Goodwin D A, Lang E V, Atwood J E, Dalman R L, Ransone C M, Diamanti C I, McTigue M
Department of Nuclear Medicine, Veterans Administration Medical Center, Palo Alto California 94304.
Nucl Med Commun. 1993 Nov;14(11):1023-9. doi: 10.1097/00006231-199311000-00014.
The viability and biodistribution of 68Ga-mercaptopyridine-N-oxide (MPO)-labelled autologous platelets was studied in 10 patients. The average platelet labelling yield was 36 +/- 12% and injected activity was 2.0 +/- 0.9 mCi 68Ga. The % activity in platelets per ml whole blood was 64 +/- 20% at 15 min-1.0 h postinjection and 76 +/- 14% at 2-4h. The average recovery of platelets (% injected platelets circulating in peripheral blood) was 31 +/- 21% at 15 min-1 h and 39 +/- 20% at 2-4 h. The positron emission tomographic (PET) images showed high circulating vascular background. Two patients had technically inadequate scans, and six were false negative due to high blood background. One patient with a massive pulmonary embolus occurring 24 h prior to scanning had marked uptake of 68Ga platelets in a large clot in the superior branch of the right main pulmonary artery. A second patient, with 68Ga platelets circulating during angioplasty of a left posterior tibial artery stenosis, had intense uptake in the lesion shown on the PET scan obtained 4 h following the procedure. These results indicate good viability of 68Ga-MPO-labelled autologous human platelets, but poor visualization of clots by PET imaging, due to the high blood background at early times.
对10例患者研究了68Ga-巯基吡啶-N-氧化物（MPO）标记的自体血小板的活力和生物分布。血小板平均标记率为36±12%，注射活度为2.0±0.9 mCi 68Ga。注射后15分钟至1小时，每毫升全血中血小板的活度百分比为64±20%，2至4小时时为76±14%。血小板的平均回收率（在外周血中循环的注射血小板百分比）在15分钟至1小时为31±21%，2至4小时为39±20%。正电子发射断层扫描（PET）图像显示循环血管本底较高。2例患者扫描技术上不充分，6例因血液本底高而呈假阴性。1例在扫描前24小时发生大面积肺栓塞的患者，在右主肺动脉上支的一个大血栓中有明显的68Ga血小板摄取。第2例患者在左胫后动脉狭窄血管成形术期间有68Ga血小板循环，术后4小时获得的PET扫描显示病变处有强烈摄取。这些结果表明68Ga-MPO标记的自体人血小板活力良好，但由于早期血液本底高，PET成像对血栓的显影较差。
