White Matter Degeneration after Ischemic Stroke: A Longitudinal Diffusion Tensor Imaging Study

Visser, Milanka M.; Yassi, Nawaf; Campbell, Bruce; Desmond, Patricia; Davis, Stephen M.; Spratt, Neil J; Bivard, Andrew

doi:10.1111/jon.12556

Cited by 32 publications

(25 citation statements)

References 26 publications

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“…Diffusion MRI tractography is an indirect approach for inferring brain structural connectivity from the brownian motion of water molecules constrained by the axonal fiber architecture (Jeurissen, Descoteaux, Mori, & Leemans, 2017) . Thus, it provides the unique opportunity to investigate, in vivo and non invasively, the structural connectivity of intact or altered brains, such as in the case of stroke (Visser et al, 2018) , in longitudinal analysis of brain development (Hagmann et al, 2010) or in utero acquisitions of prenatal brain structure (Kasprian et al, 2008) . However, the reliability of diffusion MRI tractography for properly mapping structural connections remains highly debated (Jones, Knösche, & Turner, 2013;Thomas et al, 2014) .…”

Section: Introductionmentioning

confidence: 99%

Comparison between diffusion MRI tractography and histological tract-tracing of cortico-cortical structural connectivity in the ferret brain

Delettre

Messé

Dell

et al. 2019

Preprint

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The anatomical wiring of the brain is a central focus in network neuroscience. Diffusion MRI tractography offers the unique opportunity to investigate the brain fiber architecture in vivo and non invasively. However, its reliability is still highly debated. Here, we explored the ability of diffusion MRI tractography to match invasive anatomical tract-tracing connectivity data of the ferret brain. We also investigated the influence of several state-of-the-art tractography algorithms on this match to ground truth connectivity data. Tract-tracing connectivity data were obtained from retrograde tracer injections into the occipital, parietal and temporal cortices of adult ferrets. We found that the relative densities of projections identified from the anatomical experiments were highly correlated with the estimates from all the studied diffusion tractography algorithms (Spearman's rho ranging from 0.67 to 0.91), while only small, non-significant variations appeared across the tractography algorithms. These results are comparable to findings reported in mouse and monkey, increasing the confidence in diffusion MRI tractography results. Moreover, our results provide insights into the variations of sensitivity and specificity of the tractography algorithms and hence, into the influence of choosing one algorithm over another.

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Section: Introductionmentioning

confidence: 99%

Comparison between diffusion MRI tractography and histological tract-tracing of cortico-cortical structural connectivity in the ferret brain

Delettre

Messé

Dell

et al. 2019

Preprint

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“…The denoised DTI images were corrected for eddy currents using FSL' s eddycorrect, a tool for correcting distortion and motion [34]. After eddy correction, DTI images were corrected for B1 field inhomogeneities by using dwibiascorrect in MRtrix [35]. Fitting of diffusion tensor on corrected DTI data was done using dtifit of FMRIB' s diffusion toolbox.…”

Section: Data Processingmentioning

confidence: 99%

Enhanced Bidirectional Connectivity of the Subthalamo-pallidal Pathway in 6-OHDA-mouse Model of Parkinson's Disease Revealed by Probabilistic Tractography of Diffusion-weighted MRI at 9.4T

Kim

et al. 2020

Exp Neurobiol

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Parkinson' s disease (PD) is a common neurodegenerative disease of the central nervous system that primarily affects the motor system [1]. The most distinct motor symptoms of PD are gait impairments, tremor, muscular rigidity, slowness of movement as well as non-motor dysfunctions such as behavioral and cognitive impairments [2]. These symptoms of PD are caused by progres-sive loss of dopamine-producing cells in the substantia nigra pars compacta (SNc), one of five nuclei in the basal ganglia that plays a key role in voluntary movement [2,3]. As a result, dopamine levels are lowered, inhibiting innervation of basal ganglia output and dysfunction within the cortico-basal ganglia thalamic pathway [4].The basal ganglia is a network of subcortical nuclei, consisting of the striatum, internal and external globus pallidus (GPi/GPe), subthalamic nucleus (STN), substantia nigra compacta (SNc) and substantia nigra reticulata (SNr) [5]. Neural projections of the striatum involved in the motor system are segregated into direct and indirect pathways. It is believed that dopamine secreted from SNc activates striatal D1 neurons in the direct pathway and inhibits the striatal D2 neurons in the indirect pathway. In PD, dopamine depletion leads to diminished inhibitory direct pathway output An important challenge in Parkinson' s disease (PD) based neuroscience and neuroimaging is mapping the neuronal connectivity of the basal ganglia to understand how the disease affects brain circuitry. However, a majority of diffusion tractography studies have shown difficulties in revealing connections between distant anatomic brain regions and visualizing basal ganglia connectome. In this current study, we investigated the differences in basal ganglia connectivity between 6-OHDA induced ex-vivo PD mouse model and normal ex-vivo mouse model by using diffusion tensor imaging tractography from diffusion-weighted images obtained with a high resolution 9.4 T MR scanner. Connectivity pattern of the basal ganglia were compared between five 6-OHDA and five control ex-vivo mouse brains using results of probabilistic tractography generated with PROBTRACKX. When compared with control mouse, 6-OHDA mouse showed significant enhancements to motor territory-related subthalamopallidal and pallido-subthalamic connectivity. Multi-fiber tractography combined with diffusion MRI data has the potential to help recognize the abnormalities found in connectivity of psychiatric and neurologic disease models.

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“…Diffusion Tensor Images were acquired using a 3.0-Tesla Philips (Ingenia) Medical Systems equipped with a Synergy-L Sensitivity Encoding (SENSE) head coil, using a single echo planar imaging (EPI) sequence, 33 diffusion-weighted images (b = 1000 s/mm 2 ) and a reference T2-weighted image with no diffusion weighting (b = 0 s/mm 2 ) were obtained with the following acquisition parameters: voxel size =2×2×2 mm 3…”

Section: Image Acquisitionmentioning

confidence: 99%

“…Previous DTI researches in stroke patients calculated several diffusion tensor indicators (e.g. fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) ) in various regions along the corticospinal tract (CST) of the lesioned hemisphere and contralateral hemisphere [2,3], or computed the CST integrity [4,5]. These imaging indicators were later correlated to function outcomes, further establishing them as prediction markers.…”

Section: Introductionmentioning

confidence: 99%

Patterns of white matter degeneration in remote brain areas from the basal ganglion lesion of ischemic stroke patients with motor impairment

Cao¹,

Wang

Chen

et al. 2020

Preprint

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Background: Diffusion tensor imaging (DTI) studies have revealed distinct white matter characteristics of the brain following diseases. Beyond the lesion-symptom mapping, recent studies have demonstrated extensive structural and functional alterations of remote areas to local lesions caused by stroke in the brain. Here, we further investigated the structural changes from a global level using DTI data through multivariate pattern analysis (MVPA) and network-based statistic (NBS). Methods: Ten ischemic stroke patients with basal ganglia lesions and motor dysfunctions and eleven demographically matched adults as controls underwent brain Magnetic Resonance Imaging scans. DTI data were processed to obtain fractional anisotropy (FA) maps and MVPA was used to explore brain regions that play an important role in classification based on FA maps. The white matter (WM) structural network was constructed by the deterministic fiber tracking approach according to the Automated Anatomical Labeling (AAL) atlas. NBS was used to explore differences in structural networks between groups.Results: MVPA applied to FA images correctly identified stroke patients with a statistically significant accuracy of 100% (P≤0.001). Compared with the controls, the study patients showed FA reductions in the perilesional basal ganglia and brainstem, with a few showing reductions in bilateral frontal lobes. Using NBS, we found a significant decrease in FA-weighted WM subnetwork in stroke patients. Conclusions: We identified some patterns of WM degeneration affecting brain areas remote to the ischemic lesion, revealing the abnormal organization of WM network in stroke patients, which may be helpful for the understanding of the neural mechanisms of stroke sequela.

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White Matter Degeneration after Ischemic Stroke: A Longitudinal Diffusion Tensor Imaging Study

Abstract: White matter changes after stroke may be localized rather than a global phenomenon.

Cited by 32 publications

References 26 publications

Comparison between diffusion MRI tractography and histological tract-tracing of cortico-cortical structural connectivity in the ferret brain

Comparison between diffusion MRI tractography and histological tract-tracing of cortico-cortical structural connectivity in the ferret brain

Enhanced Bidirectional Connectivity of the Subthalamo-pallidal Pathway in 6-OHDA-mouse Model of Parkinson's Disease Revealed by Probabilistic Tractography of Diffusion-weighted MRI at 9.4T

Patterns of white matter degeneration in remote brain areas from the basal ganglion lesion of ischemic stroke patients with motor impairment

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