The Application Value Of Susceptibility Weighted Imaging In Cerebral Microbleeds

Objective:To analyze the imaging characteristics of cerebral microbleeds,and to explore the application value of 3.0T MRI susceptibility weighted imaging for cerebral microbleeds,so as to provide certain reference value for clinical work and image differential diagnosis.Methods:From November 1,2018 to November 1,2019,the clinical and imaging data of patients with cerebral microbleeds factors that had completed conventional MRI sequence and SWI sequence scanning of skull in the Department of Neurology of the people's Hospital of Tibet Autonomous Region were collected.Among them,96 patients with cerebral microbleeds were confirmed by clinical history and imaging manifestations,with 1254 cerebral microbleeds lesions in total.All patients were Tibetan.The image data were agreed by the author,1 deputy chief physician and 1 chief physician.Analyze the signal characteristics of cerebral microbleeds on MRI routine sequence and SWI sequence.According to the location of the disease,cerebral microbleeds were divided into the cortical-subcortical region(A),the thalamus-basal ganglia(B)and the infratentorial region(C).The location,number and size of the lesions of cerebral microbleeds were recorded,and the correlation between the severity of cerebral microbleeds and the severity of common complications was analyzed.SPSS 19.0 software package was used for statistical analysis of the relevant data.The counting data was expressed by"n,%",the comparison between groups was performed by chi square test,the correlation analysis of the two orderly classified variables was performed by Goodman-Kruskal Gamma method(abbreviated as Gamma method),P<0.05 was statistically significant.This study had been approved by the ethics committee of our hospital,and the number of ethics review was ME-TBHP-19-17.Results:(1)The lesions of cerebral microbleeds were round or quasi round,uniform signal or concentric mixed signal with diameter less than1 cm.(2)At present,246 cases were collected,including 96 cases of cerebral microbleeds,the collected cerebral microbleeds patients were often accompanied with hypertension and lacunar infarction,and some patients were accompanied with CMS;71 cases of hypertension in 246cases,including 36 cases of cerebral microbleeds;66 cases of lacunar infarction in 246 cases,including 28 cases of cerebral microbleeds;37cases of CMS in 246 cases,including 19 cases of cerebral microbleeds;96 cases of cerebral microbleeds in 1254 lesions.(3)The positive rate of cerebral microbleeds detected by routine MRI and SWI sequence was compared.It was found that SWI sequence was significantly higher than that of routine sequence.The detection rate of cerebral microbleeds in each sequence was 13.2%in T1WI,16.7%in T2WI,19.5%in T2 Flair,33.3%in DWI and 100%in SWI.(4)According to the statistics of the location and distribution of cerebral microbleeds,the distribution of cerebral microbleeds was as follows:there were 73 cases of 599 lesions in the thalamus-basal ganglia,64 cases of 502 lesions in the cortical-subcortical region,37 cases of 153 lesions in the infratentorial region.(5)The size of different signal focus in CMBs was statistically analyzed and there were 1020 homogeneous signal focus and 234 mixed signal focus.The mixed signal focus usually appeared in the larger one.(6)According to the statistics of the distribution of cerebral microbleeds focus in patients with hypertension,lacunar infarction and CMS,there were 626cerebral microbleeds focus in 36 patients with hypertension,including228 in the cortical-subcortical region,311 in the deep region of brain and 87 in the infratentorial region;276 cerebral microbleeds focus in 28patients with lacunar infarction,including 110 in the cortical-subcortical region,129 in the deep region of brain and 37 in the infratentorial region;165 cerebral microbleeds focus in 19 patients with CMS,including97 in the cortical-subcortical region,54 in the deep region of brain and14 in the infratentorial region.(7)The detection rates of CMBs among different levels of hypertension,lacunar infarction and CMS were compared.?~2value of hypertension group was 11.506,P value was 0.010;?~2value of lacunar infarction group was 8.340,P value was 0.042;?~2value of CMS group was 8.574,P value was 0.032.(8)The correlation between the grading of cerebral microbleeds and the grading of hypertension,lacunar infarction and CMS was analyzed.The gamma coefficient of hypertension group was 0.355,P value:0.002<0.01;the gamma coefficient of lacunar infarction group was 0.144,P value:0.228;the gamma coefficient of CMS group was 0.276,P value:0.064.Conclusion:(1)The advantage of SWI sequence in the diagnosis of cerebral microbleeds was further confirmed.(2)Cerebral microbleeds were more likely to occur in the thalamus-basal ganglia and the cortical-subcortical region,but less in the infratentorial region.(3)The number of homogeneous signals in the focus of cerebral microbleeds was significantly larger than that of mixed signals,and mixed signals often appeared in the larger focus.(4)In patients with hypertension and lacunar infarction,the focus of cerebral microbleeds were more likely to occur in the deep region of brain,less in the infratentorial region.In patients with CMS,the focus of cerebral microbleeds were more likely to occur in the cortical-subcortical region.(5)By analyzing the correlation between the classification of cerebral microbleeds and the classification of hypertension,lacunar infarction and CMS,we found that there was a positive correlation between the classification of hypertension and the classification of cerebral microbleeds,the difference was statistically significant,but there was no statistical significance between the classification of lacunar infarction and CMS with the classification of cerebral microbleeds.