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Filimonova E, Letyagin V, Zaitsev B, Kubetsky Y, Rzaev J. Application of the T1w/T2w mapping technique for spinal cord assessment in patients with degenerative cervical myelopathy. Spinal Cord 2024; 62:6-11. [PMID: 37919382 DOI: 10.1038/s41393-023-00941-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 10/18/2023] [Accepted: 10/24/2023] [Indexed: 11/04/2023]
Abstract
STUDY DESIGN Retrospective case-control study. OBJECTIVES To investigate signal changes on T1w/T2w signal intensity ratio maps within cervical cord in patients with degenerative cervical myelopathy (DCM). SETTING Novosibirsk Neurosurgery Center, Russia. METHODS A total of 261 patients with DCM and 42 age- and sex-matched healthy controls were evaluated using the T1w/T2w mapping method and spinal cord automatic morphometry. The T1w/T2w signal intensity ratio, which reflects white matter integrity, and the spinal cord cross-sectional area (CSA) were calculated and compared between the patients and the controls. In patients with DCM, the correlations between these parameters and neurological scores were also evaluated. RESULTS The regional T1w/T2w ratio values from the cervical spinal cord at the level of maximal compression in patients with DCM were significantly lower than those in healthy controls (p < 0.001), as were the regional CSA values (p < 0.001). There was a positive correlation between the regional values of the T1w/T2w ratio and the values of the CSA at the level of maximal spinal cord compression. CONCLUSIONS T1w/T2w mapping revealed that spinal cord tissue damage exists at the level of maximal compression in patients with DCM in association with spinal cord atrophy according to automatic morphometry. These changes were correlated with each other.
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Affiliation(s)
- Elena Filimonova
- Federal Center of Neurosurgery Novosibirsk, Novosibirsk, Russia.
- Novosibirsk State Medical University, Novosibirsk, Russia.
| | | | - Boris Zaitsev
- Federal Center of Neurosurgery Novosibirsk, Novosibirsk, Russia
| | - Yulij Kubetsky
- Federal Center of Neurosurgery Novosibirsk, Novosibirsk, Russia
| | - Jamil Rzaev
- Federal Center of Neurosurgery Novosibirsk, Novosibirsk, Russia
- Novosibirsk State Medical University, Novosibirsk, Russia
- Department of Neuroscience, Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
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Filimonova E, Amelina E, Sazonova A, Zaitsev B, Rzaev J. Assessment of normal myelination in infants and young children using the T1w/T2w mapping technique. Front Neurosci 2023; 17:1102691. [PMID: 36925743 PMCID: PMC10011126 DOI: 10.3389/fnins.2023.1102691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 02/13/2023] [Indexed: 03/04/2023] Open
Abstract
Background White matter myelination is a crucial process of CNS maturation. The purpose of this study was to validate the T1w/T2w mapping technique for brain myelination assessment in infants and young children. Methods Ninety-four patients (0-23 months of age) without structural abnormalities on brain MRI were evaluated by using the T1w/T2w mapping method. The T1w/T2w signal intensity ratio, which reflects white matter integrity and the degree of myelination, was calculated in various brain regions. We performed a Pearson correlation analysis, a LOESS regression analysis, and a 2nd order polynomial regression analysis to describe the relationships between the regional metrics and the age of the patients (in months). Results T1w/T2w ratio values rapidly increased in the first 6-9 months of life and then slowed thereafter. The T1w/T2w mapping technique emphasized the contrast between myelinated and less myelinated structures in all age groups, which resulted in better visualization. There were strong positive correlations between the T1w/T2w ratio values from the majority of white matter ROIs and the subjects' age (R = 0.7-0.9, p < 0.001). Within all of the analyzed regions, there were non-linear relationships between age and T1/T2 ratio values that varied by anatomical and functional location. Regions such as the splenium and the genu of the corpus callosum showed the highest R2 values, thus indicating less scattering of data and a better fit to the model. Conclusion The T1w/T2w mapping technique may enhance our diagnostic ability to assess myelination patterns in the brains of infants and young children.
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Affiliation(s)
- Elena Filimonova
- Federal Center of Neurosurgery, Novosibirsk, Russia.,Department of Neurosurgery, Novosibirsk State Medical University, Novosibirsk, Russia
| | - Evgenia Amelina
- Stream Data Analytics and Machine Learning Laboratory, Novosibirsk State University, Novosibirsk, Russia
| | - Aleksandra Sazonova
- Federal Center of Neurosurgery, Novosibirsk, Russia.,Department of Neuroscience, Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
| | - Boris Zaitsev
- Federal Center of Neurosurgery, Novosibirsk, Russia.,Department of Neuroscience, Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
| | - Jamil Rzaev
- Federal Center of Neurosurgery, Novosibirsk, Russia.,Department of Neurosurgery, Novosibirsk State Medical University, Novosibirsk, Russia.,Department of Neuroscience, Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
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Combes AJ, Clarke MA, O'Grady KP, Schilling KG, Smith SA. Advanced spinal cord MRI in multiple sclerosis: Current techniques and future directions. Neuroimage Clin 2022; 36:103244. [PMID: 36306717 PMCID: PMC9668663 DOI: 10.1016/j.nicl.2022.103244] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 09/02/2022] [Accepted: 10/19/2022] [Indexed: 11/11/2022]
Abstract
Spinal cord magnetic resonance imaging (MRI) has a central role in multiple sclerosis (MS) clinical practice for diagnosis and disease monitoring. Advanced MRI sequences capable of visualizing and quantifying tissue macro- and microstructure and reflecting different pathological disease processes have been used in MS research; however, the spinal cord remains under-explored, partly due to technical obstacles inherent to imaging this structure. We propose that the study of the spinal cord merits equal ambition in overcoming technical challenges, and that there is much information to be exploited to make valuable contributions to our understanding of MS. We present a narrative review on the latest progress in advanced spinal cord MRI in MS, covering in the first part structural, functional, metabolic and vascular imaging methods. We focus on recent studies of MS and those making significant technical steps, noting the challenges that remain to be addressed and what stands to be gained from such advances. Throughout we also refer to other works that presend more in-depth review on specific themes. In the second part, we present several topics that, in our view, hold particular potential. The need for better imaging of gray matter is discussed. We stress the importance of developing imaging beyond the cervical spinal cord, and explore the use of ultra-high field MRI. Finally, some recommendations are given for future research, from study design to newer developments in analysis, and the need for harmonization of sequences and methods within the field. This review is aimed at researchers and clinicians with an interest in gaining an overview of the current state of advanced MRI research in this field and what is primed to be the future of spinal cord imaging in MS research.
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Affiliation(s)
- Anna J.E. Combes
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, 1161 21st Avenue South, Medical Center North, AA-1105, Nashville, TN 37232-2310, United States,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Medical Center North, 1161 21st Ave. South, Nashville, TN 37232, United States,Corresponding author at: 1161 21st Ave S, MCN AA1105, Nashville, TN 37232, USA.
| | - Margareta A. Clarke
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, 1161 21st Avenue South, Medical Center North, AA-1105, Nashville, TN 37232-2310, United States
| | - Kristin P. O'Grady
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, 1161 21st Avenue South, Medical Center North, AA-1105, Nashville, TN 37232-2310, United States,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Medical Center North, 1161 21st Ave. South, Nashville, TN 37232, United States,Department of Biomedical Engineering, Vanderbilt University, 2301 Vanderbilt Place, PMB 351826, Nashville, TN 37235-1826, United States
| | - Kurt G. Schilling
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, 1161 21st Avenue South, Medical Center North, AA-1105, Nashville, TN 37232-2310, United States,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Medical Center North, 1161 21st Ave. South, Nashville, TN 37232, United States
| | - Seth A. Smith
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, 1161 21st Avenue South, Medical Center North, AA-1105, Nashville, TN 37232-2310, United States,Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Medical Center North, 1161 21st Ave. South, Nashville, TN 37232, United States,Department of Biomedical Engineering, Vanderbilt University, 2301 Vanderbilt Place, PMB 351826, Nashville, TN 37235-1826, United States
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Glasser MF, Coalson TS, Harms MP, Xu J, Baum GL, Autio JA, Auerbach EJ, Greve DN, Yacoub E, Van Essen DC, Bock NA, Hayashi T. Empirical transmit field bias correction of T1w/T2w myelin maps. Neuroimage 2022; 258:119360. [PMID: 35697132 PMCID: PMC9483036 DOI: 10.1016/j.neuroimage.2022.119360] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 06/01/2022] [Accepted: 06/04/2022] [Indexed: 12/30/2022] Open
Abstract
T1-weighted divided by T2-weighted (T1w/T2w) myelin maps were initially developed for neuroanatomical analyses such as identifying cortical areas, but they are increasingly used in statistical comparisons across individuals and groups with other variables of interest. Existing T1w/T2w myelin maps contain radiofrequency transmit field (B1+) biases, which may be correlated with these variables of interest, leading to potentially spurious results. Here we propose two empirical methods for correcting these transmit field biases using either explicit measures of the transmit field or alternatively a 'pseudo-transmit' approach that is highly correlated with the transmit field at 3T. We find that the resulting corrected T1w/T2w myelin maps are both better neuroanatomical measures (e.g., for use in cross-species comparisons), and more appropriate for statistical comparisons of relative T1w/T2w differences across individuals and groups (e.g., sex, age, or body-mass-index) within a consistently acquired study at 3T. We recommend that investigators who use the T1w/T2w approach for mapping cortical myelin use these B1+ transmit field corrected myelin maps going forward.
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Affiliation(s)
| | | | - Michael P Harms
- Psychiatry, Washington University Medical School, St. Louis, MO, United States
| | - Junqian Xu
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States; Departments of Radiology and Psychiatry, Baylor College of Medicine, Houston, TX, United States
| | - Graham L Baum
- Department of Psychology, Harvard University, Cambridge, MA, United States
| | - Joonas A Autio
- RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Edward J Auerbach
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | - Douglas N Greve
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Essa Yacoub
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States
| | | | - Nicholas A Bock
- Department of Psychology, Neuroscience and Behaviour, McMaster University, Hamilton, ON, Canada
| | - Takuya Hayashi
- RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
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Iwatani J, Ishida T, Donishi T, Ukai S, Shinosaki K, Terada M, Kaneoke Y. Use of T1-weighted/T2-weighted magnetic resonance ratio images to elucidate changes in the schizophrenic brain. Brain Behav 2015; 5:e00399. [PMID: 26516617 PMCID: PMC4614056 DOI: 10.1002/brb3.399] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 07/27/2015] [Accepted: 08/23/2015] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION One leading hypothesis suggests that schizophrenia (SZ) is a neurodevelopmental disorder caused by genetic defects in association with environmental risk factors that affect synapse and myelin formation. Recent magnetic resonance imaging (MRI) studies of SZ brain showed both gray matter (GM) reduction and white matter (WM) fractional anisotropy reduction. In this study, we used T1-weighted (T1w)/T2-weighted (T2w) MRI ratio images, which increase myelin-related signal contrast and reduce receiver-coil bias. METHODS We measured T1w/T2w ratio image signal intensity in 29 patients with SZ and 33 healthy controls (HCs), and then compared them against bias-corrected T1w images. RESULTS Mean T1w/T2w ratio signal intensity values across all SZ GM and WM voxels were significantly lower than those for the HC values (analysis of covariance with age, gender, handedness, and premorbid intelligence quotient as nuisance covariates). SZ mean WM T1w/T2w ratio values were related to Global Assessment of Functioning (GAF) scores and were inversely related to the positive psychotic symptoms of the Positive and Negative Syndrome Scale. Voxel-based analysis revealed significantly lower T1w/T2w ratio image signal intensity values in the right ventral putamen in SZ GM. T1w image intensities did not differ between the SZ and HC groups. CONCLUSIONS T1-weighted/T2-weighted ratio imaging increased the detectability of SZ pathological changes. Reduced SZ brain signal intensity is likely due to diminished myelin content; therefore, mapping myelin-related SZ brain changes using T1w/T2w ratio images may be useful for studies of SZ brain abnormalities.
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Affiliation(s)
- Jun Iwatani
- Department of Neuropsychiatry Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
| | - Takuya Ishida
- Department of Neuropsychiatry Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan ; Department of System Neurophysiology Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
| | - Tomohiro Donishi
- Department of System Neurophysiology Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
| | - Satoshi Ukai
- Department of Neuropsychiatry Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
| | - Kazuhiro Shinosaki
- Department of Neuropsychiatry Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
| | - Masaki Terada
- Wakayama-Minami Radiology Clinic 870-2 Kimiidera Wakayama 641-0012 Japan
| | - Yoshiki Kaneoke
- Department of System Neurophysiology Graduate School of Wakayama Medical University 811-1 Kimiidera Wakayama 641-8509 Japan
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