摘要
目的:对轻度阿尔茨海默病(AD)患者皮层下灰质结构进行自动分割,研究这些灰质结构体积萎缩特点、其与患者总体认知功能损害的关系,及其在疾病诊断中的应用价值。方法:选取29例轻度AD患者和30名正常老年人(正常对照组),对全脑进行1.5T磁共振快速扰相位梯度回波翻转恢复脉冲序列扫描。采用FSL软件的FIRST工具对被试者3D T1图像内皮层下灰质结构(包括海马、杏仁核、伏隔核、尾状核、壳核、苍白球、丘脑)进行精确分割后,两组之间各个灰质结构相对体积均值(灰质结构体积/颅内总体积×100)进行双样本t检验,患者组各灰质结构相对体积与简易智能精神状态检查量表(MMSE)评分的相关性进行偏相关分析,最后采用二项逻辑回归分析与受试者工作特征(ROC)曲线研究这些灰质结构相对体积在诊断轻度AD中的意义。结果:与正常对照组比较,轻度AD组左侧海马、右侧杏仁核、双侧丘脑、右侧尾状核、左侧壳核、双侧苍白球相对体积有显著性缩小;轻度AD组左侧海马、壳核、丘脑及右侧杏仁核的相对体积与MMSE评分具有相关性;二项逻辑回归分析最终进入模型的协变量为年龄与左侧海马相对体积,准确率为86.3%,ROC曲线示曲线下面积(AUC)为0.897,设定约登指数(敏感度+特异度-1)最大值的点为诊断点,该点的敏感度为83.3%,特异度为96.3%。结论:除了海马以外,轻度AD患者其他皮层下灰质结构也出现了萎缩,其中右侧杏仁核、左侧壳核与左侧丘脑的萎缩可能参与了患者认知功能损害的病理机制。在这些灰质结构中,海马最具有诊断意义。
Objective： To evaluate the atrophy pattern of subcortical gray matter structures in patients with mild Alzheimer＇s disease（AD） by using an automatic segmentation tool. These structures include hippocampi, amygdalae, accumbens, caudates, putamen, pallidum, thalami. Methods： Twenty-nine cases of mild AD and 30 normal aging volunteers as control subjects were scanned with 3D FSPGRIR sequence using 1.5T MR system. The subcortical gray matter structures were seg- mented using FIRST tool in FSL. The mean values of each structure＇s relative volume（gray matter volume/intracranial volumex 100） were compared with 2-sample t test. The correlation between the relative volume of each structure and MMSE scores were evaluated using partial correlation analysis. Binary logistic diagnostic significance of the relative volume of each structure. regression analysis and ROC curve were applied to assess the Results： Compared with normal control group, the relative vol- ume of left hippocampus, right amygdala, bilateral thalami, right caudate, left putamen and bilateral pallidum in mild AD group was significantly smaller than that in the control group（P〈0.05）. The relative volume of left hippocampus, right amygdala, left thalamus and left putamen was correlated with MMSE scores. It was the relative volume of left hippocampus that entered the final model of binary logistic regression analysis. The accuracy was 86.3%. The area under the curve of ROC curve was 0.897. In the cut-off point, i.e. maximal value of Yuden index, the sensitivity was 83.3% and the specificity was 96.3%. Conclusion： In addition to hippoeampus, volumetric atrophy was found in other subcortical gray matter structures in mild AD. The atrophy of right amygdala, left putamen and left thalamus may take part in the pathological mechanism of cognitive impairment in AD patients. Among these structures, hippocampus is of the most diagnostic significance.
出处
《中国临床医学影像杂志》
CAS
2012年第10期688-691,共4页
Journal of China Clinic Medical Imaging
基金
宁波市社会发展科研项目(项目编号2011C50012)
关键词
阿尔茨海默病
磁共振成像
Alzheime
disease
Magnetic resonance imaging
