轻度血管性认知障碍患者计算能力的功能MRI研究

目的 利用功能MRI (fMRI)探讨轻度血管性认知障碍(MVCI)患者与正常老年人计算能力的差异,为MVCI患者的诊断提供依据.材料与方法对22例MVCI 患者与12例正常老年人进行20以内减法计算时的fMRI,用SPM5处理得出脑激活图,比较正常老年人组和患者组的脑区激活情况和额、顶叶偏侧化现象,用两个独立样本t 检验和Mann-Whitney检验比较两组的反应时间和正确率.结果 患者的正确率明显低于正常老年组(χ2=18.6,P <0.001),反应时间明显延长(t =3.676,P <0.05).患者在双侧的顶上、下小叶(顶下小叶为主),双侧额中回、双侧海马、海马旁回、右侧扣带回后部、

Calculation ability in mild vascular cognitive impairment and normal aging:a functional magnetic resonance imaging study

Objective： To explore the difference of arithmetic calculation between the normal elders with non cognitive impairment and the patients with mild vascular cognitive impairment （MVCI） by functional magnetic resonance imaging （fMRI）. Materials and Methods： Twenty-two patients with vascular cognitive impairment and 12 non-cognitive-disable elders were scanned by M RI when they perfonned calculation. Comparing the normal cognitive patients with MVCI group in situation of activated voxels by subtraction within 20 and in the laterality of fimctional areas in frontal lobe and parietal lobe by subtraction, as well as comparing the reaction time and accuracy by through behavior data. Results： During the subtraction task, the behavior data showed that accuracy rate in MVCI group was lower than normal one （X^2= 18.6, P〈0.001） and the reaction time in MVCI group was longer than the normal group （r=3.676, P〈0.05）. Compared to the normal group, the MVCI group exhibited hypo-activity in bilateral parietal lobe （inferior parietal lobule mainly）, bilateral middle frontal gyms, bilateral hippocampus, parahippocampal gyms, right posterior cingulate gyms, bilateral middle temporal gyms, lelt inferior temporal gyrus, bilateral occipital and bilateral cerebellar （P〈0.005）. In subtraction, for both right handed groups, activation of functional areas of frontal and parietal lobe had the left lateraiity. In nomal group, the laterality index of parietal lobe was higher than that of fi＇ontal lobe, while in MVCI group it was on the contrary. Conclusion： The patients with MVCI has an insufficient in calculation ability and somehow compensation. The study of the calculation IMRI can offer a powerful reference for the diagnosis of MVCI.