动态对比增强磁共振对急性脑梗死患者血脑屏障通透性的研究

目的通过动态对比增强(dynamic contrast-enhanced,DCE)MRI定量评估血脑屏障(blood-brain barrier,BBB)的通透性,探讨急性缺血性脑卒中患者BBB通透性的变化及相关影响因素。方法将50例急性缺血性脑卒中患者根据不同治疗方案,分为常规药物组12例,静脉溶栓组19例和取栓组19例,患者在发病72 h内完成DCEMRI(基线时),8例患者发病14 d复查影像检查,发病3个月随访时行改良的Rankin量表(mRS)评分,将mRS评分0~2分为预后良好。使用T1DCE-MRI Extend模型计算BBB通透性指标容积转运常数(Ktrans)值,并计算脑梗死侧与脑梗死对侧Ktrans值的比值(Ki/c)。比较所有患者脑梗死侧与脑梗死对侧、发病14 d复查与基线时、3组Ktrans值和Ki/c值差异,用多因素线性回归分析lg(Ki/c)值的相关影响因素。结果所有患者脑梗死侧Ktrans值较脑梗死对侧明显增高0.0047(0.0019,0.0087)/min vs 0.0011(0.0003,0.0016)/min,P=0.000];发病14 d复查Ki/c值较基线时明显增高70.77(13.43,399.43)vs 5.31(3.58,12.64),P=0.012]。常规药物组lg(Ki/c)值为0.42±0.49,静脉溶栓组lg(Ki/c)值为0.77±0.32,取栓组lg(Ki/c)值为0.85±0.41,静脉溶栓组和取栓组lg(Ki/c)值较常规药物组明显升高(P=0.021,P=0.005),静脉溶栓组与取栓组lg(Ki/c)值比较,差异无统计学意义(P=0.534)。常规药物组、静脉溶栓组和取栓组发病3个月预后良好比例比较,差异无统计学意义(66.7%vs 52.6%vs 52.6%,P=0.695)。多因素线性回归分析显示,lg(Ki/c)值与治疗方案(P=0.017)和脑梗死病史(P=0.030)有关。结论急性缺血性脑卒中患者BBB通透性与不同治疗方法、既往脑梗死病史有关,并且发病14 d BBB通透性较72 h内明显增高。

Role of dynamic contrast-enhanced MRI in assessing permeability of blood brain barrier in acute ischemic stroke patients

Objective To study the permeability of blood brain barrier(BBB)in acute ischemic stroke(AIS)patients and its relevant factors according to its quantitative assessment by dynamic contrast-enhanced(DCE)MRI.Methods Fifty AIS patients were divided into conventional drug treatment group(n=12),intravenous thrombolysis group(n=19)and thrombectomy group(n=19).They underwent DCE MRI within 72 h after symptomonset.Of the 50 AIS patients,8 underwent DCE MRI again on day 14 after symptomonset.The patients were followed up for 3 months,during which their mRS score was recorded.The outcome of the patients with a mRS score of 0-2 was assessed as good.The volume transport constant Ktrans value of BBB permeability was calculated according to the T1DCE MRI extend model.The ratio of Ktrans value on cerebral infarction side and collateral cerebral infarction side(Ki/c)was recorded.The difference of Ktrans value and Ki/c value in cerebral infarction side and collateral cerebral infarction side was compared on day 14 after admission and at baseline time in 3 groups.The factors related with lg(Ki/c)value were analyzed by multivariate linear logistic regression analysis.Results The Ktrans value of cerebral infarction side was significantly higher than that of collateral cerebral infarction side in AIS patients0.0047(0.0019,0.0087)/min vs 0.0011(0.0003,0.0016)/min,P=0.000].The Ki/c value on day 14 after symptomonset was significantly higher than that at baseline time70.77(13.43,399.43)vs 5.31(3.58,12.64),P=0.012].The lg(Ki/c)value of conventional drug treatment group,intravenous thrombolysis group and thrombectomy group was 0.42±0.49,0.77±0.32 and 0.85±0.41 respectively.The lg(Ki/c)value was significantly higher in intravenous thrombolysis group and thrombectomy group than in conventional drug treatment group(P=0.021,P=0.005).No significant difference was detected in lg(Ki/c)value between intravenous thrombolysis group and thrombectomy group(P=0.534)and in good outcome rate at month 3 after symptomonset in 3 groups(66.7%vs 52.6%vs 52.6%,P=0.695).Multivariate linear logistic regression analysis showed that the lg(Ki/c)value was related with the treatment plan and cerebral infarction history(P=0.017,P=0.030).Conclusion The permeability of BBB is related with the treatment plan and cerebral infarction history,and is significantly higher on day 14 after symptomonset than within 72 h after symptomonset in AIS patients.