on larger cohorts and multicentric longitudinal studies, and further correlated to the likelihood of neurodegenerative diseases and risk factors.
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13
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Brun G, Testud B, Girard OM, Lehmann P, de Rochefort L, Besson P, Massire A, Ridley B, Girard N, Guye M, Ranjeva JP, Le Troter A. Automatic segmentation of Deep Grey Nuclei using a high-resolution 7T MRI Atlas - quantification of T1 values in healthy volunteers. Eur J Neurosci 2021; 55:438-460. [PMID: 34939245 DOI: 10.1111/ejn.15575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 11/30/2022]
Abstract
We present a new consensus atlas of deep grey nuclei obtained by shape-based averaging of manual segmentation of two experienced neuroradiologists and optimized from 7T MP2RAGE images acquired at (0.6mm)3 in 60 healthy subjects. A group-wise normalization method was used to build a high-contrast and high-resolution T1 -weighted brain template (0.5mm)3 using data from 30 out of the 60 controls. Delineation of 24 deep grey nuclei per hemisphere, including the claustrum and twelve thalamic nuclei, was then performed by two expert neuroradiologists and reviewed by a third neuroradiologist according to tissue contrast and external references based on the Morel atlas. Corresponding deep grey matter structures were also extracted from the Morel and CIT168 atlases. The data-derived, Morel and CIT168 atlases were all applied at the individual level using non-linear registration to fit the subject reference and to extract absolute mean quantitative T1 values derived from the 3D-MP2RAGE volumes, after correction for residual B1 + biases. Three metrics (The Dice and the volumetric similarity coefficients, and a novel Hausdorff distance) were used to estimate the inter-rater agreement of manual MRI segmentation and inter-atlas variability, and these metrics were measured to quantify biases due to image registration and their impact on the measurements of the quantitative T1 values was highlighted. This represents a fully-automated segmentation process permitting the extraction of unbiased normative T1 values in a population of young healthy controls as a reference for characterizing subtle structural alterations of deep grey nuclei relevant to a range of neurological diseases.
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Affiliation(s)
- Gilles Brun
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, Service de Neuroradiologie, Marseille, France
| | - Benoit Testud
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, Service de Neuroradiologie, Marseille, France
| | - Olivier M Girard
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Pierre Lehmann
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, Service de Neuroradiologie, Marseille, France
| | - Ludovic de Rochefort
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Pierre Besson
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Aurélien Massire
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Ben Ridley
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France.,IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italia
| | - Nadine Girard
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, Service de Neuroradiologie, Marseille, France
| | - Maxime Guye
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Jean-Philippe Ranjeva
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
| | - Arnaud Le Troter
- Aix Marseille Univ, CNRS, CRMBM, Marseille, France.,AP-HM, CHU Timone, Pôle d'Imagerie Médicale, CEMEREM, Marseille, France
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14
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Kreiter DJ, van den Hurk J, Wiggins CJ, Hupperts RMM, Gerlach OHH. Ultra-high field spinal cord MRI in multiple sclerosis: Where are we standing? A literature review. Mult Scler Relat Disord 2021; 57:103436. [PMID: 34871855 DOI: 10.1016/j.msard.2021.103436] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/18/2021] [Accepted: 11/27/2021] [Indexed: 12/24/2022]
Abstract
Magnetic resonance imaging (MRI) is a cornerstone in multiple sclerosis (MS) diagnostics and monitoring. Ultra-high field (UHF) MRI is being increasingly used and becoming more accessible. Due to the small diameter and mobility of the spinal cord, imaging this structure at ultra-high fields poses additional challenges compared to brain imaging. Here we review the potential benefits for the MS field by providing a literature overview of the use UHF spinal cord MRI in MS research and we elaborate on the challenges that are faced. Benefits include increased signal- and contrast-to-noise, enabling for higher spatial resolutions, which can improve MS lesion sensitivity in both the spinal white matter as well as grey matter. Additionally, these benefits can aid imaging of microstructural abnormalities in the spinal cord in MS using advanced MRI techniques like functional imaging, MR spectroscopy and diffusion-based techniques. Technical challenges include increased magnetic field inhomogeneities, distortions from physiological motion and optimalisation of sequences. Approaches including parallel imaging techniques, real time shimming and retrospective compensation of physiological motion are making it increasingly possible to unravel the potential of spinal cord UHF MRI in the context of MS research.
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Affiliation(s)
- Daniël J Kreiter
- Academic MS center Zuyderland, Department of Neurology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands; School for Mental Health and Neuroscience, Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands.
| | - Job van den Hurk
- Scannexus, Maastricht, The Netherlands; Maastricht University, Faculty of Health, Medicine & Life Sciences, Maastricht, The Netherlands
| | | | - Raymond M M Hupperts
- Academic MS center Zuyderland, Department of Neurology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands; School for Mental Health and Neuroscience, Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Oliver H H Gerlach
- Academic MS center Zuyderland, Department of Neurology, Zuyderland Medical Center, Sittard-Geleen, The Netherlands; School for Mental Health and Neuroscience, Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands.
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15
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Platt T, Ladd ME, Paech D. 7 Tesla and Beyond: Advanced Methods and Clinical Applications in Magnetic Resonance Imaging. Invest Radiol 2021; 56:705-725. [PMID: 34510098 PMCID: PMC8505159 DOI: 10.1097/rli.0000000000000820] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/07/2021] [Accepted: 08/07/2021] [Indexed: 12/15/2022]
Abstract
ABSTRACT Ultrahigh magnetic fields offer significantly higher signal-to-noise ratio, and several magnetic resonance applications additionally benefit from a higher contrast-to-noise ratio, with static magnetic field strengths of B0 ≥ 7 T currently being referred to as ultrahigh fields (UHFs). The advantages of UHF can be used to resolve structures more precisely or to visualize physiological/pathophysiological effects that would be difficult or even impossible to detect at lower field strengths. However, with these advantages also come challenges, such as inhomogeneities applying standard radiofrequency excitation techniques, higher energy deposition in the human body, and enhanced B0 field inhomogeneities. The advantages but also the challenges of UHF as well as promising advanced methodological developments and clinical applications that particularly benefit from UHF are discussed in this review article.
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Affiliation(s)
- Tanja Platt
- From the Medical Physics in Radiology, German Cancer Research Center (DKFZ)
| | - Mark E. Ladd
- From the Medical Physics in Radiology, German Cancer Research Center (DKFZ)
- Faculty of Physics and Astronomy
- Faculty of Medicine, University of Heidelberg, Heidelberg
- Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen
| | - Daniel Paech
- Division of Radiology, German Cancer Research Center (DKFZ), Heidelberg
- Clinic for Neuroradiology, University of Bonn, Bonn, Germany
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16
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Generic acquisition protocol for quantitative MRI of the spinal cord. Nat Protoc 2021; 16:4611-4632. [PMID: 34400839 PMCID: PMC8811488 DOI: 10.1038/s41596-021-00588-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 06/10/2021] [Indexed: 02/08/2023]
Abstract
Quantitative spinal cord (SC) magnetic resonance imaging (MRI) presents many challenges, including a lack of standardized imaging protocols. Here we present a prospectively harmonized quantitative MRI protocol, which we refer to as the spine generic protocol, for users of 3T MRI systems from the three main manufacturers: GE, Philips and Siemens. The protocol provides guidance for assessing SC macrostructural and microstructural integrity: T1-weighted and T2-weighted imaging for SC cross-sectional area computation, multi-echo gradient echo for gray matter cross-sectional area, and magnetization transfer and diffusion weighted imaging for assessing white matter microstructure. In a companion paper from the same authors, the spine generic protocol was used to acquire data across 42 centers in 260 healthy subjects. The key details of the spine generic protocol are also available in an open-access document that can be found at https://github.com/spine-generic/protocols . The protocol will serve as a starting point for researchers and clinicians implementing new SC imaging initiatives so that, in the future, inclusion of the SC in neuroimaging protocols will be more common. The protocol could be implemented by any trained MR technician or by a researcher/clinician familiar with MRI acquisition.
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17
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Forodighasemabadi A, Rasoanandrianina H, El Mendili MM, Guye M, Callot V. An optimized MP2RAGE sequence for studying both brain and cervical spinal cord in a single acquisition at 3T. Magn Reson Imaging 2021; 84:18-26. [PMID: 34517015 DOI: 10.1016/j.mri.2021.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 11/30/2022]
Abstract
Magnetization Prepared 2 Rapid Acquisition Gradient Echo (MP2RAGE) is a T1 mapping technique that has been used broadly on brain and recently on cervical spinal cord (cSC). The growing interest for combined investigation of brain and SC in numerous pathologies of the central nervous system such as multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and traumatic injuries, now brings about the need for optimization with regards to this specific investigation. This implies large spatial coverage with high spatial resolution and short acquisition time, high CNR and low B1+ sensitivity, as well as high reproducibility and robust post-processing tools for T1 quantification in different regions of brain and SC. In this work, a dedicated protocol (referred to as Pr-BSC) has been optimized for simultaneous brain and cSC T1 MP2RAGE acquisition at 3T. After computer simulation optimization, the protocol was applied for in vivo validation experiments and compared to previously published state of the art protocols focusing on either the brain (Pr-B) or the cSC (Pr-SC). Reproducibility and in-ROI standard deviations were assessed on healthy volunteers in the perspective of future clinical use. The mean T1 values, obtained by the Pr-BSC, in brain white, gray and deep gray matters were: (mean ± in-ROI SD) 792 ± 27 ms, 1339 ± 139 ms and 1136 ± 88 ms, respectively. In cSC, T1 values for white matter corticospinal, posterior sensory, lateral sensory and rubro/reticulospinal tracts were 902 ± 41 ms, 920 ± 35 ms, 903 ± 46 ms, 891 ± 41 ms, respectively, and 954 ± 32 ms for anterior and intermediate gray matter. The Pr-BSC protocol showed excellent agreement with previously proposed Pr-B on brain and Pr-SC on cSC, with very high inter-scan reproducibility (coefficients of variation of 0.52 ± 0.36% and 1.12 ± 0.62% on brain and cSC, respectively). This optimized protocol covering both brain and cSC with a sub-millimetric isotropic spatial resolution in one acquisition of less than 8 min, opens up great perspectives for clinical applications focusing on degenerative tissue such as encountered in MS and ALS.
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Affiliation(s)
- Arash Forodighasemabadi
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France; Aix-Marseille Univ, Université Gustave Eiffel, LBA, Marseille, France; iLab-Spine International Associated Laboratory, Marseille-Montreal, France, Canada
| | - Henitsoa Rasoanandrianina
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France; Aix-Marseille Univ, Université Gustave Eiffel, LBA, Marseille, France; iLab-Spine International Associated Laboratory, Marseille-Montreal, France, Canada
| | - Mohamed Mounir El Mendili
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France
| | - Maxime Guye
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France
| | - Virginie Callot
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France; APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France; iLab-Spine International Associated Laboratory, Marseille-Montreal, France, Canada.
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18
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Structural and resting state functional connectivity beyond the cortex. Neuroimage 2021; 240:118379. [PMID: 34252527 DOI: 10.1016/j.neuroimage.2021.118379] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/21/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022] Open
Abstract
Mapping the structural and functional connectivity of the central nervous system has become a key area within neuroimaging research. While detailed network structures across the entire brain have been probed using animal models, non-invasive neuroimaging in humans has thus far been dominated by cortical investigations. Beyond the cortex, subcortical nuclei have traditionally been less accessible due to their smaller size and greater distance from radio frequency coils. However, major neuroimaging developments now provide improved signal and the resolution required to study these structures. Here, we present an overview of the connectivity between the amygdala, brainstem, cerebellum, spinal cord and the rest of the brain. While limitations to their imaging and analyses remain, we also provide some recommendations and considerations for mapping brain connectivity beyond the cortex.
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19
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Massire A, Seiler C, Troalen T, Girard OM, Lehmann P, Brun G, Bartoli A, Audoin B, Bartolomei F, Pelletier J, Callot V, Kober T, Ranjeva JP, Guye M. T1-Based Synthetic Magnetic Resonance Contrasts Improve Multiple Sclerosis and Focal Epilepsy Imaging at 7 T. Invest Radiol 2021; 56:127-133. [PMID: 32852445 DOI: 10.1097/rli.0000000000000718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Ultra-high field magnetic resonance imaging (MRI) (≥7 T) is a unique opportunity to improve the clinical diagnosis of brain pathologies, such as multiple sclerosis or focal epilepsy. However, several shortcomings of 7 T MRI, such as radiofrequency field inhomogeneities, could degrade image quality and hinder radiological interpretation. To address these challenges, an original synthetic MRI method based on T1 mapping achieved with the magnetization-prepared 2 rapid acquisition gradient echo (MP2RAGE) sequence was developed. The radiological quality of on-demand T1-based contrasts generated by this technique was evaluated in multiple sclerosis and focal epilepsy imaging at 7 T. MATERIALS AND METHODS This retrospective study was carried out from October 2017 to September 2019 and included 21 patients with different phenotypes of multiple sclerosis and 35 patients with focal epilepsy who underwent MRI brain examinations using a whole-body investigative 7 T magnetic resonance system. The quality of 2 proposed synthetic contrast images were assessed and compared with conventional images acquired at 7 T using the MP2RAGE sequence by 4 radiologists, evaluating 3 qualitative criteria: signal homogeneity, contrast intensity, and lesion visualization. Statistical analyses were performed on reported quality scores using Wilcoxon rank tests and further multiple comparisons tests. Intraobserver and interobserver reliabilities were calculated as well. RESULTS Radiological quality scores were reported higher for synthetic images when compared with original images, regardless of contrast, pathologies, or raters considered, with significant differences found for all 3 criteria (P < 0.0001, Wilcoxon rank test). None of the 4 radiologists ever rated a synthetic image "markedly worse" than an original image. Synthetic images were rated slightly less satisfying for only 3 epileptic patients, without precluding lesion identification. CONCLUSION T1-based synthetic MRI with the MP2RAGE sequence provided on-demand contrasts and high-quality images to the radiologist, facilitating lesion visualization in multiple sclerosis and focal epilepsy, while reducing the magnetic resonance examination total duration by removing an additional sequence.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Fabrice Bartolomei
- Pôle de Neurosciences Cliniques, Service de Neurophysiologie, APHM, Hôpital de la Timone, Marseille, France
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20
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Imaging of the Spinal Cord in Multiple Sclerosis: Past, Present, Future. Brain Sci 2020; 10:brainsci10110857. [PMID: 33202821 PMCID: PMC7696997 DOI: 10.3390/brainsci10110857] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 10/30/2020] [Accepted: 11/11/2020] [Indexed: 11/17/2022] Open
Abstract
Spinal cord imaging in multiple sclerosis (MS) plays a significant role in diagnosing and tracking disease progression. The spinal cord is one of four key areas of the central nervous system where documenting the dissemination in space in the McDonald criteria for diagnosing MS. Spinal cord lesion load and the severity of cord atrophy are believed to be more relevant to disability than white matter lesions in the brain in different phenotypes of MS. Axonal loss contributes to spinal cord atrophy in MS and its degree correlates with disease severity and prognosis. Therefore, measures of axonal loss are often reliable biomarkers for monitoring disease progression. With recent technical advances, more and more qualitative and quantitative MRI techniques have been investigated in an attempt to provide objective and reliable diagnostic and monitoring biomarkers in MS. In this article, we discuss the role of spinal cord imaging in the diagnosis and prognosis of MS and, additionally, we review various techniques that may improve our understanding of the disease.
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21
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Rasoanandrianina H, Demortière S, Trabelsi A, Ranjeva JP, Girard O, Duhamel G, Guye M, Pelletier J, Audoin B, Callot V. Sensitivity of the Inhomogeneous Magnetization Transfer Imaging Technique to Spinal Cord Damage in Multiple Sclerosis. AJNR Am J Neuroradiol 2020; 41:929-937. [PMID: 32414903 DOI: 10.3174/ajnr.a6554] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 03/12/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND PURPOSE The inhomogeneous magnetization transfer technique has demonstrated high specificity for myelin, and has shown sensitivity to multiple sclerosis-related impairment in brain tissue. Our aim was to investigate its sensitivity to spinal cord impairment in MS relative to more established MR imaging techniques (volumetry, magnetization transfer, DTI). MATERIALS AND METHODS Anatomic images covering the cervical spinal cord from the C1 to C6 levels and DTI, magnetization transfer/inhomogeneous magnetization transfer images at the C2/C5 levels were acquired in 19 patients with MS and 19 paired healthy controls. Anatomic images were segmented in spinal cord GM and WM, both manually and using the AMU40 atlases. MS lesions were manually delineated. MR metrics were analyzed within normal-appearing and lesion regions in anterolateral and posterolateral WM and compared using Wilcoxon rank tests and z scores. Correlations between MR metrics and clinical scores in patients with MS were evaluated using the Spearman rank correlation. RESULTS AMU40-based C1-to-C6 GM/WM automatic segmentations in patients with MS were evaluated relative to manual delineation. Mean Dice coefficients were 0.75/0.89, respectively. All MR metrics (WM/GM cross-sectional areas, normal-appearing and lesion diffusivities, and magnetization transfer/inhomogeneous magnetization transfer ratios) were observed altered in patients compared with controls (P < .05). Additionally, the absolute inhomogeneous magnetization transfer ratio z scores were significantly higher than those of the other MR metrics (P < .0001), suggesting a higher inhomogeneous magnetization transfer sensitivity toward spinal cord impairment in MS. Significant correlations with the Expanded Disability Status Scale (ρ = -0.73/P = .02, ρ = -0.81/P = .004) and the total Medical Research Council scale (ρ = 0.80/P = .009, ρ = -0.74/P = .02) were observed for inhomogeneous magnetization transfer and magnetization transfer ratio z scores, respectively, in normal-appearing WM regions, while weaker and nonsignificant correlations were obtained for DTI metrics. CONCLUSIONS With inhomogeneous magnetization transfer being highly sensitive to spinal cord damage in MS compared with conventional magnetization transfer and DTI, it could generate great clinical interest for longitudinal follow-up and potential remyelinating clinical trials. In line with other advanced myelin techniques with which it could be compared, it opens perspectives for multicentric investigations.
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Affiliation(s)
- H Rasoanandrianina
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Laboratoire de Biomécanique Appliquée, Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Reseaux, Aix-Marseille Université; iLab-Spine International Associated Laboratory (H.R., J.P.R., V.C.), Marseille-Montreal, France-Canada
| | - S Demortière
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Department of Neurology (S.D., J.P., B.A.), Centre Hospitalier Universitaire Timone, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - A Trabelsi
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - J P Ranjeva
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Laboratoire de Biomécanique Appliquée, Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Reseaux, Aix-Marseille Université; iLab-Spine International Associated Laboratory (H.R., J.P.R., V.C.), Marseille-Montreal, France-Canada
| | - O Girard
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - G Duhamel
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - M Guye
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France
| | - J Pelletier
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Department of Neurology (S.D., J.P., B.A.), Centre Hospitalier Universitaire Timone, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - B Audoin
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France.,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Department of Neurology (S.D., J.P., B.A.), Centre Hospitalier Universitaire Timone, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - V Callot
- From the Center for Magnetic Resonance in Biology and Medicine (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Centre National de la Recherche Scientifique, Aix-Marseille Université, Marseille, France .,Centre d'Exploration Métabolique par Résonance Magnétique (H.R., S.D., A.T., J.P.R., O.G., G.D., M.G., J.P., B.A., V.C.), Assistance Publique-Hopitaux de Marseille, Hôpital Universitaire Timone, Marseille, France.,Laboratoire de Biomécanique Appliquée, Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Reseaux, Aix-Marseille Université; iLab-Spine International Associated Laboratory (H.R., J.P.R., V.C.), Marseille-Montreal, France-Canada
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22
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Lévy S, Roche PH, Guye M, Callot V. Feasibility of human spinal cord perfusion mapping using dynamic susceptibility contrast imaging at 7T: Preliminary results and identified guidelines. Magn Reson Med 2020; 85:1183-1194. [PMID: 33151009 DOI: 10.1002/mrm.28559] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE To explore the feasibility of dynamic susceptibility contrast MRI at 7 Tesla for human spinal cord perfusion mapping and fill the gap between brain and spinal cord perfusion mapping techniques. METHODS Acquisition protocols for high-resolution single shot EPI in the spinal cord were optimized for both spin-echo and gradient-echo preparations, including cardiac gating, acquisition times and breathing cycle recording. Breathing-induced MRI signal fluctuations were investigated in healthy volunteers. A specific image- and signal-processing pipeline was implemented to address them. Dynamic susceptibility contrast was then evaluated in 3 healthy volunteers and 5 patients. Bolus depiction on slice-wise signal within cord was investigated, and maps of relative perfusion indices were computed. RESULTS Signal fluctuations were increased by 1.9 and 2.3 in free-breathing compared to apnea with spin-echo and gradient-echo, respectively. The ratio between signal fluctuations and bolus peak in healthy volunteers was 5.0% for spin-echo and 3.8% for gradient-echo, allowing clear depiction of the bolus on every slice and yielding relative blood flow and volume maps exhibiting the expected higher perfusion of gray matter. However, signal fluctuations in patients were increased by 4 in average (using spin-echo), compromising the depiction of the bolus in slice-wise signal. Moreover, 3 of 18 slices had to be discarded because of fat-aliasing artifacts. CONCLUSION Dynamic susceptibility contrast MRI at 7 Tesla showed great potential for spinal cord perfusion mapping with a reliability never achieved thus far for single subject and single slice measurements. Signal stability needs to be improved in acquisition conditions associated with patients; guidelines to achieve that have been identified and shared.
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Affiliation(s)
- Simon Lévy
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France.,APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France.,Aix-Marseille Univ, Univ Gustave Eiffel, LBA, Marseille, France.,iLab-Spine International Associated Laboratory, Marseille-Montreal, France-Canada
| | - Pierre-Hugues Roche
- iLab-Spine International Associated Laboratory, Marseille-Montreal, France-Canada.,Neurosurgery Department, APHM, Hopital Nord, Marseille, France
| | - Maxime Guye
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France.,APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France
| | - Virginie Callot
- Aix-Marseille Univ, CNRS, CRMBM, Marseille, France.,APHM, Hopital Universitaire Timone, CEMEREM, Marseille, France.,iLab-Spine International Associated Laboratory, Marseille-Montreal, France-Canada
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23
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Grussu F, Battiston M, Veraart J, Schneider T, Cohen-Adad J, Shepherd TM, Alexander DC, Fieremans E, Novikov DS, Gandini Wheeler-Kingshott CAM. Multi-parametric quantitative in vivo spinal cord MRI with unified signal readout and image denoising. Neuroimage 2020; 217:116884. [PMID: 32360689 PMCID: PMC7378937 DOI: 10.1016/j.neuroimage.2020.116884] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 03/18/2020] [Accepted: 04/23/2020] [Indexed: 12/11/2022] Open
Abstract
Multi-parametric quantitative MRI (qMRI) of the spinal cord is a promising non-invasive tool to probe early microstructural damage in neurological disorders. It is usually performed in vivo by combining acquisitions with multiple signal readouts, which exhibit different thermal noise levels, geometrical distortions and susceptibility to physiological noise. This ultimately hinders joint multi-contrast modelling and makes the geometric correspondence of parametric maps challenging. We propose an approach to overcome these limitations, by implementing state-of-the-art microstructural MRI of the spinal cord with a unified signal readout in vivo (i.e. with matched spatial encoding parameters across a range of imaging contrasts). We base our acquisition on single-shot echo planar imaging with reduced field-of-view, and obtain data from two different vendors (vendor 1: Philips Achieva; vendor 2: Siemens Prisma). Importantly, the unified acquisition allows us to compare signal and noise across contrasts, thus enabling overall quality enhancement via multi-contrast image denoising methods. As a proof-of-concept, here we provide a demonstration with one such method, known as Marchenko-Pastur (MP) Principal Component Analysis (PCA) denoising. MP-PCA is a singular value (SV) decomposition truncation approach that relies on redundant acquisitions, i.e. such that the number of measurements is large compared to the number of components that are maintained in the truncated SV decomposition. Here we used in vivo and synthetic data to test whether a unified readout enables more efficient MP-PCA denoising of less redundant acquisitions, since these can be denoised jointly with more redundant ones. We demonstrate that a unified readout provides robust multi-parametric maps, including diffusion and kurtosis tensors from diffusion MRI, myelin metrics from two-pool magnetisation transfer, and T1 and T2 from relaxometry. Moreover, we show that MP-PCA improves the quality of our multi-contrast acquisitions, since it reduces the coefficient of variation (i.e. variability) by up to 17% for mean kurtosis, 8% for bound pool fraction (myelin-sensitive), and 13% for T1, while enabling more efficient denoising of modalities limited in redundancy (e.g. relaxometry). In conclusion, multi-parametric spinal cord qMRI with unified readout is feasible and provides robust microstructural metrics with matched resolution and distortions, whose quality benefits from multi-contrast denoising methods such as MP-PCA.
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Affiliation(s)
- Francesco Grussu
- Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK; Centre for Medical Image Computing, Department of Computer Science, University College London, London, UK.
| | - Marco Battiston
- Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
| | - Jelle Veraart
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, USA
| | | | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, Canada
| | - Timothy M Shepherd
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, USA
| | - Daniel C Alexander
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, UK
| | - Els Fieremans
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, USA
| | - Dmitry S Novikov
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, USA
| | - Claudia A M Gandini Wheeler-Kingshott
- Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK; Brain MRI 3T Research Centre, IRCCS Mondino Foundation, Pavia, Italy; Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy
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24
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Geldschläger O, Bosch D, Avdievich NI, Henning A. Ultrahigh-resolution quantitative spinal cord MRI at 9.4T. Magn Reson Med 2020; 85:1013-1027. [PMID: 32789980 DOI: 10.1002/mrm.28455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 07/06/2020] [Accepted: 07/10/2020] [Indexed: 11/08/2022]
Abstract
PURPOSE To present the results of the first human spinal cord in vivo MRI scans at 9.4T. METHODS A human brain coil was used to image the human spinal cord at 9.4T. All anatomical images were acquired with a T2 *-weighted gradient-echo sequence. A comparison of the influence of four different B0 shimming routines on the image quality was performed. Intrinsic signal-to-noise-ratio maps were determined using a pseudo-multiple replica approach. Measurements with different echo times were compared and processed to one multiecho data image combination image. Based on the multiecho acquisitions, T2 *-relaxation time maps were calculated. Algorithmic spinal cord detection and gray matter/white matter segmentation were tested. RESULTS An echo time between 9 and 13.8 ms compromised best between gray matter/white matter contrast and image quality. A maximum in-plane resolution of 0.15 × 0.15 mm2 was achieved for anatomical images. These images offered excellent image quality and made small structures of the spinal cord visible. The scanner vendor implemented B0 shimming routine performed best during this work. Intrinsic signal-to-noise-ratio values of between 6600 and 8060 at the upper cervical spinal cord were achieved. Detection and segmentation worked reliably. An average T2 *-time of 24.88 ms ± 6.68 ms for gray matter and 19.37 ms ± 8.66 ms for white matter was calculated. CONCLUSION The proposed human brain coil can be used to image the spinal cord. The maximum in-plane resolution in this work was higher compared with the 7T results from the literature. The 9.4T acquisitions made the small structures of the spinal cord clearly visible.
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Affiliation(s)
- Ole Geldschläger
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Dario Bosch
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,Biomedical Magnetic Resonance, University Hospital Tübingen, Tübingen, Germany
| | - Nikolai I Avdievich
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Anke Henning
- High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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25
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Faillot M, Morar S, Delphine S, El-Mendili M, Ducreux D, Parker F, Aghakhani N. Prospective Follow-up of Intramedullary Slitlike Cavities: A Consecutive Series of 48 Patients. Front Neurol 2020; 11:495. [PMID: 32595590 PMCID: PMC7304370 DOI: 10.3389/fneur.2020.00495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 05/06/2020] [Indexed: 11/13/2022] Open
Abstract
Object: Predicting whether intramedullary slitlike cavity (SC) will worsen over time or remain stable is an outstanding clinical challenge. The aim of this study was to identify early features of SC (clinical and magnetic resonance imaging [MRI] findings). Methods: We prospectively included all patients referred to our institution following the discovery of a SC and divided them in two groups: typical SC (defined as a cavity spanning fewer than three vertebrae, not enlarging the spinal cord, and located at the midline between the anterior third and posterior two-thirds of the spinal cord) or atypical SC (all others). Clinical evolution and changes in MRI features were evaluated during follow-up. In some patients, diffusion tensor imaging was performed and cervical cord cross-sectional area was analyzed. Results: A total of 48 consecutive patients were included in the study. The mean follow-up was 58 months. Of the seven patients presenting with deficits at first consultation, two worsened and five remained stable. Of the 41 patients without deficits, seven worsened and 34 remained stable. None of the patients developed severe motor deficits or experienced enlargement of the cavity; 7% of patients who presented with typical SC worsened compared with 35% with atypical SC. The negative predictive value was 0.93 (P = 0.02). Conclusion: Most patients remained stable and a subset of patients developed minor motor deficits. For clinical management, we propose surveillance of patients with a typical SC and close follow-up of those with an atypical SC and/or presenting with deficits.
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Affiliation(s)
- Matthieu Faillot
- Neurosurgery Department, Bicêtre University Hospital, Assistance Publique Hôpitaux de Paris (APHP), Université Paris-Sud, Le Kremlin-Bicêtre, France
- CRMR C-MAVEM (Centre de reference Maladies Rares Chiari-Syringomyélie et Malformations vertébrales et médullaires rares/Reference Center for Rare Diseases: Chiari-Syringomyelia and Rare Malformations of the Spine and Spinal Cord), Paris, France
| | - Silvia Morar
- Neurosurgery Department, Bicêtre University Hospital, Assistance Publique Hôpitaux de Paris (APHP), Université Paris-Sud, Le Kremlin-Bicêtre, France
- CRMR C-MAVEM (Centre de reference Maladies Rares Chiari-Syringomyélie et Malformations vertébrales et médullaires rares/Reference Center for Rare Diseases: Chiari-Syringomyelia and Rare Malformations of the Spine and Spinal Cord), Paris, France
| | - Sebastien Delphine
- Biomedical imaging laboratory (LIB, Laboratoire d'Imagerie Biomédicale), CNRS, UMR 7371, INSERM, UMR-S 1146, Sorbonne Université, Paris, France
| | - Mounir El-Mendili
- Neurology Department, Icahn School of Medicine at Mount Sinaï, NewYork, NY, United States
| | - Denis Ducreux
- Neuroradiology Department, Bicêtre University Hospital, Assistance Publique Hôpitaux de Paris (APHP), Université Paris-Sud, Le Kremlin-Bicêtre, France
| | - Fabrice Parker
- Neurosurgery Department, Bicêtre University Hospital, Assistance Publique Hôpitaux de Paris (APHP), Université Paris-Sud, Le Kremlin-Bicêtre, France
- CRMR C-MAVEM (Centre de reference Maladies Rares Chiari-Syringomyélie et Malformations vertébrales et médullaires rares/Reference Center for Rare Diseases: Chiari-Syringomyelia and Rare Malformations of the Spine and Spinal Cord), Paris, France
| | - Nozar Aghakhani
- Neurosurgery Department, Bicêtre University Hospital, Assistance Publique Hôpitaux de Paris (APHP), Université Paris-Sud, Le Kremlin-Bicêtre, France
- CRMR C-MAVEM (Centre de reference Maladies Rares Chiari-Syringomyélie et Malformations vertébrales et médullaires rares/Reference Center for Rare Diseases: Chiari-Syringomyelia and Rare Malformations of the Spine and Spinal Cord), Paris, France
- *Correspondence: Nozar Aghakhani
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Gatto RG, Weissmann C, Amin M, Finkielsztein A, Sumagin R, Mareci TH, Uchitel OD, Magin RL. Assessing neuraxial microstructural changes in a transgenic mouse model of early stage Amyotrophic Lateral Sclerosis by ultra-high field MRI and diffusion tensor metrics. Animal Model Exp Med 2020; 3:117-129. [PMID: 32613171 PMCID: PMC7323706 DOI: 10.1002/ame2.12112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 02/28/2020] [Accepted: 03/22/2020] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE Cell structural changes are one of the main features observed during the development of amyotrophic lateral sclerosis (ALS). In this work, we propose the use of diffusion tensor imaging (DTI) metrics to assess specific ultrastructural changes in the central nervous system during the early neurodegenerative stages of ALS. METHODS Ultra-high field MRI and DTI data at 17.6T were obtained from fixed, excised mouse brains, and spinal cords from ALS (G93A-SOD1) mice. RESULTS Changes in fractional anisotropy (FA) and linear, planar, and spherical anisotropy ratios (CL, CP, and CS, respectively) of the diffusion eigenvalues were measured in white matter (WM) and gray matter (GM) areas associated with early axonal degenerative processes (in both the brain and the spinal cord). Specifically, in WM structures (corpus callosum, corticospinal tract, and spinal cord funiculi) as the disease progressed, FA, CL, and CP values decreased, whereas CS values increased. In GM structures (prefrontal cortex, hippocampus, and central spinal cord) FA and CP decreased, whereas the CL and CS values were unchanged or slightly smaller. Histological studies of a fluorescent mice model (YFP, G93A-SOD1 mouse) corroborated the early alterations in neuronal morphology and axonal connectivity measured by DTI. CONCLUSIONS Changes in diffusion tensor shape were observed in this animal model at the early, nonsymptomatic stages of ALS. Further studies of CL, CP, and CS as imaging biomarkers should be undertaken to refine this neuroimaging tool for future clinical use in the detection of the early stages of ALS.
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Affiliation(s)
- Rodolfo G. Gatto
- Department of BioengineeringUniversity of Illinois at ChicagoChicagoILUSA
| | - Carina Weissmann
- Instituto de Fisiología Biologia Molecular y Neurociencias‐IFIBYNE‐CONICETUniversity of Buenos AiresBuenos AiresArgentina
| | - Manish Amin
- Department of BiochemistryNational High Magnetic Field LaboratoryUniversity of FloridaGainesvilleFLUSA
| | - Ariel Finkielsztein
- Department of PathologySchool of MedicineNorthwestern UniversityChicagoILUSA
| | - Ronen Sumagin
- Department of PathologySchool of MedicineNorthwestern UniversityChicagoILUSA
| | - Thomas H. Mareci
- Department of BiochemistryNational High Magnetic Field LaboratoryUniversity of FloridaGainesvilleFLUSA
| | - Osvaldo D. Uchitel
- Instituto de Fisiología Biologia Molecular y Neurociencias‐IFIBYNE‐CONICETUniversity of Buenos AiresBuenos AiresArgentina
| | - Richard L. Magin
- Department of BioengineeringUniversity of Illinois at ChicagoChicagoILUSA
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Lévy S, Rapacchi S, Massire A, Troalen T, Feiweier T, Guye M, Callot V. Intravoxel Incoherent Motion at 7 Tesla to quantify human spinal cord perfusion: limitations and promises. Magn Reson Med 2020; 84:1198-1217. [DOI: 10.1002/mrm.28195] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 12/16/2019] [Accepted: 01/10/2020] [Indexed: 12/15/2022]
Affiliation(s)
- Simon Lévy
- Aix‐Marseille Univ, CNRS, CRMBM Marseille France
- APHM, Hopital Universitaire Timone, CEMEREM Marseille France
- Aix‐Marseille Univ, IFSTTAR, LBA Marseille France
- iLab‐Spine International Associated Laboratory Marseille‐Montreal France‐Canada
| | - Stanislas Rapacchi
- Aix‐Marseille Univ, CNRS, CRMBM Marseille France
- APHM, Hopital Universitaire Timone, CEMEREM Marseille France
| | - Aurélien Massire
- Aix‐Marseille Univ, CNRS, CRMBM Marseille France
- APHM, Hopital Universitaire Timone, CEMEREM Marseille France
- iLab‐Spine International Associated Laboratory Marseille‐Montreal France‐Canada
| | | | | | - Maxime Guye
- Aix‐Marseille Univ, CNRS, CRMBM Marseille France
- APHM, Hopital Universitaire Timone, CEMEREM Marseille France
| | - Virginie Callot
- Aix‐Marseille Univ, CNRS, CRMBM Marseille France
- APHM, Hopital Universitaire Timone, CEMEREM Marseille France
- iLab‐Spine International Associated Laboratory Marseille‐Montreal France‐Canada
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Anterior fissure, central canal, posterior septum and more: New insights into the cervical spinal cord gray and white matter regional organization using T1 mapping at 7T. Neuroimage 2020; 205:116275. [DOI: 10.1016/j.neuroimage.2019.116275] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/16/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022] Open
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Rasoanandrianina H, Massire A, Taso M, Guye M, Ranjeva JP, Kober T, Callot V. Regional T 1 mapping of the whole cervical spinal cord using an optimized MP2RAGE sequence. NMR IN BIOMEDICINE 2019; 32:e4142. [PMID: 31393649 DOI: 10.1002/nbm.4142] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 05/20/2019] [Accepted: 06/18/2019] [Indexed: 06/10/2023]
Abstract
The recently-proposed MP2RAGE sequence was purposely optimized for cervical spinal cord imaging at 3T. Sequence parameters were chosen to optimize gray/white matter T1 contrast with sub-millimetric resolution and scan-time < 10 min while preserving reliable T1 determination with minimal B1+ variation effects within a range of values compatible with pathologies and surrounding structures. Results showed good agreements with IR-based measurements, high MP2RAGE-based T1 reproducibility and preliminary evidences of age- and tract-related T1 variations in the healthy spinal cord.
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Affiliation(s)
- Henitsoa Rasoanandrianina
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
- Aix-Marseille University, IFSTTAR, LBA UMR_T24, Marseille, France
- iLab-Spine International Associated Laboratory, Marseille, France-, Montreal, Canada
| | - Aurélien Massire
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
- iLab-Spine International Associated Laboratory, Marseille, France-, Montreal, Canada
| | - Manuel Taso
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
- iLab-Spine International Associated Laboratory, Marseille, France-, Montreal, Canada
- Division of MRI Research, Department of Radiology, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, Massachusetts, USA
| | - Maxime Guye
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
| | - Jean-Philippe Ranjeva
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
- iLab-Spine International Associated Laboratory, Marseille, France-, Montreal, Canada
| | - Tobias Kober
- Advanced Clinical Imaging Technology, Siemens Healthcare, Lausanne, Switzerland
- Department of Radiology, Centre Hospitalier Universitaire Vaudois (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
- Signal Processing Laboratory (LTS 5), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Virginie Callot
- Aix-Marseille University, CNRS, CRMBM, Marseille, France
- APHM, Hôpital Universitaire Timone, CEMEREM, Marseille, France
- iLab-Spine International Associated Laboratory, Marseille, France-, Montreal, Canada
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Cadotte DW, Akbar MA, Fehlings MG, Stroman PW, Cohen-Adad J. What Has Been Learned from Magnetic Resonance Imaging Examination of the Injured Human Spinal Cord: A Canadian Perspective. J Neurotrauma 2019; 35:1942-1957. [PMID: 30074873 DOI: 10.1089/neu.2018.5903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Magnetic resonance imaging (MRI) has transformed the way surgeons and researchers study and treat spinal cord injury. In this narrative review, we explore the historical context of imaging the human spinal cord and describe how MRI has evolved from providing the first visualization of the human spinal cord in the 1980s to a remarkable set of imaging tools today. The article focuses in particular on the role of Canadian researchers to this field. We begin by outlining the clinical context of traumatic injury to the human spinal cord and describe why current MRI standards fall short when it comes to treating this disabling condition. Parts 2 and 3 of this work explore an exciting and dramatic shift in the use of MRI technology to aid in our understanding and treatment of traumatic injury to the spinal cord. We explore the use of functional imaging (part 2) and structural imaging (part 3) and explore how these techniques have evolved, how they are used, and the challenges that we face for continued refinement and application to patients who live with the neurological and functional deficits caused by injury to the delicate spinal cord.
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Affiliation(s)
- David W Cadotte
- 1 University of Calgary Spine Program, Division of Neurosurgery, Department of Clinical Neurosciences, University of Calgary , Foothills Medical Centre, Calgary, Alberta, Canada
| | - M Ali Akbar
- 2 Department of Surgery, Division of Neurosurgery and Spinal Program, Toronto Western Hospital, University of Toronto , Toronto, Ontario, Canada
| | - Michael G Fehlings
- 2 Department of Surgery, Division of Neurosurgery and Spinal Program, Toronto Western Hospital, University of Toronto , Toronto, Ontario, Canada
| | - Patrick W Stroman
- 3 Centre for Neuroscience Studies, Queens University , Kingston, Ontario, Canada
| | - Julien Cohen-Adad
- 4 NeuroPoly Lab, Institute of Biomedical Engineering , Polytechnique Montreal, Montreal, Quebéc, Canada .,5 Functional Neuroimaging Unit, CRIUGM, Université de Montréal , Montreal, Quebéc, Canada
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Barry RL, Smith SA. Measurement of T 2* in the human spinal cord at 3T. Magn Reson Med 2019; 82:743-748. [PMID: 30924198 PMCID: PMC6510624 DOI: 10.1002/mrm.27755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 03/06/2019] [Accepted: 03/06/2019] [Indexed: 12/18/2022]
Abstract
PURPOSE To measure the transverse relaxation time T2* in healthy human cervical spinal cord gray matter (GM) and white matter (WM) at 3T. METHODS Thirty healthy volunteers were recruited. Axial images were acquired using an averaged multi-echo gradient-echo (mFFE) T2*-weighted sequence with 5 echoes. We used the signal equation for an mFFE sequence with constant dephasing gradients after each echo to jointly estimate the spin density and T2* for each voxel. RESULTS No global difference in T2* was observed between all GM (41.3 ± 5.6 ms) and all WM (39.8 ± 5.4 ms). No significant differences were observed between left (43.2 ± 6.8 ms) and right (43.4 ± 5.5 ms) ventral GM, left (38.3 ± 6.1 ms) and right (38.6 ± 6.5 ms) dorsal GM, and left (39.4 ± 5.8 ms) and right (40.3 ± 5.8 ms) lateral WM. However, significant regional differences were observed between ventral (43.4 ± 5.7 ms) and dorsal (38.4 ± 6.0 ms) GM (p < 0.05), as well as between ventral (42.9 ± 6.5 ms) and dorsal (37.9 ± 6.2 ms) WM (p < 0.05). In analyses across slices, inferior T2* was longer than superior T2* in GM (44.7 ms vs. 40.1 ms; p < 0.01) and in WM (41.8 ms vs. 35.9 ms; p < 0.01). CONCLUSIONS Significant differences in T2* are observed between ventral and dorsal GM, ventral and dorsal WM, and superior and inferior GM and WM. There is no evidence for bilateral asymmetry in T2* in the healthy cord. These values of T2* in the spinal cord are notably lower than most reported values of T2* in the cortex.
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Affiliation(s)
- Robert L. Barry
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA,Department of Radiology, Harvard Medical School, Boston, MA, USA,Harvard-Massachusetts Institute of Technology Health Sciences & Technology, Cambridge, MA, USA
| | - Seth A. Smith
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA,Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
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Vannesjo SJ, Clare S, Kasper L, Tracey I, Miller KL. A method for correcting breathing-induced field fluctuations in T2*-weighted spinal cord imaging using a respiratory trace. Magn Reson Med 2019; 81:3745-3753. [PMID: 30737825 PMCID: PMC6492127 DOI: 10.1002/mrm.27664] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 12/01/2018] [Accepted: 12/27/2018] [Indexed: 02/04/2023]
Abstract
PURPOSE Spinal cord MRI at ultrahigh field is hampered by time-varying magnetic fields associated with the breathing cycle, giving rise to ghosting artifacts in multi-shot acquisitions. Here, we suggest a correction approach based on linking the signal from a respiratory bellows to field changes inside the spinal cord. The information is used to correct the data at the image reconstruction level. METHODS The correction was demonstrated in the context of multi-shot T2*-weighted imaging of the cervical spinal cord at 7T. A respiratory trace was acquired during a high-resolution multi-echo gradient-echo sequence, used for structural imaging and quantitative T2* mapping, and a multi-shot EPI time series, as would be suitable for fMRI. The coupling between the trace and the breathing-induced fields was determined by a short calibration scan in each individual. Images were reconstructed with and without trace-based correction. RESULTS In the multi-echo acquisition, breathing-induced fields caused severe ghosting in images with long TE, which led to a systematic underestimation of T2* in the spinal cord. The trace-based correction reduced the ghosting and increased the estimated T2* values. Breathing-related ghosting was also observed in the multi-shot EPI images. The correction largely removed the ghosting, thereby improving the temporal signal-to-noise ratio of the time series. CONCLUSIONS Trace-based retrospective correction of breathing-induced field variations can reduce ghosting and improve quantitative metrics in multi-shot structural and functional T2*-weighted imaging of the spinal cord. The method is straightforward to implement and does not rely on sequence modifications or additional hardware beyond a respiratory bellows.
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Affiliation(s)
- S. Johanna Vannesjo
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Stuart Clare
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Lars Kasper
- Institute for Biomedical EngineeringETH Zurich and University of ZurichZurichSwitzerland
- Translational Neuromodeling Unit, Institute for Biomedical EngineeringUniversity of Zurich and ETH ZurichZurichSwitzerland
| | - Irene Tracey
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Karla L. Miller
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
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Abstract
Persistent spinal (traumatic and nontraumatic) pain is common and contributes to high societal and personal costs globally. There is an acknowledged urgency for new and interdisciplinary approaches to the condition, and soft tissues, including skeletal muscles, the spinal cord, and the brain, are rightly receiving increased attention as important biological contributors. In reaction to the recent suspicion and questioned value of imaging-based findings, this paper serves to recognize the promise that the technological evolution of imaging techniques, and particularly magnetic resonance imaging, is allowing in characterizing previously less visible morphology. We emphasize the value of quantification and data analysis of several contributors in the biopsychosocial model for understanding spinal pain. Further, we highlight emerging evidence regarding the pathobiology of changes to muscle composition (eg, atrophy, fatty infiltration), as well as advancements in neuroimaging and musculoskeletal imaging techniques (eg, fat-water imaging, functional magnetic resonance imaging, diffusion imaging, magnetization transfer imaging) for these important soft tissues. These noninvasive and objective data sources may complement known prognostic factors of poor recovery, patient self-report, diagnostic tests, and the "-omics" fields. When combined, advanced "big-data" analyses may assist in identifying associations previously not considered. Our clinical commentary is supported by empirical findings that may orient future efforts toward collaborative conversation, hypothesis generation, interdisciplinary research, and translation across a number of health fields. Our emphasis is that magnetic resonance imaging technologies and research are crucial to the advancement of our understanding of the complexities of spinal conditions. J Orthop Sports Phys Ther 2019;49(5):320-329. Epub 26 Mar 2019. doi:10.2519/jospt.2019.8793.
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Moccia M, Ruggieri S, Ianniello A, Toosy A, Pozzilli C, Ciccarelli O. Advances in spinal cord imaging in multiple sclerosis. Ther Adv Neurol Disord 2019; 12:1756286419840593. [PMID: 31040881 PMCID: PMC6477770 DOI: 10.1177/1756286419840593] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/03/2019] [Indexed: 11/18/2022] Open
Abstract
The spinal cord is frequently affected in multiple sclerosis (MS), causing motor, sensory and autonomic dysfunction. A number of pathological abnormalities, including demyelination and neuroaxonal loss, occur in the MS spinal cord and are studied in vivo with magnetic resonance imaging (MRI). The aim of this review is to summarise and discuss recent advances in spinal cord MRI. Advances in conventional spinal cord MRI include improved identification of MS lesions, recommended spinal cord MRI protocols, enhanced recognition of MRI lesion characteristics that allow MS to be distinguished from other myelopathies, evidence for the role of spinal cord lesions in predicting prognosis and monitoring disease course, and novel post-processing methods to obtain lesion probability maps. The rate of spinal cord atrophy is greater than that of brain atrophy (-1.78% versus -0.5% per year), and reflects neuroaxonal loss in an eloquent site of the central nervous system, suggesting that it can become an important outcome measure in clinical trials, especially in progressive MS. Recent developments allow the calculation of spinal cord atrophy from brain volumetric scans and evaluation of its progression over time with registration-based techniques. Fully automated analysis methods, including segmentation of grey matter and intramedullary lesions, will facilitate the use of spinal cord atrophy in trial designs and observational studies. Advances in quantitative imaging techniques to evaluate neuroaxonal integrity, myelin content, metabolic changes, and functional connectivity, have provided new insights into the mechanisms of damage in MS. Future directions of research and the possible impact of 7T scanners on spinal cord imaging will be discussed.
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Affiliation(s)
- Marcello Moccia
- Queen Square MS Centre, NMR Research Unit, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
- Multiple Sclerosis Clinical Care and Research Centre, Department of Neurosciences, Federico II University of Naples, via Sergio Pansini, 5, Edificio 17 - piano terra, Napoli, 80131 Naples, Italy
| | - Serena Ruggieri
- Department of Human Neuroscience, Sapienza University of Rome, Italy
| | - Antonio Ianniello
- Department of Human Neuroscience, Sapienza University of Rome, Italy
| | - Ahmed Toosy
- Queen Square MS Centre, NMR Research Unit, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
| | - Carlo Pozzilli
- Department of Human Neuroscience, Sapienza University of Rome, Italy
| | - Olga Ciccarelli
- Queen Square MS Centre, NMR Research Unit, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
- National Institute for Health Research, University College London Hospitals Biomedical Research Centre, London, UK
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35
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Rietsch SHG, Brunheim S, Orzada S, Voelker MN, Maderwald S, Bitz AK, Gratz M, Ladd ME, Quick HH. Development and evaluation of a 16-channel receive-only RF coil to improve 7T ultra-high field body MRI with focus on the spine. Magn Reson Med 2019; 82:796-810. [PMID: 30924181 DOI: 10.1002/mrm.27731] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/02/2019] [Accepted: 01/27/2019] [Indexed: 12/21/2022]
Abstract
PURPOSE A 16-channel receive (16Rx) radiofrequency (RF) array for 7T ultra-high field body MR imaging is presented. The coil is evaluated in conjunction with a 16-channel transmit/receive (16TxRx) coil and additionally with a 32-channel transmit/receive (32TxRx) remote body coil for RF transmit and serving as receive references. METHODS The 16Rx array consists of 16 octagonal overlapping loops connected to custom-built detuning boards with preamplifiers. Performance metrics like noise correlation, g-factors, and signal-to-noise ratio gain were compared between 4 different RF coil configurations. In vivo body imaging was performed in volunteers using radiofrequency shimming, time interleaved acquisition of modes (TIAMO), and 2D spatially selective excitation using parallel transmit (pTx) in the spine. RESULTS Lower g-factors were obtained when using the 16Rx coil in addition to the 16TxRx array coil configuration versus the 16TxRx array alone. Distinct signal-to-noise ratio gain using the 16Rx coil could be demonstrated in the spine region both for a comparison with the 16TxRx coil (>50% gain) in vivo and the 32TxRx coil (>240% gain) in a phantom. The 16Rx coil was successfully applied to improve anatomical imaging in the abdomen and 2D spatially selective excitation in the spine of volunteers. CONCLUSION The novel 16-channel Rx-array as an add-on to multichannel TxRx RF coil configurations provides increased signal-to-noise ratio, lower g-factors, and thus improves 7T ultra-high field body MR imaging.
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Affiliation(s)
- Stefan H G Rietsch
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
| | - Sascha Brunheim
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
| | - Stephan Orzada
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany
| | - Maximilian N Voelker
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
| | - Stefan Maderwald
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany
| | - Andreas K Bitz
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Electromagnetic Theory and Applied Mathematics, Faculty of Electrical Engineering and Information Technology, University of Applied Sciences Aachen, Aachen, Germany
| | - Marcel Gratz
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
| | - Mark E Ladd
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Physics and Astronomy and Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
| | - Harald H Quick
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Essen, Germany.,High-Field and Hybrid MR Imaging, University Hospital Essen, Essen, Germany
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A practical protocol for measurements of spinal cord functional connectivity. Sci Rep 2018; 8:16512. [PMID: 30410122 PMCID: PMC6224587 DOI: 10.1038/s41598-018-34841-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 10/25/2018] [Indexed: 11/08/2022] Open
Abstract
Resting state functional magnetic resonance imaging (fMRI) has been used to study human brain function for over two decades, but only recently has this technique been successfully translated to the human spinal cord. The spinal cord is structurally and functionally unique, so resting state fMRI methods developed and optimized for the brain may not be appropriate when applied to the cord. This report therefore investigates the relative impact of different acquisition and processing choices (including run length, echo time, and bandpass filter width) on the detectability of resting state spinal cord networks at 3T. Our results suggest that frequencies beyond 0.08 Hz should be included in resting state analyses, a run length of ~8-12 mins is appropriate for reliable detection of the ventral (motor) network, and longer echo times - yet still shorter than values typically used for fMRI in the brain - may increase the detectability of the dorsal (sensory) network. Further studies are required to more fully understand and interpret the nature of resting state spinal cord networks in health and in disease, and the protocols described in this report are designed to assist such studies.
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37
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Cohen-Adad J. Microstructural imaging in the spinal cord and validation strategies. Neuroimage 2018; 182:169-183. [PMID: 29635029 DOI: 10.1016/j.neuroimage.2018.04.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 03/02/2018] [Accepted: 04/06/2018] [Indexed: 12/13/2022] Open
Abstract
In vivo histology using magnetic resonance imaging (MRI) is a newly emerging research field that aims to non-invasively characterize tissue microstructure. The implications of in vivo histology are many, from discovering novel biomarkers to studying human development, to providing tools for disease diagnosis and monitoring the effects of novel treatments on tissue. This review focuses on quantitative MRI (qMRI) techniques that are used to map spinal cord microstructure. Opening with a rationale for non-invasive imaging of the spinal cord, this article continues with a brief overview of the existing MRI techniques for axon and myelin imaging, followed by the specific challenges and potential solutions for acquiring and processing such data. The final part of this review focuses on histological validation, with suggested tissue preparation, acquisition and processing protocols for large-scale microscopy.
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Affiliation(s)
- J Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada.
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Effect of cardiac-related translational motion in diffusion MRI of the spinal cord. Magn Reson Imaging 2018; 50:119-124. [PMID: 29626518 DOI: 10.1016/j.mri.2018.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/30/2018] [Accepted: 04/03/2018] [Indexed: 11/22/2022]
Abstract
Cardiac-related spinal cord motion affects diffusion-weighted (DWI) signal. The goal of this study was to further quantify the specific detrimental effect of cord translational motion on the DWI signal in order to make better informed decisions about the cost-benefit of cardiac gating. We designed an MRI-compatible phantom mimicking the spinal cord translational motion. Cardiac-gated DWI data were acquired by varying the trigger delay and the b-values. Evaluation of the effect of motion on the DWI signal was done by computing the apparent diffusion coefficient (ADC) along (z-direction) and orthogonal (y- and x-directions) to the phantom. The computed ADCs of the phantom moving along Z were similar for the three orthogonal diffusion-encoding directions, with an average value of 1.65·10-9 , 1.66·10-9 and 1.65·10-9 m2/s along X, Y and Z respectively. DW phase images on the other hand showed the expected linear relationship with phantom velocity. Pure translational motion has minor effect on the diffusion-weighted magnitude signal. The sudden signal drop typically observed in in vivo spinal cord DWI is likely not caused by translational motion of the spinal cord, and possibly originates from non-rigid compression/stretching of the cord and/or from intra-voxel incoherent motion (IVIM).
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Calabrese E, Adil SM, Cofer G, Perone CS, Cohen-Adad J, Lad SP, Johnson GA. Postmortem diffusion MRI of the entire human spinal cord at microscopic resolution. Neuroimage Clin 2018; 18:963-971. [PMID: 29876281 PMCID: PMC5988447 DOI: 10.1016/j.nicl.2018.03.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 01/15/2018] [Accepted: 03/21/2018] [Indexed: 11/20/2022]
Abstract
The human spinal cord is a central nervous system structure that plays an important role in normal motor and sensory function, and can be affected by many debilitating neurologic diseases. Due to its clinical importance, the spinal cord is frequently the subject of imaging research. Common methods for visualizing spinal cord anatomy and pathology include histology and magnetic resonance imaging (MRI), both of which have unique benefits and drawbacks. Postmortem microscopic resolution MRI of fixed specimens, sometimes referred to as magnetic resonance microscopy (MRM), combines many of the benefits inherent to both techniques. However, the elongated shape of the human spinal cord, along with hardware and scan time limitations, have restricted previous microscopic resolution MRI studies (both in vivo and ex vivo) to small sections of the cord. Here we present the first MRM dataset of the entire postmortem human spinal cord. These data include 50 μm isotropic resolution anatomic image data and 100 μm isotropic resolution diffusion data, made possible by a 280 h long multi-segment acquisition and automated image segment composition. We demonstrate the use of these data for spinal cord lesion detection, automated volumetric gray matter segmentation, and quantitative spinal cord morphometry including estimates of cross sectional dimensions and gray matter fraction throughout the length of the cord.
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Affiliation(s)
- Evan Calabrese
- Department of Radiology & Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA; Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA.
| | - Syed M Adil
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA; Department of Neurosurgery, Duke University Medical Center, Durham, NC, USA
| | - Gary Cofer
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA
| | - Christian S Perone
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - Shivanand P Lad
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, USA
| | - G Allan Johnson
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, USA
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Drake-Pérez M, Delattre BMA, Boto J, Fitsiori A, Lovblad KO, Boudabbous S, Vargas MI. Normal Values of Magnetic Relaxation Parameters of Spine Components with the Synthetic MRI Sequence. AJNR Am J Neuroradiol 2018; 39:788-795. [PMID: 29496723 DOI: 10.3174/ajnr.a5566] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 12/12/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE SyMRI is a technique developed to perform quantitative MR imaging. Our aim was to analyze its potential use for measuring relaxation times of normal components of the spine and to compare them with values found in the literature using relaxometry and other techniques. MATERIALS AND METHODS Thirty-two spine MR imaging studies (10 cervical, 5 dorsal, 17 lumbosacral) were included. A modified multiple-dynamic multiple-echo sequence was added and processed to obtain quantitative T1 (millisecond), T2 (millisecond), and proton density (percentage units [pu]) maps for each patient. An ROI was placed on representative areas for CSF, spinal cord, intervertebral discs, and vertebral bodies, to measure their relaxation. RESULTS Relaxation time means are reported for CSF (T1 = 4273.4 ms; T2 = 1577.6 ms; proton density = 107.5 pu), spinal cord (T1 = 780.2 ms; T2 = 101.6 ms; proton density = 58.7 pu), normal disc (T1 = 1164.9 ms; T2 = 101.9 ms; proton density = 78.9 pu), intermediately hydrated disc (T1 = 723 ms; T2 = 66.8 ms; proton density = 60.8 pu), desiccated disc (T1 = 554.4 ms; T2 = 55.6 ms; proton density = 47.6 ms), and vertebral body (T1 = 515.3 ms; T2 = 100.8 ms; proton density = 91.1 pu). Comparisons among the mean T1, T2, and proton density values showed significant differences between different spinal levels (cervical, dorsal, lumbar, and sacral) for CSF (proton density), spinal cord (T2 and proton density), normal disc (T1, T2, and proton density), and vertebral bodies (T1 and proton density). Significant differences were found among mean T1, T2, and proton density values of normal, intermediately hydrated, and desiccated discs. CONCLUSIONS Measurements can be easily obtained on SyMRI and correlated with previously published values obtained using conventional relaxometry techniques.
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Affiliation(s)
- M Drake-Pérez
- From the Division of Diagnostic and Interventional Neuroradiology (M.D.-P., J.B., A.F., K.-O.L., M.I.V.), Geneva University Hospitals and Faculty of Medicine of Geneva, Geneva, Switzerland.,Department of Radiology (M.D.-P.), University Hospital Marqués de Valdecilla-Instituto de Investigación Sanitaria Valdecilla, Santander, Spain
| | - B M A Delattre
- Division of Radiology (B.M.A.D., S.B.), Geneva University Hospitals, Geneva, Switzerland
| | - J Boto
- From the Division of Diagnostic and Interventional Neuroradiology (M.D.-P., J.B., A.F., K.-O.L., M.I.V.), Geneva University Hospitals and Faculty of Medicine of Geneva, Geneva, Switzerland
| | - A Fitsiori
- From the Division of Diagnostic and Interventional Neuroradiology (M.D.-P., J.B., A.F., K.-O.L., M.I.V.), Geneva University Hospitals and Faculty of Medicine of Geneva, Geneva, Switzerland
| | - K-O Lovblad
- From the Division of Diagnostic and Interventional Neuroradiology (M.D.-P., J.B., A.F., K.-O.L., M.I.V.), Geneva University Hospitals and Faculty of Medicine of Geneva, Geneva, Switzerland
| | - S Boudabbous
- Division of Radiology (B.M.A.D., S.B.), Geneva University Hospitals, Geneva, Switzerland
| | - M I Vargas
- From the Division of Diagnostic and Interventional Neuroradiology (M.D.-P., J.B., A.F., K.-O.L., M.I.V.), Geneva University Hospitals and Faculty of Medicine of Geneva, Geneva, Switzerland
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41
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Barry RL, Vannesjo SJ, By S, Gore JC, Smith SA. Spinal cord MRI at 7T. Neuroimage 2018; 168:437-451. [PMID: 28684332 PMCID: PMC5894871 DOI: 10.1016/j.neuroimage.2017.07.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 06/30/2017] [Accepted: 07/02/2017] [Indexed: 11/25/2022] Open
Abstract
Magnetic resonance imaging (MRI) of the human spinal cord at 7T has been demonstrated by a handful of research sites worldwide, and the spinal cord remains one of the areas in which higher fields and resolution could have high impact. The small diameter of the cord (∼1 cm) necessitates high spatial resolution to minimize partial volume effects between gray and white matter, and so MRI of the cord can greatly benefit from increased signal-to-noise ratio and contrasts at ultra-high field (UHF). Herein we review the current state of UHF spinal cord imaging. Technical challenges to successful UHF spinal cord MRI include radiofrequency (B1) nonuniformities and a general lack of optimized radiofrequency coils, amplified physiological noise, and an absence of methods for robust B0 shimming along the cord to mitigate image distortions and signal losses. Numerous solutions to address these challenges have been and are continuing to be explored, and include novel approaches for signal excitation and acquisition, dynamic shimming and specialized shim coils, and acquisitions with increased coverage or optimal slice angulations.
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Affiliation(s)
- Robert L Barry
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA.
| | - S Johanna Vannesjo
- Oxford Centre for Functional MRI of the Brain (FMRIB), Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Samantha By
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - John C Gore
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Seth A Smith
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
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Massire A, Rasoanandrianina H, Taso M, Guye M, Ranjeva JP, Feiweier T, Callot V. Feasibility of single-shot multi-level multi-angle diffusion tensor imaging of the human cervical spinal cord at 7T. Magn Reson Med 2018; 80:947-957. [DOI: 10.1002/mrm.27087] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/07/2017] [Accepted: 12/26/2017] [Indexed: 01/11/2023]
Affiliation(s)
- Aurélien Massire
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
- iLab-Spine - Laboratoire international associé - Imagerie et Biomécanique du rachis, France; Canada
| | - Henitsoa Rasoanandrianina
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
- iLab-Spine - Laboratoire international associé - Imagerie et Biomécanique du rachis, France; Canada
| | - Manuel Taso
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
- iLab-Spine - Laboratoire international associé - Imagerie et Biomécanique du rachis, France; Canada
- Division of MRI Research, Department of Radiology; Beth Israel Deaconess Medical Center & Harvard Medical School; Boston Massachusetts USA
| | - Maxime Guye
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
| | - Jean-Philippe Ranjeva
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
- iLab-Spine - Laboratoire international associé - Imagerie et Biomécanique du rachis, France; Canada
| | | | - Virginie Callot
- Aix-Marseille Univ, CNRS, AP-HM, CRMBM, Hôpital de la Timone; CEMEREM Marseille France
- iLab-Spine - Laboratoire international associé - Imagerie et Biomécanique du rachis, France; Canada
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PAM50: Unbiased multimodal template of the brainstem and spinal cord aligned with the ICBM152 space. Neuroimage 2018; 165:170-179. [DOI: 10.1016/j.neuroimage.2017.10.041] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/16/2017] [Accepted: 10/20/2017] [Indexed: 11/17/2022] Open
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Battiston M, Schneider T, Prados F, Grussu F, Yiannakas MC, Ourselin S, Gandini Wheeler-Kingshott CAM, Samson RS. Fast and reproducible in vivo T 1 mapping of the human cervical spinal cord. Magn Reson Med 2017; 79:2142-2148. [PMID: 28736946 DOI: 10.1002/mrm.26852] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/04/2017] [Accepted: 07/05/2017] [Indexed: 12/16/2022]
Abstract
PURPOSE To develop a fast and robust method for measuring T1 in the whole cervical spinal cord in vivo, and to assess its reproducibility. METHODS A spatially nonselective adiabatic inversion pulse is combined with zonally oblique-magnified multislice echo-planar imaging to produce a reduced field-of-view inversion-recovery echo-planar imaging protocol. Multi- inversion time data are obtained by cycling slice order throughout sequence repetitions. Measurement of T1 is performed using 12 inversion times for a total protocol duration of 7 min. Reproducibility of regional T1 estimates is assessed in a scan-rescan experiment on five heathy subjects. RESULTS Regional mean (standard deviation) T1 was: 1108.5 (±77.2) ms for left lateral column, 1110.1 (±83.2) ms for right lateral column, 1150.4 (±102.6) ms for dorsal column, and 1136.4 (±90.8) ms for gray matter. Regional T1 estimates showed good correlation between sessions (Pearson correlation coefficient = 0.89 (P value < 0.01); mean difference = 2 ms, 95% confidence interval ± 20 ms); and high reproducibility (intersession coefficient of variation approximately 1% in all the regions considered, intraclass correlation coefficient = 0.88 (P value < 0.01, confidence interval 0.71-0.95)). CONCLUSIONS T1 estimates in the cervical spinal cord are reproducible using inversion-recovery zonally oblique-magnified multislice echo-planar imaging. The short acquisition time and large coverage of this method paves the way for accurate T1 mapping for various spinal cord pathologies. Magn Reson Med 79:2142-2148, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
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Affiliation(s)
- Marco Battiston
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom
| | | | - Ferran Prados
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom.,Translational Imaging Group, Center for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Francesco Grussu
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Marios C Yiannakas
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Sebastien Ourselin
- Translational Imaging Group, Center for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Claudia A M Gandini Wheeler-Kingshott
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom.,Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Brain MRI 3T Mondino Research Center, C. Mondino National Neurological Institute, Pavia, Italy
| | - Rebecca S Samson
- NMR Research Unit, Queen Square MS Center, Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, United Kingdom
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Vargas MI, Boto J, Dammann P, Lovblad KO. High-Resolution Hybrid Imaging Could Improve Cordotomy Lesions and Outcomes. AJNR Am J Neuroradiol 2017; 38:E78. [PMID: 28572148 DOI: 10.3174/ajnr.a5269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | - J Boto
- Division of Neuroradiology, DISIM
| | | | - K-O Lovblad
- Division of Neuroradiology, DISIM Geneva University Hospital Geneva, Switzerland
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46
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De Leener B, Lévy S, Dupont SM, Fonov VS, Stikov N, Louis Collins D, Callot V, Cohen-Adad J. SCT: Spinal Cord Toolbox, an open-source software for processing spinal cord MRI data. Neuroimage 2016; 145:24-43. [PMID: 27720818 DOI: 10.1016/j.neuroimage.2016.10.009] [Citation(s) in RCA: 338] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 10/03/2016] [Accepted: 10/04/2016] [Indexed: 11/17/2022] Open
Abstract
For the past 25 years, the field of neuroimaging has witnessed the development of several software packages for processing multi-parametric magnetic resonance imaging (mpMRI) to study the brain. These software packages are now routinely used by researchers and clinicians, and have contributed to important breakthroughs for the understanding of brain anatomy and function. However, no software package exists to process mpMRI data of the spinal cord. Despite the numerous clinical needs for such advanced mpMRI protocols (multiple sclerosis, spinal cord injury, cervical spondylotic myelopathy, etc.), researchers have been developing specific tools that, while necessary, do not provide an integrative framework that is compatible with most usages and that is capable of reaching the community at large. This hinders cross-validation and the possibility to perform multi-center studies. In this study we introduce the Spinal Cord Toolbox (SCT), a comprehensive software dedicated to the processing of spinal cord MRI data. SCT builds on previously-validated methods and includes state-of-the-art MRI templates and atlases of the spinal cord, algorithms to segment and register new data to the templates, and motion correction methods for diffusion and functional time series. SCT is tailored towards standardization and automation of the processing pipeline, versatility, modularity, and it follows guidelines of software development and distribution. Preliminary applications of SCT cover a variety of studies, from cross-sectional area measures in large databases of patients, to the precise quantification of mpMRI metrics in specific spinal pathways. We anticipate that SCT will bring together the spinal cord neuroimaging community by establishing standard templates and analysis procedures.
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Affiliation(s)
- Benjamin De Leener
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - Simon Lévy
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada
| | - Sara M Dupont
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | - Vladimir S Fonov
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Nikola Stikov
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Montreal Heart Institute, Montreal, QC, Canada
| | - D Louis Collins
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Virginie Callot
- Aix-Marseille Université, CNRS, CRMBM UMR 7339, Marseille, France; AP-HM, Hopital de la Timone, Pôle d'imagerie médicale, CEMEREM, Marseille, France
| | - Julien Cohen-Adad
- NeuroPoly Lab, Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada; Functional Neuroimaging Unit, CRIUGM, Université de Montréal, Montreal, QC, Canada.
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