Corticospinal tract changes in acute brainstem ischemic stroke patients: A diffusion kurtosis imaging study

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Brainstem ischemic stroke can lead to significant motor pathway damage.
• Assessing microstructural changes in the corticospinal tract (CST) is crucial for understanding stroke-related deficits.

Purpose of the Study:

• To investigate corticospinal tract (CST) alterations in brainstem ischemic stroke patients using diffusion kurtosis imaging (DKI).
• To evaluate microstructural changes along the motor pathway at different anatomical levels.

Main Methods:

• Brain DKI was performed on 21 brainstem stroke patients and 21 healthy controls using a 3.0 T MRI scanner.
• Regions of interest were analyzed at the pons, posterior limb of the internal capsule (PLIC), corona radiata, and precentral gyrus.
• DKI parameters including fractional anisotropy (FA), mean diffusivity (MD), and mean kurtosis (MK) were measured.

Main Results:

• Patients showed decreased FA and MD, and increased MK on the ipsilateral side compared to the contralateral side.
• Contralateral MD values were significantly higher in patients than in controls.
• A decrease in contralateral FA was observed at the posterior limb of the internal capsule (PLIC) in stroke patients.

Conclusions:

• DKI can detect early microstructural changes in the motor pathway after brainstem stroke.
• These changes are not confined to the ipsilateral side; contralateral alterations are also present, particularly in the PLIC.
• DKI offers a valuable tool for assessing the extent of CST damage in stroke.