To Analyze Cerebral Infarction And Subtypes In Different Age Patients With Middle Cerebral Artery Stenosis Or Occlusive

Objective:To analyze the incidence of cerebral infarction and subtypes in different age patients with middle cerebral artery stenosis or occlusive in order to investigate the infarction mechanisms.Methods:Conventional MRI and MRA were performed in 195 cases, MCA stenosis or occlusive of all cases confirmed by MRA. Clinical data was counted respectively, including blood pressure, blood sugar, blood, lipin. According to age region, the patients were divided into two groups. One is the young-aged and middle-aged group, (≤59 years old), the other is the old-aged group (≥60 years old). Using a standardized method, rate of stenosis=[1-(Dstenos;s/Dnormal)]×100%, which measure the cerebral artery. According to rate of stenosis, the patients were divided into two groups, severe stenosis(70%-99%) or occlusion group, mild(under 50%) to moderate(50%-69%) stenosis group. To indentify the cerebral infarction subtypes according to diffusion-weighted imaging (DWI) and conventional T1WI and T2WI. Cerebral infarction was classified into 4 patterns:Cerebral Watershed infarction(CWSI), Territorial infarction(TI), Lacunar infarction(LI), Striatocapsular infarction(SCI). Counted the infarction rate and its subtypes, to analyze their correlation between the cerebral infarction and its subtypes with different age patients of MCA stenosis or occlusive. Different groups usingχ2 test, P<0.05 has significant difference, Statistical analysis was performed with the Statistical Package of Social Sciences 16.0 (SPSS16.0).Results:1.examine results:233 MCA stenosis or occlusions were observed in 195 patients, which involved unilateral MCA in 157 cases and bilateral MCA in 38 cases. There are 84 cases in young-aged and middle-aged group and 139 cases in old-aged group. There are 120 cases in the severe stenosis or occlusion group,113 cases in the mild to moderate stenosis group. MRI confirmed infarctions in 176 cases(75.5%). Among the 176 infarction cerebral hemispheres, CWSI in 63(35.8%), LI in 60(34.1%), TI in 32(18.2%), SCI in 21(11.9%), no infraction associated with stenotic MCA in 57 cases(24.5%). There are 26 patients without any risk causes,116 patients with hypertension,61 diabetes patients,53 hyperlipemia patients, morbidity rates are 59.5%,27.2%, and 31%, respectively. The incidence of stroke were significantly greater in patients with hypertension group(81.9%), diabetes mellitus group(80.3%), hyperlipemia group(81.1%), compared with no "three high" group (57.7%).2.compared with the different stenosis group:the incidence of infarction was 84.8% in the severe stenosis and occlusive group, among the infarction cases, CWSI(42.6%), TI(21.8%), LI(21.8%), SCI(13.9%);the incidence of infarction was 66.4% in the mild to middle stenosis group, among the infarction cases, CWSI(26.7%), TI(13.3%), LI(50.7%), SCI(9.3%). The incidence of CWSI, LI and no infarction rate have statistical difference.(χ2 value and are 4.739,15.981,9.9731; P value and are 0.029,0.000,0.002). (1)compared with the different stenosis group in young-aged and middle-aged group:the incidence of infarction was 71.5% in the severe stenosis and occlusive group, among the infarction cases, CWSI(51.5%), TI(24.2%), LI(12.1%), SCI(12.1%); the incidence of infarction was 34.2% in the mild to middle stenosis group, among the infarction cases, CWSI(46.2%),TI(23.1%), LI(23.1%), SCI(7.7%). The no infarction rate has statistical difference.(χ2=11.831; P value=0.001). (2)compared with the different stenosis group in old-aged group: the incidence of infarction was 91.9% in the severe stenosis and occlusive group, among the infarction cases, CWSI(38.2%), TI(20.6%), LI(26.5%), SCI(14.7%); the incidence of infarction was 82.7% in the mild to middle stenosis group, among the infarction cases, CWSI(22.6%), TI(11.3%), LI(56.5%), SCI(9.7%). The incidence of LI has statistical difference. (χ2=12.072; P value=0.001).3.compared with the different age group:the incidence of infarction was 54.8% in the young-aged and middle-aged group, among the infarction cases, CWSI(50.0%), TI(23.9%), LI(15.2%), SCI(10.9%); the incidence of infarction was 87.2% in the old-aged group, among the infarction cases, CWSI(30.8%), TI(16.2%), LI(40.8%), SCI(12.3%). The incidence of CWSI, LI and no infarction rate have statistical difference.(χ2 value and are 5.467,9.873,30.679; P value and are 0.019,0.002, 0.001). (1)compared with the different age group in the severe stenosis or occlusion group:the incidence of infarction was 71.7% in the young-aged and middle-aged group, among the infarction cases, CWSI(51.5%), TI(24.2%), LI(12.1%), SCI(12.1%); the incidence of infarction was 91.9% in the old-aged group among the infarction cases, CWSI(38.2%), TI(20.6%), LI(26.5%), SCI(14.7%). The incidence of LI and no infarction rate have statistical difference.(χ2 value and are 5.828,8.645; P value and are 0.016,0.003). (2)compared with the different age group in the mild to middle stenosis group:the incidence of infarction was34.2% in the young-aged and middle-aged group,, among the infarction cases, CWSI(46.2%), TI(23.1%), LI(23.1%), SCI(7.7%);the incidence of infarction was 90.3% in the old-aged group among the infarction cases, CWSI(22.5%), TI(11.3%), LI(56.5%), SCI(9.7%). The incidence of LI and no infarction rate have statistical difference.(χ2 value and are 4.789,26.532; P value and are 0.029,0.000).Conclusion:1. There are variable lesions patterns in patients with MCA stenosis or occlusion, including CWSI, LI, TI, SCI.2. CWSI might be more common in severe stenosis and occlusive group, the frequency of CWSI was closely correlated with severity of MCA stenosis.3. LI might be more common in old-aged group with mild to moderate stenosis patients.4. In young-aged and middle-aged group, patients with stenosis or occlusion have low infarction rate, the frequency of cerebral infarction was closely correlated with severity of MCA stenosis and age.