Dosimetría en pacientes marcados con Tc99m que se realizan diagnóstico con spect en patologías de tórax en el Hospital de Especialidades Carlos Andrade Marín IESS-Quito.

Abstract

The purpose of this investigation was to determine the internal dosimetry in patients who were undergone to Single Photon Emision Computer Tomography diagnosis. In order to conduct this procedure, it was necessary to find out the absorved dose by the Source organ and White organs by means of radionuclide in thoracic organs (heart end lungs). The aforementioned data were obtained through an anthropomorphic phantom. A Tc99m radiotracer was used to diagnose thoracic pathologies which was applied to anthropomorphic phantom with similar human-like mass tisue density; for each thoracic study it was reiquired data taking from ten patients. The resulting values from obsorbed dose by source organ and White organs wre compared to established limits by ICRP 60. Once the process was concluded the following results were as follows: White organ (heart) 0.049±0.02mGy, Source organ (lungs) 0.07±0.03mGy, which were under established limits; heart attenuation coefficient 0.052±0.03mGy, right lung attenuation coefficient 0.048±0.02mGy, left lung attenuation coefficient 0.054±0.03mGy. Through MIRD method, the following data were obtained: lungs 0.069±0.04 mGy; heart 0.065±0.03mGy, these results verify that there exists a value difference in the lungs and heart because the phantom is an inert material; threfore, the phantom does not perform any metabolic function which does not allow the radiopharmaceutical being eliminated from the organism as it occurs in patients. It is reccommended to continue withthese studies by means of computing tools use.