血管性认知障碍的脑灌注研究

Cerebral perfusion changes in patients with vascular cognitive impairment

目的探讨血管性认知障碍(VCI)的危险因素,观察VCI患者的脑血流灌注情况。方法选取本院记忆障碍门诊就诊的急性脑梗死患者。所有患者在发病3月后行神经心理学量表评估及头颅MR(包括动态磁敏感对比增强扫描)检查,根据认知评定结果将患者分为认知正常组(对照组)、非痴呆性血管性认知障碍(VCIND)组和血管性痴呆(VaD)组。分析各组基本临床资料及额叶、颞叶、顶叶、丘脑、海马、后扣带回的灌注特点。结果共纳入对照组30例,VCIND组21例,VaD组21例。对照组糖化血红蛋白(HbA1c)水平低于VCIND组及VaD组(P<0.005)。HbA1C是VCI的独立危险因素(P<0.005)。VCIND组右侧额颞叶的平均通过时间(MTT)及右侧后扣带回的达峰时间(TTP)大于对照组(P<0.005),VaD组双侧额叶、右侧颞叶、左侧顶叶、双侧后扣带回的MTT值大于对照组及VCIND组(P<0.005),VaD组双侧海马的MTT及TTP值大于对照组(P<0.005),VaD组左侧颞顶叶、双侧海马的相对脑血流量、相对脑血容量小于对照组(P<0.005)。结论高水平的HbA1C是VCI的独立危险因素。VCI患者存在脑灌注减低,早期以额叶、颞叶及后扣带回的轻度灌注损伤为主,后期损伤程度加重,海马等区域逐渐受累。

Objective To explore the risk factors of vascular cognitive impairment(VCI)and investigate the cerebral perfusion changes in patients with VCI.Methods These patients who were diagnosed with acute ischemic stroke in the memory disorders clinic were enrolled.Patients enrolled performed neuropsychological scale evaluation and cranial MR examination(including dynamic susceptibility contrast enhanced scanning)3 months after the onset of the stroke.According to the scales results,they were divided into normal cognition group(control group),nondementia vascular cognitive impairment(VCIND)group and vascular dementia(VaD)group.The information including clinical data and cerebral perfusion of frontal lobe,temporal lobe,parietal lobe,thalamus,hippocampus and posterior cingulate gyrus was evaluated among the three groups.Results In this study,a total of 30 cases were included in the control group,21 cases in the VCIND group and 21 cases in the VaD group.The level of HbA1 c in the control group was lower than that in VCIND group and VaD group(P<0.005).Glycosylated hemoglobin(HbA1 C)was independent risk factors for VCI(P<0.005).The mean transit time(MTT)value of the right frontal lobe and the right temporal lobe were higher in the VCIND group than those in the control group(P<0.005).The time to peak(TTP)value of the posterior cingulate gyrus was higher in the VCIND group than that in the control group(P<0.005).The MTT value of bilateral frontal lobe,right temporal lobe,left parietal lobe and bilateral posterior cingulate gyrus in VaD group were greater than that in the control group and VCIND group(P<0.005).The TTP and MTTvalue of bilateral hippocampal in VaD group were higher than those in control group(P<0.005).The value of relative cerebral blood flow and relative cerebral blood volume of left temporal lobe,left parietal lobe and bilateral hippocampal were less than those in the control group(P<0.005).Conclusion High level of HbA1 C was a independent risk factor for VCI.Patients with VCI had decreased cerebral perfusion.In the early stage of VCI,mild cerebral hypoperfusion was found in the frontal lobe,temporal lobe and posterior cingulate gyrus.As the disease progressed,the degree of hypoperfusion was serious and other brain regions including hippocampus were injured.