Yonekura Y, Iwasaki Y, Fujita T, Sasayama S, Matoba N, Sadato N, Tamaki N, Konishi J
Department of Brain Pathophysiology, Kyoto University Faculty of Medicine, Japan.
Kaku Igaku. 1990 Nov;27(11):1311-6.
We have developed a simple method to quantitate brain perfusion SPECT with N-isopropyl-p-[123I]iodoamphetamine (IMP). After an intravenous bolus injection of IMP, serial dynamic images of the brain and the lung were obtained every 5 sec for 2 min, followed by a SPECT scan at 20 min. Based on the assumption of IMP as chemical microspheres, fractional uptake (FU) of IMP in the brain was calculated from the time-activity curves of the total brain and the total lungs. FU showed a strong positive correlation with inverse of the body surface area which was calculated from the height and weight of the individual subject, suggesting that FU is influenced by cardiac output. Quantification of IMP brain perfusion SPECT was attempted with FU and estimated cardiac output in each subject, providing an index of regional cerebral blood flow. Compared with PET measurement of regional cerebral blood flow, the present method tended to overestimate the flow values. This method has a great advantage that it can be applied in many institutions having large field gamma cameras. However, the accuracy of the measurement may be limited in the tall subjects and in the cases with cardiopulmonary diseases, and further investigation is required to clarify the usefulness and limitation of this approach.
我们已经开发出一种用 N-异丙基-p-[123I]碘安非他明（IMP）对脑灌注单光子发射计算机断层扫描（SPECT）进行定量分析的简单方法。静脉推注 IMP 后，每 5 秒获取一次大脑和肺部的连续动态图像，共持续 2 分钟，随后在 20 分钟时进行 SPECT 扫描。基于 IMP 作为化学微球的假设，根据全脑和全肺的时间-活性曲线计算 IMP 在脑中的摄取分数（FU）。FU 与根据个体受试者身高和体重计算出的体表面积倒数呈强正相关，这表明 FU 受心输出量影响。尝试用 FU 和每个受试者估算的心输出量对 IMP 脑灌注 SPECT 进行定量分析，从而提供局部脑血流量指标。与正电子发射断层扫描（PET）测量局部脑血流量相比，本方法往往会高估血流值。该方法具有很大优势，即它可应用于许多配备大视野伽马相机的机构。然而，在高个子受试者以及患有心肺疾病的情况下，测量准确性可能受限，需要进一步研究以阐明该方法的实用性和局限性。
