Division of Radiation Oncology, Department of Radiology, King Chulalongkorn Memorial Hospital, Bangkok 10330, Thailand.
Metallurgy and Materials Science Research Institute Chulalongkorn University, Bangkok 10330, Thailand.
J Radiat Res. 2022 May 18;63(3):428-434. doi: 10.1093/jrr/rrac013.
The commercial flat bolus cannot form perfect contact with the irregular surface of the patient's skin, resulting in an air gap. The purpose of this study was to evaluate the feasibility of using a 3D customized bolus from silicone rubber. The silicone rubber boluses were studied in basic characteristics. The 3D customized bolus was fabricated at the nose, cheek and neck regions. The point dose and planar dose differences were evaluated by comparing with virtual bolus. The hardness, thickness, density, Hounsfield unit (HU) and dose attenuation of the customized bolus were quite similar to a commercial bolus. When a 3D customized bolus was placed on the RANDO phantom, it can significantly increase buildup region doses and perfectly fit against the irregular surface shape. The average point dose differences of 3D customized bolus were -1.1%, while the commercial bolus plans showed -1.7%. The average gamma results for planar dose differences comparison of 3D customized bolus were 93.9%, while the commercial bolus plans were reduced to 91.9%. Overall, A silicone rubber bolus produced the feasible dosimetric properties and could save cost compared to a commercial bolus. The 3D printed customized bolus is a good buildup material and could potentially replace and improve treatment efficiency.
商业平板体模不能与患者皮肤的不规则表面形成完美接触，导致存在气隙。本研究旨在评估使用硅橡胶 3D 定制体模的可行性。研究了硅橡胶体模的基本特性。在鼻、颊和颈部区域制作了 3D 定制体模。通过与虚拟体模比较，评估了点剂量和平面剂量差异。定制体模的硬度、厚度、密度、亨氏单位（HU）和剂量衰减与商业体模非常相似。当 3D 定制体模放置在 RANDO 体模上时，它可以显著增加建成区剂量，并与不规则表面形状完美贴合。3D 定制体模的平均点剂量差异为-1.1%，而商业体模计划显示为-1.7%。对于 3D 定制体模平面剂量差异比较的平均伽马结果为 93.9%，而商业体模计划则降低到 91.9%。总的来说，硅橡胶体模具有可行的剂量学特性，与商业体模相比可以节省成本。3D 打印定制体模是一种良好的建成材料，有可能替代并提高治疗效率。
