Higano S, Shishido F, Aizawa Y, Miura S, Murakami M, Inugami A, Kanno I, Fujita H, Uemura K
Department of Radiology and Nuclear Medicine, Research Institute for Brain and Blood Vessels, Akita.
Kaku Igaku. 1990 Jan;27(1):51-4.
To clarify the kinetics of N-isopropyl [123I]p-iodoamphetamine (IMP) in the brain, 2-compartment analysis was applied for brain SPECT with 57-minute dynamic scan in 9 subjects. The model consisted of blood component and brain tissue component. Two transfer rate constants were defined; k1 showed the rate from the blood to the brain tissue, and k2 was that of back diffusion. The late scan was performed 210 minutes after the tracer injection. Suitable k values best fitting to the dynamic data were determined for all regions of interest. Predicted regional cerebral activity at 210 minutes using 57-minute dynamic data was well agreed with measured activity. These showed the kinetics of IMP in the brain was well described by the 2-compartment model. The partition coefficient (k1/k2 ratio) was as large as about 35, and almost constant in the various brain structures including hypoperfused areas. These findings indicated that the initial IMP images reflected the reasonable CBF distribution, which gave relatively reliable CBF values even if using microsphere model.
为阐明 N-异丙基[123I]对碘安非他明（IMP）在脑内的动力学，对 9 名受试者进行了 57 分钟动态扫描的脑 SPECT 检查，并应用二室分析。该模型由血液成分和脑组织成分组成。定义了两个转运速率常数；k1 表示从血液到脑组织的速率，k2 是反向扩散的速率。在示踪剂注射后 210 分钟进行延迟扫描。为所有感兴趣区域确定了最适合动态数据的合适 k 值。使用 57 分钟动态数据预测的 210 分钟时的区域脑活性与测量活性高度一致。这些结果表明，IMP 在脑内的动力学可用二室模型很好地描述。分配系数（k1/k2 比值）高达约 35，在包括灌注不足区域在内的各种脑结构中几乎恒定。这些发现表明，初始 IMP 图像反映了合理的脑血流量分布，即使使用微球模型也能给出相对可靠的脑血流量值。
