Chatal J F
Service de Médecine Nucléaire, Centre René Gauducheau, Nantes.
Ann Endocrinol (Paris). 1990;51(3-4):144-7.
The purpose of scintigraphic imaging is not to explore the morphology of an organ (or its abnormalities) but rather its functional and metabolic characteristics. It is thus important that a molecular structure (e.g., a hormonal receptor or an antigen) closely linked to the functional activity of an organ or tissue be targeted on its cell surface. Such diagnostic targeting requires the synthesis and labeling of a radiopharmaceutical substance specific for the receptor or antigen in question. It also requires a detection system adapted to count rates and signal-to-background ratios (generally moderate). The synthesis of new radiopharmaceutical agents, a critical stage for the future of nuclear medicine, is a long and often risky process in which success is difficult to foresee. Radiolabeling must be stable in vitro and in vivo, and the radiopharmaceutical must subsequently retain its capability of recognizing the targeted molecule. In endocrinology, the exemplary achievement in this direction has been the synthesis of 131I-6-iodomethylnorcholesterol and 131I-metaiodobenzylquanidine for functional scintigraphy of the adrenal cortex and medulla. Progress in detection equipment has been marked by the development of monophotonic tomoscintigraphy, using gamma cameras with a revolving head to obtain slices in different spatial planes showing the distribution in the organism of the injected radiopharmaceutical agent.
闪烁成像的目的不是探究器官的形态（或其异常情况），而是其功能和代谢特征。因此，与器官或组织功能活动密切相关的分子结构（如激素受体或抗原）在其细胞表面被靶向定位非常重要。这种诊断靶向需要合成并标记针对相关受体或抗原的放射性药物。它还需要一个适应计数率和信噪比（通常适中）的检测系统。新放射性药物制剂的合成是核医学未来的关键阶段，这是一个漫长且往往有风险的过程，成功难以预见。放射性标记在体外和体内都必须稳定，并且放射性药物随后必须保持其识别靶向分子的能力。在内分泌学领域，这方面的典型成就是合成了用于肾上腺皮质和髓质功能闪烁成像的131I - 6 - 碘甲基去甲胆固醇和131I - 间碘苄胍。检测设备的进展以单光子断层闪烁成像的发展为标志，它使用带有旋转头的伽马相机获取不同空间平面的切片，显示注入的放射性药物在生物体中的分布。
