Study On The Multimodal Magnetic Resonance Imaging Of Cerebral Small Vascular Disease And The Correlation With Cognitive Impairment

CSVD is a progressive cerebrovascular disease,the most common in the elderly,is the most common cause of vascular dementia,and stroke etiology accounted for about 1/5,it not only can lead to stroke,the greater harm is the patients with progressive impairment of cognitive,emotional,gait and daily life ability.The importance,harm no less than atherosclerotic cerebrovascular disease,because of its progress with the occult,often even in patients with medical personnel ignored,at present the clinical diagnosis of CSVD is mainly made after the exclusion of other diseases,the imaging diagnosis and treatment standard of evidence has not yet so clear.In recent years it has become a hot research topic in the field of neurology.To discover and understand early neuroimaging features of cognitive disorders caused by CSVD,to prevent and delay the development of CSVD is of great significance.This research applicated of neuroimaging,multimodal SWI,DKI magnetic resonance imaging technology CSVD resolution characteristics,especially the neuroimaging change of early cognitive impairment,correlation analysis of brain microstructure changes and memory,behavior,executive function and other cognitive disorders,to further explore the differences between CSVD and macrovascular atherosclerotic cerebrovascular disease,early diagnosis and individualized treatment and progression of CSVD provide imaging basis.This study includes two parts: Part 1: Study on the application of SWI and DKI MRI techniques to evaluate CSVD microhaemorrhage and changes in brain microstructure and the correlation with cognitive impairmentObjective: To study the number,morphology and distribution characteristics of CSVD CMBs induced by SWI.We used DKI to evaluate the change of CSVD brain microstructure,and to analyze the difference between CSVD and macrovascular atherosclerotic cerebrovascular disease,and to explore the correlation between imaging features and cognitive impairment.Methods: Matched with age,gender,level of education,44 cases of small vascular disease24 cases of patients with vascular disease,16 healthy subjects in the Department of Neurology admitted to the first hospital of Jilin University Bethune,they underwent conventional MRI and DWI examination,who were performed SWI and DKI scan,as well as MMSE,Mo CA,ADL scale.The diagnosis,location,number and classification of cerebral microhemorrhage were analyzed by two neuroimaging doctors.Based on B = 0,1000,and 2000 s/mm2 all data,DKI parameter graphs are obtained by computer operations(MK,AK,RK,FA,MD,AD and RD).Use the Mricron tool in the DKI parameter map(MK,AK,RK,FA,MD,AD and RD)on manual delineation of region of interest,respectively on both sides of the head of caudate nucleus,posterior limb of internal capsule,thalamus,anterior horn of lateral ventricle,ventricular parameters after the next corner,corona radiate,semioval center and genu and splenium of corpus callosum,pons at above DKI.Result:(1)CMBs showed nodular,annular and punctate low signal on SWI.Most of them were <5mm in diameter,and some lesions were more than 10.0mm.The lesions were round or oval and not linear.The lesions found on SWI can be displayed on DWI b=0 images.Less CMBs can be displayed in plain scan T2 WI images,and the volume of lesions displayed on SWI is larger than those seen in DWI b=0 and T2 WI images.SWI is the best imaging method for displaying CMBs.In this study,the detection rate of c MBS in 44 cases of small vascular disease was 61.36%,and the detection rate of CMBs in 24 cases of large vessel disease was 54.17%.The good sites of CMBs are cortical and subcortical white matter,basal nucleus,thalamus,brain stem and cerebellum,and most of the patients CMBs exist in many parts of the brain.1 patients with multiple intracerebral CMBs were followed by hypertensive intracerebral hemorrhage in the basal ganglia.The number of CMBs in patients with SVD was related to the degree of blood pressure rise in the patients.The higher the level of hypertension,the more the number of CMBs.There is a certain correlation between the number of CMBs and the degree of cognitive impairment in SVD patients.The more the number of CMBs,the more serious the cognitive dysfunction is.(2)In this study,the genu of the corpus callosum(GC),splenium of corpus callosum(SC),left head of caudate nucleus(LBN),coronaradiate(LCR),left centrum ovale(LCS),the left posterior limb of the internal capsule(LIC),left para anteriorangle of lateral ventricle(LLA),left para posteriorangle of lateral ventricle(LLP)and left pons(LP),Left thalamus(LT),right caudate head(RBN)and right coronaradiata(RCR),right centrum ovale(RCS),right posterior limb of the internal capsule(RIC)and right para anteriorangle of lateral ventricle(RLA),right para posteriorangle of lateral ventricle(RLP)and right pons(RP),right thalamus(RT)in patients with SVD were selected as part of the region of interest(ROI).the FA of ROI decreases,MD,AD,RD,AK,MK value increased,RK value decreased.(3)when comparing between the groups,it was found that there was a significant difference between SVD and BVD and NC two groups(P values were 0.016 and 0.009).There was significant difference in FA value of the right caudate nucleus in the SVD and BVD groups with the same degree of cognitive impairment.The MD values of each group of SVD and BVD decreased in the two groups,indicating that the infarction is in the stage of angiogenic edema,and no longer is cytotoxic edema.This is consistent with the pathological change of cerebral ischemia and infarction in the chronic latent progress of SVD and the absence of large acute arterial occlusion in the ROI.In group SVD,MD,AD,RD values left thalamus had significant difference compared with BVD group(P=0.026,0.017,0.035),the reaction of water diffusion anisotropy change hypothesis with Gauss distribution in left thalamus area in SVD group and BVD group is different,suggesting the existence of special significance in the left thalamus about free water molecules diffusion,and the three groups of parameters show consistency.(4)in the study SVD and BVD group MK of each part decreased,indicating the complexity of the corresponding brain tissue structure damaged in the pathological state,SVD group left pons MK value decreased more obviously,there was significant difference compared with BVD group(P =0.036).(5)in this study,the left side of the bridge brain,the values of RK and AK in group SVD and BVD were significantly decreased,but there was no significant difference between the two groups.Conclusion:(1)SWI is the best imaging method of CMBs display;the number of CMBs of SVD patients with elevated blood pressure is related to the degree of hypertension,the higher the hypertension level,the more the number of CMBs;the number of CMBs has some correlation with SVD patients with cognitive dysfunction,the more the number of CMBs,the more serious cognitive impairment.CMBs can be used as a neuroimaging indicator of vascular cognitive impairment.(2)In the location of cerebral small vessel disease,the FA of ROI decreases to varying degrees,and the values of MD,AD and RD increase,and the values of MK,AK and RK decrease.This indicates that DKI can accurately reflect the complexity change of microstructure and reflect the change of microstructure of gray matter and white matter in brain tissue.(3)DKI display the organizational complexity of microstructure and the reaction of water molecules diffusion movement in brain tissue,SVD and BVD two group showed significant difference of diffusion anisotropy parameters MD,AD,RD values of the two groups have in left thalamus;kurtosis tensor parameter MK which reflect the reaction degree of complexity of the organizational structure has significant difference between the two groups in the left pons.It is suggested that the left thalamus and the part of the pons may have special significance in the reaction of the diffusion of water molecules in different pathological states,but the specific mechanism is not clear.(4)DKI derived parameters and cognitive evaluation scores are linearly correlated,DKI can reflect degree of cognitive impairment caused by cerebral small vessel disease,it is useful in cerebral small vessel disease early diagnosis,it is helpful to make individualized treatment and disease monitoring strategy,it is imaging signs of dynamic observation and prognostic assessment.Part 2: Study on the difference of the volume changes of the basal ganglia of CSVD and CBVDObjective: To explore the difference in the volume changes of the basal ganglia of the small vascular disease and the large vascular disease.Methods: 21 patients with SVD and 12 patients with BVD were selected.A 3T MR imaging system(Ingenia,Philips Healthcare)was used for image acquisition at the No.1 Hospital of Jilin University.T1-weighted and fluid attenuation inversion recovery(FLAIR)MRI scans were acquired at the axial plane with following parameters.T1-weighted sequence: TR = 2600 ms,TE = 20 ms,FA = 90°,inversion time(TI)= 1040 ms,acquisition matrix = 256×216,slices = 18,thickness = 7.0 mm and voxel size = 0.575×0.575×7 mm3;FLAIR sequence: TR = 7000 ms,TE = 93 ms,FA = 90°,inversion time(TI)= 2215 ms,acquisition matrix = 328×295,slices = 18,thickness = 7.0 mm and voxel size = 0.532×0.532×7 mm3.All the T1-weighted MRI scans were processed with Accu Brain?(Brain Now Medical Technology Limited,Hong Kong SAR),which is an automatic brain segmentation and quantification software with high performance among the existing automatic brain segmentation tools1.This software uses T1-weighted image as input and produces a brain quantification report containing several aspects of brain region information,such as volume,relative volume,percentile and asymmetry.We selected four typical brain regions in basal ganglia for the analyses of interest,including thalamus,caudate,putamen and pallidum.The volumes of these structures were measured on both sides of the brain,and then they were divided by the intracranial volume(ICV)for each subject as a normalization process for the subsequent analyses.Results:Regarding the volumetric measures of the basal ganglia structures,the total volume ratio of thalamus,the volume ratios of left thalamus,left and right putamen,and the total volume ratio of putamen presented significant differences between the BVD and the SVD group(uncorrected p<0.05).After multiple comparison correction with FDR,the volumetric differences in these regions were still mildly significant(p<0.10).Conclusion: There are differences in the volume of brain structure in basal ganglia between SVD and BVD.This difference reveals and confirms the difference between blood supply and pathophysiology of small vessel disease and macroangiopathy,and confirms the validity of DKI in diagnosing small vessel disease.