Study Of The Measuring Methods Of Medical Isotopes Standard Measurement Device

With the rapid development of human medicine, nuclear medicine has become an indispensable part of the modern medicine field. In the application of nuclear medicine, radionuclides were commonly used as the drugs of medical diagnosis and treatment. However, excessive radiation could cause some irreversible damage to the human body, and radioactive drugs have obvious particularity than other drugs in use. So it is particularly important for medical radioactive nuclide activity measurement work. Because it is not only the key of ensuring that the security of patients and diagnosis and treatment effect, but also the important part of the development of nuclear medicine.Our work was based on ministry of science and technology quality public welfare projects "The study of medical radionuclide standard measurement traceability method", which was undertook by National Institute of Metrology. Two aspects were contained in this paper:first, for verification work of medical radioactive nuclide activity measurement tool medical activity meter, we completed the establishment of the medical nuclide standard measurement device; Second, explore a new traceability method of medical radioactive radionuclides Activity Meter. Structure is divided into five chapters, the first chapter of the article selected topic background significance, research status, research contents, and elaborates the expected research results; Chapter ii to overview of activity measurement method, mainly on the current activity summarized the principle and method of measurement; The third chapter is the establishment of medical isotopes standard device is to introduce each part of the standard device; Measurement system is introduced in the fourth chapter is the standard device, introduces the standard device of micro current measurement system and the remote verification method based on the remote detection technology, studied the medical isotopes activity meter metrology guarantee scheme, and verified the feasibility; The fifth chapter is the detector performance experiment and system accuracy experiment data and results.The principle and method of medical radionuclide standard apparatus for measuring activity were studied, and we established the measurement standard for medical radionuclide activity measurement device.Medical radionuclide standard measuring device took4πγ high-pressure ionization chamber as the device detector, and Townsend balance principle-based compensation method as a micro-current measurement methods, and automatic measurement, result analysis and test records were realized by the automatic measurement controlled software. After the completion of the standard device, we designed some experiments to test the performance of the detector and the accuracy of system respectively. The test experiments of detector included saturation curve experiment, geometric response experiments, linear experiments and efficiency calibration. The results showed that the activity linearity of established medical radionuclide standard measuring device was better than0.05%;when the polarization voltage was-560V, the output of the ionization current was nearly saturated; when the measurement sample was placed in the center position of the ionization chamber, the ionization chamber could output a maximum ionization current. The test experiments of system included the measurement of background, stability, repeatability and basic error. The results showed that, the background current of the medical radionuclide standard measurement device was less than3×0-14A, the stability of the system was0.10%,and the repeatability was0.035%and the basic error was less than0.60%. The test results showed that the performance of the medical radionuclide standard measurement device achieved the desired requirements.Based on the in-depth research about the status quo of the establishment of the medical radionuclide standard measuring device at home and abroad, and after a careful analysis of the traditional medical radionuclides Activity Meter test method, some problem was found, which existing traditional medical radionuclides value transfer and traceability methods could not be avoided. Accordingly, the Activity Meter Verification of radioactive of RM905a+type was realized by the remote detection technology-based medical radionuclides Activity meter value transfer and traceability method. At the same time, we proposed a measurement assurance program of medical radionuclides activity meter, analyzed and given some solutions of the problems which might encounter in the process of implementation of the medical radionuclide activities Meter measurement, and successfully demonstrated the feasibility of medical radionuclide activity meter assurance program.The establishment of the medical radionuclide standard measurement device solved the problem of medical radionuclides Activity Meter submission, improved the accuracy of measurement of the activity and ensured the quality of medical radionuclides activity meter. Remote detection technology-based verification method provided new direction for the study of new value transfer method, and made a positive contribution for the establishment of medical radionuclides Activity Meter measurement assurance programs and the promotion of the quality assurance program.