Waldemar G
Department of Neurology, Rigshospitalet, Copenhagen, Denmark.
Cerebrovasc Brain Metab Rev. 1995 Summer;7(2):89-130.
New developments in instrumentation, radiochemistry, and data analysis, particularly the introduction of 99M TC-labeled brain-retained tracers for perfusion studies, have opened up a new era of single photon emission computed tomography (SPECT). In this review critical methodological issues relating to the SPECT instrument, the radioactive tracers, the scanning procedure, the data analysis and interpretation of data, and subject selection are discussed together with the changes in regional cerebral blood flow (rCBF) observed in normal aging. An overview is given of the topography and the pathophysiological and diagnostic significance of focal rCBF deficits in Alzheimer's disease and in other dementia disorders, in which SPECT is capable of early or preclinical disease detection. In Alzheimer's disease, the diagnostic sensitivity and specificity of focal rCBF deficits measured with SPECT and brain-retained tracers are very high, in particular when combined with medial temporal lobe atrophy on CT. Together with neuropsychological testing, SPECT serves to map the topography of brain dysfunction. Thus, in the clinical setting, SPECT provides information that is supplemental to that obtained in other studies. Future applications include neuroreceptor studies and treatment studies, in which SPECT may serve as a diagnostic aid in the selection of patients and as a potential mean for monitoring treatment effects. Although positron emission tomography is the best characterized tool for addressing some of these clinical and research issues in dementia, only the less expensive and technically simpler SPECT technique will have the potential of being available as a screening diagnostic instrument in the clinical setting. It is concluded that, properly approached, functional brain imaging with SPECT represents an important tool in the diagnosis, management, and research of dementia disorders.
仪器设备、放射化学及数据分析方面的新进展，尤其是用于灌注研究的99M锝标记脑滞留示踪剂的引入，开启了单光子发射计算机断层扫描（SPECT）的新纪元。在这篇综述中，讨论了与SPECT仪器、放射性示踪剂、扫描程序、数据分析与解读以及受试者选择相关的关键方法学问题，同时也探讨了正常衰老过程中观察到的局部脑血流量（rCBF）变化。概述了阿尔茨海默病及其他痴呆症中局部rCBF缺损的地形图及其病理生理和诊断意义，其中SPECT能够早期或临床前检测疾病。在阿尔茨海默病中，用SPECT和脑滞留示踪剂测量的局部rCBF缺损的诊断敏感性和特异性非常高，尤其是与CT上的内侧颞叶萎缩相结合时。与神经心理学测试一起，SPECT有助于描绘脑功能障碍的地形图。因此，在临床环境中，SPECT提供的信息是对其他研究所得信息的补充。未来的应用包括神经受体研究和治疗研究，其中SPECT可作为选择患者的诊断辅助手段，并作为监测治疗效果的潜在手段。尽管正电子发射断层扫描是解决痴呆症中一些临床和研究问题的最具特征的工具，但只有成本较低且技术上更简单的SPECT技术有可能作为临床环境中的筛查诊断仪器。结论是，正确应用SPECT进行功能性脑成像，是痴呆症疾病诊断、管理和研究的重要工具。
