CALCULATION OF STOPPING POWER AND RANGE OF PROTON IN BODY TISSUES OF THE HUMAN HEAD USING SRIM PROGRAM

• Main Author: Fatimah Ashshidiqiyyah, Syafira
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/53694
• Institution: Institut Teknologi Bandung

The main purpose of radiation therapy is to optimize the received dose in target and minimize the received dose in healthy tissues around the target. Unfortunately, in some cases, especially for tumors or cancers located on the head, the purpose can be hard to achieve and might cause some side effects after therapy. The development of the study regarding the interaction of heavy charge particle –proton for the example, has given hope for the growth of radiation therapy. Protons have an energy transfer characteristics called a Bragg curve, which is relatively low as they enter and continue to increase drastically before its finally stopping. These properties make it possible to irradiate intensely a strictly localized region within the body. Proton have the potential for a significantly lower normal tissue dose, while keeping similar target coverage and will allow for a substantially lower probability of radiation-induced side effects. The range of protons in the matter and the location of the Bragg peaks will occur can be controlled by the initial energy of protons. Therefore, the initial energy of a proton must be determined carefully so the proton can stop at the exact target location. Stopping power and range data of protons are needed as references for the process of treatment planning in proton radiation therapy. The objects in this study are water and body tissues on the human head, namely the eye lens, compact bone, spongy bone, cranium, cerebrospinal fluid (CSF), gray and white matter, and the brain. The proton energy range in this study is 10-250 MeV. The stopping power are calculated using the SRIM program, the Bragg-Kleeman rule, the Bethe-Bloch equation and the Bethe-Bloch empirical equation. The results of these calculations are compared with reference data from the ICRU Report 46. Meanwhile, the proton range is obtained from the SRIM-2013 simulation and the calculation of Bragg-Kleeman rule. From the results of stopping power, a good agreement is obtained between the SRIM-2013 simulation results and each calculation method with the ICRU Report 46 reference data. The SRIM-2013 simulation results have an average difference stopping power of about 1.4% and a standard deviation of 0.3%. As for the proton term, there is a large discrepancy between the SRIM-2013 data and the Bragg-Kleeman rule. The largest percentage of mean range difference was for compact bone, around 29.64%, while the smallest was CSF around 8.19%.