阿尔茨海默病患者认知功能与相关脑区血流量的关系

Association between the severity of cognitive dysfunction in Alzheimer's disease and cerebral blood flow in the frontal lobe, temporal lobe, basal ganglia and hippocampus

目的探讨不同程度阿尔茨海默病(Alzheimer disease,AD)患者额、颞、基底节、海马区CT血流灌注水平及其与认知功能损害的相关性。方法随机选择60例AD患者及30名健康老人,用简易智能状态量表(Mini-Mental State Exam,MMSE)及韦氏记忆量表(Wechsler Memory Scale,WMS)进行认知功能检查,并选取海马区层面进行CT血流灌注扫描,获得感兴趣区的血流灌注值。采用临床痴呆量表将AD组分为轻、中、重度痴呆3组。结果轻、中、重度AD组与健康组MMSE总分、长时、短时及瞬时记忆测验量表分比较的差异均有统计学意义。比较4组患者的双侧额、颞、基底节、海马区血流灌注参数,发现右额叶、右颞叶及左基底节脑血容量(cerebral blood volume,CBV)的差异有统计学意义,中度AD组较轻度组、对照组CBV明显升高;重度AD组与各组比较均无统计学差异。逐步回归分析显示认知功能与左海马、右基底节CBV呈显著正相关。结论 AD患者局部脑区的CBV变化,反映了不同程度痴呆患者的大脑认知储备能力。

Background：The degree of cognitive dysfunction in Alzheimer＇s disease （AD） may be related to region-specific alterations in cerebral blood flow.Methods： Sixty patients with AD randomly selected from a psychiatric outpatient department and 30 randomly selected healthy elderly community controls were administered the Mini-Mental State Exam （MMSE） and the Wechsler Memory Scale （WMS）. The AD subjects were classified as mild, moderate or severe based on the results of the Clinical Dementia Rating scale. All subjects underwent a perfusion CT scan to assess blood perfusion in brain regions of interest. Results：There were significant differences between the three AD groups and the normal controls in the mean MMSE scores and in the scores for long-term memory, short-term memory and immediate memory. The cerebral blood volume in the four groups of subjects were significantly different in the right frontal lobe, right temporal lobe, and left basal ganglia. The cerebral blood volume was significantly higher in the moderately demented group than in the mildly demented group and the control group. The cerebral blood volume in the severely demented group was not statistically different from that in the other three groups. Stepwise multiple regression identified a positive correlation between cognitive functioning and the cerebral blood volume in the left hippocampus and in the right basal ganglia. Conclusions：Changes in the cerebral blood volume in different regions of the brain are associated with the severity of the cognitive dysfunction in AD.