Jauhiainen Anne M, Pihlajamäki Maija, Tervo Susanna, Niskanen Eini, Tanila Heikki, Hänninen Tuomo, Vanninen Ritva L, Soininen Hilkka
Institute of Clinical Medicine, Unit of Neurology, University of Kuopio, Kuopio, Finland.
Hippocampus. 2009 Feb;19(2):166-75. doi: 10.1002/hipo.20494.
We investigated structural and functional changes in the medial temporal lobe (MTL) using magnetic resonance imaging (MRI) and compared the discriminative power of these measures with neuropsychological testing in mild cognitive impairment (MCI) and Alzheimer's disease (AD). Functional MRI (fMRI) was performed in 21 elderly controls, 14 MCI subjects, and 15 mild AD patients during encoding and cued retrieval of word-picture pairs. A region-of-interest-based approach in SPM2 was used to extract the extent of hippocampal activation. The volumes of the hippocampus and entorhinal cortex (EC) were manually outlined from anatomical MR images. Discriminant analyses were conducted to assess the ability of hippocampal fMRI, MTL volumetry, and neuropsychological measures to classify subjects into clinical groups. Entorhinal but not hippocampal volumes differed significantly between the control and MCI subjects. Both entorhinal and hippocampal volumes differed between MCI and AD patients. There were no significant differences in the extent of hippocampal fMRI activation during encoding or retrieval between the groups. Entorhinal volume was the best discriminator with a discriminating accuracy of 85.7% between controls and MCI, 86.2% between MCI and AD, and 97.2% between controls and AD. Delayed recall of a wordlist classified the subjects, second best, with a discriminating accuracy of 81.8% between controls and MCI, 75% between MCI and AD and 93.5% between controls and AD. The accuracy of hippocampal volumetry ranged from 42.9 to 69.4%, and hippocampal fMRI activation during encoding and retrieval had a classification accuracy of only 41.4-57.7% between the groups. Our results suggest that evaluation of entorhinal atrophy, in addition to the prevailing diagnostic criteria, seems promising in the identification of prodromal AD. Future technical improvements may improve the utilization of hippocampal fMRI for early diagnostic purposes.
我们使用磁共振成像（MRI）研究了内侧颞叶（MTL）的结构和功能变化，并将这些测量指标的鉴别能力与轻度认知障碍（MCI）和阿尔茨海默病（AD）患者的神经心理学测试结果进行了比较。对21名老年对照者、14名MCI受试者和15名轻度AD患者在对单词-图片对进行编码和线索回忆期间进行了功能磁共振成像（fMRI）检查。在SPM2中采用基于感兴趣区域的方法来提取海马激活范围。从解剖学磁共振图像上手动勾勒出海马和内嗅皮质（EC）的体积。进行判别分析以评估海马fMRI、MTL容积测量和神经心理学测量指标将受试者分类到临床组的能力。对照者和MCI受试者之间，内嗅皮质而非海马的体积存在显著差异。MCI患者和AD患者之间，内嗅皮质和海马的体积均存在差异。各组之间在编码或回忆期间海马fMRI激活范围无显著差异。内嗅皮质体积是最佳鉴别指标，在对照者和MCI之间的鉴别准确率为85.7%，在MCI和AD之间为86.2%，在对照者和AD之间为97.2%。单词表的延迟回忆对受试者的分类能力次之，在对照者和MCI之间的鉴别准确率为81.8%，在MCI和AD之间为75%，在对照者和AD之间为93.5%。海马容积测量的准确率在42.9%至69.4%之间，编码和回忆期间海马fMRI激活在各组之间的分类准确率仅为41.4% - 57.7%。我们的结果表明，除了现行的诊断标准外，对内嗅皮质萎缩的评估在识别前驱AD方面似乎很有前景。未来的技术改进可能会提高海马fMRI在早期诊断中的应用价值。
