Evaluation Of MR3D-ASL Combined With IVIM And High Resolution MRA For Large Area Ischemic Cerebral Infarction

The health hazard of cerebrovascular diseases seriously affect the quality of life.The large-area ischemic cerebral infarction is prone to disability and death.The burden of social and economic caused by treatment and rehabilitation are enormous.With the development of medical Imaging and various inspection equipment functions,especially the technology of functional magnetic resonance imaging provides a rich and reliable diagnostic information for the diagnosis of cerebral infarction.MR Three-dimension arterial spin labeling(MR3D-ASL,3D-ASL)uses quasi-continuous radio frequency labeling technology to achieve three-dimensional acquisition,covering the whole brain at one time,and obtaining cerebral blood flow after post-treatment.Some scholars have shown that the technology of ASL is close to the sensitivity of drug perfusion in evaluating cerebral perfusion.Diffusion Weighted-imaging is a common technique for diagnosing acute and subacute cerebral infarction and has been widely used in clinical practice.Le Bihan et al.proposed the use of special DWI scans to separate the“Intravoxel Incoherent Motion(IVIM)”of water molecule motion.IVIM refers to the movement of water molecules in the same voxel containing multiple components of random motion of water molecules flowing from macroscopic liquid to microscopic,however,apparent diffusion coefficient measured by conventional DWI reflects mixed resuilt with various components.IVIM uses multiple b values to scan and fits with a bi-exponential model to obtain the simple diffusion coefficient(D),slow ADC,which reflects the slow diffusion of water molecules.false diffusion coefficient(D*),fastADC reflects perfusion correlation coefficient,and f value reflects the ratio of rapid diffusion to IVIM.Generally speaking,b<200s/mm~2 mainly reflects perfusion weight,and b>200s/mm~2 mainly reflects the diffusion weight.This technology has been applied to the evaluation of body and brain tumors,and the role of cerebral ischemic disease still needs a lot of research to determine its reliability.High Resolution Magnetic Resonance Angiography(HRMRA)has the advantages of safety,no drug fight,and clear imaging.This study used 3D-ASL technology combined with IVIM technology,and HRMRA to complete the examination of brain parenchyma and blood vessels in one stop.Evaluation of large area ischemic by contrasting technical parameters.Objective To explore the role of 3D-ASL combined with IVIM and high resolution MRA in assessing ischemic cerebral infarction.Methods Fifty patients with LAICI diagnosed from January 2015 to July 2017 were enrolled in this study.3D-ASL combined with IVIM and HRMRA were used to analyze the changes of cerebrovascular perfusion parameters.Results The diagnostic sensitivity and specificity of 3D-ASL+IVIM were 100.00%(25/25)and 100.00%(25/25)respectively,which were higher than that of 3D-ASL[88.00%(22/25),84.00%(21/25)]And IVIM[72.00%(18/25),64.00%(16/25)];3D-ASL in the infarct area showed a decrease in cerebral blood perfusion,CBF decreased,CBF in the infarct area was significantly lower than that in the contralateral side,and the difference was statistically significant(P<0.05).The IVIM parameters decrease in different degrees,and the ADC,D,D*and f values in the infarct area decrease,and the above parameters(except D*)are statistically significant(P<0.05).The correlation between rADC,rD,rD*and rf and rCBF was statistically significant except rD*(P<0.05).Conclusion 3D-ASL combined with IVIM and HRMRA has a high sensitivity and specificity in the diagnosis of large area ischemic cerebral infarction.It can accurately determine the low perfusion area of brain tissue and provide the basis for clinical early treatment and guidance medication.