The Study Of Magnetic Resonance Diffusion Kurtosis Imaging Combined With Three-dimensional Arterial Spin Labeling In Cerebral Infarction

ObjectiveTo explore the changes of the images of acute cerebral infarction Diffusion kurtosis imaging,to explore the blood flow of abnormal parameters in DKI different parameter maps,and to compare the ability of DWI and DKI to evaluate the infarct core area,revealing DKI in the early stage,Revealing the value of DKI in the early diagnosis of ischemic stroke and judging the prognosis of patients.Materials and methods(1)Collected 66 patients with acute cerebral infarction who were hospitalized in the Second Affiliated Hospital of Guangxi Medical University from May 2018 to April 2019.All patients underwent MRI and DWI,DKI check.ADC,MD,AD,RD,MK,AK and RK functional maps are obtained after treatment,measuring the corresponding parameter values??of the brain lesion area and the mirror area brain tissue,and calculating The percentage change rate of each parameter value.Compare the difference between the percentage change rates of the various parameter values.(2)In the first part,62patients with acute cerebral infarction underwent DKI and ASL,and excluded24 patients with lesions less than 1.5 cm.38 patients with lesions greater than1.5 cm were excluded,and 7 of 38 large lesions were excluded.Patients with high perfusion lesions.A total of 31 patients showed that low-perfusion lesions(33 large lesions)were included in the standard.According to the MK and MD parameter maps,the degree of matching of abnormal ranges was shown.The two groups were MK/MD matching group and MD/MK mismatch group,which did not match.The lesions were divided into the peripheral area,the unmatched area and the central area from the outside to the inside.The matching group MD and the MK showed a signal abnormal range,which was divided into the peripheral area and the central area from the outside to the inside.The CBF value of perfusion hemodynamic parameters in brain tissue of different regions was normal.The normal control group had no abnormal signal brain tissue in the contralateral mirror area.The difference of CBF values??in different regions between MK/MD matching group and non-matching group was analyzed,and the difference of CBF values??between different regions in each group was analyzed.(3)A total of 13 patients were followed up.The routine MRI review time was 3 months after treatment.The area of??the final infarct was measured on the T2WI map.The differences in MK,MD and DWI lesions were compared.The correlation between initial infarct size and final infarct size were analyzed..Results(1)The ADC,MD,AD,and RD values??of the diffusion parameters in the lesions of patients with acute cerebral infarction were lower than that of the contralateral mirror area,the signal was more uniform,and the boundary was more blurred,while the MK,AK,and RK values??of each kurtosis parameter were higher than that of the contralateral mirror area(P<0.05),the signal is uneven or uniform,the boundary is clear,and the percentage change rate of each kurtosis parameter is greater than the percentage change rate of each diffusion parameter(P<0.05).The difference between the rate of change of kurtosis parameters and the rate of change of ADC was statistically significant(P<0.05).There was no significant difference in the percentage change rate between ADC and MD of diffusion parameters.The axial diffusion and kurtosis parameters changed.The rate was significantly greater than the rate of radial change(ie,the rate of change between the AK and RK,AD and RD was statistically significant,P<0.05).(2)In the acute cerebral infarction,the CBF values??of brain Lesion tissue in different regions were significantly lower than those in the contralateral side(P<0.05).There was a statistically significant difference in CBF between the central and the mismatched areas.The former was lower than the latter(P<0.05);the central area of??the lesion was lower than the surrounding area CBF,the difference was statistically significant(P<0.05),the former was lower than the latter;the lesion mismatched area and the surrounding area CBF value The difference was not statistically significant.The area of??MK,MD,DWI and T2WI lesions at the time of initial diagnosis were 332.67±633.17mm~2?842.67±1414.67mm~2?752.33±1090.00mm~2?453.33±768.50mm~2,and the lesion area of??most MD and DWI images was larger than that of MK.The difference was statistically significant(P<0.05).The volume of MK,MD,DWI lesions was significantly positively correlated with the infarct size of T2WI(r=0.967,0.879,0.868,P<0.05).The correlation between MK and T2WI lesion area was more significant than that of MD and T2WI,DWI and T2WI lesion area.ConclusionsCompared with traditional diffusion imaging,DKI can provide more abundant lesion information for patients with acute ischemic stroke,which is helpful for early diagnosis of patients.The MK/MD matching area of??early cerebral infarction has a lower CBF value than the MK/MD mismatched area,suggesting that MK can distinguish the tissues with different metabolic status in the MD abnormal signal area,which provides a reliable basis for DKI to accurately evaluate the infarct core area..The MK map is closer to the final infarct than the DWI map,providing more imaging information for more accurate definition of the infarct core region.