Distribución de los coeficientes de atenuación lineal en la cavidad abdominopélvica de un fantoma antropomorfo para dosimetría interna con Tc-99m en el Hospital Carlos Andrade Marín.

Abstract

The objective was to determine the distribution of linear attenuation coefficients in the abdominopelvic cavity of an anthropomorphic phantom for internal dosimetry using Tc-99m at the Carlos Andrade Marín Hospital. A computed tomography was performed to the anthropomorphic phantom to delimit the abdominal-pelvic cavity, a point source of Tc-99m was distributed in each point of the axial cut for the acquisition of the data and calculation of the coefficients of linear attenuation of each of the organs, and then determine the absorbed dose in liver and kidney by means of the coefficient method. As a result, an average linear attenuation coefficient of u= 0.158 ± 0.012 cm-1 was obtained, it indicates that the anthropomorphic phantom is radiologically equivalent to the soft tissue. Considering the liver as the source organ, the absorbed dose of the organs of the abdominopelvic cavity is: 1.035 cGy, 0.655 cGy, 0.628 cGy and 0.434 cGy for spleen, liver, kidney and ovary respectively; whereas when considering the kidney as a source organ the bladder, kidney, ovaries and testes receive a dose of 0.29 cGy, 0.092 cGy, 0.018 cGy and 0.01 cGy respectively. It was determined that the values are within the maximum permissible levels for the medical diagnosis in Nuclear Medicine and at the same time it is recommended to continue this investigation with computational tools.