Galton C J, Patterson K, Graham K, Lambon-Ralph M A, Williams G, Antoun N, Sahakian B J, Hodges J R
University Neurology Unit, Addenbrooke's Hospital, Cambridge, UK.
Neurology. 2001 Jul 24;57(2):216-25. doi: 10.1212/wnl.57.2.216.
To characterize and quantify the patterns of temporal lobe atrophy in AD vs semantic dementia and to relate the findings to the cognitive profiles. Medial temporal lobe atrophy is well described in AD. In temporal variant frontotemporal dementia (semantic dementia), clinical studies suggest polar and inferolateral temporal atrophy with hippocampal sparing, but quantification is largely lacking.
A volumetric method for quantifying multiple temporal structures was applied to 26 patients with probable AD, 18 patients with semantic dementia, and 21 matched control subjects.
The authors confirmed the expected bilateral hippocampal atrophy in AD relative to controls, with involvement of the amygdala bilaterally and the right parahippocampal gyrus. Contrary to expectations, patients with semantic dementia had asymmetric hippocampal atrophy, more extensive than AD on the left. As predicted, the semantic dementia group showed more severe involvement of the temporal pole bilaterally and the left amygdala, parahippocampal gyrus (including the entorhinal cortex), fusiform gyrus, and the inferior and middle temporal gyri. Performance on semantic association tasks correlated with the size of the left fusiform gyrus, whereas naming appeared to depend upon a wider left temporal network. Episodic memory measures, with the exception of recognition memory for faces, did not correlate with temporal measures.
Hippocampal atrophy is not specific for AD but is also seen in semantic dementia. Distinguishing the patients with semantic dementia was the severe global but asymmetric (left > right) atrophy of the amygdala, temporal pole, and fusiform and inferolateral temporal gyri. These findings have implications for diagnosis and understanding of the cognitive deficits in AD and semantic dementia.
描述并量化阿尔茨海默病（AD）与语义性痴呆患者颞叶萎缩的模式，并将研究结果与认知特征相关联。内侧颞叶萎缩在AD中已有充分描述。在颞叶变异型额颞叶痴呆（语义性痴呆）中，临床研究提示颞极和颞下外侧萎缩，海马得以保留，但在很大程度上缺乏量化研究。
采用一种体积测量方法对26例可能患有AD的患者、18例语义性痴呆患者以及21例匹配的对照受试者的多个颞叶结构进行量化。
作者证实了AD患者相对于对照组预期的双侧海马萎缩，双侧杏仁核及右侧海马旁回也有受累。与预期相反，语义性痴呆患者存在不对称的海马萎缩，左侧比AD更广泛。正如所预测的，语义性痴呆组双侧颞极以及左侧杏仁核、海马旁回（包括内嗅皮质）、梭状回以及颞下回和颞中回受累更严重。语义联想任务的表现与左侧梭状回的大小相关，而命名似乎取决于更广泛的左侧颞叶网络。除了对面孔的识别记忆外，情景记忆测量与颞叶测量结果无相关性。
海马萎缩并非AD所特有，在语义性痴呆中也可见到。区分语义性痴呆患者的是杏仁核、颞极以及梭状回和颞下外侧回严重的整体但不对称（左侧>右侧）萎缩。这些发现对AD和语义性痴呆的诊断及认知缺陷的理解具有重要意义。
