| This research investigated a novel design and manufacturing approach for customized radiation modulation devices. Traditional fabrication methods for an electron bolus (a radiation modulation device) have lower precision (mm resolution). The current fabrication method is costly due to the use of expensive equipment and the requirement for dedicated machinist. In addition, its ecological impact is high due to higher material usage. In this research, the fused deposition modeling (FDM) technique was used to develop a hollow bottle-like electron bolus design with higher precision (?m resolution). The new design requires less amount of material, cost, and build time as compared to the traditional design and manufacturing method. A design of experiments approach was implemented to observe the effect of different input factors on the radiation modulation properties. These factors include bolus material, manufacturing orientation, loading force, and bolus wall thickness. The two materials used in this study were polycarbonate (PC), and acrylonitrile butadiene styrene (ABS). Bolus wall thickness of 1mm and 3mm was used to evaluate differences in radiation profiles. The boluses were subjected to high radiation doses and mechanical loads to check for dimensional deformations and impact on subsequent radiation profiles. The dimensional deviation analysis performed by comparing the cloud points of the bolus geometry pre and post radiation exposure indicated no significant differences. The flexural mechanical loading test demonstrated that the ABS material had lower deformation as compared to the PC. Finite element analysis of the bolus showed consistent results with mechanical loading tests. This research lays the foundation for the design and manufacture of next generation radiation modulation devices to be used in cancer therapy. |
