Austrian Center for Medical Innovation and Technology (ACMIT), Wiener Neustadt, Austria; Research center for Medical Image Analysis and Artificial Intelligence (MIAAI), Department of Medicine, Faculty of Medicine and Dentistry, Danube Private University, Krems, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
Z Med Phys. 2023 May;33(2):168-181. doi: 10.1016/j.zemedi.2022.05.002. Epub 2022 Jul 2.
To develop and validate a simple approach for building cost-effective imaging phantoms for Cone Beam Computed Tomography (CBCT) using a modified Polyjet additive manufacturing technology where a single material can mimic a range of human soft-tissue radiation attenuation.
Single material test phantoms using a cubic lattice were designed in 3-Matic 15.0 software . Keeping the individual cubic lattice volume constant, eight different percentage ratio (R) of air: material from 0% to 70% with a 10% increment were assigned to each sample. The phantoms were printed in three materials, namely Vero PureWhite, VeroClear and TangoPlus using Polyjet technology. The CT value analysis, non-contact profile measurement and microCT-based volumetric analysis was performed for all the samples.
The printed test phantoms produced a grey value spectrum equivalent to the radiation attenuation of human soft tissues in the range of -757 to +286 HU on CT. The results from dimensional comparison analysis of the printed phantoms with the digital test phantoms using non-contact profile measurement showed a mean accuracy of 99.07 % and that of micro-CT volumetric analysis showed mean volumetric accuracy of 84.80-94.91%. The material and printing costs of developing 24 test phantoms was 83.00 Euro.
The study shows that additive manufacturing-guided macrostructure manipulation modifies successfully the radiographic visibility of a material in CBCT imaging with 1 mm resolution, helping customization of imaging phantoms.
开发并验证一种使用经过改进的 Polyjet 增材制造技术来构建经济高效的锥形束 CT（CBCT）成像体模的简单方法，该技术可以使用单一材料模拟一系列人体软组织的辐射衰减。
在 3-Matic 15.0 软件中设计了使用立方晶格的单一材料测试体模。保持单个立方晶格体积不变，为每个样本分配了从 0%到 70%的空气：材料的八个不同百分比比（R），增量为 10%。使用 Polyjet 技术，将这些体模打印在三种材料中，即 VeroPureWhite、VeroClear 和 TangoPlus。对所有样本进行 CT 值分析、非接触式轮廓测量和基于 microCT 的体积分析。
打印的测试体模在 CT 上产生了从-757 到+286 HU 的人体软组织辐射衰减等效的灰度值谱。使用非接触式轮廓测量对打印体模与数字测试体模的尺寸比较分析结果表明，平均精度为 99.07%，微 CT 体积分析的平均体积精度为 84.80-94.91%。开发 24 个测试体模的材料和打印成本为 83.00 欧元。
该研究表明，增材制造引导的宏观结构操作成功地改变了 CBCT 成像中材料的射线照相可见度，分辨率为 1 毫米，有助于定制成像体模。
