基于体素的形态测量学在阿尔茨海默病和轻度认知障碍中的应用价值

目的：应用基于体素的形态测量学（VBM）方法比较阿尔茨海默病（AD）和轻度认知障碍（MCI）患者和健康老年人灰质体积的不同，探讨VBM方法在AD、MCI诊断中的应用价值。方法：本研究包括10例AD患者（AD组）、9例MCI患者（MCI组）、10例老年健康志愿者（健康对照组），检查系列包括头常规轴面T2WI、T1WI、轴面FLAIR、矢状面T1WI，全脑3D-SPGR。应用VBM方法处理数据，把脑组织分割成灰质、白质和脑脊液，最后应用两样本t检验两两比较灰质体积改变。结果：AD组与正常对照组脑灰质体积比较：AD组大脑皮层灰质体积弥漫减少，激活区域几乎分布整个大脑半球，以两侧内侧颞叶（海马、梨状皮层、内嗅皮层）为著。右侧海马减少的体素总数为2358个，左侧海马减少的体素总数为2967个，前后扣带回体素明显减少；MCI组与正常对照组比较：MCI组灰质减少的区域依然较多，但与AD和对照组相比，激活区域明显减少。其中最明显的是内侧颞叶内嗅皮层、海马旁回区域，右侧体素减少总数为1368，左侧1135；MCI组和AD组的比较：MCI组较AD组灰质减少的区域更多，内侧颞叶和海马区域基本没有激活区域，较明显的激活区域位于双侧额顶颞叶、扣带回。双侧尾状核头部和左侧丘脑亦有较明显激活，而豆状核没有明显激活。结论：内侧颞叶和海马体积减小是评价AD和MCI最敏感的区域，VBM可以有效评价灰质体积的改变。

Preliminary Study of the Clinical Value of Voxel-based Morphometry Technique in Alzheimer′s Disease and Mild Cognition Impairment

Objective：Using voxel based morphometry （VBM） technique to compare the differences of grey matter volume in Alzheimer＇s disease （AD）,mild cognition impairment （MCI） and normal healthy aged volunteers and to evaluate the clinical value of VBM in the diagnosis of AD and MCI. Methods： 10 AD patients,9 MCI patients and 10 volunteers were included in the study. MRI with routine axial T1WI, T1WI, FLAIR; sagittal plane T1 WI sequences and whole brain 3DSPGR images were performed. All data were studied by VBM technique, the brain was segmented to grey matter, white matter and cerebral spinal fluid （CSF）,lastly t test was used to compare the grey matter volume of every two groups in this study. Results：Comparison of AD and normal aged volunteers, the grey matter volume of AD was much less than that of normal volunteers, the activated area distributed in almost the whole hemisphere cortex, especially the medial temporal lobe （hippocampus,pyriform cortex,internal olfactory cortex）. The total voxel number reduced in the right hippocampus were 2358 and in the left were 2967,the voxel number in anterior and posterior of gyri cinguli were markedly reduced too. Comparison of MCI and normal groups, the reduction area of grey matter was still obvious, but compared with that of AD, the activated areas were markedly lesser,especially the internal olfactory cortex of medial temparal lobe and pare-hippoeampus gyri area. The total reduction voxel numbers in the right were 1368 and in the left were 1135. Comparison of AD and MCI patients, the reduction area of grey matter in MCI were more than that of AD, basically there was no activated area in hippo- campus and medial temporal lobe. The more obviously activated regions located at bilateral frontal, parietal and temporal lobes and gyri cinguli. There were relatively obviously activated regions in bilateral caudate nucleus head and left thalamus, yet no obvious activation was assessed in nucleus lentiformis. Conclusion： Reduction of the volume of medial temporal lobe and hippocampus is the most sensitive approach in the evaluation of AD and MCI. VBM is a valuable technique to evaluate the change of grey matter volume.