海马萎缩是缺氧性失忆症患者大脑的关键变化。
Hippocampal atrophy is the critical brain change in patients with hypoxic amnesia.
作者信息
Di Paola M, Caltagirone C, Fadda L, Sabatini U, Serra L, Carlesimo G A
机构信息
Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Via Ardeatina 306, Rome, Italy.
出版信息
Hippocampus. 2008;18(7):719-28. doi: 10.1002/hipo.20432.
Anoxia is considered a good model for studying amnesia. However, not all individuals who experience anoxic events develop memory problems. Moreover, the question still remains about whether, after anoxia, damage is limited to the hippocampus in patients with amnesia and without other significant cognitive deficits. Here we investigated brain damage in a selected sample of adults affected exclusively by an amnesic syndrome after an anoxic episode. The cerebral MR images of these patients were submitted to visual inspection, volumetric measurements of the mesial temporal structures following manual segmentation, and to Voxel-Based Morphometry of the whole brain. We studied five anoxic patients and thirty-three well-matched healthy subjects. Our aim was to: (a) quantify regional atrophic changes associated with chronic anoxic damage compared to control subjects (Group Comparison Analysis); (b) identify regions of common abnormality across all patients (Conjunction Analysis in the VBM); (c) investigate whether measures of regional volume reduction correlated with neuropsychological memory scores; (d) compare the results obtained with visual inspection and ROI analyses with those obtained with VBM. We found that anoxic patients presented a significant reduction of gray matter volume in the hippocampus bilaterally compared to healthy subjects. The only common atrophic region across all patients was the hippocampus bilaterally. Correlation analysis showed only a trend between the Prose immediate free recall test and the left hippocampus. Our findings confirm that the hippocampus is very sensitive to damage stemming from anoxia. Patients with hypoxic amnesia may present damage in other brain regions, but only hippocampal atrophy is common in all of them.
缺氧被认为是研究失忆症的一个良好模型。然而,并非所有经历缺氧事件的个体都会出现记忆问题。此外,对于失忆症患者且无其他明显认知缺陷的人,在缺氧后损伤是否仅限于海马体这一问题仍然存在。在此,我们调查了一组仅受缺氧发作后失忆综合征影响的成年人样本中的脑损伤情况。这些患者的脑部磁共振图像接受了目视检查、手动分割后对内侧颞叶结构的体积测量以及全脑基于体素的形态计量学分析。我们研究了5名缺氧患者和33名匹配良好的健康受试者。我们的目的是:(a) 与对照受试者相比,量化与慢性缺氧损伤相关的区域萎缩变化(组间比较分析);(b) 识别所有患者中共同的异常区域(基于体素的形态计量学中的联合分析);(c) 研究区域体积减少的测量值是否与神经心理学记忆评分相关;(d) 将目视检查和感兴趣区域分析获得的结果与基于体素的形态计量学分析获得的结果进行比较。我们发现,与健康受试者相比,缺氧患者双侧海马体灰质体积显著减少。所有患者唯一共同的萎缩区域是双侧海马体。相关性分析仅显示散文即时自由回忆测试与左侧海马体之间存在一种趋势。我们的研究结果证实,海马体对缺氧引起的损伤非常敏感。缺氧性失忆症患者可能在其他脑区出现损伤,但只有海马体萎缩在所有患者中都很常见。