后部皮质萎缩患者脑部葡萄糖代谢特征及其与认知功能的相关性分析

Characteristics of Brain Glucose Metabolism and Its Correlation with Cognitive Function in Patients with Posterior Cortical Atrophy

目的利用^(18)F-脱氧葡萄糖(^(18)F-FDG)正电子发射断层(PET)显像分析后部皮质萎缩(PCA)患者脑部葡萄糖代谢特点及其与认知评分相关性。方法12例临床诊断为PCA的患者和20例年龄、性别匹配的健康对照者行静息状态下脑^(18)F-FDG PET成像,运用统计参数图(SPM)两样本t检验比较两组的PET图像在体素水平的差异,获得PCA患者脑葡萄糖代谢异常脑区并分析其与认知量表评分的相关性。结果SPM分析显示,与健康对照组比较,PCA患者双侧顶叶(包括楔前叶、角回)、颞中回的葡萄糖代谢降低,基底节区、额叶、小脑的葡萄糖代谢相对增高。楔前叶局部葡萄糖代谢率与视空间觉、记忆、Gerstmann’s综合征相关测验评分呈正相关(R=0.3982~0.8229,P<0.05);角回局部葡萄糖代谢率与记忆、执行功能相关测试评分呈正相关(R=0.5949~0.7317,P<0.05)。结论脑^(18)F-FDG PET显像可应用于PCA的临床诊断及疾病严重度评估。

Aim To analyze the characteristics of cerebral glucose metabolism and its correlation with cognitive scores in patients with posterior cortical atrophy(PCA)by^(18)F-fluorodeoxyglucose(^(18)F-FDG)positron emission tomography(PET).Methods Twelve patients with PCA and 20 age-and sex-matched healthy controls underwent^(18)F-FDG PET brain imaging in resting state.The two sample t test of statistical parameter map(SPM)was used to compare the PET images between the two groups on voxel-wise level.The brain regions with abnormal glucose metabolism in PCA patients were obtained and their correlations with cognitive scores were analyzed.Results SPM analysis showed that the glucose metabolism of bilateral parietal lobe(including precuneus and angular gyrus)and middle temporal gyrus was decreased,while that of basal ganglia,frontal lobe and cerebellum was relatively increased in PCA patients compared with the healthy controls.There was a positive correlation between the local glucose metabolic rate of precuneus and the scores of visual spatial perception,memory and Gerstmann’s syndrome tests(R=0.3982~0.8229,P<0.05).The local glucose metabolic rate of angular gyrus was positively correlated with the scores of memory and executive function tests(R=0.5949~0.7317,P<0.05).Conclusion^(18)F-FDG PET brain imaging can be used for diagnosis and severity assessment of PCA.