George A E, de Leon M J, Stylopoulos L A, Miller J, Kluger A, Smith G, Miller D C
Department of Radiology (Neuroradiology), New York University School of Medicine, NY 10016.
AJNR Am J Neuroradiol. 1990 Jan-Feb;11(1):101-7.
Neuropathologic changes in the temporal lobe, including focal atrophy of the subiculum and entorhinal cortex, have been described in association with Alzheimer disease. We studied the usefulness of detecting temporal-lobe structural changes on CT in making the diagnosis of Alzheimer disease. The dementia imaging protocol we use includes thin-section (5 mm) cuts of the temporal lobe oriented 20 degrees negative (caudal) to the plane of the canthomeatal line. Thirty-four patients with suspected Alzheimer disease and 20 normal elderly control subjects, all between 65 and 80 years old, were studied with a standard protocol that also included neurologic and medical examinations and detailed psychometric testing. All the temporal-lobe evaluations of the five variables measured were significantly associated with the presence or absence of Alzheimer disease. Almost all Alzheimer patients showed evidence of mild or greater severity of overall temporal-lobe atrophy. The absence of temporal-lobe atrophy, seen in approximately one half the normal cases, identified normal individuals with a high degree of specificity (95%). The presence of characteristic hippocampal lucency, apparently due to enlargement of the choroid and hippocampal fissures, showed the highest sensitivity and classification accuracy of all the variables tested (82 and 80% respectively; p less than .001), correctly identifying 82% of Alzheimer patients and 80% of Alzheimer patients and control subjects. These results indicate that CT detection of structural changes in the temporal lobe and hippocampus strongly support the diagnosis of Alzheimer disease. A temporal-lobe imaging protocol for CT, and by extension for MR, is suggested for the evaluation of patients with the clinical diagnosis of a dementing disorder.
颞叶的神经病理变化，包括海马旁回和内嗅皮质的局灶性萎缩，已被描述与阿尔茨海默病相关。我们研究了CT检测颞叶结构变化在阿尔茨海默病诊断中的作用。我们使用的痴呆症成像方案包括对颞叶进行薄层（5毫米）扫描，扫描方向与眦耳线平面呈20度负角（尾侧）。对34名疑似阿尔茨海默病患者和20名年龄在65至80岁之间的正常老年对照者进行了研究，采用的标准方案还包括神经学和医学检查以及详细的心理测量测试。所测量的五个变量的所有颞叶评估结果均与阿尔茨海默病的存在与否显著相关。几乎所有阿尔茨海默病患者都显示出总体颞叶萎缩程度为轻度或更严重的证据。在大约一半的正常病例中可见颞叶无萎缩，这对正常个体具有高度特异性（95%）。特征性海马透亮的出现，显然是由于脉络丛和海马裂增宽所致，在所测试的所有变量中显示出最高的敏感性和分类准确性（分别为82%和80%；p<0.001），正确识别出82%的阿尔茨海默病患者以及80%的阿尔茨海默病患者和对照者。这些结果表明，CT检测颞叶和海马的结构变化有力地支持了阿尔茨海默病的诊断。建议采用颞叶成像方案进行CT检查，进而也可用于MR检查，以评估临床诊断为痴呆症的患者。
