Evaluation Of White Matter Reorganization After Ischemic Stroke Using Diffusion Kurtosis Imaging

Object: Using MR diffusion kurtosis imaging to observe the change of white matter of middle cerebral artery territory infarction,to investigate correlation of white matter reorganization of chronic middle cerebral artery territory infarction with clinical outcome,and to investigate the value of DKI,and its quantitative parameters MK and FA in evaluation of white matter reorganization after ischemic stroke.Method: 1)12 patients who underwent brain MR examinations from 2015-8-19 to 2016-1-19,and both principal diagnoses and routine scan results were acute middle cerebral artery territory infarction,underwent routine brain MR examination and DKI scans at 2-7 days and 2-3 months after onset,respectively.DKI images were operated by DKE software to obtain FA maps and MK maps.FA maps and MK maps of the two scans were aligned.Selected perilesional region,bilateral centrum semiovale,corona radiata,PLIC,cerebral peduncle and corpus callosum splenium,body and genu as ROIs.ImageJ software was used to measure the FA and MK of the same ROIs of the two scans.Paired t-tests were used to examine the differences of FA and MK of each ROIs between the two scans by SPSS statistical software,respectively.2)23 patients who underwent brain MR examinations from 2015-8-19 to 2016-1-19,both principal diagnoses and routine scan results were acute middle cerebral artery territory infarction,and had hemiplegia symptom,were scored by mRS(modified Rankin Scale)in 2-3 months after onset,dichotomized as “good”(mRS score=0-2)or “poor”(mRS score=3-5).Then underwent routine brain MR examination and DKI scans.DKI images were operated by DKE software to obtain FA maps and MK maps.Selected perilesional region,bilateral centrum semiovale,corona radiata,PLIC,cerebral peduncle and corpus callosum splenium,body and genu as ROIs.ImageJ software was used to measure the FA and MK in each ROIs.Independent samples t-tests were used to examine the differences of FA and MK in each ROIs between two groups by SPSS statistical software,respectively.Result: 1)There were significant differences between the acute and chronic phase in FA and MK of perilesional region,ipsilateral PLIC and cerebral peduncle(P <0.05).There was significant difference between the acute and chronic phase in MK of ipsilateral centrum semiovale(P <0.05).There were no significant differences between the acute and chronic phase in FA of ipsilateral centrum semiovale,and in FA and MK of ipsilateral corona radiate,contralateral centrum semiovale,corona radiata,PLIC,cerebral peduncle and corpus callosum splenium,body and genu.2)There were significant differences between the two groups of outcomes in FA and MK of perilesional region and ipsilateral cerebral peduncle(P <0.05).There were no significant differences between two groups in FA and MK of bilateral centrum semiovale,corona radiata,PLIC,contralateral cerebral peduncle and corpus callosum splenium,body and genu.Conclusion: Changes in FA and MK of perilesional region and ipsilateral CST traveling region during rehabilitation of patients with middle cerebral artery territory infarction suggested that there might be white matter reorganization,and which might be connected with enhanced function.DKI proved the value in studying white matter reorganization.