Ultrastructural hippocampal and white matter alterations in mild cognitive impairment:: A diffusion tensor imaging study
Ultrastructural hippocampal and white matter alterations in mild cognitive impairment:: A diffusion tensor imaging study
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DOI：
10.1159/000077817
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发表时间：
2004-01-01
影响因子：
2.4
通讯作者：
Stoeter, P
中科院分区：
文献类型：
--
作者：
Fellgiebel, A;Wille, P;Stoeter, P
轻度认知障碍（MCI）被认为是正常衰老和痴呆之间的过渡阶段。在阿尔茨海默病（AD）中，白色物质结构病理是由于沃勒变性和中央血管病。然而，在MCI患者中，白色改变的存在和程度作为记忆功能受损的可能相关性和作为随后进展为AD的预测因子尚未阐明。扩散张量成像（DTI）显示大脑白色物质束的超微结构完整性。因此，它可以检测改变MCI患者组织完整性的病理过程。在我们的前瞻性研究中，常规和扩散张量磁共振扫描获得了14例MCI患者，19例AD患者和10名健康对照。在颞叶、额叶、顶叶和枕叶白色物质区域以及胼胝体（胼胝体和压部）和海马中测量平均扩散率（MD）和各向异性分数（FA）。与对照组相比，MCI患者在左侧半卵圆中心（p = 0.013;右侧：p = 0.026）、左侧颞叶（p = 0.006）、右侧颞叶（p = 0.014）和左侧海马（p = 0.002）区域显示出更高的MD值。MCI患者和对照组的FA值在任何区域均无显著差异。与对照组相比，AD患者在左半卵圆中心（p = 0.012）、左顶叶（p = 0.001）、右顶叶（p = 0.028）、左颞叶（p = 0.018）、右颞叶（p = 0.011）和左海马区（p = 0.002）的MD值增加。与对照组相比，AD患者左侧颞区（p = 0.017）和左侧海马（p = 0.031）的FA值降低。AD和MCI患者的FA和MD值无显著差异。升高的MD值表明MCI患者的脑组织改变，发现在通常涉及早期变化，由于AD的区域，特别是左海马。区分MCI患者与对照组的敏感性为71.4%（特异性设定为80%）。因此，DTI技术验证了MCI的概念，并且扩散张量MR测量可以是量化活体MCI病理的有用工具。版权所有（C）2004 S. Karger AG，巴塞尔。
Mild cognitive impairment (MCI) is considered to be a transitional stage between normal aging and dementia. In Alzheimer's disease ( AD), white matter structural pathology is due to Wallerian degeneration and central angiopathy. However, in MCI patients, the presence and extent of white matter alterations as a possible correlate of impaired memory function and as predictor of subsequent progression to AD is not clarified yet. Diffusion tensor imaging (DTI) reveals the ultrastructural integrity of cerebral white matter tracts. Therefore, it could detect pathological processes that modify tissue integrity in patients with MCI. In our prospective study, conventional and diffusion tensor MR scans were obtained from 14 patients with MCI, 19 patients with AD, and 10 healthy controls. Mean diffusivity (MD) and fractional anisotropy ( FA) were measured in temporal, frontal, parietal and occipital white matter regions as well as in the corpus callosum ( genu and splenium) and the hippocampus. MCI patients showed higher MD values in the left centrum semiovale (p = 0.013; right: p = 0.026), in the left temporal (p = 0.006), the right temporal (p = 0.014) and the left hippocampal (p = 0.002) region as compared to the control group. FA values of MCI patients and controls did not differ significantly in any region. Compared to controls, AD patients had increased MD values in the left centrum semiovale (p = 0.012), the left parietal (p = 0.001), the right parietal (p = 0.028), the left temporal (p = 0.018), the right temporal (p = 0.011) and the left hippocampal region ( p = 0.002). Decreased FA values were measured in the left temporal area (p = 0.017) and in the left hippocampus (p = 0.031) in AD patients compared to controls. FA and MD values did not differ significantly between AD and MCI patients. Elevated MD values indicating brain tissue alterations in MCI patients were found in regions that are typically involved in early changes due to AD, particularly the left hippocampus. The sensitivity of distinguishing MCI patients from controls was 71.4% (with a specificity set at 80%). Therefore, the DTI technique validates the MCI concept, and diffusion tensor MR measurement can be a helpful tool to quantify MCI pathology in vivo. Copyright (C) 2004 S. Karger AG, Basel.