MAPPING LOCAL STRUCTURAL HIPPOCAMPAL CHANGES IN ALZHEIMER?S DISEASE

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 “在3T磁共振成像上绘制阿尔茨海默病和正常衰老的局部海马区结构变化” 背景：一些研究表明，随着年龄的增长，海马体体积显著减少。准确描述体内典型的与年龄相关的海马区变化是非常重要的，因为阿尔茨海默病的早期阶段也与海马体体积的丧失有关。 目的：应用3T高分辨率磁共振(MR)图像的放射状萎缩标测(RAM)研究老年及中、重度阿尔茨海默病(AD)患者海马区局部改变。 方法：研究方法。14例AD患者(年龄75±5岁，男性3例，简易智力状态检查13±4岁)和14名对照组(年龄71±5岁，男性9例，简易智力状态检查29±1)在3.0T扫描仪上进行高分辨率磁共振成像。采用手工示踪法分离大鼠海马区。RAM允许通过使用三维参数表面网格模型平均受试者的海马体形状来评估组的差异和相关性。绘制了百分比差值、皮尔逊相关系数和显著性三维图。 结果：在老年健康对照组中，海马体体积与年龄呈负相关(右侧和左侧的r.53和.56，p&lt；0.05，相当于从65岁开始每10岁老年人的海马体体积减少17%)。与衰老相关的萎缩被定位到尾部和身体对应于CA1亚区的背侧和外侧区域，以及对应于下丘脑区的头部腹侧区域。随着年龄的增长，脑体积显著增加，主要定位于与CA1亚区相对应的双侧头部背侧受限区域。 AD患者右侧和左侧的体积分别缩小37%和30%(p&lt；.0005)。AD相关性萎缩被映射到与年龄相关的身体和尾部区域，以及与CA1亚区对应的头部背侧区域，不受年龄的影响。与CA2-3区域相对应的区域在老龄化和AD中都相对幸免。 结论：AD患者的海马区萎缩映射到身体和尾部的区域，部分重叠于受正常衰老影响的区域。阿尔茨海默病患者大脑前、背侧CA1亚区的特定区域MAP与正常衰老无关。 这种差异可能与两种情况下涉及的不同系统有关，也可能与AD的临床症状有关。在衰老过程中幸免于难的海马区前部可能是阿尔茨海默病的专属区域。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. "Mapping local structural hippocampal changes in Alzheimer's disease and normal aging on MR imaging at 3T" Background: Some studies have shown significant hippocampal volume loss with increasing age. An accurate characterization of the typical age-related hippocampal changes in vivo is very important because Alzheimer's disease in the early stages is also associated with hippocampal volume loss. Objective: To study local hippocampal changes in aging and moderate to severe Alzheimer's patients disease with radial atrophy mapping (RAM) based on high resolution magnetic resonance (MR) images at 3 Tesla. Methods. 3D high resolution T1-weighted magnetic resonance (MR) were acquired on a 3.0 T scanner from 14 AD (age 75¿5 years, 3 males, Mini Mental State Examination 13¿4) and 14 controls (age 71¿5 years 9 males, Mini-Mental State Examination 29¿1). The hippocampal formation was isolated by manual tracing. RAM allows to assess group differences and correlations by averaging hippocampal shapes across subjects using 3-dimensional parametric surface mesh models. Percentage difference, Pearson's r, and significance 3-dimensional maps were produced. Results: Hippocampal volumes were inversely correlated with age in older healthy controls (r .53 and .56 to the right and left, p< 0,05, corresponding to 17% lower volume for every 10 years of older age from age 65). Aging-associated atrophy mapped to dorsal and lateral areas of the tail and body corresponding to the CA1 subfield and to ventral areas of the head corresponding to the subiculum. Significantly increased volume with older age mainly mapped to restricted dorsal areas of the head bilaterally corresponding to the CA1 subfield. Volumes were 37% and 30% smaller in AD patients to the right and left (p<.0005). AD-associated atrophy mapped to areas of the body and tail corresponding to those also associated with age, and dorsal areas of the head corresponding to the CA1 subfield unaffected by age. Regions corresponding to the CA2-3 fields were relatively spared in both aging and AD. Conclusions: Hippocampal atrophy in AD maps to areas in the body and in the tail partly overlapping to those affected by normal aging. Specific areas map to the anterior and dorsal CA1 subfield involved in AD were not involved in normal aging. Such differences might relate to the different systems involved in two conditions and to the clinical syndromes of AD. The anterior hippocampal areas spared in aging might be specific to Alzheimer's disease.