The Microstructural Status of the Corpus Callosum Is Associated with the Degree of Motor Function and Neurological Deficit in Stroke Patients

Abstract

Human neuroimaging studies and animal models have suggested that white matter damage from ischemic stroke leads to the functional and structural reorganization of perilesional and remote brain regions. However, the quantitative relationship between the transcallosal tract integrity and clinical motor performance score after stroke remains unexplored. The current study employed a tract-based spatial statistics (TBSS) analysis on diffusion tensor imaging (DTI) to investigate the relationship between white matter diffusivity changes and the clinical scores in stroke patients. Probabilistic fiber tracking was also used to identify structural connectivity patterns in the patients. Thirteen ischemic stroke patients and fifteen healthy control subjects participated in this study. TBSS analyses showed that the corpus callosum (CC) and bilateral corticospinal tracts (CST) in the stroke patients exhibited significantly decreased fractional anisotropy and increased axial and radial diffusivity compared with those of the controls. Correlation analyses revealed that the motor and neurological deficit scores in the stroke patients were associated with the value of diffusivity indices in the CC. Compared with the healthy control group, probabilistic fiber tracking analyses revealed that significant changes in the inter-hemispheric fiber connections between the left and right motor cortex in the stroke patients were primarily located in the genu and body of the CC, left anterior thalamic radiation and inferior fronto-occipital fasciculus, bilateral CST, anterior/superior corona radiate, cingulum and superior longitudinal fasciculus, strongly suggesting that ischemic induces inter-hemispheric network disturbances and disrupts the white matter fibers connecting motor regions. In conclusion, the results of the present study show that DTI-derived measures in the CC can be used to predict the severity of motor skill and neurological deficit in stroke patients. Changes in structural connectivity pattern tracking between the left and right motor areas, particularly in the body of the CC, might reflect functional reorganization and behavioral deficit.

Remote Lower White Matter Integrity Increases the Risk of Long-Term Cognitive Impairment After Ischemic Stroke in Young Adults

“…For instance, a lower white matter integrity of the corpus callosum in the contralesional hemisphere was associated with cognitive impairment. It seems that beside cognitive outcome, microstructural integrity of the corpus callosum has been found to predict the degree of motor function after stroke, 35 and therefore seems to be an important white matter structure for outcome after stroke.…”

Precentral degeneration and cerebellar compensation in amyotrophic lateral sclerosis: A multimodal MRI analysis

“…In particular, FA decreases within the corticospinal tract have been recognized as the pathologic hallmark feature in patients with ALS (Borsodi et al, 2017). On the other hand, the corpus callosum, as the largest WM structure interconnecting the two cerebral hemispheres (Li, Wu, Liang, & Huang, 2015), is thought to play an important role in interhemispheric communication. This speculation was further supported by our result of a positive correlation between mean FA of the significant clusters and ALSFRS-R scores in the patient group.…”

Diffusion Tensor Imaging Shows Corpus Callosum Differences between High‐Grade Gliomas and Metastases

“…Therefore, our results suggest that the patients’ brains have decreased myelination and fiber orientation in the body of the CC. These overall differences in DTI characteristics between healthy subjects and our patient population provide evidence that the CC is impacted by distal neuropathologies, potentially due to Wallerian Degeneration caused by the tumors …”