Wallerian Degeneration in the Corticospinal Tract Evaluated by Diffusion Tensor Imaging Correlates with Motor Deficit 30 Days after Middle Cerebral Artery Ischemic Stroke

Introduction: Manual scoring of behavior tests is commonly used for assessing motor deficits after stroke, however, it is labor intensive and subject to bias. These limitations lead to inconsistent assessment between research groups and non-reproducible data. In this study, we investigated the feasibility of an automated motor deficit assessment system, Erasmus ladder, in two ischemic stroke models. Methods: Distal middle cerebral artery occlusion (dMCAO n=10) or transient middle cerebral artery occlusion (tMCAO 30 minutes, n=15) were performed on male C57BL6J mice (11-13 weeks) to generate cortical ischemic stroke, with. Naïve mice (n=10) were used as controls. Immunohistochemistry was performed on brains collected at post-stroke day (PD) 30 to assess for infarct size (MAP2) and inflammation (CD68). Mice without infarct in both cortex and striatum were excluded from the study. Behavior was assessed using Erasmus ladder at pre-stroke baseline (4 unperturbed and 4 perturbed sessions) and on PD 7, 14, 21, and 28 (all perturbed sessions). Results: Erasmus ladder detected significant motor deficits in the tMCAO model, specifically in the pre- and post- perturbed times as well as several key step types (HH long). Analyses in the tMCAO model reveal changes in various step patterns and their capability to react to the perturbation (obstacle). These significant motor deficits after tMCAO were detectable until PD28. We also observed a sustained decline in the use of affected limb compared to unaffected limb until PD28. While this trend is also present in dMCAO model, motor deficits were detected in the dMCAO only at early timepoints (PD7) and the difference subsided by PD28. Conclusion: We have assessed the data collected by Erasmus ladder on mice that underwent two commonly used stroke models (tMCAO and dMCAO). Our data showed that Erasmus ladder can detect long term motor deficit including reduced use of affected limb, step pattern, and motor reaction to obstacle. This automated instrument is effective in detecting motor deficits in the tMCAO model and thus, can be used to evaluate treatments for enhancing recovery after stroke.

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Wallerian degeneration of the corticospinal tract in a middle cerebral artery infarction

Seminars in Cerebrovascular Diseases and Stroke ◽

10.1053/s1528-9931(01)80031-5 ◽

2001 ◽

Vol 1 (2) ◽

pp. 195-197

Author(s):

James D. Fleck ◽

Biagio Azzarelli ◽

José Biller

Keyword(s):

Middle Cerebral Artery ◽

Cerebral Artery ◽

Wallerian Degeneration ◽

Corticospinal Tract ◽

Middle Cerebral Artery Infarction

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Corticospinal tract mapping in children with ruptured arteriovenous malformations using functionally guided diffusion-tensor imaging

Journal of Neurosurgery Pediatrics ◽

10.3171/2012.1.peds11363 ◽

2012 ◽

Vol 9 (5) ◽

pp. 505-510 ◽

Cited By ~ 20

Author(s):

Michael J. Ellis ◽

James T. Rutka ◽

Abhaya V. Kulkarni ◽

Peter B. Dirks ◽

Elysa Widjaja

Keyword(s):

Diffusion Tensor Imaging ◽

Arteriovenous Malformations ◽

Corticospinal Tract ◽

Diffusion Tensor ◽

Imaging Techniques ◽

Neurological Deficits ◽

Motor Deficit ◽

Brain Anatomy ◽

Cortical Motor ◽

Tractography Data

Arteriovenous malformations (AVMs) can lead to distortion or reorganization of functional brain anatomy, making localization of eloquent white matter tracts challenging. To improve the accuracy of corticospinal tract (CST) mapping, recent studies have examined the use of functional imaging techniques to help localize cortical motor activations and use these as seed points to reconstruct CSTs using diffusion-tensor imaging (DTI). The authors examined the role of pretreatment functionally guided DTI CST mapping in 3 children with ruptured AVMs. In 2 patients, magnetoencephalography motor activations were adjacent to the nidus and/or hemorrhagic cavity. However, in 1 child, functional MRI motor activations were detected in both hemispheres, suggestive of partial transfer of cortical motor function. In all children, quantitative analysis showed that fractional anisotropy values and fiber density indices were reduced in the CSTs of the hemisphere harboring the AVM compared with the unaffected side. In 2 children, CST caliber was slightly diminished, corresponding to no motor deficit in 1 patient and a temporary motor deficit in the other. In contrast, 1 child demonstrated marked reduction and displacement of the CSTs, correlating with severe motor deficit. Preoperative motor tractography data were loaded onto the intraoperative neuronavigation platform to guide complete resection of the AVM in 2 cases without permanent neurological deficits. These preliminary results confirm the feasibility of CST mapping in children with ruptured AVMs using functionally guided DTI tractography. Prospective studies are needed to assess the full value of this technique in the risk stratification, prognosis, and multimodality management of pediatric AVMs.

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Prediction of Motor Recovery after Stroke by Assessment of Corticospinal Tract Wallerian Degeneration Using Diffusion Tensor Imaging

Indian Journal of Radiology and Imaging ◽

10.1055/s-0041-1729671 ◽

2021 ◽

Author(s):

Hoda Salah Darwish ◽

Rasha ElShafey ◽

Hanaa Kamel

Keyword(s):

Diffusion Tensor Imaging ◽

Effective Treatment ◽

Wallerian Degeneration ◽

Corticospinal Tract ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Motor Recovery ◽

Cerebral Stroke ◽

Limb Weakness ◽

Nihss Score

Abstract Aim of the Study To predict motor recovery after stroke by detection of diffusion tensor imaging (DTI) fractional anisotropy (FA) changes of corticospinal tract (CST) and correlate findings with clinical scores to provide more effective treatment and rehabilitation. Subjects and Methods Thirty patients with cerebral stroke were enrolled and underwent conventional magnetic resonance imaging and DTI at admission and 1 month after stroke. Mean diffusivity (MD), FA, FA ratio (rFA), and fiber number (FN) values of CST were calculated at the pons at admission and after 1 month of stroke. Three-dimensional reconstruction of bilateral CST and the structural changes of fibrous bands were observed. Severity of limb weakness was assessed by using the motor sub-index scores of the National Institutes of Health Stroke Scale (NIHSS) at admission, and after 1, 6, and 9 months for severity of limb weakness. Results The mean age of our patients was 61.32 ± 4.34 years, 17/30 (56.6%) were females, and 13/30 (43.4%) were males. In our study, 18/30 (60%) were hypertensive, 19/30 (63.3%) were diabetic, and 12/30 (40%) were smokers. A significant negative correlation was found between rFA and FN in the ipsilateral CST of the cerebral infarction at the rostral part of pons after 1 month of infarction and NIHSS score at 6 months (r = 0.377, p = 0.04 and r = 0.237, p = 0.02, respectively). However, a positive insignificant correlation was found between MD and NIHSS (r = 0.345, p = 0.635). The initial NIHSS score at the time of injury was 19.2 ± 4.3, which changed to 7.9 ± 2.4, 4.6 ± 1.9, and 3.3 ± 1.4 at 1, 6, and 9 months, respectively. Conclusion DTI is a sensitive tool for early detection of Wallerian degeneration in the CST after stroke, and can predict motor performance to provide effective treatment and rehabilitation to improve quality of life.

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