Multi-energy autoradiography with solid state detector.

目前，各种类型的新型放射性核素制剂不断开发，能够揭示器官的病理生理信息。例如在心肌组织分析中，我们可以评估各种心肌功能；局部心肌灌注使用Tl-201或Tc-99m TF，脂肪代谢使用I-123 BMIPP，交感神经功能使用I-123 MIBG，心肌梗死使用Tc-99m PYP。为了了解缺血、心肌病、心力衰竭等各种心肌疾病的病理生理状况，必须对上述局部心肌功能进行评估。然而，每种试剂的成像必须单独进行，因为目前可用的探测器，如x射线胶片或成像板不能分离能谱。高纯度固态锗（HPGe）探测器能以高灵敏度清晰地探测x射线和伽马射线能谱。本实验研制了多能放射自成像系统。该系统由（HPGe）探测器、准直器、扫描工作台和计算机系统组成。在幻影实验中，Tc-99m、I-123和Tl-201可以清晰成像。在I-125 BMIPP和Tl-201灌注的正常心肌中，两种药物可明显分离。该初步系统的空间分辨率与成像板相比较差，但不同的放射性核素制剂可以同时清晰地分离。多能量放射自显像与固体探测器同时分析病理生理状况的可能性很大。

Now various types of new radionuclide agents, which can reveal the patho-physiological informations of organ, has been developing. For example in the analysis of myocardial tissue, we can assess the various myocardial function ; regional myocardial perfusion using Tl-201 or Tc-99m TF,fatty metabolism using I-123 BMIPP,sympathetic nerve function using I-123 MIBG,and myocardial infarction using Tc-99m PYP.To understand the patho-physiological conditions in various myocardial diseases as ischemia, cardiomyopathy and heart failure, regional myocardial function mentioned above must be assessed. However, imaging of each agents must be performed separately because the present available detector such as x-ray film or imaging plate cannot separate energy spectrum.Highly purified germanium solid state (HPGe) detector can detect the energy spectrum of x-ray and gamma ray clearly with highly sensitivity. Multi-energy autoradiographic system was develope in this experiment. This system consisted of (HPGe) detector, collimator, scan table and computer system. Inthe phantom experiment, Tc-99m, I-123 and Tl-201 could clearly imaged. In the normal myocardium perfused by I-125 BMIPP and Tl-201, each agents could be separated clearly. The spatial resolution of this preliminary system was poor comparing to the imaging plate, but the different radionuclide agent colud be clearly separated simultaneously.Multi-energy autoradiography with solid state detector was thought to have great possibility to analyze patho-physiological condition at same time.