THE DOSE DISTRIBUTION FROM IRIDIUM-192 SOURCE ON CERVICAL CANCER BRACHYTHERAPY BY MANCHESTER SYSTEM USING MONTE CARLO SIMULATION (EGSNRC)

• Main Author: Kurniati, Fitri
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49469
• Institution: Institut Teknologi Bandung

Cervical cancer is cancer that ranks second as a deadly disease in women. Cervical cancer is caused by infection with the human papillomavirus (HPV). One treatment for cervical cancer is to use radioactive sources that directly target called brachytherapy. This study used a phantom derived from a CT scan image of the DICOM type pelvis and 50 x 50 x 28.8 cm obtained from Santosa Kopo Hospital. The source used Ir-192, which make in the form of an asymmetrical beam with a size of 0.45 x 0.09 x 0.09 cm. Monte Carlo simulation performs to determine the dose distribution of the Ir-192 source on cervical cancer CT images based on the Manchester system. The Monte Carlo simulation divides into two models of distance variations on the applicator. Model A uses TPS data with a distance between sources 0.9 cm, while model B is to do with a range between sources 0.5 cm. The distribution of dose resulting from the monte Carlo simulation was analyzed and compared with TPS results. The results of this simulation showed that the range of 50% dose distribution in model A reaches the end of 3,9 cm. If it compares with the range of 50% dose distribution at the TPS results reaches 4 cm, it produces a deviation value of 2.5%, which is still within the tolerance range. Model A and Model B provide the 50% dose distribution have different. In model B, it reaches 3.86 cm, resulting in a deviation of 1.02%, which is still within the tolerance range. The resulting ?-index value for the 50% dose distribution was 2.26, while the whole area's GPR value was 94.13%; this indicates a difference in dose distribution between the two models. Therefore, the smaller the distance between the sources used, the shorter the dose distribution range with the relatively higher uniform dose distribution.