The Combined Application Of Magnetic Resonance DTI And 3D-pcASL In Differential Diagnosis Of Hyper-acute And Acute Ischemic Cerebral Infarction

Objective:To explore the clinical value of magnetic resonance(MR)diffusion tensor imaging(DTI)combined with 3D pseudo continuous arterial spin labeling(3D-pc ASL)perfusion imaging in differential diagnosis of hyper-acute and acute ischemic cerebral infarction.Methods:To retrospective analysis DTI and 3D-pc ASL images of confirmed unilateral hyper-acute(16 patients,A group)and acute(30 patients,B group)ischemic cerebral infarction from January 2015 to December 2017.The data collected by the GE Discovery 750 W 3.0T MR(US)scanner and the DTI and 3D-pc ASL data analyzed by post-processing workstation.Measure the infarction area on diffusion weighted imaging(DWI)images(Square measure of infarction on DWI,SDWI)and abnormal perfusion area on cerebral blood flow(CBF)images(Square measure of infarction abnormal perfusion on CBF,SCBF)on the maximum infarction slice.Set the regions of interest(ROI)of infarction core(IC),mismatch area of SCBF and SDWI(MACD)and the corresponding contra based on DWI images.Record the CBF,fractional anisotropy(FA)and average diffusion coefficient(DCavg)values of each ROI and calculate the relative CBF(r CBF),relative FA(r FA)and relative DCavg(r DCavg)values of infarction lesion to contra.SCBF > SDWI means SCBF is larger than SDWI 10% or more,SCBF < SDWI means SCBF is smaller than SDWI 10% or less,otherwise it is regarded as SCBF ? SDWI.Analyze the CBF,FA and DCavg parameter values of patients with SCBF > SDWI and low perfusion in IC,and calculate the r CBF,r FA and r DCavg values.Select the IC and contra as the seed point to reconstruct the diffusion tensor tractography(DTT).When the ROI is selected,it can be considered that there is a large impact on the results due to the differences in the cerebral sulcus and vascular heterogeneity,which should be avoided as much as possible,while the contra ROI is automatically generated by the software.In addition,the ROI was placed based on a jointdecision by two attending physician from department of radiology and neurology with no knowing about situation of grouping.Compare each parameter value of IC,MACD with that of corresponding contra,also analyze the differences of relative parameters values between two groups,also,analyze the differential diagnosis efficiency of each relative parameter by the Receiver operating characteristic(ROC)curve.This study was approved by the ethics committee of our hospital,and each patient(or authorized family member)signed the informed consent.Results:The CBF and DCavg value of IC were lower than contra in both two groups,however,the FA value was only lower than contra in B group(P<0.05).The CBF value of MACD was reduced than contra in both two groups(P<0.05).The DCavg and FA values of MACD were lower and higher than contra respectively in A group(P<0.05).The r FA,r DCavg of IC and r FA of MACD were decreased in B group than that in A group,On the contrary,the r DCavg,r CBF of MACD were higher in B group than that in A group(P<0.05).ROC curve showed the best diagnosis cut off values for identifying two groups of r FA,r DCavg values of IC and r CBF,r FA,r DCavg values of MACD were 0.890,0.541 and 1.139,0.902,0.455,respectively.Conclusion:The clinic could apply the change mode of CBF,FA,DCavg values and relative values to differential diagnose hyper-acute and acute cerebral infarction,which could provide the basis for selecting more reasonable treatment project.