Graphical user interface for yield and doses estimations for cyclotron technetium production

Technetium-99m (^99mTc) production using medical cyclotrons has been proposed to solve the anticipated shortage of ^99mTc, which traditionally is obtained from the reactor-produced generators. Optimizing reaction conditions to maximize ^99mTc production yield becomes crucial. Additionally, since besides ^99mTc, many other undesirable stable and radioactive isotopes can be produced, reaction parameters must also minimize their production yields. Manual calculations of all these yields are very time consuming. Therefore, the aim of our study was to create a graphical user interface (GUI) that would automate these calculations. The GUI, based on Matlab, includes three layers, allowing for yields calculations, and facilitating gamma spectrum analysis. Moreover, the impact of different technetium impurities on patient doses can be evaluated. Theoretical estimates obtained from the GUI were compared with the results of four cyclotron runs. The gamma spectroscopy measurements were performed at multiple time points using an HPGe detector. The preliminary results showed that the activities of ^99mTc measured at 3h post irradiation agree well with theoretical predictions, indicating that the theoretical cross sections reflect well the true reaction probabilities. Agreement between measured and predicted activities for other isotopes varied. Our initial experience shows that theoretical estimates provided by this GUI helped us to efficiently analyze gamma spectroscopy data from early cyclotron experiments, allowing us to test the method and optimize production parameters. We expect however that the main advantage of this GUI will be at the later clinical stage when entering reaction parameters will allow the users to predict production yields and estimate radiation doses for each particular cyclotron run.