Booij J, Hemelaar T G, Speelman J D, de Bruin K, Janssen A G, van Royen E A
Graduate School of Neurosciences, Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, The Netherlands.
J Nucl Med. 1999 May;40(5):753-61.
Parkinson's disease is characterized by degeneration of dopaminergic neurons, resulting in loss of dopamine transporters in the striatum. Recently, the tracer 1231-N-omega-fluoropropyl-2beta-carbomethoxy-3beta-(4-iodoph enyl)nortropane (FPCIT) was developed for imaging dopamine transporters with SPECT. The purpose of this study was to develop an [123I]FPCIT SPECT protocol for routine clinical studies.
We examined the time course of [123I]FPCIT binding to dopamine transporters in 10 healthy volunteers and 19 patients with Parkinson's disease.
We found that the time of peak specific striatal [123I]FPCIT binding was highly varied among subjects, but specific binding peaked in all controls and patients within 3 h postinjection. Between 3 and 6 h, the ratio of specific-to-nonspecific striatal [123I]FPCIT binding was stable in both groups, although, as expected, it was significantly lower in patients. In the patients, [123I]FPCIT binding in the putamen was lower than in the caudate nucleus, and contralateral striatal binding was significantly lower than ipsilateral striatal binding. The subgroup of patients with hemi-Parkinson's disease showed loss of striatal dopamine transporters, even on the ipsilateral side.
For routine clinical [123I]FPCIT SPECT studies, we recommend imaging at a single time point, between 3 and 6 h postinjection, and using a tissue ratio as the outcome measure. The [123I]FPCIT SPECT technique is sensitive enough to distinguish control subjects from patients with Parkinson's disease, even at an early stage of the disease.
帕金森病的特征是多巴胺能神经元变性，导致纹状体中多巴胺转运体丧失。最近，示踪剂123I-N-ω-氟丙基-2β-甲氧基羰基-3β-(4-碘苯基)降冰片烷（FPCIT）被开发用于单光子发射计算机断层显像（SPECT）成像多巴胺转运体。本研究的目的是为常规临床研究开发一种[123I]FPCIT SPECT方案。
我们检测了10名健康志愿者和19名帕金森病患者中[123I]FPCIT与多巴胺转运体结合的时间进程。
我们发现，纹状体[123I]FPCIT特异性结合峰值时间在受试者之间差异很大，但所有对照组和患者在注射后3小时内特异性结合均达到峰值。在注射后3至6小时之间，两组纹状体[123I]FPCIT特异性与非特异性结合的比率均保持稳定，不过正如预期的那样，患者组的该比率明显更低。在患者中，壳核中的[123I]FPCIT结合低于尾状核，对侧纹状体结合明显低于同侧纹状体结合。偏侧帕金森病患者亚组即使在同侧也显示出纹状体多巴胺转运体丧失。
对于常规临床[123I]FPCIT SPECT研究，我们建议在注射后3至6小时之间的单个时间点进行成像，并使用组织比率作为结果指标。[123I]FPCIT SPECT技术足够灵敏，即使在帕金森病早期也能将对照受试者与患者区分开来。
