Document Type: Original Paper
Department of Physics, Faculty of Science, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
Department of Physics, Faculty of Science, Institut Teknologi Sepuluh Nopember, Kampus ITS Sukolilo – Surabaya 60111, East Java, Indonesia;
Department of Physics, Faculty of Science, Institut Teknologi Sepuluh Nopember, Kampus ITS Sukolilo – Surabaya 60111, East Java, Indonesia
Medical Physicist of Radiotherapy Department, Dr. Soetomo General Hospital, Surabaya 60286, East Java, Indonesia
Introduction: This study aimed to evaluate the synthesized bolus for reducing damage to body tissues or protecting the organ at risk (OAR) in radiotherapy application. Several properties of the synthesized bolus, including density, transmission factor, and effective mass attenuation coefficient, were investigated.
Material and Method: The material of synthesized bolus in this study was Propylene Glycol (PG), Silicon Rubber (SR), and Aluminum (Al). The dimension of the synthesized bolus was molded by using an acrylic cast with the size of 11×11 cm² with a varies the thickness of 0.5, 1, and 1.5 cm. Furthermore, the boluses were irradiated by linear accelerator with a photon beam energy of 6 and 10 MV.
Result: The density of synthesized bolus was evaluated by mass per volume equation, and the result showed that the density of bolus is similar to a density of tissue/water, fat, air. For dosimetry characterization, the bolus was exposed to a photon beam energy of 6 and 10 MV using LINAC Varian 2300ix. The closest value of dosimetry characterization to the body tissues was bolus with the composition of PG 24%; SR 8%; Al 1.5% of all energies with transmission factor was at 0.978 and 0.984 at a thickness of 1.5 cm, and the effective mass attenuation coefficient was at 0.0144 and 0.0107 cm²/g.
Conclusion: In general, the %surface dose revealed that the synthesized bolus could increase the % surface dose, could reduce skin-sparing, and protect the organ at risk (OAR). The fact indicates that the synthesized bolus has a potential application in clinical therapy.