COMPARISON OF IMP & HMPAO CEREBRAL SPECT IN ALZHEIMERS

本研究将比较两个单光子发射计算的效用 断层扫描（SPECT）放射性药物-N-异丙基-p-123 l- 碘苯丙胺（IMP）和99 mTc-六甲基丙烯胺肟（HMPAO）- in 检测轻度阿尔茨海默病（AD）的脑灌注缺陷。 由此获得的知识将对本领域的工作作出重大贡献。 领域 虽然许多研究人员发现灌注不足， AD使用单个药物制剂，几乎没有工作已经投入 涉及为此目的选择上级试剂。 作为诊断 SPECT在AD中的有用性最终取决于其检测 在病程早期的细微病变，比较示踪剂研究 不仅是及时的，而且是必要的。 本研究的受试者将包括20名轻度AD患者和10名健康受试者。 匹配的控制。 经过仔细的诊断评估， 神经心理学测试，每名受试者将接受两次脑SPECT 扫描-使用IMP和HMPAO -在30天内以平衡 秩序 将使用最近设计的SPECT系统进行扫描， 具有多层面全脑成像功能 横断层图像 大脑皮层和小脑的感兴趣区域 (ROI)将被定义。 示踪剂分布的区域指数将 通过将皮质ROI的每像素平均计数率除以 小脑的ROI 方差分析和判别分析 将执行，以确定 放射性药物和ROI最大限度地区分阿尔茨海默病患者 从正常人。

This study will compare the utility of two single photon emission computed tomography (SPECT) radiopharmaceuticals - N-isopropyl-p-123l- iodoamphetamine (IMP) and 99mTc-hexamethylpropyleneamine oxime (HMPAO) - in detecting cerebral perfusion deficits in mild Alzheimer's Disease (AD). The knowledge thus derived will represent a substantial contribution to the field. For while numerous investigators have found perfusion deficits in AD using individual pharmaceutical agents, almost no work has been devoted to the selection of a superior agent for this purpose. As the diagnostic usefulness of SPECT in AD will ultimately depend on its ability to detect subtle lesions early in the course of illness, a comparative tracer study is not only timely, but essential. Subjects for the study will include 20 patients with mild AD and 10 healthy matched controls. Following a careful diagnostic evaluation and neuropsychological testing, each subject will undergo two cerebral SPECT scans - with IMP and HMPAO - within a 30 day period in a counter-balanced order. Scans will be performed with a recently designed SPECT system which has multi-slice whole brain imaging capabilities. Transverse slice images will be reconstructed, and cortical and cerebellar regions of interest (ROI) will then be defined. Regional indices of tracer distribution will be computed by dividing mean count rate per pixel for cortical ROIs by that of cerebellar ROIs. An analysis of variance and a discriminant analysis will be performed in order to determine which combination of radiopharmaceutical and ROI maximally discriminates Alzheimer's patients from normals.