Determinación de los cambios producidos en la sangre por la radiación ionizante, mediante una simulación en GEANT4

Abstract

The purpose of this research project was to develop a simulation that allows the manipulation and study of the effects produced by the interaction of blood with ionizing radiation, used in the diagnosis and treatment of oncological, neurological, and cardiovascular diseases. For this purpose, an anthropomorphic phantom was developed with the radiosensitive organs (brain, eyes, heart, lung, liver, kidneys, stomach) and the cardiovascular system was specified. Considering the leg as the source organ and the blood clot as the target organ; initial simulation parameters were defined for the radiopharmaceutical Cs-137 and F-18 with activities of 2200 curies and 15 millicuries respectively from which histograms and depth dose profiles were extracted. The simulation was performed in the Geant4 software widely used in various areas applied to medical physics. Using 1 millimeter voxel detector arrays placed on the target organ of the phantom the radiation dose to the blood clot was determined. As a result, the dose absorbed by the blood clot was 3,85E-11 Grays (Gy) for the Cs-137 source and 7,0998E-12 Gy for the F-18 respectively. It is concluded that the value of the dose absorbed by the blood is below the 0,3 Gy established by the International Commission Radiological Protection where the changes produced by ionizing radiation in the blood are recorded. Its application in in vitro tests with irradiated activity is suggested, so that it can be used for the diagnosis and treatment of blood pathologies such as deep venous thrombosis and pulmonary thromboembolism.