Bolus Alternatif Berbahan Termoplastik pada Radioterapi

Abstract

Background: Unused thermoplastic masks have the potential to be recycled as boluses because the thermoplastic base material is also used as bolus material and has been researched to increase the surface dose. However, before being used as a bolus, it requires processing techniques first. This research aims to determine the design, how it works and test the function of the bolus

Methods: This research is exploratory research. Research was carried out on design, working methods and functional tests in the form of density, homogeneity, surface dose and conformity. The bolus is made and then scanning is carried out on the bolus that has been made. The scanning image obtained is then processed at the TPS to obtain HU, air-gap and surface dose values. The data that has been obtained is analyzed to determine the characteristics of each bolus that has been made. Based on the results of the analysis, it can be seen whether the bolus that has been made meets the criteria for good bolus material.

Results: Thermoplastic bolus is hard, does not crack easily, and does not change shape easily. To produce this bolus, it is done through a process of cutting the mask into smaller pieces, pulverizing to remove holes and produce a dense material, and printing. The bolus can be shaped and positioned as long as it is still warm 2 minutes after printing. Thermoplastic bolus has the potential as an alternative bolus with characteristics of a density value of 30 HU, homogeneity with a standard deviation of ±11, conformity with the highest air-gap of 0.3 cm, and a dose to the phantom surface of 99.1%.

Conclusions: Based on the assessment of the characteristics of the thermoplastic bolus, it has the potential to be used as an alternative bolus. In further research, it is hoped that more efficient manufacturing techniques can be developed with better results and tests that have not yet been carried out.