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Kampaite A, Gustafsson R, York EN, Foley P, MacDougall NJJ, Bastin ME, Chandran S, Waldman AD, Meijboom R. Brain connectivity changes underlying depression and fatigue in relapsing-remitting multiple sclerosis: A systematic review. PLoS One 2024; 19:e0299634. [PMID: 38551913 PMCID: PMC10980255 DOI: 10.1371/journal.pone.0299634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 02/13/2024] [Indexed: 04/01/2024] Open
Abstract
Multiple Sclerosis (MS) is an autoimmune disease affecting the central nervous system, characterised by neuroinflammation and neurodegeneration. Fatigue and depression are common, debilitating, and intertwined symptoms in people with relapsing-remitting MS (pwRRMS). An increased understanding of brain changes and mechanisms underlying fatigue and depression in RRMS could lead to more effective interventions and enhancement of quality of life. To elucidate the relationship between depression and fatigue and brain connectivity in pwRRMS we conducted a systematic review. Searched databases were PubMed, Web-of-Science and Scopus. Inclusion criteria were: studied participants with RRMS (n ≥ 20; ≥ 18 years old) and differentiated between MS subtypes; published between 2001-01-01 and 2023-01-18; used fatigue and depression assessments validated for MS; included brain structural, functional magnetic resonance imaging (fMRI) or diffusion MRI (dMRI). Sixty studies met the criteria: 18 dMRI (15 fatigue, 5 depression) and 22 fMRI (20 fatigue, 5 depression) studies. The literature was heterogeneous; half of studies reported no correlation between brain connectivity measures and fatigue or depression. Positive findings showed that abnormal cortico-limbic structural and functional connectivity was associated with depression. Fatigue was linked to connectivity measures in cortico-thalamic-basal-ganglial networks. Additionally, both depression and fatigue were related to altered cingulum structural connectivity, and functional connectivity involving thalamus, cerebellum, frontal lobe, ventral tegmental area, striatum, default mode and attention networks, and supramarginal, precentral, and postcentral gyri. Qualitative analysis suggests structural and functional connectivity changes, possibly due to axonal and/or myelin loss, in the cortico-thalamic-basal-ganglial and cortico-limbic network may underlie fatigue and depression in pwRRMS, respectively, but the overall results were inconclusive, possibly explained by heterogeneity and limited number of studies. This highlights the need for further studies including advanced MRI to detect more subtle brain changes in association with depression and fatigue. Future studies using optimised imaging protocols and validated depression and fatigue measures are required to clarify the substrates underlying these symptoms in pwRRMS.
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Affiliation(s)
- Agniete Kampaite
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, Edinburgh Imaging Facility, University of Edinburgh, Edinburgh, United Kingdom
| | - Rebecka Gustafsson
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Elizabeth N. York
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, Edinburgh Imaging Facility, University of Edinburgh, Edinburgh, United Kingdom
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter Foley
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
| | - Niall J. J. MacDougall
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
- Department of Neurology, Institute of Neurological Sciences, Queen Elizabeth University Hospital, Glasgow, United Kingdom
| | - Mark E. Bastin
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, Edinburgh Imaging Facility, University of Edinburgh, Edinburgh, United Kingdom
| | - Siddharthan Chandran
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Adam D. Waldman
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, Edinburgh Imaging Facility, University of Edinburgh, Edinburgh, United Kingdom
| | - Rozanna Meijboom
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Edinburgh Imaging, Edinburgh Imaging Facility, University of Edinburgh, Edinburgh, United Kingdom
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Grayev A. Functional Anatomy of the Spinal Cord. Radiol Clin North Am 2024; 62:263-272. [PMID: 38272619 DOI: 10.1016/j.rcl.2023.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Localization of lesions in the spinal cord requires knowledge of the functional anatomy of gray and white matter tracts. Using decussation points for white matter tracts can help determine lesion level. Pathologies can affect gray and white matter tracts in distinct ways and pattern recognition can help narrow down the differential diagnosis.
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Affiliation(s)
- Allison Grayev
- Department of Radiology, University of Wisconsin School of Medicine and Public Health, E1/318, 600 Highland Avenue, Madison, WI 53792-3252, USA.
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Talbott JF, Shah V, Ye AQ. Diffusion Imaging of the Spinal Cord: Clinical Applications. Radiol Clin North Am 2024; 62:273-285. [PMID: 38272620 DOI: 10.1016/j.rcl.2023.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Spinal cord pathologic condition often presents as a neurologic emergency where timely and accurate diagnosis is critical to expedite appropriate treatment and minimize severe morbidity and even mortality. MR imaging is the gold standard imaging technique for diagnosing patients with suspected spinal cord pathologic condition. This review will focus on the basic principles of diffusion imaging and how spinal anatomy presents technical challenges to its application. Both the promises and shortcomings of spinal diffusion imaging will then be explored in the context of several clinical spinal cord pathologies for which diffusion has been evaluated.
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Affiliation(s)
- Jason F Talbott
- Department of Radiology and Biomedical Imaging, Zuckerberg San Francisco General Hospital and Trauma Center, 1001 Potrero Avenue, Room 1X57, San Francisco, CA 94110, USA; Brain and Spinal Injury Center, Zuckerberg San Francisco General Hospital.
| | - Vinil Shah
- Department of Radiology and Biomedical Imaging, Neuroradiology Division, University of California San Francisco, 505 Parnassus Avenue, #M-391, San Francisco, CA 94143, USA
| | - Allen Q Ye
- Department of Radiology and Biomedical Imaging, Zuckerberg San Francisco General Hospital and Trauma Center, 1001 Potrero Avenue, Room 1X57, San Francisco, CA 94110, USA; Department of Radiology and Biomedical Imaging, Neuroradiology Division, University of California San Francisco, 505 Parnassus Avenue, #M-391, San Francisco, CA 94143, USA
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Xu H, Zhou J, Ling C, Xu Y, Tang Z, Cai Y, Li J, Hu Z, Qiu Y, Zhu Z, Liu Z. Potential impairment of spinal cord around the apical vertebral level in hyperkyphotic patients: findings from diffusion tensor imaging. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2024; 33:1256-1264. [PMID: 38340177 DOI: 10.1007/s00586-024-08144-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/31/2023] [Accepted: 01/13/2024] [Indexed: 02/12/2024]
Abstract
PURPOSE To evaluate the neuronal metrics/microstructure of the spinal cord around apical region in patients with hyperkyphosis using diffusion tensor imaging (DTI). METHODS Thirty-seven patients with hyperkyphosis aged 45.5 ± 19.6 years old who underwent 3.0 T magnetic resonance imaging (MRI) examination with DTI sequence were prospectively enrolled from July 2022 to July 2023. Patients were divided into three groups according to spinal cord/ cerebrospinal fluid (CSF) architecture on sagittal-T2 MRI of the thoracic apex (the axial spinal cord classification): Group A-circular cord with visible CSF, Group B-circular cord without visible CSF at apical dorsal, and Group C-spinal cord deformed without intervening CSF. The fractional anisotropy (FA) values acquired from DTI were compared among different groups. Correlations between DTI parameters and global kyphosis (GK)/sagittal deformity angular ratio (sagittal DAR) were evaluated using Pearson correlation coefficients. RESULTS In all patients, FA values were significantly lower at apical level as compared with those at one level above or below the apex (0.548 ± 0.070 vs. 0.627 ± 0.056 versus 0.624 ± 0.039, P < 0.001). At the apical level, FA values were significantly lower in Group C than those in Group B (0.501 ± 0.052 vs. 0.598 ± 0.061, P < 0.001) and Group A (0.501 ± 0.052 vs. 0.597 ± 0.019, P < 0.001). Moreover, FA values were significantly lower in symptomatic group than those in non-symptomatic group (0.498 ± 0.049 v. 0.578 ± 0.065, P < 0.001). Pearson correlation analysis showed that GK (r2 = 0.3945, P < 0.001) and sagittal DAR (r2 = 0.3079, P < 0.001) were significantly correlation with FA values at apical level. CONCLUSION In patients with hyperkyphosis, the FA of spinal cord at apical level was associated with the neuronal metrics/microstructure of the spinal cord. Furthermore, the DTI parameter of FA at apical level was associated with GK and sagittal DAR. LEVEL OF EVIDENCE: 4
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Affiliation(s)
- Hui Xu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Jin Zhou
- Department of Radiology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Chen Ling
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Yanjie Xu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Ziyang Tang
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Yinqi Cai
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Jie Li
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Zongshan Hu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yong Qiu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Zezhang Zhu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Zhen Liu
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.
- Division of Spine Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China.
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Porcine Model of the Growing Spinal Cord-Changes in Diffusion Tensor Imaging Parameters. Animals (Basel) 2023; 13:ani13040565. [PMID: 36830353 PMCID: PMC9951717 DOI: 10.3390/ani13040565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/29/2023] [Accepted: 01/31/2023] [Indexed: 02/08/2023] Open
Abstract
Diffusion tensor imaging (DTI) is an advanced magnetic resonance imaging (MRI) technique that has promising applications for the objective assessment of the microstructure of the spinal cord. This study aimed to verify the parameters obtained using DTI change during the growth process. We also wanted to identify if the DTI values change on the course of the spinal cord. The model organism was a healthy growing porcine spinal cord (19 pigs, Polish White, weight 24-120 kg, mean 48 kg, median 48 kg, age 2.5-11 months, mean 5 months, median 5.5 months). DTI parameters were measured in three weight groups: up to 29 kg (five pigs), 30-59 kg (six pigs), and from 60 kg up (eight pigs). DTI was performed with a 1.5 Tesla magnetic resonance scanner (Philips, Ingenia). Image post-processing was done using the Fiber Track package (Philips Ingenia workstation) by manually drawing the regions of interest (nine ROIs). The measurements were recorded for three sections: the cervical, thoracolumbar and lumbar segments of the spinal cord at the C4/C5, Th13/L1, and L4/L5 vertebrae levels. In each case, one segment was measured cranially and one caudally from the above-mentioned places. The values of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were obtained for each ROIs and compared. It is shown that there is a correlation between age, weight gain, and change in FA and ADC parameters. Moreover, it is noted that, with increasing weight and age, the FA parameter increases and ADC decreases, whereas the FA and ADC measurement values did not significantly change between the three sections of the spinal cord. These findings could be useful in determining the reference values for the undamaged spinal cords of animals and growing humans.
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Schilling KG, Fadnavis S, Batson J, Visagie M, Combes AJE, By S, McKnight CD, Bagnato F, Garyfallidis E, Landman BA, Smith SA, O'Grady KP. Denoising of diffusion MRI in the cervical spinal cord - effects of denoising strategy and acquisition on intra-cord contrast, signal modeling, and feature conspicuity. Neuroimage 2023; 266:119826. [PMID: 36543265 PMCID: PMC9843739 DOI: 10.1016/j.neuroimage.2022.119826] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 11/02/2022] [Accepted: 12/17/2022] [Indexed: 12/23/2022] Open
Abstract
Quantitative diffusion MRI (dMRI) is a promising technique for evaluating the spinal cord in health and disease. However, low signal-to-noise ratio (SNR) can impede interpretation and quantification of these images. The purpose of this study is to evaluate several dMRI denoising approaches on their ability to improve the quality, reliability, and accuracy of quantitative diffusion MRI of the spinal cord. We evaluate three denoising approaches (Non-Local Means, Marchenko-Pastur PCA, and a newly proposed Patch2Self algorithm) and conduct five experiments to validate the denoising performance on clinical-quality and commonly-acquired dMRI acquisitions: 1) a phantom experiment to assess denoising error and bias; 2) a multi-vendor, multi-acquisition open experiment for both qualitative and quantitative evaluation of noise residuals; 3) a bootstrapping experiment to estimate uncertainty of parametric maps; 4) an assessment of spinal cord lesion conspicuity in a multiple sclerosis group; and 5) an evaluation of denoising for advanced parametric multi-compartment modeling. We find that all methods improve signal-to-noise ratio and conspicuity of MS lesions in individual diffusion weighted images (DWIs), but MPPCA and Patch2Self excel at improving the quality and intra-cord contrast of diffusion weighted images - removing signal fluctuations due to thermal noise while improving precision of estimation of diffusion parameters even with very few DWIs (i.e., 16-32) typical of clinical acquisitions. These denoising approaches hold promise for facilitating reliable diffusion observations and measurements in the spinal cord to investigate biological and pathological processes.
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Affiliation(s)
- Kurt G Schilling
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States.
| | - Shreyas Fadnavis
- Department of Intelligent Systems Engineering, Indiana University Bloomington, Bloomington, IN, United States
| | - Joshua Batson
- The Public Health Company, California, United States
| | - Mereze Visagie
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Anna J E Combes
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Samantha By
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
| | - Colin D McKnight
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Francesca Bagnato
- Neuroimaging Unit, Neuroimmunology Division, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Neurology, VA Hospital, TN Valley Healthcare System, Nashville, TN, United States
| | - Eleftherios Garyfallidis
- Department of Intelligent Systems Engineering, Indiana University Bloomington, Bloomington, IN, United States
| | - Bennett A Landman
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, United States
| | - Seth A Smith
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States
| | - Kristin P O'Grady
- Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, United States; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States.
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Mesbah S, Herrity A, Ugiliweneza B, Angeli C, Gerasimenko Y, Boakye M, Harkema S. Neuroanatomical mapping of the lumbosacral spinal cord in individuals with chronic spinal cord injury. Brain Commun 2022; 5:fcac330. [PMID: 36632181 PMCID: PMC9825531 DOI: 10.1093/braincomms/fcac330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 09/27/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
With emerging applications of spinal cord electrical stimulation in restoring autonomic and motor function after spinal cord injury, understanding the neuroanatomical substrates of the human spinal cord after spinal cord injury using neuroimaging techniques can play a critical role in optimizing the outcomes of these stimulation-based interventions. In this study, we have introduced a neuroimaging acquisition and analysis protocol of the spinal cord in order to identify: (i) spinal cord levels at the lumbosacral enlargement using nerve root tracing; (ii) variability in the neuroanatomical characteristics of the spinal cord among individuals; (iii) location of the epidural stimulation paddle electrode and contacts with respect to the spinal cord levels at lumbosacral enlargement; and (iv) the links between the anatomical levels of stimulation and the corresponding neurophysiological motor responses. Twelve individuals with chronic, motor complete spinal cord injury implanted with a spinal cord epidural stimulator were included in the study (age: 34 ± 10.9 years, sex: 10 males, 2 females, time since injury: 8.2 ± 9.9 years, American Spinal Injury Association Impairment Scale: 6 A, 6 B). High-resolution MRI scans of the spinal cord were recorded pre-implant. An analysis of neuroanatomical substrates indicates that the length of the spinal column and spinal cord, location of the conus tip and the relationship between the spinal cord levels and vertebral levels, particularly at the lumbosacral enlargement, are variable across individuals. There is no statistically significant correlation between the length of the spinal column and the length of the spinal cord. The percentage of volumetric coverage of the lumbosacral spinal cord by the epidural stimulation paddle electrode ranges from 33.4 to 90.4% across participants. The location of the spinal cord levels with respect to the electrode contacts varies across individuals and impacts the recruitment patterns of neurophysiological responses. Finally, MRI-based spinal cord modelling can be used as a guide for the prediction and preplanning of optimum epidural stimulation paddle placement prior to the implant surgery to ensure maximizing functional outcomes. These findings highlight the crucial role that the neuroanatomical characteristics of the spinal cord specific to each individual play in achieving maximum functional benefits with spinal cord electrical stimulation.
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Affiliation(s)
- Samineh Mesbah
- Correspondence to: Samineh Mesbah, PhD 220 Abraham Flexner, Louisville, KY 40202, USA E-mail:
| | - April Herrity
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA,Department of Neurological Surgery, University of Louisville, Louisville, KY 40202, USA
| | - Beatrice Ugiliweneza
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA,Department of Neurological Surgery, University of Louisville, Louisville, KY 40202, USA,Department of Health Management and Systems Science, University of Louisville, Louisville, KY 40202, USA
| | - Claudia Angeli
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA,Department of Bioengineering, University of Louisville, Louisville, KY 40292, USA,Frazier Rehabilitation Institute, University of Louisville Health, Louisville, KY 40202, USA
| | - Yury Gerasimenko
- Department of Physiology and Biophysics, University of Louisville, Louisville, KY 40202, USA,Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg 199034, Russia
| | - Maxwell Boakye
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA,Department of Neurological Surgery, University of Louisville, Louisville, KY 40202, USA
| | - Susan Harkema
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA,Department of Neurological Surgery, University of Louisville, Louisville, KY 40202, USA,Frazier Rehabilitation Institute, University of Louisville Health, Louisville, KY 40202, USA
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Lee SY, Schmit BD, Kurpad SN, Budde MD. Acute Magnetic Resonance Imaging Predictors of Chronic Motor Function and Tissue Sparing in Rat Cervical Spinal Cord Injury. J Neurotrauma 2022; 39:1727-1740. [PMID: 35708112 PMCID: PMC9734017 DOI: 10.1089/neu.2022.0034] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Predicting functional outcomes from spinal cord injury (SCI) at the acute setting is important for patient management. This work investigated the relationship of early magnetic resonance imaging (MRI) biomarkers in a rat model of cervical contusion SCI with long-term functional outcome and tissue sparing. Forty rats with contusion injury at C5 at either the spinal cord midline (bilateral) or over the lateral cord (unilateral) were examined using in vivo multi-modal quantitative MRI at 1 day post-injury. The extent of T2-weighted hyperintensity reflecting edema was greater in the bilateral model compared with the unilateral injury. Diffusion tensor imaging (DTI) exhibited microscopic damage in similar regions of the cord as reductions in fractional anisotropy (FA) and mean diffusivity (MD), but DTI parameter maps were also confounded by the presence of vasogenic edema that locally increased FA and MD. In comparison, filtered diffusion-weighted imaging (fDWI) more clearly delineated the location of acute axonal damage without effects of vasogenic edema. Pairwise correlation analysis revealed that 28-day motor functional outcomes were most strongly associated with the extent of edema (R = -0.69). Principal component analysis identified close associations of motor functional score with tissue sparing, the extent of edema, lesion area, and injury type (unilateral or bilateral). Among the diffusion MRI parameters, lesion areas measured with fDWI had the strongest association with functional outcome (R = -0.41). Voxelwise correlation analysis identified a locus of white matter damage associated with function in the dorsal white matter, although this was likely driven by variance across the two injury patterns (unilateral and bilateral injury). Nonetheless, correlation with motor function within the damaged region found in the voxelwise analysis outperformed morphological lesion area measurement as a predictor of chronic function. Collectively, this study characterized anatomical and diffusion MRI signatures of acute SCI at cervical spine and their association with chronic functional outcomes and histological results.
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Affiliation(s)
- Seung-Yi Lee
- Neuroscience Doctoral Program, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Biophysics Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Brian D. Schmit
- Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Shekar N. Kurpad
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Matthew D. Budde
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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9
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Park GS, Kim TU, Lee SJ, Hyun JK, Kim SY. Quantitative Analysis in Cervical Spinal Cord Injury Patients Using Diffusion Tensor Imaging and Tractography. Ann Rehabil Med 2022; 46:172-184. [PMID: 36070999 PMCID: PMC9452286 DOI: 10.5535/arm.22053] [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: 05/10/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Objective To investigate the clinical usefulness of diffusion tensor imaging (DTI) and tractography in the prediction of outcomes after traumatic cervical spinal cord injury (SCI) and to assess whether the predictability is different between DTI and tractography administered before and after surgery. Methods Sixty-one subjects with traumatic cervical SCI were randomly assigned to preop or postop groups and received DTI accordingly. Among the patients who had DTI before surgery, we assigned 10 patients who had received repeated DTI examinations at 8 weeks after injury to the follow-up group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained from DTI, and imaginary fiber and crossing fiber numbers were calculated from the tractography. Neurological status and functional status were assessed at 4 and 8 weeks after SCI. Results The neurologic and functional statuses of both groups improved after 4 weeks. Out of the initial 61 patients who were enrolled in the study, the failure rate of DTI image analysis was significantly higher in the postop group (n=17, 41.5%) than in the preop group (n=6, 20%). The FA values and fiber numbers in the preop group tended to be higher than those in the postop group, whereas ADC values were lower in the preop group. When comparing the tractographic findings in the follow-up group, imaginary fiber numbers at the C6 and C7 levels and crossing fiber numbers from the C3 to C6 levels were significantly decreased after surgery. Several DTI and tractographic parameters (especially the ADC value at the C4 level and imaginary fiber numbers at the C6 level) showed significant correlations with neurologic and functional statuses in both the preop and postop groups. These findings were most prominent when DTI and physical examination were simultaneously performed. Conclusion Preoperative DTI and tractography demonstrated better FA and ADC values with lower interpretation failure rates than those obtained after surgery, whereas postoperative data significantly reflected the patient’s clinical state at the time of evaluation. Therefore, DTI and tractography could be useful in predicting clinical outcomes after traumatic cervical SCI and should be interpreted separately before and after spine surgery.
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Imaging of Thoracolumbar Spine Traumas. Eur J Radiol 2022; 154:110343. [DOI: 10.1016/j.ejrad.2022.110343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 11/15/2022]
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Zhu F, Wang Y, Kong X, Liu Y, Zeng L, Jing X, Yao S, Chen K, Yang L, Guo X. Assessment of acute traumatic cervical spinal cord injury using conventional magnetic resonance imaging in combination with diffusion tensor imaging-tractography: a retrospective comparative study. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2022; 31:1700-1709. [PMID: 35639157 DOI: 10.1007/s00586-022-07207-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 02/10/2022] [Accepted: 04/01/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE The application of conventional magnetic resonance imaging (MRI) in combination with diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) to diagnose acute traumatic cervical SCI has not been studied. This study explores the role of MRI with DTI-DTT in the diagnosis of acute traumatic cervical spinal cord injury (SCI). METHODS Thirty patients with acute traumatic cervical SCI underwent conventional MRI and DTI-DTT. Conventional MRI was used to detect the intramedullary lesion length (IMLL) and intramedullary hemorrhage length (IMHL). DTI was used to detect the spinal cord's fractional anisotropy (FA) and apparent diffusion coefficient value, and DTT detected the imaginary white matter fiber volume and the connection rates of fiber tractography (CRFT). Patients' neurological outcome was determined using the American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades. RESULTS Patients were divided into group A (without AIS grade conversion) and group B (with AIS grade conversion). The IMLL and IMHL of group A were significantly higher than those of group B. The FA and CRFT of group A were significantly lower than those of group B. The final AIS grade was negatively correlated with the IMLL and IMHL, and positively correlated with the FA and CRFT. According to imaging features based on conventional MRI and DTI-DTT, we propose a novel classification and diagnostic procedure. CONCLUSIONS The combination of conventional MRI with DTI-DTT is a valid diagnostic approach for SCI. Lower IMLL and IMHL, and higher FA value and CRFT are linked to better neurological outcomes.
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Affiliation(s)
- Fengzhao Zhu
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China.,Department of Orthopaedics, Xinqiao Hospital, Army Military University, Chongqing, China
| | - Yulong Wang
- Department of Orthopedics, Wuhan No. 1 Hospital, Wuhan Integrated TCM & Western Medicine Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiangchuang Kong
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuan Liu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lian Zeng
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China
| | - Xirui Jing
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China
| | - Sheng Yao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China
| | - Kaifang Chen
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China
| | - Lian Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaodong Guo
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1227 Jiefang Avenue, Wuhan, China.
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Omar MKM, Abd Allah AEKH, Maghrabi MG, Mohamed MZ. The value of quantitative diffusion tensor imaging indices of spinal cord disorders. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2021. [DOI: 10.1186/s43055-021-00596-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Different lesions affecting the spinal cord can lead to myelopathy. Diffusion tensor imaging (DTI) is widely used to predict the degree of spinal cord microstructure affection and to assess axonal integrity and diffusion directionality. We hypothesized that not all DTI parameters have the same affection with different spinal cord pathologies. The purpose of this study is to assess the value of the quantitative diffusion tensor imaging indices in different spinal cord lesions.
Results
There is highly statistically significant difference of the fractional anisotropy (FA), relative anisotropy (RA), volume ratio (VR) and secondary eigenvector values (E2 and E3) between various studied cord lesions and control levels. There is no statistically significant difference of the apparent diffusion coefficient (ADC) and the primary eigenvector value (E1) (ANOVA test). The ROC curve analysis showed the higher sensitivity and accuracy were ‘88% and 62.5%, respectively,’ with FA cutoff value about 0.380.
Conclusion
The resulted quantitative DTI indices ‘fractional anisotropy, relative anisotropy, volume ratio and secondary eigenvalues’ work as a numerical in vivo marker of overall tissue injury in different pathologies affecting the spinal cord.
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Antkowiak L, Rogalska M, Stogowski P, Anuszkiewicz K, Mandera M. Clinical Application of Diffusion Tensor Imaging in Chiari Malformation Type I- Advances and Perspectives. A Systematic Review. World Neurosurg 2021; 152:124-136. [PMID: 34147690 DOI: 10.1016/j.wneu.2021.06.052] [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: 05/04/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Diffusion tensor imaging (DTI) application in Chiari malformation type I (CMI) is still poorly defined. This study aimed to systematically review the literature and propose perspectives toward the clinical application of DTI in CMI. METHODS PubMed and Embase were searched for English-language articles published until October 20, 2020. Clinical studies and case series, evaluating fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), or radial diffusivity values in patients with CMI, were included. RESULTS Eight articles were included. Lower FA values were found at the syrinx level, which decreased with syrinx extent and intensity of symptoms, reflecting myelopathy severity. Decreased AD and MD in the middle cerebellar peduncles in symptomatic patients with CMI might explain the presence of cerebellar signs. Increased FA in various supratentorial structures positively correlated with pain severity. Worse performance in neuropsychological tests correlated with decreased FA, increased MD, and radial diffusivity, reflecting axonal degeneration. Postoperative FA decrease in the brainstem compression area reflects successful decompression. A positive correlation was found between the extent of tonsillar ectopia and increased FA, MD, and AD values, which could act as an early indicator of acute brainstem compression. CONCLUSIONS DTI might provide a valuable insight into the neurobiological foundation of symptomatic CMI presentation. The severity of white matter injury evident on DTI could serve as a reliable predictor of postoperative outcomes, therefore facilitating selection of appropriate surgical candidates. Postinterventional DTI reassessment might enable differentiation between unsuccessful surgical technique and irreversible myelopathy. The extent of tonsillar ectopia reflects the severity of microstructural brainstem injury.
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Affiliation(s)
- Lukasz Antkowiak
- Department of Pediatric Neurosurgery, Medical University of Silesia, Katowice, Poland.
| | - Marta Rogalska
- Faculty of Medicine, Medical University of Warsaw, Warsaw, Poland
| | - Piotr Stogowski
- Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | | | - Marek Mandera
- Department of Pediatric Neurosurgery, Medical University of Silesia, Katowice, Poland
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Mesbah S, Ball T, Angeli C, Rejc E, Dietz N, Ugiliweneza B, Harkema S, Boakye M. Predictors of volitional motor recovery with epidural stimulation in individuals with chronic spinal cord injury. Brain 2021; 144:420-433. [PMID: 33367527 DOI: 10.1093/brain/awaa423] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/25/2020] [Accepted: 09/30/2020] [Indexed: 12/25/2022] Open
Abstract
Spinal cord epidural stimulation (scES) has enabled volitional lower extremity movements in individuals with chronic and clinically motor complete spinal cord injury and no clinically detectable brain influence. The aim of this study was to understand whether the individuals' neuroanatomical characteristics or positioning of the scES electrode were important factors influencing the extent of initial recovery of lower limb voluntary movements in those with clinically motor complete paralysis. We hypothesized that there would be significant correlations between the number of joints moved during attempts with scES prior to any training interventions and the amount of cervical cord atrophy above the injury, length of post-traumatic myelomalacia and the amount of volume coverage of lumbosacral enlargement by the stimulation electrode array. The clinical and imaging records of 20 individuals with chronic and clinically motor complete spinal cord injury who underwent scES implantation were reviewed and analysed using MRI and X-ray integration, image segmentation and spinal cord volumetric reconstruction techniques. All individuals that participated in the scES study (n = 20) achieved, to some extent, lower extremity voluntary movements post scES implant and prior to any locomotor, voluntary movement or cardiovascular training. The correlation results showed that neither the cross-section area of spinal cord at C3 (n = 19, r = 0.33, P = 0.16) nor the length of severe myelomalacia (n = 18, r = -0.02, P = 0.93) correlated significantly with volitional lower limb movement ability. However, there was a significant, moderate correlation (n = 20, r = 0.59, P = 0.006) between the estimated percentage of the lumbosacral enlargement coverage by the paddle electrode as well as the position of the paddle relative to the maximal lumbosacral enlargement and the conus tip (n = 20, r = 0.50, P = 0.026) with the number of joints moved volitionally. These results suggest that greater coverage of the lumbosacral enlargement by scES may improve motor recovery prior to any training, possibly because of direct modulatory effects on the spinal networks that control lower extremity movements indicating the significant role of motor control at the level of the spinal cord.
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Affiliation(s)
- Samineh Mesbah
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA
| | - Tyler Ball
- Department of Neurosurgery, University of Louisville, Louisville, KY, USA
| | - Claudia Angeli
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.,Department of Bioengineering, University of Louisville, Louisville, KY, USA.,Frazier Rehab Institute, University of Louisville Health, Louisville, KY, USA
| | - Enrico Rejc
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.,Department of Neurosurgery, University of Louisville, Louisville, KY, USA
| | - Nicholas Dietz
- Department of Neurosurgery, University of Louisville, Louisville, KY, USA
| | - Beatrice Ugiliweneza
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.,Department of Neurosurgery, University of Louisville, Louisville, KY, USA
| | - Susan Harkema
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.,Department of Neurosurgery, University of Louisville, Louisville, KY, USA.,Frazier Rehab Institute, University of Louisville Health, Louisville, KY, USA
| | - Maxwell Boakye
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, USA.,Department of Neurosurgery, University of Louisville, Louisville, KY, USA
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15
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Tu J, Vargas Castillo J, Das A, Diwan AD. Degenerative Cervical Myelopathy: Insights into Its Pathobiology and Molecular Mechanisms. J Clin Med 2021; 10:jcm10061214. [PMID: 33804008 PMCID: PMC8001572 DOI: 10.3390/jcm10061214] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/07/2021] [Accepted: 03/09/2021] [Indexed: 12/12/2022] Open
Abstract
Degenerative cervical myelopathy (DCM), earlier referred to as cervical spondylotic myelopathy (CSM), is the most common and serious neurological disorder in the elderly population caused by chronic progressive compression or irritation of the spinal cord in the neck. The clinical features of DCM include localised neck pain and functional impairment of motor function in the arms, fingers and hands. If left untreated, this can lead to significant and permanent nerve damage including paralysis and death. Despite recent advancements in understanding the DCM pathology, prognosis remains poor and little is known about the molecular mechanisms underlying its pathogenesis. Moreover, there is scant evidence for the best treatment suitable for DCM patients. Decompressive surgery remains the most effective long-term treatment for this pathology, although the decision of when to perform such a procedure remains challenging. Given the fact that the aged population in the world is continuously increasing, DCM is posing a formidable challenge that needs urgent attention. Here, in this comprehensive review, we discuss the current knowledge of DCM pathology, including epidemiology, diagnosis, natural history, pathophysiology, risk factors, molecular features and treatment options. In addition to describing different scoring and classification systems used by clinicians in diagnosing DCM, we also highlight how advanced imaging techniques are being used to study the disease process. Last but not the least, we discuss several molecular underpinnings of DCM aetiology, including the cells involved and the pathways and molecules that are hallmarks of this disease.
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Affiliation(s)
- Ji Tu
- Spine Labs, St. George and Sutherland Clinical School, University of New South Wales, Kogarah, NSW 2217, Australia; (J.T.); (A.D.D.)
| | | | - Abhirup Das
- Spine Labs, St. George and Sutherland Clinical School, University of New South Wales, Kogarah, NSW 2217, Australia; (J.T.); (A.D.D.)
- Spine Service, St. George Hospital, Kogarah, NSW 2217, Australia;
- Correspondence:
| | - Ashish D. Diwan
- Spine Labs, St. George and Sutherland Clinical School, University of New South Wales, Kogarah, NSW 2217, Australia; (J.T.); (A.D.D.)
- Spine Service, St. George Hospital, Kogarah, NSW 2217, Australia;
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16
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Lee SY, Meyer BP, Kurpad SN, Budde MD. Diffusion-prepared fast spin echo for artifact-free spinal cord imaging. Magn Reson Med 2021; 86:984-994. [PMID: 33720450 DOI: 10.1002/mrm.28751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/07/2021] [Accepted: 02/05/2021] [Indexed: 12/13/2022]
Abstract
PURPOSE Diffusion MRI provides unique contrast important for the detection and examination of pathophysiology after acute neurologic insults, including spinal cord injury. Diffusion weighted imaging of the rodent spinal cord has typically been evaluated with axial EPI readout. However, Diffusion weighted imaging is prone to motion artifacts, whereas EPI is prone to susceptibility artifacts. In the context of acute spinal cord injury, diffusion filtering has previously been shown to improve detection of injury by minimizing the confounding effects of edema. We propose a diffusion-preparation module combined with a rapid acquisition with relaxation enhancement readout to minimize artifacts for sagittal imaging. METHODS Sprague-Dawley rats with cervical contusion spinal cord injury were scanned at 9.4 Tesla. The sequence optimization included the evaluation of motion-compensated encoding diffusion gradients, gating strategy, and different spinal cord-specific diffusion-weighting schemes. RESULTS A diffusion-prepared rapid acquisition with relaxation enhancement achieved high-quality images free from susceptibility artifacts with both second-order motion-compensated encoding and gating necessary for reduction of motion artifacts. Axial diffusivity obtained from the filtered diffusion-encoding scheme had greater lesion-to-healthy tissue contrast (52%) compared to the similar metric from DTI (25%). CONCLUSION This work demonstrated the feasibility of high-quality diffusion sagittal imaging in the rodent cervical cord with diffusion-prepared relaxation enhancement. The sequence and results are expected to improve injury detection and evaluation in acute spinal cord injury.
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Affiliation(s)
- Seung-Yi Lee
- Neuroscience Doctoral Program, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Briana P Meyer
- Neuroscience Doctoral Program, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Shekar N Kurpad
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Matthew D Budde
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA.,Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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17
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Zhu F, Zeng L, Gui S, Liu Y, Wang Y, Cao X, Lin H, Yang L, Kong X, Guo X. The Role of Diffusion Tensor Imaging and Diffusion Tensor Tractography in the Assessment of Acute Traumatic Thoracolumbar Spinal Cord Injury. World Neurosurg 2021; 150:e23-e30. [PMID: 33561552 DOI: 10.1016/j.wneu.2021.01.146] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND This study explored diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) to assess the prognosis of thoracolumbar spinal cord injury (SCI). METHODS Twenty patients with acute traumatic thoracolumbar complete SCI (T1-L1, American Spinal Injury Association Impairment Scale [AIS] grade A) underwent conventional magnetic resonance imaging and DTI examinations. DTI measured the fractional anisotropy (FA) and apparent diffusion coefficient adjacent to the lesion epicenter. DTT was used to detect the white matter fiber morphology and measure the imaginary white matter fiber volume and connection rates of fiber tractography (CRFT). The patients' neurological functions were evaluated by the AIS grades. RESULTS At the final-follow-up, among the 20 patients with AIS grade A, 15 maintained the AIS grade (group A), and 5 patients showed improvement of AIS grade (group B). Group A's mean FA value was significantly lower than that of group B, whereas the mean apparent diffusion coefficient value among the 2 groups showed no significant difference. The white matter fibers of most patients in group A were completely ruptured (11/15), but the white matter fibers of all patients in group B were retained in different number (5/5). The mean CRFT of group B was significantly higher than that of group A (P < 0.05). The improvement of AIS grade was slightly positively correlated with FA values and highly positively correlated with CRFT. CONCLUSIONS The prognosis of complete thoracolumbar SCI may be related to the FA value and the CRFT. The application of DTI and DTT may optimize the diagnosis of thoracolumbar SCI.
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Affiliation(s)
- Fengzhao Zhu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lian Zeng
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Shan Gui
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yuan Liu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yulong Wang
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaojian Cao
- Department of Spine Surgery, Jiangsu Province Hospital and Nanjing Medical University First Affiliated Hospital, Nanjing, Jiangsu, China
| | - Haodong Lin
- Department of Orthopaedics, Shanghai First People's Hospital, Shanghai Jiaotong University First People's Hospital, Shanghai, China
| | - Lian Yang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiangchuang Kong
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaodong Guo
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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18
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Mossa-Basha M, Peterson DJ, Hippe DS, Vranic JE, Hofstetter C, Reyes M, Bombardier C, Jarvik JG. Segmented quantitative diffusion tensor imaging evaluation of acute traumatic cervical spinal cord injury. Br J Radiol 2021; 94:20201000. [PMID: 33180553 DOI: 10.1259/bjr.20201000] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES To evaluate segmented diffusion tensor imaging (DTI) white matter tract fractional anisotropy (FA) and mean diffusivity (MD) values in acute cervical spinal cord injury (CSCI). METHODS 15 patients with acute CSCI and 12 control subjects were prospectively recruited and underwent axial DTI as part of the spine trauma MRI. Datasets were put through a semi-automated probabilistic segmentation algorithm that analyzed white matter, motor and sensory tracts. FA and MD values were calculated for white matter, sensory (spinal lemniscal) and motor tracts (ventral/lateral corticospinal) at the level of clinical injury, levels remote from injury and in normal controls. RESULTS There were significant differences in FA between the level of injury and controls for total white matter (0.65 ± .09 vs 0.68 ± .07; p = .044), motor tracts (0.64 ± .07 vs 0.7 ± .09; p = .006), and combined motor/sensory tracts (0.63 ± .09 vs 0.69 ± .08; p = .022). In addition, there were significant FA differences between the level of injury and one level caudal to the injury for combined motor tracts (0.64 ± .07 vs 0.69 ± .05; p = .002) and combined motor/sensory tracts (0.63 ± .09 vs 0.7 ± .07; p = .011). There were no significant differences for MD between the level of injury and one level caudal to the injury or normal controls. CONCLUSION Abnormalities in DTI metrics of DTI-segmented white matter tracts were detected at the neurological level of injury relative to normal controls and levels remote from the injury site, confirming its value in CSCI assessment. ADVANCES IN KNOWLEDGE Segmented DTI analysis can help identify microstructural spinal cord abnormalities in the setting of traumatic cervical spinal cord injury.
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Affiliation(s)
| | | | - Daniel S Hippe
- Department of Radiology, University of Washington, Seattle, WA, USA
| | - Justin E Vranic
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | | | - Maria Reyes
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Charles Bombardier
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Jeffrey G Jarvik
- Department of Radiology, University of Washington, Seattle, WA, USA.,Department of Neurosurgery, University of Washington, Seattle, WA, USA.,Department of Health Services, University of Washington, Seattle, WA, USA
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19
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Johnson PJ, Miller AD, Cheetham J, Demeter EA, Luh WM, Loftus JP, Stephan SL, Dewey CW, Barry EF. In vivo detection of microstructural spinal cord lesions in dogs with degenerative myelopathy using diffusion tensor imaging. J Vet Intern Med 2020; 35:352-362. [PMID: 33350517 PMCID: PMC7848345 DOI: 10.1111/jvim.16014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 11/30/2022] Open
Abstract
Background Degenerative myelopathy (DM) in dogs is a progressive neurodegenerative condition that causes white matter spinal cord lesions. These lesions are undetectable on standard magnetic resonance imaging (MRI), limiting diagnosis and monitoring of the disease. Spinal cord lesions cause disruption to the structural integrity of the axons causing water diffusion to become more random and less anisotropic. These changes are detectable by the technique of diffusion tensor imaging (DTI) which is highly sensitive to diffusion alterations secondary to white matter lesion development. Objective Perform spinal DTI on cohorts of dogs with and without DM to identify if lesions caused by DM will cause a detectable alteration in spinal cord diffusivity that correlates with neurological status. Animals Thirteen dogs with DM and 13 aged‐matched controls. Methods All animals underwent MRI with DTI of the entire spine. Diffusivity parameters fractional anisotropy (FA) and mean diffusivity (MD) were measured at each vertebral level and statistically compared between groups. Results Dogs with DM had significant decreases in FA within the regions of the spinal cord that had high expected lesion load. Decreases in FA were most significant in dogs with severe forms of the disease and correlated with neurological grade. Conclusions and Clinical Importance Findings suggest that FA has the potential to be a biomarker for spinal cord lesion development in DM and could play an important role in improving diagnosis and monitoring of this condition.
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Affiliation(s)
- Philippa J Johnson
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Andrew D Miller
- Department of Biomedical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Jonathan Cheetham
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Elena A Demeter
- Department of Biomedical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Wen-Ming Luh
- National Institute on Aging, National Institutes of Health, Bethesda, Maryland, USA
| | - John P Loftus
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Sarah L Stephan
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Curtis W Dewey
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Erica F Barry
- Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
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20
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Tong T, Lu H, Zong J, Lv Q, Chu X. Chemotherapy-related cognitive impairment in patients with breast cancer based on MRS and DTI analysis. Breast Cancer 2020; 27:893-902. [PMID: 32301096 DOI: 10.1007/s12282-020-01094-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 03/26/2020] [Indexed: 12/20/2022]
Abstract
The purpose of this study is to investigate chemotherapy-related cognitive impairment (CRCI) in breast cancer patients, analyze absolute concentration and structural changes of metabolites in different brain regions by multimodal neuroimaging technology, and explore correlation between them. Breast cancer patients with chemotherapy treatment group (Ctx+, N = 24) and control group without treatment (Ctx-, N = 20) underwent neuropsychological tests, multivoxel magnetic resonance spectroscopy (MRS), and diffusion tensor imaging (DTI) before and after chemotherapy. Regions of interest (ROls) in magnetic resonance scan include bilateral posterior cingulate gyrus (PCG), bilateral dorsal thalamus (DT), bilateral lenticular nucleus (LN), bilateral posterior horn of the lateral ventricle paratrigonal white matter (PWM). In MRS, absolute concentrations of N-acetylaspartate (NAA), myo-inositol (MI), choline-containing compounds (Cho), total creatine (tCr), glutamine + glutamate (Glx) were quantified using LC Model and SAGE software. In DTI, we used fractional anisotropy (FA) and mean diffusivity (MD) to reflect white matter integrity. In Ctx+ patients, scores of functional assessment of cancer treatment cognition test (FACT-Cog), perceived cognitive impairments (PCI), impact of perceived impairments on quality of life (QOL), perceived cognitive abilities (PCA), auditory-verbal learning test (AVLT) recognition and clock drawing test (CDT) were lower than those before chemotherapy (p < 0.05). In MRS, Ctx+ patients had significantly lower NAA values in bilateral PCG, DT, respectively. The concentrations of tCr were observed to decline in bilateral PCG and right DT. Glx values decreased in right DT. Cho values decreased significantly in bilateral DT. In DTI, Ctx+ patients had lower FA values in bilateral PCG compared with patients before chemotherapy. Among imaging metrics and cognitive scores, positive correlations were observed between changes in AVLT recognition scores and changes in NAA values in bilateral PCG (left PCG: r = 0.470, p < 0.01; right PCG: r = 0.500, p < 0.01). Positive correlations were also found between changes in AVLT recognition and changes in FA values in bilateral PCG (left PCG: r = 0.513, p < 0.01; right PCG: r = 0.563, p < 0.01). Chemotherapy can lead to a decrease in memory function, accompanied by changes in brain metabolite concentration and white matter integrity in some parts of brain.
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Affiliation(s)
- Taishan Tong
- Department of Psychology and Psychiatry, Affiliated Hospital of Jiangnan University, 200 Huihe Road, Wuxi, 214000, Jiangsu, China
| | - Heng Lu
- Department of Psychology and Psychiatry, Affiliated Hospital of Jiangnan University, 200 Huihe Road, Wuxi, 214000, Jiangsu, China
| | - Jian Zong
- Department of Magnetic Resonance Imaging, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Qing Lv
- Department of Breast Surgery, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Xing Chu
- Department of Psychology and Psychiatry, Affiliated Hospital of Jiangnan University, 200 Huihe Road, Wuxi, 214000, Jiangsu, China.
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Noguerol TM, Barousse R, Amrhein TJ, Royuela-del-Val J, Montesinos P, Luna A. Optimizing Diffusion-Tensor Imaging Acquisition for Spinal Cord Assessment: Physical Basis and Technical Adjustments. Radiographics 2020; 40:403-427. [DOI: 10.1148/rg.2020190058] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Teodoro Martín Noguerol
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
| | - Rafael Barousse
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
| | - Timothy J. Amrhein
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
| | - Javier Royuela-del-Val
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
| | - Paula Montesinos
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
| | - Antonio Luna
- From the MRI Section, Department of Radiology, SERCOSA, Health Time, Carmelo Torres 2, 23007, Jaén, Spain (T.M.N., A.L.); Peripheral Nerve and Plexus Department, Centro Rossi, Buenos Aires, Argentina (R.B.); Department of Radiology, Duke University Medical Center, Durham, N.C. (T.J.A.); RESSALTA, Health Time, Córdoba, Spain (J.R.d.V.); and Philips Iberia, Madrid, Spain (P.M.)
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22
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Wilkins N, Skinner NP, Motovylyak A, Schmit BD, Kurpad S, Budde MD. Evolution of Magnetic Resonance Imaging as Predictors and Correlates of Functional Outcome after Spinal Cord Contusion Injury in the Rat. J Neurotrauma 2020; 37:889-898. [PMID: 31830856 DOI: 10.1089/neu.2019.6731] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Clinical methods for determining the severity of traumatic spinal cord injury (SCI) and long-term functional outcome in the acute setting are limited in their prognostic accuracy because of the heterogeneity of injury and dynamic injury progression. The aim of this study was to evaluate the time course and sensitivity of advanced magnetic resonance imaging (MRI) methods to neurological function after SCI in a rat contusion model. Rats received a graded contusion injury at T10 using a weight-drop apparatus. MRI consisted of morphological measures from T2-weighted imaging, quantitative T2 imaging, and diffusion-weighted imaging (DWI) at 1, 30, and 90 days post-injury (dpi). The derived metrics were compared with neurological function assessed using weekly Basso, Beattie, and Bresnahan (BBB) locomotor scoring and return of reflexive micturition function. At the acute time point (1 dpi), diffusion metrics sensitive to axonal injury at the injury epicenter had the strongest correlation with time-matched BBB scores and best predicted 90-dpi BBB scores. At 30 dpi, axonal water fraction derived from DWI and T2 values were both correlated with time-matched locomotor scores. At the chronic time point (90 dpi), cross-sectional area was most closely correlated to BBB. Overall, the results demonstrate differential sensitivity of MRI metrics at different time points after injury, but the metrics follow the expected pathology of acute axonal injury followed by continued degeneration and finally a terminal level of atrophy. Specificity of DWI in the acute setting may make it impactful as a prognostic tool while T2 imaging provided the most information about injury severity in chronic injury.
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Affiliation(s)
- Natasha Wilkins
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Nathan P Skinner
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin.,Medical Scientist Training Program, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Alice Motovylyak
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Brian D Schmit
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Shekar Kurpad
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Matthew D Budde
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
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23
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Mossa-Basha M, Gerszten PC, Myrehaug S, Mayr NA, Yuh WT, Jabehdar Maralani P, Sahgal A, Lo SS. Spinal metastasis: diagnosis, management and follow-up. Br J Radiol 2019; 92:20190211. [PMID: 31322920 DOI: 10.1259/bjr.20190211] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Spine metastatic disease is an increasingly common occurrence in cancer patients due to improved patient survival. Close proximity of the bony spinal column to the spinal cord limits many conventional treatments for metastatic disease. In the past decade, we have witnessed dramatic advancements in therapies, with improvements in surgical techniques and recent adoption of spine stereotactic radiotherapy techniques leading to improved patient outcomes. Multidisciplinary approaches to patient evaluation, treatment and follow-up are essential. Imaging plays an ever increasing role in disease detection, pre-treatment planning and assessment of patient outcomes. It is important for the radiologist to be familiar with imaging algorithms, best practices for surgery and/or radiotherapy and imaging findings in the post-treatment period that may indicate disease recurrence. In this review, we present a multidisciplinary discussion of spine metastases, with specific focus on pre-treatment imaging, planning, current treatment approaches, and post-treatment assessment.
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Affiliation(s)
| | - Peter C Gerszten
- Department of Neurosurgery, University of Pittsburgh, Pittsburgh, PA
| | - Sten Myrehaug
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto, ON Canada
| | - Nina A Mayr
- Department of Radiation Oncology, University of Washington, Seattle, WA
| | - William Tc Yuh
- Department of Radiology, University of Washington, Seattle, WA
| | - Pejman Jabehdar Maralani
- Department of Medical Imaging, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Arjun Sahgal
- Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto, ON Canada
| | - Simon S Lo
- Department of Radiation Oncology, University of Washington, Seattle, WA
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24
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Frostell A, Mattsson P, Svensson M. Guiding Device for Precision Grafting of Peripheral Nerves in Complete Thoracic Spinal Cord Injury: Design and Sizing for Clinical Trial. Front Neurol 2018; 9:356. [PMID: 29872421 PMCID: PMC5972322 DOI: 10.3389/fneur.2018.00356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 05/01/2018] [Indexed: 01/08/2023] Open
Abstract
Background In an effort to translate preclinical success in achieving spinal cord regeneration through peripheral nerve grafts, this study details the design and sizing of a guiding device for precision grafting of peripheral nerves for use in a clinical trial in complete (AIS-A) thoracic spinal cord injury (SCI). The device’s design and sizing are compared to a simulation of human spinal cord sizes based on the best available data. Methods Spinal cord segmental sizes were generated by computer simulation based on data from a meta-analysis recently published by our group. Thoracic segments T2–T12 were plotted, and seven elliptical shapes were positioned across the center of the distribution of sizes. Geometrical measures of error-of-fit were calculated. CAD modeling was used to create cranial and caudal interfaces for the human spinal cord, aiming to guide descending white matter tracts to gray matter at the caudal end of the device and ascending white matter tracts to gray matter at the cranial end of the device. The interfaces were compared qualitatively to the simulated spinal cord sizes and gray-to-white matter delineations. Results The mean error-of-fit comparing simulated spinal cord segments T2–T12 to the best elliptical shape was 0.41 and 0.36 mm, and the 95th percentile was found at 1.3 and 0.98 mm for transverse and anteroposterior diameter, respectively. A guiding device design was reached for capturing the majority of corticospinal axons at the cranial end of the device and guiding them obliquely to gray matter at the caudal end of the device. Based on qualitative comparison, the vast majority of spinal cord sizes generated indicate an excellent fit to the device’s interfaces. Conclusion A set of SCI guiding devices of seven sizes can cover the variability of human thoracic spinal cord segments T2–T12 with an acceptable error-of-fit for the elliptical shape as well as guiding channels. The computational framework developed can be used with other medical technologies involving the human spinal cord where exact sizes and positioning are of importance.
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Affiliation(s)
- Arvid Frostell
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Per Mattsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Breast, Endocrine and Sarcoma Tumors, Karolinska University Hospital, Stockholm, Sweden
| | - Mikael Svensson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Neurosurgery, Karolinska University Hospital, Stockholm, Sweden
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