轻度认知障碍及阿尔茨海默病脑葡萄糖代谢改变的统计参数图的PET研究

The Investigation of Fluoro-deoxy-glucose PET in Alzheimer's Disease and Mild Cognitive Impairment Using Statistical Parametric Mapping

目的应用氟脱氧葡萄糖正电子发射计算机断层扫描(18F-FDG PET)探讨阿尔茨海默病(AD)、遗忘型轻度认知障碍(aMCI)患者脑部葡萄糖代谢改变的特点。方法对27例轻度AD患者(AD组)、10例aMCI患者(aMCI组)和21例年龄匹配正常老年志愿者(对照组)行18F-FDG PET成像,对扫描获得的18F-FDG PET图像进行预处理后应用统计参数图(SPM8)对脑葡萄糖代谢进行基于体素水平的组间t检验的统计学分析。结果①与对照组比较,AD组脑葡萄糖代谢减低的脑区包括后扣带回(BA23、31)及楔前叶(BA19)、双侧顶叶(BA40)、双侧颞叶(BA20、21、22、37)、双侧额叶(BA6、9、10)等(P<0.001,未校正,K≥50像素);②AD组与aMCI组比较,脑葡萄糖代谢相对减低的脑区包括后扣带回(BA23、31)及楔前叶(BA19)、颞顶叶(BA40、20、21、22、39)及额叶(BA6、8、9)等(P<0.001,未校正,K≥50体素);③AD组和aMCI组葡萄糖减低的体素数目(12 413个)要少于AD组和对照组的体素数目(17 592个);④aMCI组葡萄糖代谢与对照组比较,仅右侧枕叶的舌回(BA17)减低(P<0.05,未校正)。结论 SPM8可用于诊断和区分AD患者的脑葡萄糖代谢模式。

Aim Voxel-based analysis of the regional cerebral glucose metabolism in patients with Alzheimer＇s disease （AD） and amnestic-type mild cognitive impairment （aMCI） was compared with the normal aging associated with characteristic and progressive reductions by fluorine-18 fluorodeoxyglucose positron emission tomography （18F-FDG PET）. Methods 27 subjects with mild AD patients, 10 aMCI subjects and 21 age-matched normal aging were enrolled. Glucose metabolism differences of brain were assessed by Statistical Parametric Mapping 8 （SPM8） based on the Matlab platform, and compared with the normal aging by using t test. Results Compared with the normal aging group, the AD group had significantly lower brain glucose metabolism in posterior cingulate （BA23, 31）, precuneus （BA19）, bilateral parietal （BA40）, bilateral temporal lobe （BA20, 21, 22, 37） and bilateral frontal cortex （BA6, 9,10） （P〈0.001, uncorrected, K/〉 50 voxels）. Compared with the aMCI group, the AD group had hypometabolism in posterior cingulate （BA23, 31）, precuneus （BA19）, temporal lobe （BA40, 20, 21, 22, 39） and frontal cortex （BA6, 8, 9） （P〈0.001, uncorrected, K ≥ 50 voxels）. Decreased voxels of glucose metabolism between the AD group and the aMCI group （12 413 voxels） were less than those between the AD group and the normal aging group （17 592 voxels）. Compared with the normal aging group, brain glucose metabolism in aMCI group decreased only in the right occipital cortex （BA17） （P〈0.05, uncorrected）. Conclusion Voxel-wise comparison of glucose metabolism in whole brain between the patients and the normal aging can reveal widespread hypometabolism in mild AD.