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Kaļva K, Zdanovskis N, Šneidere K, Kostiks A, Karelis G, Platkājis A, Stepens A. Whole Brain and Corpus Callosum Fractional Anisotropy Differences in Patients with Cognitive Impairment. Diagnostics (Basel) 2023; 13:3679. [PMID: 38132263 PMCID: PMC10742911 DOI: 10.3390/diagnostics13243679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/20/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023] Open
Abstract
Diffusion tensor imaging (DTI) is an MRI analysis method that could help assess cognitive impairment (CI) in the ageing population more accurately. In this research, we evaluated fractional anisotropy (FA) of whole brain (WB) and corpus callosum (CC) in patients with normal cognition (NC), mild cognitive impairment (MCI), and moderate/severe cognitive impairment (SCI). In total, 41 participants were included in a cross-sectional study and divided into groups based on Montreal Cognitive Assessment (MoCA) scores (NC group, nine participants, MCI group, sixteen participants, and SCI group, sixteen participants). All participants underwent an MRI examination that included a DTI sequence. FA values between the groups were assessed by analysing FA value and age normative percentile. We did not find statistically significant differences between the groups when analysing CC FA values. Both approaches showed statistically significant differences in WB FA values between the MCI-SCI and MCI-NC groups, where the MCI group participants showed the highest mean FA and highest mean FA normative percentile results in WB.
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Affiliation(s)
- Kalvis Kaļva
- Department of Radiology, Riga Stradins University, LV-1007 Riga, Latvia; (K.K.)
- Department of Radiology, Riga East Clinical University Hospital, LV-1038 Riga, Latvia
| | - Nauris Zdanovskis
- Department of Radiology, Riga Stradins University, LV-1007 Riga, Latvia; (K.K.)
- Department of Radiology, Riga East Clinical University Hospital, LV-1038 Riga, Latvia
- Military Medicine Research and Study Centre, Riga Stradins University, LV-1007 Riga, Latvia
| | - Kristīne Šneidere
- Military Medicine Research and Study Centre, Riga Stradins University, LV-1007 Riga, Latvia
- Department of Health Psychology and Paedagogy, Riga Stradins University, LV-1007 Riga, Latvia
| | - Andrejs Kostiks
- Department of Neurology and Neurosurgery, Riga East University Hospital, LV-1038 Riga, Latvia; (A.K.)
| | - Guntis Karelis
- Department of Neurology and Neurosurgery, Riga East University Hospital, LV-1038 Riga, Latvia; (A.K.)
- Department of Infectology, Riga Stradins University, LV-1007 Riga, Latvia
| | - Ardis Platkājis
- Department of Radiology, Riga Stradins University, LV-1007 Riga, Latvia; (K.K.)
- Department of Radiology, Riga East Clinical University Hospital, LV-1038 Riga, Latvia
| | - Ainārs Stepens
- Military Medicine Research and Study Centre, Riga Stradins University, LV-1007 Riga, Latvia
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Chen J, Chung S, Li T, Fieremans E, Novikov DS, Wang Y, Lui YW. Identifying relevant diffusion MRI microstructure biomarkers relating to exposure to repeated head impacts in contact sport athletes. Neuroradiol J 2023; 36:693-701. [PMID: 37212469 PMCID: PMC10649530 DOI: 10.1177/19714009231177396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023] Open
Abstract
PURPOSE Repeated head impacts (RHI) without concussion may cause long-term sequelae. A growing array of diffusion MRI metrics exist, both empiric and modeled and it is hard to know which are potentially important biomarkers. Common conventional statistical methods fail to consider interactions between metrics and rely on group-level comparisons. This study uses a classification pipeline as a means towards identifying important diffusion metrics associated with subconcussive RHI. METHODS 36 collegiate contact sport athletes and 45 non-contact sport controls from FITBIR CARE were included. Regional/whole brain WM statistics were computed from 7 diffusion metrics. Wrapper-based feature selection was applied to 5 classifiers representing a range of learning capacities. Best 2 classifiers were interpreted to identify the most RHI-related diffusion metrics. RESULTS Mean diffusivity (MD) and mean kurtosis (MK) are found to be the most important metrics for discriminating between athletes with and without RHI exposure history. Regional features outperformed global statistics. Linear approaches outperformed non-linear approaches with good generalizability (test AUC 0.80-0.81). CONCLUSION Feature selection and classification identifies diffusion metrics that characterize subconcussive RHI. Linear classifiers yield the best performance and mean diffusion, tissue microstructure complexity, and radial extra-axonal compartment diffusion (MD, MK, De,⊥) are found to be the most influential metrics. This work provides proof of concept that applying such approach to small, multidimensional dataset can be successful given attention to optimizing learning capacity without overfitting and serves an example of methods that lead to better understanding of the myriad of diffusion metrics as they relate to injury and disease.
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Affiliation(s)
- Junbo Chen
- Department of Electrical and Computer Engineering, New York University Tandon School of Engineering, Brooklyn, NY, USA
| | - Sohae Chung
- Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Tianhao Li
- Department of Electrical and Computer Engineering, New York University Tandon School of Engineering, Brooklyn, NY, USA
| | - Els Fieremans
- Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Dmitry S Novikov
- Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Yao Wang
- Department of Electrical and Computer Engineering, New York University Tandon School of Engineering, Brooklyn, NY, USA
| | - Yvonne W Lui
- Center for Advanced Imaging Innovation and Research (CAI2R), Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York, NY, USA
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Ferreira PF, Banerjee A, Scott AD, Khalique Z, Yang G, Rajakulasingam R, Dwornik M, De Silva R, Pennell DJ, Firmin DN, Nielles‐Vallespin S. Accelerating Cardiac Diffusion Tensor Imaging With a U-Net Based Model: Toward Single Breath-Hold. J Magn Reson Imaging 2022; 56:1691-1704. [PMID: 35460138 PMCID: PMC9790699 DOI: 10.1002/jmri.28199] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/04/2022] [Accepted: 04/04/2022] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND In vivo cardiac diffusion tensor imaging (cDTI) characterizes myocardial microstructure. Despite its potential clinical impact, considerable technical challenges exist due to the inherent low signal-to-noise ratio. PURPOSE To reduce scan time toward one breath-hold by reconstructing diffusion tensors for in vivo cDTI with a fitting-free deep learning approach. STUDY TYPE Retrospective. POPULATION A total of 197 healthy controls, 547 cardiac patients. FIELD STRENGTH/SEQUENCE A 3 T, diffusion-weighted stimulated echo acquisition mode single-shot echo-planar imaging sequence. ASSESSMENT A U-Net was trained to reconstruct the diffusion tensor elements of the reference results from reduced datasets that could be acquired in 5, 3 or 1 breath-hold(s) (BH) per slice. Fractional anisotropy (FA), mean diffusivity (MD), helix angle (HA), and sheetlet angle (E2A) were calculated and compared to the same measures when using a conventional linear-least-square (LLS) tensor fit with the same reduced datasets. A conventional LLS tensor fit with all available data (12 ± 2.0 [mean ± sd] breath-holds) was used as the reference baseline. STATISTICAL TESTS Wilcoxon signed rank/rank sum and Kruskal-Wallis tests. Statistical significance threshold was set at P = 0.05. Intersubject measures are quoted as median [interquartile range]. RESULTS For global mean or median results, both the LLS and U-Net methods with reduced datasets present a bias for some of the results. For both LLS and U-Net, there is a small but significant difference from the reference results except for LLS: MD 5BH (P = 0.38) and MD 3BH (P = 0.09). When considering direct pixel-wise errors the U-Net model outperformed significantly the LLS tensor fit for reduced datasets that can be acquired in three or just one breath-hold for all parameters. DATA CONCLUSION Diffusion tensor prediction with a trained U-Net is a promising approach to minimize the number of breath-holds needed in clinical cDTI studies. EVIDENCE LEVEL 4 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Pedro F. Ferreira
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | | | - Andrew D. Scott
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Zohya Khalique
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Guang Yang
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Ramyah Rajakulasingam
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Maria Dwornik
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Ranil De Silva
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Dudley J. Pennell
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - David N. Firmin
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
| | - Sonia Nielles‐Vallespin
- Cardiovascular Magnetic Resonance UnitRoyal Brompton HospitalLondonUK
- National Heart and Lung InstituteImperial CollegeLondonUK
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Association between attention-deficit/hyperactivity disorder symptom severity and white matter integrity moderated by in-scanner head motion. Transl Psychiatry 2022; 12:434. [PMID: 36202807 PMCID: PMC9537185 DOI: 10.1038/s41398-022-02117-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 08/11/2022] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a common and debilitating neurodevelopmental disorder associated with various negative life impacts. The manifestation of ADHD is very heterogeneous, and previous investigations on neuroanatomical alterations in ADHD have yielded inconsistent results. We investigated the mediating effect of in-scanner head motion and ADHD hyperactivity severity on motion-corrected fractional anisotropy (FA) using diffusion tensor imaging in the currently largest sample (n = 739) of medication-naïve children and adolescents (age range 5-22 years). We used automated tractography to examine whole-brain and mean FA of the tracts most frequently reported in ADHD; corpus callosum forceps major and forceps minor, left and right superior-longitudinal fasciculus, and left and right corticospinal tract (CST). Associations between FA and hyperactivity severity appeared when in-scanner head motion was not accounted for as mediator. However, causal mediation analysis revealed that these effects are fully mediated through in-scanner head motion for whole-brain FA, the corpus callosum forceps minor, and left superior-longitudinal fasciculus. Direct effect of hyperactivity severity on FA was only found for the left CST. This study illustrates the crucial role of in-scanner head motion in the identification of white matter integrity alterations in ADHD and shows how neglecting irremediable motion artifacts causes spurious findings. When the mediating effect of in-scanner head motion on FA is accounted for, an association between hyperactivity severity and FA is only present for the left CST; this may play a crucial role in the manifestation of hyperactivity and impulsivity symptoms in ADHD.
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Führes T, Saake M, Lorenz J, Seuss H, Stemmer A, Benkert T, Uder M, Laun FB. Reduction of the cardiac pulsation artifact and improvement of lesion conspicuity in flow‐compensated diffusion images in the liver—A quantitative evaluation of postprocessing algorithms. Magn Reson Med 2022; 89:423-439. [PMID: 36089798 DOI: 10.1002/mrm.29427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 08/05/2022] [Accepted: 08/08/2022] [Indexed: 11/10/2022]
Abstract
PURPOSE To enhance image quality of flow-compensated diffusion-weighted liver MRI data by increasing the lesion conspicuity and reducing the cardiac pulsation artifact using postprocessing algorithms. METHODS Diffusion-weighted image data of 40 patients with liver lesions had been acquired at 1.5 T. These data were postprocessed with 5 different algorithms (weighted averaging, p-mean, percentile, outlier exclusion, and exception set). Four image properties of the postprocessed data were evaluated for optimizing the algorithm parameters. These properties were the lesion to tissue contrast-to-noise ratio (CNR), the reduction of the cardiac pulsation artifact, the data consistency, and the vessel darkness. They were combined into a total quality score ( Q total , $$ {Q}_{\mathrm{total}}, $$ set to 1 for the trace-weighted reference image), which was used to rate the image quality objectively. RESULTS The weighted averaging algorithm performed best according to the total quality score ( Q total = 1.111 ± 0.067 $$ {Q}_{\mathrm{total}}=1.111\pm 0.067 $$ ). The further ranking was outlier exclusion algorithm ( Q total = 1.086 ± 0.061 $$ {Q}_{\mathrm{total}}=1.086\pm 0.061 $$ ), p-mean algorithm ( Q total = 1.045 ± 0.049 $$ {Q}_{\mathrm{total}}=1.045\pm 0.049 $$ ), percentile algorithm ( Q total = 1.012 ± 0.049 $$ {Q}_{\mathrm{total}}=1.012\pm 0.049 $$ ), and exception set algorithm ( Q total = 0.957 ± 0.027 $$ {Q}_{\mathrm{total}}=0.957\pm 0.027 $$ ). All optimized algorithms except for the exception set algorithm corrected the pulsation artifact and increased the lesion CNR. Changes in Q total $$ {Q}_{\mathrm{total}} $$ were significant for all optimized algorithms except for the percentile algorithm. Liver ADC was significantly reduced (except for the exception set algorithm), particularly in the left lobe. CONCLUSION Postprocessing algorithms should be used for flow-compensated liver DWI. The proposed weighted averaging algorithm seems to be suited best to increase the image quality of artifact-corrupted flow-compensated diffusion-weighted liver data.
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Affiliation(s)
- Tobit Führes
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Marc Saake
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Jennifer Lorenz
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Hannes Seuss
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
- Abteilung für Radiologie Klinikum Forchheim – Fränkische Schweiz Forchheim Germany
| | - Alto Stemmer
- MR Application Predevelopment Siemens Healthcare GmbH Erlangen Germany
| | - Thomas Benkert
- MR Application Predevelopment Siemens Healthcare GmbH Erlangen Germany
| | - Michael Uder
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
| | - Frederik Bernd Laun
- Institute of Radiology, University Hospital Erlangen Friedrich‐Alexander‐Universität Erlangen‐Nürnberg (FAU) Erlangen Germany
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Tröndle M, Popov T, Dziemian S, Langer N. Decomposing the role of alpha oscillations during brain maturation. eLife 2022; 11:77571. [PMID: 36006005 PMCID: PMC9410707 DOI: 10.7554/elife.77571] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 07/26/2022] [Indexed: 12/21/2022] Open
Abstract
Childhood and adolescence are critical stages of the human lifespan, in which fundamental neural reorganizational processes take place. A substantial body of literature investigated accompanying neurophysiological changes, focusing on the most dominant feature of the human EEG signal: the alpha oscillation. Recent developments in EEG signal-processing show that conventional measures of alpha power are confounded by various factors and need to be decomposed into periodic and aperiodic components, which represent distinct underlying brain mechanisms. It is therefore unclear how each part of the signal changes during brain maturation. Using multivariate Bayesian generalized linear models, we examined aperiodic and periodic parameters of alpha activity in the largest openly available pediatric dataset (N=2529, age 5-22 years) and replicated these findings in a preregistered analysis of an independent validation sample (N=369, age 6-22 years). First, the welldocumented age-related decrease in total alpha power was replicated. However, when controlling for the aperiodic signal component, our findings provided strong evidence for an age-related increase in the aperiodic-adjusted alpha power. As reported in previous studies, also relative alpha power revealed a maturational increase, yet indicating an underestimation of the underlying relationship between periodic alpha power and brain maturation. The aperiodic intercept and slope decreased with increasing age and were highly correlated with total alpha power. Consequently, earlier interpretations on age-related changes of total alpha power need to be reconsidered, as elimination of active synapses rather links to decreases in the aperiodic intercept. Instead, analyses of diffusion tensor imaging data indicate that the maturational increase in aperiodic-adjusted alpha power is related to increased thalamocortical connectivity. Functionally, our results suggest that increased thalamic control of cortical alpha power is linked to improved attentional performance during brain maturation.
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Affiliation(s)
- Marius Tröndle
- Department of Psychology, University of Zurich, Methods of Plasticity Research, Zurich, Switzerland.,University Research Priority Program (URPP) Dynamic of Healthy Aging, Zurich, Switzerland
| | - Tzvetan Popov
- Department of Psychology, University of Zurich, Methods of Plasticity Research, Zurich, Switzerland.,University Research Priority Program (URPP) Dynamic of Healthy Aging, Zurich, Switzerland
| | - Sabine Dziemian
- Department of Psychology, University of Zurich, Methods of Plasticity Research, Zurich, Switzerland.,University Research Priority Program (URPP) Dynamic of Healthy Aging, Zurich, Switzerland
| | - Nicolas Langer
- Department of Psychology, University of Zurich, Methods of Plasticity Research, Zurich, Switzerland.,University Research Priority Program (URPP) Dynamic of Healthy Aging, Zurich, Switzerland.,Neuroscience Center Zurich (ZNZ), University of Zurich & ETH Zurich, Zurich, Switzerland
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Bells S, Longoni G, Berenbaum T, de Medeiros CB, Narayanan S, Banwell BL, Arnold DL, Mabbott DJ, Ann Yeh E. Patterns of white and gray structural abnormality associated with paediatric demyelinating disorders. Neuroimage Clin 2022; 34:103001. [PMID: 35381508 PMCID: PMC8980471 DOI: 10.1016/j.nicl.2022.103001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/21/2022] [Accepted: 03/30/2022] [Indexed: 11/26/2022]
Abstract
A multi-modal approach was used to evaluate the visual pathway from anterior (retina) to posterior (visual cortex) in both paediatric MOGAD and MS patients. MS patients exhibited more widespread white matter abnormalities; MOGAD patients exhibited white matter changes primarily within the optic radiation. The pattern of cortical thinning differed in MS and MOGAD patients. Reduced RNFLT was associated with lower axonal density in MOGAD and tortuosity in MS.
The impact of multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) - associated disorders (MOGAD) on brain structure in youth remains poorly understood. Reductions in cortical mantle thickness on structural MRI and abnormal diffusion-based white matter metrics (e.g., diffusion tensor parameters) have been well documented in MS but not in MOGAD. Characterizing structural abnormalities found in children with these disorders can help clarify the differences and similarities in their impact on neuroanatomy. Importantly, while MS and MOGAD affect the entire CNS, the visual pathway is of particular interest in both groups, as most patients have evidence for clinical or subclinical involvement of the anterior visual pathway. Thus, the visual pathway is of key interest in analyses of structural abnormalities in these disorders and may distinguish MOGAD from MS patients. In this study we collected MRI data on 18 MS patients, 14 MOGAD patients and 26 age- and sex-matched typically developing children (TDC). Full-brain group differences in fixel diffusion measures (fibre-bundle populations) and cortical thickness measures were tested using age and sex as covariates. Visual pathway analysis was performed by extracting mean diffusion measures within lesion free optic radiations, cortical thickness within the visual cortex, and retinal nerve fibre layer (RNFL) and ganglion cell layer thickness measures from optical coherence tomography (OCT). Fixel based analysis (FBA) revealed MS patients have widespread abnormal white matter within the corticospinal tract, inferior longitudinal fasciculus, and optic radiations, while within MOGAD patients, non-lesional impact on white matter was found primarily in the right optic radiation. Cortical thickness measures were reduced predominately in the temporal and parietal lobes in MS patients and in frontal, cingulate and visual cortices in MOGAD patients. Additionally, our findings of associations between reduced RNFLT and axonal density in MOGAD and TORT in MS patients in the optic radiations imply widespread axonal and myelin damage in the visual pathway, respectively. Overall, our approach of combining FBA, cortical thickness and OCT measures has helped evaluate similarities and differences in brain structure in MS and MOGAD patients in comparison to TDC.
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Affiliation(s)
- Sonya Bells
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada; Pediatric Neurology, Spectrum Health Helen Devos Children's Hospital, Grand Rapids, USA; Department of Pediatrics and Human Development, Michigan State University, East Lansing, USA
| | - Giulia Longoni
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada; Department of Neurology, Hospital for Sick Children, Toronto, Canada; Department of Paediatrics, University of Toronto, Toronto, Canada
| | - Tara Berenbaum
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Cynthia B de Medeiros
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada
| | - Sridar Narayanan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Brenda L Banwell
- Division of Child Neurology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, USA
| | - Douglas L Arnold
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Donald J Mabbott
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada; Department of Psychology, University of Toronto, Toronto, Canada
| | - E Ann Yeh
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Canada; Department of Neurology, Hospital for Sick Children, Toronto, Canada; Department of Paediatrics, University of Toronto, Toronto, Canada.
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Chung S, Chen J, Li T, Wang Y, Lui YW. Investigating Brain White Matter in Football Players with and without Concussion Using a Biophysical Model from Multishell Diffusion MRI. AJNR Am J Neuroradiol 2022; 43:823-828. [PMID: 35589140 DOI: 10.3174/ajnr.a7522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 04/04/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE There have been growing concerns around potential risks related to sports-related concussion and contact sport exposure to repetitive head impacts in young athletes. Here we investigate WM microstructural differences between collegiate football players with and without sports-related concussion. MATERIALS AND METHODS The study included 78 collegiate athletes (24 football players with sports-related concussion, 26 football players with repetitive head impacts, and 28 non-contact-sport control athletes), available through the Federal Interagency Traumatic Brain Injury Research registry. Diffusion metrics of diffusion tensor/kurtosis imaging and WM tract integrity were calculated. Tract-Based Spatial Statistics and post hoc ROI analyses were performed to test group differences. RESULTS Significantly increased axial kurtosis in those with sports-related concussion compared with controls was observed diffusely across the whole-brain WM, and some focal areas demonstrated significantly higher mean kurtosis and extra-axonal axial diffusivity in sports-related concussion. The extent of significantly different WM regions decreased across time points and remained present primarily in the corpus callosum. Similar differences in axial kurtosis were found between the repetitive head impact and control groups. Other significant differences were seen at unrestricted return-to-play with lower radial kurtosis and intra-axonal diffusivity in those with sports-related concussion compared with the controls, mainly restricted to the posterior callosum. CONCLUSIONS This study highlights the fact that there are differences in diffusion microstructure measures that are present not only between football players with sports-related injuries and controls, but that there are also measurable differences between football players with repetitive head impacts and controls. This work reinforces previous work showing that the corpus callosum is specifically implicated in sports-related concussion and also suggests this to be true for repetitive head impacts.
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Affiliation(s)
- S Chung
- From the Department of Radiology (S.C., Y.W.L.), Center for Advanced Imaging Innovation and Research .,Department of Radiology (S.C., Y.W.L.), Bernard and Irene Schwartz Center for Biomedical Imaging, New York University Grossman School of Medicine, New York, New York
| | - J Chen
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - T Li
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - Y Wang
- Department of Electrical and Computer Engineering (J.C., T.L., Y.W.), New York University Tandon School of Engineering, Brooklyn, New York
| | - Y W Lui
- From the Department of Radiology (S.C., Y.W.L.), Center for Advanced Imaging Innovation and Research.,Department of Radiology (S.C., Y.W.L.), Bernard and Irene Schwartz Center for Biomedical Imaging, New York University Grossman School of Medicine, New York, New York
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Kornaropoulos EN, Winzeck S, Rumetshofer T, Wikstrom A, Knutsson L, Correia MM, Sundgren PC, Nilsson M. Sensitivity of Diffusion MRI to White Matter Pathology: Influence of Diffusion Protocol, Magnetic Field Strength, and Processing Pipeline in Systemic Lupus Erythematosus. Front Neurol 2022; 13:837385. [PMID: 35557624 PMCID: PMC9087851 DOI: 10.3389/fneur.2022.837385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
There are many ways to acquire and process diffusion MRI (dMRI) data for group studies, but it is unknown which maximizes the sensitivity to white matter (WM) pathology. Inspired by this question, we analyzed data acquired for diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) at 3T (3T-DTI and 3T-DKI) and DTI at 7T in patients with systemic lupus erythematosus (SLE) and healthy controls (HC). Parameter estimates in 72 WM tracts were obtained using TractSeg. The impact on the sensitivity to WM pathology was evaluated for the diffusion protocol, the magnetic field strength, and the processing pipeline. Sensitivity was quantified in terms of Cohen's d for group comparison. Results showed that the choice of diffusion protocol had the largest impact on the effect size. The effect size in fractional anisotropy (FA) across all WM tracts was 0.26 higher when derived by DTI than by DKI and 0.20 higher in 3T compared with 7T. The difference due to the diffusion protocol was larger than the difference due to magnetic field strength for the majority of diffusion parameters. In contrast, the difference between including or excluding different processing steps was near negligible, except for the correction of distortions from eddy currents and motion which had a clearly positive impact. For example, effect sizes increased on average by 0.07 by including motion and eddy correction for FA derived from 3T-DTI. Effect sizes were slightly reduced by the incorporation of denoising and Gibbs-ringing removal (on average by 0.011 and 0.005, respectively). Smoothing prior to diffusion model fitting generally reduced effect sizes. In summary, 3T-DTI in combination with eddy current and motion correction yielded the highest sensitivity to WM pathology in patients with SLE. However, our results also indicated that the 3T-DKI and 7T-DTI protocols used here may be adjusted to increase effect sizes.
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Affiliation(s)
- Evgenios N. Kornaropoulos
- Clinical Sciences, Diagnostic Radiology, Lund University, Lund, Sweden
- Division of Anaesthesia, University of Cambridge, Cambridge, United Kingdom
| | - Stefan Winzeck
- Division of Anaesthesia, University of Cambridge, Cambridge, United Kingdom
- BioMedIA Group, Department of Computing, Imperial College London, London, United Kingdom
| | | | - Anna Wikstrom
- Clinical Sciences, Diagnostic Radiology, Lund University, Lund, Sweden
| | - Linda Knutsson
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, MD, United States
- F.M. Kirby Research Center, Kennedy Krieger Institute, Baltimore, MD, United States
| | - Marta M. Correia
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, United Kingdom
| | - Pia C. Sundgren
- Clinical Sciences, Diagnostic Radiology, Lund University, Lund, Sweden
- Lund University BioImaging Center, Lund University, Lund, Sweden
- Department of Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden
| | - Markus Nilsson
- Clinical Sciences, Diagnostic Radiology, Lund University, Lund, Sweden
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Guo L, Lyu J, Zhang Z, Shi J, Feng Q, Feng Y, Gao M, Zhang X. A Joint Framework for Denoising and Estimating Diffusion Kurtosis Tensors Using Multiple Prior Information. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:308-319. [PMID: 34520348 DOI: 10.1109/tmi.2021.3112515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Diffusion kurtosis imaging (DKI) has been shown to be valuable in a wide range of neuroscientific and clinical applications. However, reliable estimation of DKI tensors is often compromised by noise, especially for the kurtosis tensor (KT). Here, we propose a joint denoising and estimating framework that integrates multiple sources of prior information, including nonlocal structural self-similarity (NSS), local spatial smoothness (LSS), physical relevance (PR) of the DKI model, and noise characteristics of magnitude diffusion MRI (dMRI) images for improved estimation of DKI tensors. The local and nonlocal spatial smoothing constraints are complementary to each other, making the proposed framework highly effective in reducing the noise fluctuations on DKI tensors, especially KT. As an additional refinement, we propose to impose a physically relevant constraint within our joint denoising and estimation framework. We further adopt the first-moment noise-corrected fitting model (M1NCM) to remove the noncentral χ -distribution noise bias. The effectiveness of integrating multiple sources of priors into the joint framework is verified by comparing the proposed M1NCM-NSS-LSS-PR method with various versions of M1NCM-based estimators and two state-of-the-art methods. Results show that the proposed method outperformed the compared methods in simulations and in-vivo dMRI datasets of both spatially stationary and nonstationary noise distributions. The in-vivo experiments also show that the proposed M1NCM-NSS-LSS-PR method was robust to the number of diffusion directions.
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11
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What's New and What's Next in Diffusion MRI Preprocessing. Neuroimage 2021; 249:118830. [PMID: 34965454 PMCID: PMC9379864 DOI: 10.1016/j.neuroimage.2021.118830] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 10/26/2021] [Accepted: 12/15/2021] [Indexed: 02/07/2023] Open
Abstract
Diffusion MRI (dMRI) provides invaluable information for the study of tissue microstructure and brain connectivity, but suffers from a range of imaging artifacts that greatly challenge the analysis of results and their interpretability if not appropriately accounted for. This review will cover dMRI artifacts and preprocessing steps, some of which have not typically been considered in existing pipelines or reviews, or have only gained attention in recent years: brain/skull extraction, B-matrix incompatibilities w.r.t the imaging data, signal drift, Gibbs ringing, noise distribution bias, denoising, between- and within-volumes motion, eddy currents, outliers, susceptibility distortions, EPI Nyquist ghosts, gradient deviations, B1 bias fields, and spatial normalization. The focus will be on “what’s new” since the notable advances prior to and brought by the Human Connectome Project (HCP), as presented in the predecessing issue on “Mapping the Connectome” in 2013. In addition to the development of novel strategies for dMRI preprocessing, exciting progress has been made in the availability of open source tools and reproducible pipelines, databases and simulation tools for the evaluation of preprocessing steps, and automated quality control frameworks, amongst others. Finally, this review will consider practical considerations and our view on “what’s next” in dMRI preprocessing.
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12
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Henriques RN, Jespersen SN, Jones DK, Veraart J. Toward more robust and reproducible diffusion kurtosis imaging. Magn Reson Med 2021; 86:1600-1613. [PMID: 33829542 PMCID: PMC8199974 DOI: 10.1002/mrm.28730] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 01/20/2021] [Accepted: 01/24/2021] [Indexed: 12/21/2022]
Abstract
PURPOSE The general utility of diffusion kurtosis imaging (DKI) is challenged by its poor robustness to imaging artifacts and thermal noise that often lead to implausible kurtosis values. THEORY AND METHODS A robust scalar kurtosis index can be estimated from powder-averaged diffusion-weighted data. We introduce a novel DKI estimator that uses this scalar kurtosis index as a proxy for the mean kurtosis to regularize the fit. RESULTS The regularized DKI estimator improves the robustness and reproducibility of the kurtosis metrics and results in parameter maps with enhanced quality and contrast. CONCLUSION Our novel DKI estimator promotes the wider use of DKI in clinical research and potentially diagnostics by improving the reproducibility and precision of DKI fitting and, as such, enabling enhanced visual, quantitative, and statistical analyses of DKI parameters.
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Affiliation(s)
| | - Sune N. Jespersen
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLabDepartment of Clinical MedicineAarhus UniversityAarhusDenmark
- Department of Physics and AstronomyAarhus UniversityAarhusDenmark
| | - Derek K. Jones
- CUBRICSchool of PsychologyCardiff UniversityCardiffUK
- Mary MacKillop Institute for Health ResearchAustralian Catholic UniversityMelbourneVictoriaAustralia
| | - Jelle Veraart
- Center for Biomedical ImagingNew York University Grossman School of MedicineNew YorkNYUSA
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13
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Van Dyck P, Froeling M, Heusdens CHW, Sijbers J, Ribbens A, Billiet T. Diffusion tensor imaging of the anterior cruciate ligament following primary repair with internal bracing: A longitudinal study. J Orthop Res 2021; 39:1318-1330. [PMID: 32270563 DOI: 10.1002/jor.24684] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 03/17/2020] [Accepted: 03/28/2020] [Indexed: 02/04/2023]
Abstract
Diffusion tensor imaging (DTI) provides information about tissue microstructure and its degree of organization by quantifying water diffusion. We aimed to monitor longitudinal changes in DTI parameters (fractional isotropy, FA; mean diffusivity, MD; axial diffusivity, AD; radial diffusivity, RD) of the anterior cruciate ligament (ACL) following primary repair with internal bracing (IBLA). Fourteen patients undergoing IBLA were enrolled prospectively and scheduled for clinical follow-up, including instrumented laxity testing, and DTI at 3, 6, 12, and 24 months postoperatively. DTI was also performed in seven healthy subjects. Fiber tractography was used for 3D segmentation of the whole ACL volume, from which median DTI parameters were calculated. The posterior cruciate ligament (PCL) served as a control. Longitudinal DTI changes were assessed using a linear mixed model, and repeated measures correlations were calculated between DTI parameters and clinical laxity tests. At follow-up, thirteen patients had a stable knee and one patient sustained an ACL rerupture after 12 months postoperatively. The ACL repair showed a significant decrease of FA within the first 12 months after surgery, followed by stable FA values thereafter, while ACL diffusivities decreased over time returning towards normal values at 24 months postoperatively. For PCL there were no significant DTI changes over time. There was a significant correlation between ACL FA and laxity tests (r = -0.42, P = .017). This study has shown the potential of DTI to longitudinally monitor diffusion changes in the ACL following IBLA. The DTI findings suggest that healing of the ACL repair is incomplete at 24 months postoperatively.
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Affiliation(s)
- Pieter Van Dyck
- Department of Radiology, Antwerp University Hospital and University of Antwerp, Edegem, Belgium
| | - Martijn Froeling
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Jan Sijbers
- Imec-Vision Lab, Department of Physics, University of Antwerp, Wilrijk, Belgium
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14
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Gong T, Tong Q, Li Z, He H, Zhang H, Zhong J. Deep learning-based method for reducing residual motion effects in diffusion parameter estimation. Magn Reson Med 2020; 85:2278-2293. [PMID: 33058279 DOI: 10.1002/mrm.28544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 11/08/2022]
Abstract
PURPOSE Conventional motion-correction techniques for diffusion MRI can introduce motion-level-dependent bias in derived metrics. To address this challenge, a deep learning-based technique was developed to minimize such residual motion effects. METHODS The data-rejection approach was adopted in which motion-corrupted data are discarded before model-fitting. A deep learning-based parameter estimation algorithm, using a hierarchical convolutional neural network (H-CNN), was combined with motion assessment and corrupted volume rejection. The method was designed to overcome the limitations of existing methods of this kind that produce parameter estimations whose quality depends strongly on a proportion of the data discarded. Evaluation experiments were conducted for the estimation of diffusion kurtosis and diffusion-tensor-derived measures at both the individual and group levels. The performance was compared with the robust approach of iteratively reweighted linear least squares (IRLLS) after motion correction with and without outlier replacement. RESULTS Compared with IRLLS, the H-CNN-based technique is minimally sensitive to motion effects. It was tested at severe motion levels when 70% to 90% of the data are rejected and when random motion is present. The technique had a stable performance independent of the numbers and schemes of data rejection. A further test on a data set from children with attention-deficit hyperactivity disorder shows the technique can potentially ameliorate spurious group-level difference caused by head motion. CONCLUSION This method shows great potential for reducing residual motion effects in motion-corrupted diffusion-weighted-imaging data, bringing benefits that include reduced bias in derived metrics in individual scans and reduced motion-level-dependent bias in population studies employing diffusion MRI.
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Affiliation(s)
- Ting Gong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, China.,Department of Computer Science & Centre for Medical Image Computing, University College London, London, UK
| | - Qiqi Tong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, China
| | - Zhiwei Li
- Department of Instrument Science & Technology, Zhejiang University, Hangzhou, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, China
| | - Hui Zhang
- Department of Computer Science & Centre for Medical Image Computing, University College London, London, UK
| | - Jianhui Zhong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, China.,Department of Imaging Sciences, University of Rochester, Rochester, NY, USA
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15
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Zhou Z, Tong Q, Zhang L, Ding Q, Lu H, Jonkman LE, Yao J, He H, Zhu K, Zhong J. Evaluation of the diffusion MRI white matter tract integrity model using myelin histology and Monte-Carlo simulations. Neuroimage 2020; 223:117313. [PMID: 32882384 DOI: 10.1016/j.neuroimage.2020.117313] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 12/13/2022] Open
Abstract
Quantitative evaluation of brain myelination has drawn considerable attention. Conventional diffusion-based magnetic resonance imaging models, including diffusion tensor imaging and diffusion kurtosis imaging (DKI),1 have been used to infer the microstructure and its changes in neurological diseases. White matter tract integrity (WMTI) was proposed as a biophysical model to relate the DKI-derived metrics to the underlying microstructure. Although the model has been validated on ex vivo animal brains, it was not well evaluated with ex vivo human brains. In this study, histological samples (namely corpus callosum) from postmortem human brains have been investigated based on WMTI analyses on a clinical 3T scanner and comparisons with gold standard myelin staining in proteolipid protein and Luxol fast blue. In addition, Monte Carlo simulations were conducted to link changes from ex vivo to in vivo conditions based on the microscale parameters of water diffusivity and permeability. The results show that WMTI metrics, including axonal water fraction AWF, radial extra-axonal diffusivity De⊥, and intra-axonal diffusivity Dawere needed to characterize myelin content alterations. Thus, WMTI model metrics are shown to be promising candidates as sensitive biomarkers of demyelination.
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Affiliation(s)
- Zihan Zhou
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China
| | - Qiqi Tong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China
| | - Lei Zhang
- China Brain Bank and Department of Neurology in Second Affiliated Hospital, Key Laboratory of Medical Neurobiology of Zhejiang Province, and Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Pathology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Qiuping Ding
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China
| | - Hui Lu
- China Brain Bank and Department of Neurology in Second Affiliated Hospital, Key Laboratory of Medical Neurobiology of Zhejiang Province, and Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Laura E Jonkman
- Department of Anatomy and Neurosciences, Amsterdam Neuroscience, Amsterdam UMC, location VUmc, the Netherlands
| | - Junye Yao
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China.
| | - Keqing Zhu
- China Brain Bank and Department of Neurology in Second Affiliated Hospital, Key Laboratory of Medical Neurobiology of Zhejiang Province, and Department of Neurobiology, Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Pathology, Zhejiang University School of Medicine, Hangzhou 310058, China.
| | - Jianhui Zhong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Zhouyiqing Building, Room 314, Yuquan Campus, Hangzhou 310027, China; Department of Imaging Sciences, University of Rochester, United States
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16
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Tong Q, Gong T, He H, Wang Z, Yu W, Zhang J, Zhai L, Cui H, Meng X, Tax CWM, Zhong J. A deep learning-based method for improving reliability of multicenter diffusion kurtosis imaging with varied acquisition protocols. Magn Reson Imaging 2020; 73:31-44. [PMID: 32822818 DOI: 10.1016/j.mri.2020.08.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 07/13/2020] [Accepted: 08/14/2020] [Indexed: 01/02/2023]
Abstract
Multicenter magnetic resonance imaging is gaining more popularity in large-sample projects. Since both varying hardware and software across different centers cause unavoidable data heterogeneity across centers, its impact on reliability in study outcomes has also drawn much attention recently. One fundamental issue arises in how to derive model parameters reliably from image data of varying quality. This issue is even more challenging for advanced diffusion methods such as diffusion kurtosis imaging (DKI). Recently, deep learning-based methods have been demonstrated with their potential for robust and efficient computation of diffusion-derived measures. Inspired by these approaches, the current study specifically designed a framework based on a three-dimensional hierarchical convolutional neural network, to jointly reconstruct and harmonize DKI measures from multicenter acquisition to reformulate these to a state-of-the-art hardware using data from traveling subjects. The results from the harmonized data acquired with different protocols show that: 1) the inter-scanner variation of DKI measures within white matter was reduced by 51.5% in mean kurtosis, 65.9% in axial kurtosis, 53.7% in radial kurtosis, and 61.5% in kurtosis fractional anisotropy, respectively; 2) data reliability of each single scanner was enhanced and brought to the level of the reference scanner; and 3) the harmonization network was able to reconstruct reliable DKI values from high data variability. Overall the results demonstrate the feasibility of the proposed deep learning-based method for DKI harmonization and help to simplify the protocol setup procedure for multicenter scanners with different hardware and software configurations.
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Affiliation(s)
- Qiqi Tong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China; Research Center for Healthcare Data Science, Zhejiang Lab, Hangzhou, Zhejiang, China.
| | - Ting Gong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Hongjian He
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Zheng Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, CAS Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, China.
| | - Wenwen Yu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, State Key Laboratory of Neuroscience, CAS Key Laboratory of Primate Neurobiology, Chinese Academy of Sciences, Shanghai, China.
| | - Jianjun Zhang
- Department of Radiology, Zhejiang Hospital, Hangzhou, Zhejiang, China
| | - Lihao Zhai
- Department of Radiology, Zhejiang Hospital, Hangzhou, Zhejiang, China
| | - Hongsheng Cui
- Department of Radiology, The Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Xin Meng
- Department of Radiology, The Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang, China
| | - Chantal W M Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom.
| | - Jianhui Zhong
- Center for Brain Imaging Science and Technology, Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrumental Science, Zhejiang University, Hangzhou, Zhejiang, China; Department of Imaging Sciences, University of Rochester, Rochester, NY, USA.
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Giraudo C, Cavaliere A, Lupi A, Guglielmi G, Quaia E. Established paths and new avenues: a review of the main radiological techniques for investigating sarcopenia. Quant Imaging Med Surg 2020; 10:1602-1613. [PMID: 32742955 PMCID: PMC7378089 DOI: 10.21037/qims.2019.12.15] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/19/2019] [Indexed: 12/18/2022]
Abstract
Sarcopenia is a clinical condition mainly affecting the elderly that can be associated in a long run with severe consequences like malnutrition and frailty. Considering the progressive ageing of the world population and the socio-economic impact of this disease, much effort is devoted and has to be further focused on an early and accurate diagnostic assessment of muscle loss. Currently, several radiological techniques can be applied for evaluating sarcopenia. If dual-energy X-ray absorptiometry (DXA) is still considered the main tool and it is even recommended as reference by the most current guidelines of the European working group on sarcopenia in older people (EWGSOP), the role of ultrasound (US), computed tomography (CT), peripheral quantitative CT (pQCT), and magnetic resonance imaging (MRI) should not be overlooked. Indeed, such techniques can provide robust qualitative and quantitative information. In particular, regarding MRI, the use of sequences like diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), magnetic resonance spectroscopy (MRS) and mapping that could provide further insights into the physiopathological features of sarcopenia, should be fostered. In an era pointing to the quantification and automatic evaluation of diseases, we call for future research extending the application of organ tailored protocols, taking advantage of the most recent technical developments.
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Affiliation(s)
- Chiara Giraudo
- Radiology Institute, Department of Medicine—DIMED, University of Padova, Padova, Italy
| | - Annachiara Cavaliere
- Radiology Institute, Department of Medicine—DIMED, University of Padova, Padova, Italy
| | - Amalia Lupi
- Radiology Institute, Department of Medicine—DIMED, University of Padova, Padova, Italy
| | - Giuseppe Guglielmi
- Department of Radiology, Scientific Institute “Casa Sollievo della Sofferenza” Hospital, University of Foggia, Foggia, Italy
| | - Emilio Quaia
- Radiology Institute, Department of Medicine—DIMED, University of Padova, Padova, Italy
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18
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Assessment of cognitive and neural recovery in survivors of pediatric brain tumors in a pilot clinical trial using metformin. Nat Med 2020; 26:1285-1294. [PMID: 32719487 DOI: 10.1038/s41591-020-0985-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 06/19/2020] [Indexed: 02/06/2023]
Abstract
We asked whether pharmacological stimulation of endogenous neural precursor cells (NPCs) may promote cognitive recovery and brain repair, focusing on the drug metformin, in parallel rodent and human studies of radiation injury. In the rodent cranial radiation model, we found that metformin enhanced the recovery of NPCs in the dentate gyrus, with sex-dependent effects on neurogenesis and cognition. A pilot double-blind, placebo-controlled crossover trial was conducted (ClinicalTrials.gov, NCT02040376) in survivors of pediatric brain tumors who had been treated with cranial radiation. Safety, feasibility, cognitive tests and MRI measures of white matter and the hippocampus were evaluated as endpoints. Twenty-four participants consented and were randomly assigned to complete 12-week cycles of metformin (A) and placebo (B) in either an AB or BA sequence with a 10-week washout period at crossover. Blood draws were conducted to monitor safety. Feasibility was assessed as recruitment rate, medication adherence and procedural adherence. Linear mixed modeling was used to examine cognitive and MRI outcomes as a function of cycle, sequence and treatment. We found no clinically relevant safety concerns and no serious adverse events associated with metformin. Sequence effects were observed for all cognitive outcomes in our linear mixed models. For the subset of participants with complete data in cycle 1, metformin was associated with better performance than placebo on tests of declarative and working memory. We present evidence that a clinical trial examining the effects of metformin on cognition and brain structure is feasible in long-term survivors of pediatric brain tumors and that metformin is safe to use and tolerable in this population. This pilot trial was not intended to test the efficacy of metformin for cognitive recovery and brain growth, but the preliminary results are encouraging and warrant further investigation in a large multicenter phase 3 trial.
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19
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Van Dyck P, Billiet T, Desbuquoit D, Verdonk P, Heusdens CH, Roelant E, Sijbers J, Froeling M. Diffusion tensor imaging of the anterior cruciate ligament graft following reconstruction: a longitudinal study. Eur Radiol 2020; 30:6673-6684. [PMID: 32666318 DOI: 10.1007/s00330-020-07051-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/19/2020] [Accepted: 06/29/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To longitudinally monitor remodeling of human autograft following anterior cruciate ligament (ACL) reconstruction with DTI. METHODS Twenty-eight patients underwent DTI follow-up at 3, 8, and 14 months after clinically successful ACL reconstruction with tendon autograft. Among these, 18 patients had a concomitant lateral extra-articular procedure (LET). DTI data from 7 healthy volunteers was also obtained. Diffusion parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, AD; and radial diffusivity, RD) were evaluated within the fiber tractography volumes of the ACL graft and posterior cruciate ligament (PCL) in all patients. Data were analyzed using a linear mixed-effects model with post hoc testing using Bonferroni-Holm correction for multiple testing. The effect of additional LET was studied. RESULTS The ACL graft showed a significant decrease of FA over time (F = 4.00, p = 0.025), while the diffusivities did not significantly change over time. For PCL there were no significant DTI changes over time. A different evolution over time between patients with and without LET was noted for all diffusivity values of the ACL graft with reduced AD values in patients with LET at 8 months postoperatively (p = 0.048; adjusted p = 0.387). DTI metrics of the ACL graft differed largely from both native ACL and tendon at 14 months postoperatively. CONCLUSION Our study has shown the potential of DTI to longitudinally monitor the remodeling process in human ACL reconstruction. DTI analysis indicates that graft remodeling is incomplete at 14 months postoperatively. KEY POINTS • DTI can be used to longitudinally monitor the remodeling process in human ACL reconstruction. • DTI analysis indicates that autograft remodeling is incomplete at 14 months postoperatively. • DTI may be helpful for evaluating new ACL treatments.
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Affiliation(s)
- Pieter Van Dyck
- Department of Radiology, Antwerp University Hospital and University of Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium.
| | - Thibo Billiet
- Icometrix, Kolonel Begaultlaan 1b, 3012, Leuven, Belgium
| | - Damien Desbuquoit
- Department of Radiology, Antwerp University Hospital and University of Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium
| | - Peter Verdonk
- Monica Orthopedic Research (MoRe) Foundation, Monica Hospital, Stevenslei 20, 2100, Deurne, Belgium
| | - Christiaan H Heusdens
- Department of Orthopedics, Antwerp University Hospital and University of Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium
| | - Ella Roelant
- Clinical Trial Center (CTC), CRC Antwerp, Antwerp University Hospital and University of Antwerp, Wilrijkstraat 10, 2650, Edegem, Belgium
| | - Jan Sijbers
- Imec-Vision Lab, Department of Physics, University of Antwerp, Universiteitsplein 1, 2610, Wilrijk, Belgium
| | - Martijn Froeling
- Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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20
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Nielles-Vallespin S, Scott A, Ferreira P, Khalique Z, Pennell D, Firmin D. Cardiac Diffusion: Technique and Practical Applications. J Magn Reson Imaging 2019; 52:348-368. [PMID: 31482620 DOI: 10.1002/jmri.26912] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 12/12/2022] Open
Abstract
The 3D microarchitecture of the cardiac muscle underlies the mechanical and electrical properties of the heart. Cardiomyocytes are arranged helically through the depth of the wall, and their shortening leads to macroscopic torsion, twist, and shortening during cardiac contraction. Furthermore, cardiomyocytes are organized in sheetlets separated by shear layers, which reorientate, slip, and shear during macroscopic left ventricle (LV) wall thickening. Cardiac diffusion provides a means for noninvasive interrogation of the 3D microarchitecture of the myocardium. The fundamental principle of MR diffusion is that an MRI signal is attenuated by the self-diffusion of water in the presence of large diffusion-encoding gradients. Since water molecules are constrained by the boundaries in biological tissue (cell membranes, collagen layers, etc.), depicting their diffusion behavior elucidates the shape of the myocardial microarchitecture they are embedded in. Cardiac diffusion therefore provides a noninvasive means to understand not only the dynamic changes in cardiac microstructure of healthy myocardium during cardiac contraction but also the pathophysiological changes in the presence of disease. This unique and innovative technology offers tremendous potential to enable improved clinical diagnosis through novel microstructural and functional assessment. in vivo cardiac diffusion methods are immediately translatable to patients, opening new avenues for diagnostic investigation and treatment evaluation in a range of clinically important cardiac pathologies. This review article describes the 3D microstructure of the LV, explains in vivo and ex vivo cardiac MR diffusion acquisition and postprocessing techniques, as well as clinical applications to date. Level of Evidence: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019. J. Magn. Reson. Imaging 2020;52:348-368.
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Affiliation(s)
- Sonia Nielles-Vallespin
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Andrew Scott
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Pedro Ferreira
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Zohya Khalique
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Dudley Pennell
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - David Firmin
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
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21
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Chung S, Fieremans E, Wang X, Kucukboyaci NE, Morton CJ, Babb J, Amorapanth P, Foo FYA, Novikov DS, Flanagan SR, Rath JF, Lui YW. White Matter Tract Integrity: An Indicator of Axonal Pathology after Mild Traumatic Brain Injury. J Neurotrauma 2019; 35:1015-1020. [PMID: 29239261 DOI: 10.1089/neu.2017.5320] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
We seek to elucidate the underlying pathophysiology of injury sustained after mild traumatic brain injury (mTBI) using multi-shell diffusion magnetic resonance imaging, deriving compartment-specific white matter tract integrity (WMTI) metrics. WMTI allows a more biophysical interpretation of white matter (WM) changes by describing microstructural characteristics in both intra- and extra-axonal environments. Thirty-two patients with mTBI within 30 days of injury and 21 age- and sex-matched controls were imaged on a 3 Tesla magnetic resonance scanner. Multi-shell diffusion acquisition was performed with five b-values (250-2500 sec/mm2) along 6-60 diffusion encoding directions. Tract-based spatial statistics (TBSS) was used with family-wise error (FWE) correction for multiple comparisons. TBSS results demonstrated focally lower intra-axonal diffusivity (Daxon) in mTBI patients in the splenium of the corpus callosum (sCC; p < 0.05, FWE-corrected). The area under the curve value for Daxon was 0.76 with a low sensitivity of 46.9% but 100% specificity. These results indicate that Daxon may be a useful imaging biomarker highly specific for mTBI-related WM injury. The observed decrease in Daxon suggests restriction of the diffusion along the axons occurring shortly after injury.
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Affiliation(s)
- Sohae Chung
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - Els Fieremans
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - Xiuyuan Wang
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - Nuri E Kucukboyaci
- 3 Department of Rehabilitation Medicine, New York University School of Medicine , New York, New York
| | - Charles J Morton
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - James Babb
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - Prin Amorapanth
- 3 Department of Rehabilitation Medicine, New York University School of Medicine , New York, New York
| | - Farng-Yang A Foo
- 4 Department of Neurology, New York University Langone Health , New York, New York
| | - Dmitry S Novikov
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
| | - Steven R Flanagan
- 3 Department of Rehabilitation Medicine, New York University School of Medicine , New York, New York
| | - Joseph F Rath
- 3 Department of Rehabilitation Medicine, New York University School of Medicine , New York, New York
| | - Yvonne W Lui
- 1 Department of Radiology, Center for Advanced Imaging Innovation and Research, New York University School of Medicine , New York, New York.,2 Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine , New York, New York
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22
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Chung S, Wang X, Fieremans E, Rath JF, Amorapanth P, Foo FYA, Morton CJ, Novikov DS, Flanagan SR, Lui YW. Altered Relationship between Working Memory and Brain Microstructure after Mild Traumatic Brain Injury. AJNR Am J Neuroradiol 2019; 40:1438-1444. [PMID: 31371359 DOI: 10.3174/ajnr.a6146] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 06/19/2019] [Indexed: 01/05/2023]
Abstract
BACKGROUND AND PURPOSE Working memory impairment is one of the most troubling and persistent symptoms after mild traumatic brain injury (MTBI). Here we investigate how working memory deficits relate to detectable WM microstructural injuries to discover robust biomarkers that allow early identification of patients with MTBI at the highest risk of working memory impairment. MATERIALS AND METHODS Multi-shell diffusion MR imaging was performed on a 3T scanner with 5 b-values. Diffusion metrics of fractional anisotropy, diffusivity and kurtosis (mean, radial, axial), and WM tract integrity were calculated. Auditory-verbal working memory was assessed using the Wechsler Adult Intelligence Scale, 4th ed, subtests: 1) Digit Span including Forward, Backward, and Sequencing; and 2) Letter-Number Sequencing. We studied 19 patients with MTBI within 4 weeks of injury and 20 healthy controls. Tract-Based Spatial Statistics and ROI analyses were performed to reveal possible correlations between diffusion metrics and working memory performance, with age and sex as covariates. RESULTS ROI analysis found a significant positive correlation between axial kurtosis and Digit Span Backward in MTBI (Pearson r = 0.69, corrected P = .04), mainly present in the right superior longitudinal fasciculus, which was not observed in healthy controls. Patients with MTBI also appeared to lose the normal associations typically seen in fractional anisotropy and axonal water fraction with Letter-Number Sequencing. Tract-Based Spatial Statistics results also support our findings. CONCLUSIONS Differences between patients with MTBI and healthy controls with regard to the relationship between microstructure measures and working memory performance may relate to known axonal perturbations occurring after injury.
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Affiliation(s)
- S Chung
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
| | - X Wang
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
| | - E Fieremans
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
| | - J F Rath
- Department of Rehabilitation Medicine (J.F.R., P.A., S.R.F.), New York University School of Medicine, New York, New York
| | - P Amorapanth
- Department of Rehabilitation Medicine (J.F.R., P.A., S.R.F.), New York University School of Medicine, New York, New York
| | - F-Y A Foo
- Department of Neurology (F.-Y.A.F.), New York University Langone Health, New York, New York
| | - C J Morton
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
| | - D S Novikov
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
| | - S R Flanagan
- Department of Rehabilitation Medicine (J.F.R., P.A., S.R.F.), New York University School of Medicine, New York, New York
| | - Y W Lui
- From the Center for Advanced Imaging Innovation and Research & Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology (S.C., X.W., E.F., C.J.M., D.S.N., Y.W.L.)
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23
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Tax CM, Grussu F, Kaden E, Ning L, Rudrapatna U, John Evans C, St-Jean S, Leemans A, Koppers S, Merhof D, Ghosh A, Tanno R, Alexander DC, Zappalà S, Charron C, Kusmia S, Linden DE, Jones DK, Veraart J. Cross-scanner and cross-protocol diffusion MRI data harmonisation: A benchmark database and evaluation of algorithms. Neuroimage 2019; 195:285-299. [PMID: 30716459 PMCID: PMC6556555 DOI: 10.1016/j.neuroimage.2019.01.077] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 01/16/2019] [Accepted: 01/30/2019] [Indexed: 01/01/2023] Open
Abstract
Diffusion MRI is being used increasingly in studies of the brain and other parts of the body for its ability to provide quantitative measures that are sensitive to changes in tissue microstructure. However, inter-scanner and inter-protocol differences are known to induce significant measurement variability, which in turn jeopardises the ability to obtain 'truly quantitative measures' and challenges the reliable combination of different datasets. Combining datasets from different scanners and/or acquired at different time points could dramatically increase the statistical power of clinical studies, and facilitate multi-centre research. Even though careful harmonisation of acquisition parameters can reduce variability, inter-protocol differences become almost inevitable with improvements in hardware and sequence design over time, even within a site. In this work, we present a benchmark diffusion MRI database of the same subjects acquired on three distinct scanners with different maximum gradient strength (40, 80, and 300 mT/m), and with 'standard' and 'state-of-the-art' protocols, where the latter have higher spatial and angular resolution. The dataset serves as a useful testbed for method development in cross-scanner/cross-protocol diffusion MRI harmonisation and quality enhancement. Using the database, we compare the performance of five different methods for estimating mappings between the scanners and protocols. The results show that cross-scanner harmonisation of single-shell diffusion data sets can reduce the variability between scanners, and highlight the promises and shortcomings of today's data harmonisation techniques.
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Affiliation(s)
- Chantal Mw Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom.
| | - Francesco Grussu
- Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, United Kingdom; Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom
| | - Enrico Kaden
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom
| | - Lipeng Ning
- Harvard Medical School, Boston, MA, United States
| | - Umesh Rudrapatna
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - C John Evans
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Samuel St-Jean
- Image Sciences Institute, Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Alexander Leemans
- Image Sciences Institute, Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Simon Koppers
- Department of Radiology, University of Pennsylvania and the Children's Hospital of Philadelphia, Philadelphia, PA, United States; Institute of Imaging & Computer Vision, RWTH Aachen University, Aachen, Germany
| | - Dorit Merhof
- Institute of Imaging & Computer Vision, RWTH Aachen University, Aachen, Germany
| | - Aurobrata Ghosh
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom
| | - Ryutaro Tanno
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom; Machine Intelligence and Perception Group, Microsoft Research Cambridge, Cambridge, United Kingdom
| | - Daniel C Alexander
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, United Kingdom
| | - Stefano Zappalà
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Cyril Charron
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Slawomir Kusmia
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - David Ej Linden
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom; Mary McKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
| | - Jelle Veraart
- New York University, New York, NY, United States; imec-Vision Lab, Department of Physics, University of Antwerp, Antwerp, Belgium
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24
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Bells S, Lefebvre J, Longoni G, Narayanan S, Arnold DL, Yeh EA, Mabbott DJ. White matter plasticity and maturation in human cognition. Glia 2019; 67:2020-2037. [PMID: 31233643 DOI: 10.1002/glia.23661] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/21/2019] [Accepted: 05/29/2019] [Indexed: 12/17/2022]
Abstract
White matter plasticity likely plays a critical role in supporting cognitive development. However, few studies have used the imaging methods specific to white matter tissue structure or experimental designs sensitive to change in white matter necessary to elucidate these relations. Here we briefly review novel imaging approaches that provide more specific information regarding white matter microstructure. Furthermore, we highlight recent studies that provide greater clarity regarding the relations between changes in white matter and cognition maturation in both healthy children and adolescents and those with white matter insult. Finally, we examine the hypothesis that white matter is linked to cognitive function via its impact on neural synchronization. We test this hypothesis in a population of children and adolescents with recurrent demyelinating syndromes. Specifically, we evaluate group differences in white matter microstructure within the optic radiation; and neural phase synchrony in visual cortex during a visual task between 25 patients and 28 typically developing age-matched controls. Children and adolescents with demyelinating syndromes show evidence of myelin and axonal compromise and this compromise predicts reduced phase synchrony during a visual task compared to typically developing controls. We investigate one plausible mechanism at play in this relationship using a computational model of gamma generation in early visual cortical areas. Overall, our findings show a fundamental connection between white matter microstructure and neural synchronization that may be critical for cognitive processing. In the future, longitudinal or interventional studies can build upon our knowledge of these exciting relations between white matter, neural communication, and cognition.
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Affiliation(s)
- Sonya Bells
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Jérémie Lefebvre
- Krembil Research Institute, University Health Network, Toronto, Ontario, Canada.,Department of Mathematics, University of Toronto, Toronto, Ontario, Canada
| | - Giulia Longoni
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | - Sridar Narayanan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Douglas L Arnold
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Eleun Ann Yeh
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Paediatrics, University of Toronto, Toronto, Ontario, Canada
| | - Donald J Mabbott
- Neurosciences and Mental Health Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Psychology, University of Toronto, Toronto, Ontario, Canada
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25
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David S, Heemskerk AM, Corrivetti F, Thiebaut de Schotten M, Sarubbo S, Corsini F, De Benedictis A, Petit L, Viergever MA, Jones DK, Mandonnet E, Axer H, Evans J, Paus T, Leemans A. The Superoanterior Fasciculus (SAF): A Novel White Matter Pathway in the Human Brain? Front Neuroanat 2019; 13:24. [PMID: 30890921 PMCID: PMC6412356 DOI: 10.3389/fnana.2019.00024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 02/07/2019] [Indexed: 01/01/2023] Open
Abstract
Fiber tractography (FT) using diffusion magnetic resonance imaging (dMRI) is widely used for investigating microstructural properties of white matter (WM) fiber-bundles and for mapping structural connections of the human brain. While studying the architectural configuration of the brain's circuitry with FT is not without controversy, recent progress in acquisition, processing, modeling, analysis, and visualization of dMRI data pushes forward the reliability in reconstructing WM pathways. Despite being aware of the well-known pitfalls in analyzing dMRI data and several other limitations of FT discussed in recent literature, we present the superoanterior fasciculus (SAF), a novel bilateral fiber tract in the frontal region of the human brain that-to the best of our knowledge-has not been documented. The SAF has a similar shape to the anterior part of the cingulum bundle, but it is located more frontally. To minimize the possibility that these FT findings are based on acquisition or processing artifacts, different dMRI data sets and processing pipelines have been used to describe the SAF. Furthermore, we evaluated the configuration of the SAF with complementary methods, such as polarized light imaging (PLI) and human brain dissections. The FT results of the SAF demonstrate a long pathway, consistent across individuals, while the human dissections indicate fiber pathways connecting the postero-dorsal with the antero-dorsal cortices of the frontal lobe.
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Affiliation(s)
- Szabolcs David
- Image Sciences Institute, University Medical Center Utrecht and Utrecht University, Utrecht, Netherlands
| | - Anneriet M. Heemskerk
- Image Sciences Institute, University Medical Center Utrecht and Utrecht University, Utrecht, Netherlands
| | | | | | - Silvio Sarubbo
- Structural and Functional Connectivity Lab Project, Department of Emergency, Division of Neurosurgery, “S. Chiara” Hospital, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy
| | - Francesco Corsini
- Structural and Functional Connectivity Lab Project, Department of Emergency, Division of Neurosurgery, “S. Chiara” Hospital, Azienda Provinciale per i Servizi Sanitari (APSS), Trento, Italy
| | - Alessandro De Benedictis
- Department of Neurosciences, Division of Neurosurgery, “Bambino Gesù” Children Hospital, IRCCS, Rome, Italy
| | - Laurent Petit
- Groupe d’Imagerie Neurofonctionnelle (GIN), Institut des Maladies Neurodégératives (IMN)-UMR5293-CNRS, CEA, Université de Bordeaux, Bordeaux, France
| | - Max A. Viergever
- Image Sciences Institute, University Medical Center Utrecht and Utrecht University, Utrecht, Netherlands
| | - Derek K. Jones
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff, United Kingdom
| | | | - Hubertus Axer
- Hans Berger Department of Neurology, Jena University Hospital, Friedrich-Schiller University Jena, Jena, Germany
| | - John Evans
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff, United Kingdom
| | - Tomáš Paus
- Bloorview Research Institute, Holland Bloorview Kids Rehabilitation Hospital, Toronto, ON, Canada
- Departments of Psychology and Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht and Utrecht University, Utrecht, Netherlands
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26
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Chu CY, Sun CY, Kuai ZX, Yang F, Zhu YM. Structure Prior Constrained Estimation of Human Cardiac Diffusion Tensors. IEEE Trans Biomed Eng 2019; 66:3220-3230. [PMID: 30843792 DOI: 10.1109/tbme.2019.2902381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE The purpose of this paper is to increase the accuracy of human cardiac diffusion tensor (DT) estimation in diffusion magnetic resonance imaging (dMRI) with a few diffusion gradient directions. METHODS A structure prior constrained (SPC) method is proposed. The method consists in introducing two regularizers in the conventional nonlinear least squares estimator. The two regularizers penalize the dissimilarity between neighboring DTs and the difference between estimated and prior fiber orientations, respectively. A novel numerical solution is presented to ensure the positive definite estimation. RESULTS Experiments on ex vivo human cardiac data show that the SPC method is able to well estimate DTs at most voxels, and is superior to state-of-the-art methods in terms of the mean errors of principal eigenvector, second eigenvector, helix angle, transverse angle, fractional anisotropy, and mean diffusivity. CONCLUSION The SPC method is a practical and reliable alternative to current denoising- or regularization-based methods for the estimation of human cardiac DT. SIGNIFICANCE The SPC method is able to accurately estimate human cardiac DTs in dMRI with a few diffusion gradient directions.
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27
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Jones DK, Alexander DC, Bowtell R, Cercignani M, Dell'Acqua F, McHugh DJ, Miller KL, Palombo M, Parker GJM, Rudrapatna US, Tax CMW. Microstructural imaging of the human brain with a 'super-scanner': 10 key advantages of ultra-strong gradients for diffusion MRI. Neuroimage 2018; 182:8-38. [PMID: 29793061 DOI: 10.1016/j.neuroimage.2018.05.047] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 12/13/2022] Open
Abstract
The key component of a microstructural diffusion MRI 'super-scanner' is a dedicated high-strength gradient system that enables stronger diffusion weightings per unit time compared to conventional gradient designs. This can, in turn, drastically shorten the time needed for diffusion encoding, increase the signal-to-noise ratio, and facilitate measurements at shorter diffusion times. This review, written from the perspective of the UK National Facility for In Vivo MR Imaging of Human Tissue Microstructure, an initiative to establish a shared 300 mT/m-gradient facility amongst the microstructural imaging community, describes ten advantages of ultra-strong gradients for microstructural imaging. Specifically, we will discuss how the increase of the accessible measurement space compared to a lower-gradient systems (in terms of Δ, b-value, and TE) can accelerate developments in the areas of 1) axon diameter distribution mapping; 2) microstructural parameter estimation; 3) mapping micro-vs macroscopic anisotropy features with gradient waveforms beyond a single pair of pulsed-gradients; 4) multi-contrast experiments, e.g. diffusion-relaxometry; 5) tractography and high-resolution imaging in vivo and 6) post mortem; 7) diffusion-weighted spectroscopy of metabolites other than water; 8) tumour characterisation; 9) functional diffusion MRI; and 10) quality enhancement of images acquired on lower-gradient systems. We finally discuss practical barriers in the use of ultra-strong gradients, and provide an outlook on the next generation of 'super-scanners'.
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Affiliation(s)
- D K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK; School of Psychology, Faculty of Health Sciences, Australian Catholic University, Melbourne, Victoria, 3065, Australia.
| | - D C Alexander
- Centre for Medical Image Computing (CMIC), Department of Computer Science, UCL (University College London), Gower Street, London, UK; Clinical Imaging Research Centre, National University of Singapore, Singapore
| | - R Bowtell
- Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, UK
| | - M Cercignani
- Department of Psychiatry, Brighton and Sussex Medical School, Brighton, UK
| | - F Dell'Acqua
- Natbrainlab, Department of Neuroimaging, King's College London, London, UK
| | - D J McHugh
- Division of Informatics, Imaging and Data Sciences, The University of Manchester, Manchester, UK; CRUK and EPSRC Cancer Imaging Centre in Cambridge and Manchester, Cambridge and Manchester, UK
| | - K L Miller
- Oxford Centre for Functional MRI of the Brain, University of Oxford, Oxford, UK
| | - M Palombo
- Centre for Medical Image Computing (CMIC), Department of Computer Science, UCL (University College London), Gower Street, London, UK
| | - G J M Parker
- Division of Informatics, Imaging and Data Sciences, The University of Manchester, Manchester, UK; CRUK and EPSRC Cancer Imaging Centre in Cambridge and Manchester, Cambridge and Manchester, UK; Bioxydyn Ltd., Manchester, UK
| | - U S Rudrapatna
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
| | - C M W Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF24 4HQ, UK
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28
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Schwartz M, Martirosian P, Steidle G, Erb M, Stemmer A, Yang B, Schick F. Volumetric assessment of spontaneous mechanical activities by simultaneous multi-slice MRI techniques with correlation to muscle fiber orientation. NMR IN BIOMEDICINE 2018; 31:e3959. [PMID: 30067885 DOI: 10.1002/nbm.3959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 05/16/2018] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
The purpose of this work was assessment of volumetric characteristics of spontaneous mechanical activities in musculature (SMAMs) by diffusion-weighted simultaneous multi-slice (DW-SMS) imaging and spatial correlation to anatomical structure, as revealed by fusion to fiber tractographic information derived from diffusion-tensor imaging (DTI). The feasibility of using DW-SMS to image spontaneous events in human musculature was assessed by phantom measurements. Series of DW-SMS images and DTI datasets were recorded from the resting calf of three human subjects. Simultaneously recorded SMAMs in multiple slices were analyzed regarding spatial extension by the Kolmogorov-Smirnov test. Direct correlation of spatial distribution of SMAMs and fiber orientation was investigated by mapping of muscle fibers to multi-slice SMAM datasets. The DW-SMS strategy allows simultaneous assessment of SMAMs in several slices of resting skeletal musculature, since 73.9% of SMAM-affected volumes have shown SMAMs in multiple DW-SMS slices. Spatial extension of SMAMs was highly correlated over different simultaneously recorded DW-SMS slices, and affected areas followed the orientation of muscle fibers with a connectivity ratio up to 57.18 ± 14.80% based on event count and connectivity count maps. In 89.2% of all SMAM-affected datasets muscle fiber connectivity was shown in at least two adjacent slices. Direct correlation between SMAMs in human lower leg musculature and underlying anatomical structure was revealed by high muscle fiber connectivity (89.2%). SMAMs have shown a wide distribution along the longitudinal muscle direction (73.9% in multiple DW-SMS slices) with direct involvement of muscle fibers. Correlation between SMAMs in multiple DW-SMS slices and crossing muscular fiber tracts provides evidence that SMAMs result from physiological processes in musculature. Fusion of DW-SMS with DTI facilitates non-invasive studies of muscle fiber involvement in SMAMs in resting muscle.
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Affiliation(s)
- Martin Schwartz
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany
- Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany
| | - Petros Martirosian
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany
| | - Günter Steidle
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany
| | - Michael Erb
- Biomedical Magnetic Resonance, University of Tübingen, Tübingen, Germany
| | | | - Bin Yang
- Institute of Signal Processing and System Theory, University of Stuttgart, Stuttgart, Germany
| | - Fritz Schick
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tübingen, Tübingen, Germany
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29
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Ades-Aron B, Veraart J, Kochunov P, McGuire S, Sherman P, Kellner E, Novikov DS, Fieremans E. Evaluation of the accuracy and precision of the diffusion parameter EStImation with Gibbs and NoisE removal pipeline. Neuroimage 2018; 183:532-543. [PMID: 30077743 DOI: 10.1016/j.neuroimage.2018.07.066] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 07/11/2018] [Accepted: 07/30/2018] [Indexed: 01/09/2023] Open
Abstract
This work evaluates the accuracy and precision of the Diffusion parameter EStImation with Gibbs and NoisE Removal (DESIGNER) pipeline, developed to identify and minimize common sources of methodological variability including: thermal noise, Gibbs ringing artifacts, Rician bias, EPI and eddy current induced spatial distortions, and motion-related artifacts. Following this processing pipeline, iterative parameter estimation techniques were used to derive diffusion parameters of interest based on the diffusion tensor and kurtosis tensor. We evaluated accuracy using a software phantom based on 36 diffusion datasets from the Human Connectome project and tested the precision by analyzing data from 30 healthy volunteers scanned three times within one week. Preprocessing with both DESIGNER or a standard pipeline based on smoothing (instead of noise removal) improved parameter precision by up to a factor of 2 compared to preprocessing with motion correction alone. When evaluating accuracy, we report average decreases in bias (deviation from simulated parameters) over all included regions for fractional anisotropy, mean diffusivity, mean kurtosis, and axonal water fraction of 9.7%, 8.7%, 4.2%, and 7.6% using DESIGNER compared to the standard pipeline, demonstrating that preprocessing with DESIGNER improves accuracy compared to other processing methods.
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Affiliation(s)
- Benjamin Ades-Aron
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, NY, USA.
| | - Jelle Veraart
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, NY, USA.
| | - Peter Kochunov
- Department of Psychiatry, University of Maryland School of Medicine, MD, USA
| | - Stephen McGuire
- U.S. Air Force School of Aerospace Medicine, Aeromedical Research Department, 2510 5th Street, Building 840, Wright-Patterson AFB, OH, 45433-7913, USA
| | - Paul Sherman
- U.S. Air Force School of Aerospace Medicine, Aeromedical Research Department, 2510 5th Street, Building 840, Wright-Patterson AFB, OH, 45433-7913, USA
| | - Elias Kellner
- Department of Diagnostic Radiology, University Medical Center Freiburg, Freiburg, Germany
| | - Dmitry S Novikov
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, NY, USA
| | - Els Fieremans
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, NY, USA
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Sairanen V, Leemans A, Tax CMW. Fast and accurate Slicewise OutLIer Detection (SOLID) with informed model estimation for diffusion MRI data. Neuroimage 2018; 181:331-346. [PMID: 29981481 DOI: 10.1016/j.neuroimage.2018.07.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 05/22/2018] [Accepted: 07/02/2018] [Indexed: 12/23/2022] Open
Abstract
The accurate characterization of the diffusion process in tissue using diffusion MRI is greatly challenged by the presence of artefacts. Subject motion causes not only spatial misalignments between diffusion weighted images, but often also slicewise signal intensity errors. Voxelwise robust model estimation is commonly used to exclude intensity errors as outliers. Slicewise outliers, however, become distributed over multiple adjacent slices after image registration and transformation. This challenges outlier detection with voxelwise procedures due to partial volume effects. Detecting the outlier slices before any transformations are applied to diffusion weighted images is therefore required. In this work, we present i) an automated tool coined SOLID for slicewise outlier detection prior to geometrical image transformation, and ii) a framework to naturally interpret data uncertainty information from SOLID and include it as such in model estimators. SOLID uses a straightforward intensity metric, is independent of the choice of the diffusion MRI model, and can handle datasets with a few or irregularly distributed gradient directions. The SOLID-informed estimation framework prevents the need to completely reject diffusion weighted images or individual voxel measurements by downweighting measurements with their degree of uncertainty, thereby supporting convergence and well-conditioning of iterative estimation algorithms. In comprehensive simulation experiments, SOLID detects outliers with a high sensitivity and specificity, and can achieve higher or at least similar sensitivity and specificity compared to other tools that are based on more complex and time-consuming procedures for the scenarios investigated. SOLID was further validated on data from 54 neonatal subjects which were visually inspected for outlier slices with the interactive tool developed as part of this study, showing its potential to quickly highlight problematic volumes and slices in large population studies. The informed model estimation framework was evaluated both in simulations and in vivo human data.
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Affiliation(s)
- Viljami Sairanen
- Department of Physics, University of Helsinki, Helsinki, Finland; HUS Medical Imaging Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
| | - A Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands
| | - C M W Tax
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, United Kingdom
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Nath V, Schilling KG, Hainline AE, Parvathaneni P, Blaber JA, Lyu I, Anderson AW, Kang H, Newton AT, Rogers BP, Landman BA. SHARD: Spherical Harmonic-based Robust Outlier Detection for HARDI Methods. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2018; 10574:105740X. [PMID: 29887661 PMCID: PMC5991608 DOI: 10.1117/12.2293727] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
High Angular Resolution Diffusion Imaging (HARDI) models are used to capture complex intra-voxel microarchitectures. The magnetic resonance imaging sequences that are sensitized to diffusion are often highly accelerated and prone to motion, physiologic, and imaging artifacts. In diffusion tensor imaging, robust statistical approaches have been shown to greatly reduce these adverse factors without human intervention. Similar approaches would be possible with HARDI methods, but robust versions of each distinct HARDI approach would be necessary. To avoid the computational and pragmatic burdens of creating individual robust HARDI analysis variants, we propose a robust outlier imputation model to mitigate outliers prior to traditional HARDI analysis. This model uses a weighted spherical harmonic fit of diffusion weighted magnetic resonance imaging scans to estimate the values which had been corrupted during acquisition to restore them. Briefly, spherical harmonics of 6th order were used to generate basis function which were weighted by diffusion signal for detection of outliers. For validation, a single healthy volunteer was scanned for a single session comprising of two scans one without head movement and the other with deliberate head movement at a b-value of 3000 s/mm2 with 64 diffusion weighted directions with a single b0 (5 averages) per scan. The deliberate motion from the volunteer created natural artifacts in the acquisition of one of the scans. The imputation model shows reduction in root mean squared error of the raw signal intensities and improvement for the HARDI method Q-ball in terms of the Angular Correlation Coefficient. The results reveal that there is quantitative and qualitative improvement. The proposed model can be used as general pre-processing model before implementing any HARDI model in general to restore the artifacts which are created because of the outlier diffusion signal in certain gradient volumes.
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Affiliation(s)
- Vishwesh Nath
- Computer Science, Vanderbilt University, Nashville, TN
| | - Kurt G Schilling
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, TN
| | | | | | - Justin A Blaber
- Computer Science, Vanderbilt University, Nashville, TN
- Electrical Engineering, Vanderbilt University, TN
| | - Ilwoo Lyu
- Computer Science, Vanderbilt University, Nashville, TN
| | - Adam W Anderson
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, TN
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University, TN
| | - Allen T Newton
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, TN
| | - Baxter P Rogers
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, TN
| | - Bennett A Landman
- Computer Science, Vanderbilt University, Nashville, TN
- Electrical Engineering, Vanderbilt University, TN
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Weighted Mean of Signal Intensity for Unbiased Fiber Tracking of Skeletal Muscles: Development of a New Method and Comparison With Other Correction Techniques. Invest Radiol 2018; 52:488-497. [PMID: 28240621 DOI: 10.1097/rli.0000000000000364] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVES The aim of this study was to investigate the origin of random image artifacts in stimulated echo acquisition mode diffusion tensor imaging (STEAM-DTI), assess the role of averaging, develop an automated artifact postprocessing correction method using weighted mean of signal intensities (WMSIs), and compare it with other correction techniques. MATERIALS AND METHODS Institutional review board approval and written informed consent were obtained. The right calf and thigh of 10 volunteers were scanned on a 3 T magnetic resonance imaging scanner using a STEAM-DTI sequence.Artifacts (ie, signal loss) in STEAM-based DTI, presumably caused by involuntary muscle contractions, were investigated in volunteers and ex vivo (ie, human cadaver calf and turkey leg using the same DTI parameters as for the volunteers). An automated postprocessing artifact correction method based on the WMSI was developed and compared with previous approaches (ie, iteratively reweighted linear least squares and informed robust estimation of tensors by outlier rejection [iRESTORE]). Diffusion tensor imaging and fiber tracking metrics, using different averages and artifact corrections, were compared for region of interest- and mask-based analyses. One-way repeated measures analysis of variance with Greenhouse-Geisser correction and Bonferroni post hoc tests were used to evaluate differences among all tested conditions. Qualitative assessment (ie, images quality) for native and corrected images was performed using the paired t test. RESULTS Randomly localized and shaped artifacts affected all volunteer data sets. Artifact burden during voluntary muscle contractions increased on average from 23.1% to 77.5% but were absent ex vivo. Diffusion tensor imaging metrics (mean diffusivity, fractional anisotropy, radial diffusivity, and axial diffusivity) had a heterogeneous behavior, but in the range reported by literature. Fiber track metrics (number, length, and volume) significantly improved in both calves and thighs after artifact correction in region of interest- and mask-based analyses (P < 0.05 each). Iteratively reweighted linear least squares and iRESTORE showed equivalent results, but WMSI was faster than iRESTORE. Muscle delineation and artifact load significantly improved after correction (P < 0.05 each). CONCLUSIONS Weighted mean of signal intensity correction significantly improved STEAM-based quantitative DTI analyses and fiber tracking of lower-limb muscles, providing a robust tool for musculoskeletal applications.
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Chung S, Fieremans E, Kucukboyaci NE, Wang X, Morton CJ, Novikov DS, Rath JF, Lui YW. Working Memory And Brain Tissue Microstructure: White Matter Tract Integrity Based On Multi-Shell Diffusion MRI. Sci Rep 2018; 8:3175. [PMID: 29453439 PMCID: PMC5816650 DOI: 10.1038/s41598-018-21428-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 02/05/2018] [Indexed: 11/30/2022] Open
Abstract
Working memory is a complex cognitive process at the intersection of sensory processing, learning, and short-term memory and also has a general executive attention component. Impaired working memory is associated with a range of neurological and psychiatric disorders, but very little is known about how working memory relates to underlying white matter (WM) microstructure. In this study, we investigate the association between WM microstructure and performance on working memory tasks in healthy adults (right-handed, native English speakers). We combine compartment specific WM tract integrity (WMTI) metrics derived from multi-shell diffusion MRI as well as diffusion tensor/kurtosis imaging (DTI/DKI) metrics with Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) subtests tapping auditory working memory. WMTI is a novel tool that helps us describe the microstructural characteristics in both the intra- and extra-axonal environments of WM such as axonal water fraction (AWF), intra-axonal diffusivity, extra-axonal axial and radial diffusivities, allowing a more biophysical interpretation of WM changes. We demonstrate significant positive correlations between AWF and letter-number sequencing (LNS), suggesting that higher AWF with better performance on complex, more demanding auditory working memory tasks goes along with greater axonal volume and greater myelination in specific regions, causing efficient and faster information process.
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Affiliation(s)
- Sohae Chung
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA
| | - Els Fieremans
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA
| | | | - Xiuyuan Wang
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA
| | - Charles J Morton
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA
| | - Dmitry S Novikov
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA
| | - Joseph F Rath
- Department of Rehabilitation Medicine, New York University School of Medicine, New York, NY, 10016, USA
| | - Yvonne W Lui
- Department of Radiology, Center for Advanced Imaging Innovation and Research (CAI2R), New York University School of Medicine, New York, NY, 10016, USA.
- Department of Radiology, Bernard and Irene Schwartz Center for Biomedical Imaging, New York University School of Medicine, New York, NY, 10016, USA.
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Zivari Adab H, Chalavi S, Beets IAM, Gooijers J, Leunissen I, Cheval B, Collier Q, Sijbers J, Jeurissen B, Swinnen SP, Boisgontier MP. White matter microstructural organisation of interhemispheric pathways predicts different stages of bimanual coordination learning in young and older adults. Eur J Neurosci 2018; 47:446-459. [DOI: 10.1111/ejn.13841] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 12/22/2017] [Accepted: 01/17/2018] [Indexed: 01/30/2023]
Affiliation(s)
- Hamed Zivari Adab
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
| | - Sima Chalavi
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
| | - Iseult A. M. Beets
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
- BrainCTR; Lilid bvba; Diest Belgium
| | - Jolien Gooijers
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
| | - Inge Leunissen
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
| | - Boris Cheval
- Department of General Internal Medicine, Rehabilitation and Geriatrics; University of Geneva; Geneva Switzerland
- Swiss NCCR “LIVES - Overcoming Vulnerability: Life Course Perspectives”; University of Geneva; Geneva Switzerland
| | | | - Jan Sijbers
- iMinds Vision Lab; University of Antwerp; Antwerp Belgium
| | - Ben Jeurissen
- iMinds Vision Lab; University of Antwerp; Antwerp Belgium
| | - Stephan P. Swinnen
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
| | - Matthieu P. Boisgontier
- Movement Control and Neuroplasticity Research Group; Department of Movement Sciences; KU Leuven; Tervuurse Vest 101 Leuven Belgium
- Brain Behavior Laboratory; University of British Columbia; Vancouver BC Canada
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Kjølby B, Khan A, Chuhutin A, Pedersen L, Jensen J, Jakobsen S, Zeidler D, Sangill R, Nyengaard J, Jespersen S, Hansen B. Fast diffusion kurtosis imaging of fibrotic mouse kidneys. NMR IN BIOMEDICINE 2016; 29:1709-1719. [PMID: 27731906 PMCID: PMC5123986 DOI: 10.1002/nbm.3623] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 07/25/2016] [Accepted: 08/17/2016] [Indexed: 05/16/2023]
Abstract
Diffusion kurtosis imaging (DKI) is sensitive to tissue microstructure and may therefore be useful in the diagnosis and monitoring of disease in brain and body organs. Generally, diffusion magnetic resonance imaging (dMRI) in the body is challenging because of the heterogeneous body composition, which can cause image artefacts as a result of chemical shifts and susceptibility differences. In addition, the abdomen possesses physiological factors (e.g. breathing, heartbeat, blood flow) which may severely reduce image quality, especially when echo planar imaging is employed, as is typical in dMRI. Collectively, these challenging measurement conditions impede the use and exploration of DKI in the body. This impediment is further exacerbated by the traditionally large amount of data required for DKI and the low signal-to-noise ratio at the b-values needed to effectively probe the kurtosis regime. Recently introduced fast DKI techniques reduce the challenge of DKI in the body by decreasing the data requirement substantially, so that, for example, triggering and breath-hold techniques may be applied for the entire DKI acquisition without causing unfeasible scan times. One common pathological condition for which body DKI may be of immediate clinical value is kidney fibrosis, which causes progressive changes in organ microstructure. With its sensitivity to microstructure, DKI is an obvious candidate for a non-invasive evaluation method. We present preclinical evidence indicating that the rapidly obtainable tensor-derived mean kurtosis ( W̅) distinguishes moderately fibrotic kidneys from healthy controls. The presence and degree of fibrosis are confirmed by histology, which also indicates fibrosis as the main driver behind the DKI differences observed between groups. We therefore conclude that fast kurtosis is a likely candidate for an MRI-based method for the detection and monitoring of renal fibrosis. We provide protocol recommendations for fast renal DKI in humans based on a b-value optimisation performed using data acquired at 3 T in normal human kidney.
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Affiliation(s)
- B.F. Kjølby
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - A.R. Khan
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - A. Chuhutin
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - L. Pedersen
- Research Laboratory for Biochemical Pathology, Aarhus University Hospital, Department of Clinical Medicine, Aarhus, Denmark
| | - J.B. Jensen
- The PET centre, Aarhus University Hospital, Aarhus, Denmark
| | - S. Jakobsen
- The PET centre, Aarhus University Hospital, Aarhus, Denmark
| | - D. Zeidler
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - R. Sangill
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - J.R Nyengaard
- Stereology and Electron Microscopy Laboratory, Centre for Stochastic Geometry and Advanced Bioimaging, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - S.N. Jespersen
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - B. Hansen
- Center of Functionally Integrative Neuroscience (CFIN) and MINDLab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Corresponding Author: Brian Hansen, CFIN, Aarhus University, Building 10G, 5th Floor, Nørrebrogade 44, DK-8000 Århus C, Denmark,
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Andersson JLR, Graham MS, Zsoldos E, Sotiropoulos SN. Incorporating outlier detection and replacement into a non-parametric framework for movement and distortion correction of diffusion MR images. Neuroimage 2016; 141:556-572. [PMID: 27393418 DOI: 10.1016/j.neuroimage.2016.06.058] [Citation(s) in RCA: 419] [Impact Index Per Article: 52.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 05/25/2016] [Accepted: 06/30/2016] [Indexed: 12/13/2022] Open
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Jelescu IO, Zurek M, Winters KV, Veraart J, Rajaratnam A, Kim NS, Babb JS, Shepherd TM, Novikov DS, Kim SG, Fieremans E. In vivo quantification of demyelination and recovery using compartment-specific diffusion MRI metrics validated by electron microscopy. Neuroimage 2016; 132:104-114. [PMID: 26876473 DOI: 10.1016/j.neuroimage.2016.02.004] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 12/15/2015] [Accepted: 02/04/2016] [Indexed: 12/01/2022] Open
Abstract
There is a need for accurate quantitative non-invasive biomarkers to monitor myelin pathology in vivo and distinguish myelin changes from other pathological features including inflammation and axonal loss. Conventional MRI metrics such as T2, magnetization transfer ratio and radial diffusivity have proven sensitivity but not specificity. In highly coherent white matter bundles, compartment-specific white matter tract integrity (WMTI) metrics can be directly derived from the diffusion and kurtosis tensors: axonal water fraction, intra-axonal diffusivity, and extra-axonal radial and axial diffusivities. We evaluate the potential of WMTI to quantify demyelination by monitoring the effects of both acute (6weeks) and chronic (12weeks) cuprizone intoxication and subsequent recovery in the mouse corpus callosum, and compare its performance with that of conventional metrics (T2, magnetization transfer, and DTI parameters). The changes observed in vivo correlated with those obtained from quantitative electron microscopy image analysis. A 6-week intoxication produced a significant decrease in axonal water fraction (p<0.001), with only mild changes in extra-axonal radial diffusivity, consistent with patchy demyelination, while a 12-week intoxication caused a more marked decrease in extra-axonal radial diffusivity (p=0.0135), consistent with more severe demyelination and clearance of the extra-axonal space. Results thus revealed increased specificity of the axonal water fraction and extra-axonal radial diffusivity parameters to different degrees and patterns of demyelination. The specificities of these parameters were corroborated by their respective correlations with microstructural features: the axonal water fraction correlated significantly with the electron microscopy derived total axonal water fraction (ρ=0.66; p=0.0014) but not with the g-ratio, while the extra-axonal radial diffusivity correlated with the g-ratio (ρ=0.48; p=0.0342) but not with the electron microscopy derived axonal water fraction. These parameters represent promising candidates as clinically feasible biomarkers of demyelination and remyelination in the white matter.
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Affiliation(s)
- Ileana O Jelescu
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA.
| | - Magdalena Zurek
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Kerryanne V Winters
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Jelle Veraart
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Anjali Rajaratnam
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Nathanael S Kim
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - James S Babb
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Timothy M Shepherd
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Dmitry S Novikov
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Sungheon G Kim
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Els Fieremans
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
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38
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Veraart J, Fieremans E, Novikov DS. Diffusion MRI noise mapping using random matrix theory. Magn Reson Med 2015; 76:1582-1593. [PMID: 26599599 DOI: 10.1002/mrm.26059] [Citation(s) in RCA: 421] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/06/2015] [Accepted: 10/26/2015] [Indexed: 01/12/2023]
Abstract
PURPOSE To estimate the spatially varying noise map using a redundant series of magnitude MR images. METHODS We exploit redundancy in non-Gaussian distributed multidirectional diffusion MRI data by identifying its noise-only principal components, based on the theory of noisy covariance matrices. The bulk of principal component analysis eigenvalues, arising due to noise, is described by the universal Marchenko-Pastur distribution, parameterized by the noise level. This allows us to estimate noise level in a local neighborhood based on the singular value decomposition of a matrix combining neighborhood voxels and diffusion directions. RESULTS We present a model-independent local noise mapping method capable of estimating the noise level down to about 1% error. In contrast to current state-of-the-art techniques, the resultant noise maps do not show artifactual anatomical features that often reflect physiological noise, the presence of sharp edges, or a lack of adequate a priori knowledge of the expected form of MR signal. CONCLUSIONS Simulations and experiments show that typical diffusion MRI data exhibit sufficient redundancy that enables accurate, precise, and robust estimation of the local noise level by interpreting the principal component analysis eigenspectrum in terms of the Marchenko-Pastur distribution. Magn Reson Med 76:1582-1593, 2016. © 2015 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Jelle Veraart
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA. .,Department of Physics, iMinds-Vision Lab, University of Antwerp, Antwerp, Belgium.
| | - Els Fieremans
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
| | - Dmitry S Novikov
- Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA
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39
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Perrone D, Aelterman J, Pižurica A, Jeurissen B, Philips W, Leemans A. The effect of Gibbs ringing artifacts on measures derived from diffusion MRI. Neuroimage 2015; 120:441-55. [PMID: 26142273 DOI: 10.1016/j.neuroimage.2015.06.068] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/22/2015] [Accepted: 06/24/2015] [Indexed: 12/13/2022] Open
Abstract
Diffusion-weighted (DW) magnetic resonance imaging (MRI) is a unique method to investigate microstructural tissue properties noninvasively and is one of the most popular methods for studying the brain white matter in vivo. To obtain reliable statistical inferences with diffusion MRI, however, there are still many challenges, such as acquiring high-quality DW-MRI data (e.g., high SNR and high resolution), careful data preprocessing (e.g., correcting for subject motion and eddy current induced geometric distortions), choosing the appropriate diffusion approach (e.g., diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), or diffusion spectrum MRI), and applying a robust analysis strategy (e.g., tractography based or voxel based analysis). Notwithstanding the numerous efforts to optimize many steps in this complex and lengthy diffusion analysis pipeline, to date, a well-known artifact in MRI--i.e., Gibbs ringing (GR)--has largely gone unnoticed or deemed insignificant as a potential confound in quantitative DW-MRI analysis. Considering the recent explosion of diffusion MRI applications in biomedical and clinical applications, a systematic and comprehensive investigation is necessary to understand the influence of GR on the estimation of diffusion measures. In this work, we demonstrate with simulations and experimental DW-MRI data that diffusion estimates are significantly affected by GR artifacts and we show that an off-the-shelf GR correction procedure based on total variation already can alleviate this issue substantially.
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Affiliation(s)
- Daniele Perrone
- iMinds - Image Processing and Interpretation, Ghent University, Ghent, Belgium.
| | - Jan Aelterman
- iMinds - Image Processing and Interpretation, Ghent University, Ghent, Belgium
| | - Aleksandra Pižurica
- iMinds - Image Processing and Interpretation, Ghent University, Ghent, Belgium
| | - Ben Jeurissen
- iMinds - Vision Lab, Department of Physics, University of Antwerp, Belgium
| | - Wilfried Philips
- iMinds - Image Processing and Interpretation, Ghent University, Ghent, Belgium
| | - Alexander Leemans
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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Steidle G, Schick F. Addressing spontaneous signal voids in repetitive single-shot DWI of musculature: spatial and temporal patterns in the calves of healthy volunteers and consideration of unintended muscle activities as underlying mechanism. NMR IN BIOMEDICINE 2015; 28:801-810. [PMID: 25943431 DOI: 10.1002/nbm.3311] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 03/26/2015] [Accepted: 03/26/2015] [Indexed: 06/04/2023]
Abstract
Single-shot diffusion-weighted MRI sensitive to different types of incoherent motion inside tissue shows sporadic signal voids with a considerable size (>1 cm) in calf musculature at rest. Spatial and temporal patterns of these signal voids and their dependence on measurement conditions were tested systematically in order to obtain more insight into the underlying mechanism. Lower leg muscles of 10 healthy subjects were examined by recording series of 1000 echo-planar single-shot scans with repetition time 500 ms and b-value 100 s/mm(2) . Effects of strength and orientation of motion sensitization gradients and of repetition times were analysed. Potential influences of arterial blood pulsations and positioning of the subject were studied. Comparison of calf muscle groups showed more frequent signal voids in gastrocnemius and soleus muscle compared with tibialis muscles. Large inter-individual variance in the total number of signal voids visible in a transverse slice of the lower leg was observed (minimum 40/1000 scans; maximum >550/1000 scans). Typical sizes of the affected muscular areas ranged from 1.5 to 2.5 cm in the transverse and from 1.5 to 7 cm in the head-feet direction. Signal voids occurred nearly independent of the cardiac phase and with similar frequencies for supine and prone positions. Resting calf muscles show spontaneous signal voids in single-shot DWI at low b-values with an irregular temporal and spatial pattern. Values of mean diffusivity, diffusion tensor parameters, and IVIM-derived perfusion are expected to be clearly distorted by such signal voids if no rejection of affected data is applied. Several potential causes for the signal voids are discussed. The most probable explanation for the phenomenon is seen in the occurrence of spontaneous incoherent mechanical activity in musculature based on weak muscle fibre contractions. If this is the case it opens up a new field for studies on the physiological role and regulation of these unintended muscle activities.
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Affiliation(s)
- Günter Steidle
- Section on Experimental Radiology, Department of Radiology, University of Tübingen, Tübingen, Germany
| | - Fritz Schick
- Section on Experimental Radiology, Department of Radiology, University of Tübingen, Tübingen, Germany
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Dudink J, Pieterman K, Leemans A, Kleinnijenhuis M, van Cappellen van Walsum AM, Hoebeek FE. Recent advancements in diffusion MRI for investigating cortical development after preterm birth-potential and pitfalls. Front Hum Neurosci 2015; 8:1066. [PMID: 25653607 PMCID: PMC4301014 DOI: 10.3389/fnhum.2014.01066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 12/22/2014] [Indexed: 12/13/2022] Open
Abstract
Preterm infants are born during a critical period of brain maturation, in which even subtle events can result in substantial behavioral, motor and cognitive deficits, as well as psychiatric diseases. Recent evidence shows that the main source for these devastating disabilities is not necessarily white matter (WM) damage but could also be disruptions of cortical microstructure. Animal studies showed how moderate hypoxic-ischemic conditions did not result in significant neuronal loss in the developing brain, but did cause significantly impaired dendritic growth and synapse formation alongside a disturbed development of neuronal connectivity as measured using diffusion magnetic resonance imaging (dMRI). When using more advanced acquisition settings such as high-angular resolution diffusion imaging (HARDI), more advanced reconstruction methods can be applied to investigate the cortical microstructure with higher levels of detail. Recent advances in dMRI acquisition and analysis have great potential to contribute to a better understanding of neuronal connectivity impairment in preterm birth. We will review the current understanding of abnormal preterm cortical development, novel approaches in dMRI, and the pitfalls in scanning vulnerable preterm infants.
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Affiliation(s)
- J Dudink
- Department of Neonatology, Pediatric Intensive Care and Pediatric Radiology, Erasmus Medical Center - Sophia Children's Hospital Rotterdam, Netherlands
| | - K Pieterman
- Department of Neonatology, Pediatric Intensive Care and Pediatric Radiology, Erasmus Medical Center - Sophia Children's Hospital Rotterdam, Netherlands
| | - A Leemans
- Image Sciences Institute, University Medical Center Utrecht Utrecht, Netherlands
| | - M Kleinnijenhuis
- Oxford Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford Oxford, UK
| | - A M van Cappellen van Walsum
- Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center Nijmegen, Netherlands
| | - F E Hoebeek
- Department of Neuroscience, Erasmus Medical Center Rotterdam Rotterdam, Netherlands
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