Pieri P, Fischman A J, Ahmad M, Moore R H, Callahan R J, Strauss H W
Department of Radiology, Massachusetts General Hospital, Boston 02114.
J Nucl Med. 1991 May;32(5):851-5.
Preclinical evaluation of cardiac drugs may require evaluation of cardiac function in intact animals. To optimize the quality of radionuclide measurements of ventricular function in small animals, a comparison was made of gated blood-pool scans recorded with five blood-pool radiopharmaceuticals (99mTc-labeled human polyclonal IgG, 99mTc-human serum albumin labeled by two methods, and red blood cells radiolabeled with 99mTc via in vivo and in vitro methods) in rats and three pinhole apertures in hamsters. The quality of the radiopharmaceuticals was evaluated by comparing count density ratios (LV/BACKGROUND and LV/LIVER) and ejection fractions recorded with each agent. The edge definition of the left ventricle and count rate performance of the 1-, 2-, and 3-mm apertures was evaluated in hamsters. In general, the images obtained with the radiolabeled cells were superior to those obtained with the labeled proteins and no significant differences between the protein preparations were detected. Left ventricular ejection fractions calculated with all five radiopharmaceuticals were not significantly different. The best quality images were obtained with the 1-mm pinhole collimator. Ejection fraction and acquisition time were inversely related to aperture size. A good compromise between resolution and sensitivity was obtained with the 2-mm pinhole collimator.
心脏药物的临床前评估可能需要在完整动物身上评估心脏功能。为了优化小动物心室功能放射性核素测量的质量，比较了用五种血池放射性药物（99mTc标记的人多克隆IgG、两种方法标记的99mTc人血清白蛋白以及通过体内和体外方法用99mTc标记的红细胞）在大鼠身上记录的门控血池扫描以及在仓鼠身上使用的三个针孔孔径。通过比较每种药物记录的计数密度比（左心室/背景和左心室/肝脏）和射血分数来评估放射性药物的质量。在仓鼠身上评估了左心室的边缘清晰度以及1毫米、2毫米和3毫米孔径的计数率性能。一般来说，用放射性标记细胞获得的图像优于用标记蛋白质获得的图像，并且未检测到蛋白质制剂之间的显著差异。用所有五种放射性药物计算的左心室射血分数没有显著差异。用1毫米针孔准直器获得的图像质量最佳。射血分数和采集时间与孔径大小成反比。用2毫米针孔准直器在分辨率和灵敏度之间取得了良好的折衷。
