Evaluation of White Matter Microstructural Alterations in Patients with Post-Stroke Cognitive Impairment at the Sub-Acute Stage

Chunxue He,1,2,&ast; Mingqiang Gong,3,4,&ast; Gengxiao Li,1,2 Yunxia Shen,2 Longyin Han,5 Bin Han,6 Mingwu Lou2 1Shenzhen Clinical Medical College, Guangzhou University of Chinese Medicine, Shenzhen, People’s Republic of China; 2Department of Radiology, Longgang District Central Hospital of Shenzhen, Shenzhen, People’s Republic of China; 3The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, People’s Republic of China; 4Department of Acupuncture, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, People’s Republic of China; 5Department of Neurology, Beijing Longfu Hospital, Beijing, People’s Republic of China; 6Department of Rehabilitation Medicine, Longgang District Central Hospital of Shenzhen, Guangdong, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Bin Han; Mingwu Lou, Tel +86 13928488998 ; +86 13808854650, Email hhbb08@163.com; mingwulou@sina.comPurpose: To investigate white matter alterations in post-stroke cognitive impairment (PSCI) patients at the subacute stage employing diffusion kurtosis and tensor imaging.Methods: Thirty PSCI patients at the subacute phase and 30 healthy controls (HC) underwent diffusion kurtosis imaging (DKI) scans and neuropsychological assessments. Based on the tract-based spatial statistics and atlas-based ROI analysis, fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), kurtosis fractional anisotropy (KFA), axial kurtosis (AK), and radial kurtosis (RK) were compared in specific white matter fiber bundles between the groups (with family-wise error correction). Adjusting for age and gender, a partial correlation was conducted between neurocognitive assessments and DKI metrics in the PSCI group.Results: In comparison with the HC, PSCI patients significantly showed decreased MK, RK, and FA and increased MD values in the genu of corpus callosum, anterior limb internal capsule, and left superior corona radiata. In addition, DKI detected more white matter region changes in MK (31/48), KFA (40/48), and RK (25/48) than DTI with FA (28/48) and MD (21/48), which primarily consisted of the right cingulum, right superior longitudinal fasciculus, and left posterior limb of internal capsule. In the left anterior limb of internal capsule, MK and RK values were significantly negatively correlated with TMT-B (r = − 0.435 and − 0.414, P < 0.05), and KFA values (r = − 0.385, P < 0.05) of corpus callosum negatively associated with TMT-B.Conclusion: Combing DTI, DKI, and neuropsychological tests, we found extensive damaged white matter microstructure and poor execution performance in subacute PSCI patients. DKI could detect more subtle white matter changes than DTI metrics. Our findings provide added information for exploring the mechanisms of PSCI and conducting cognitive rehabilitation in the subacute stage.Keywords: diffusion kurtosis imaging, diffusion tensor imaging, subacute ischemic stroke, cognitive impairment