Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, 68167, Mannheim, Germany.
Fraunhofer Institute for Manufacturing Engineering and Automation, Project Group for Automation in Medicine and Biotechnology, 68167, Mannheim, Germany.
Med Phys. 2019 Dec;46(12):5488-5498. doi: 10.1002/mp.13852. Epub 2019 Oct 23.
Three-dimensional (3D) printing allows for the fabrication of medical devices with complex geometries, such as soft actuators and robots that can be used in image-guided interventions. This study investigates flexible and rigid 3D-printing materials in terms of their impact on multimodal medical imaging.
The generation of artifacts in clinical computer tomography (CT) and magnetic resonance (MR) imaging was evaluated for six flexible and three rigid materials, each with a cubical and a cylindrical geometry, and for one exemplary flexible fluidic actuator. Additionally, CT Hounsfield units (HU) were quantified for various parameter sets iterating peak voltage, x-ray tube current, slice thickness, and convolution kernel.
We found the image artifacts caused by the materials to be negligible in both CT and MR images. The HU values mainly depended on the elemental composition of the materials and applied peak voltage was ranging between 80 and 140 kVp. Flexible, nonsilicone-based materials were ranged between 51 and 114 HU. The voltage dependency was less than 29 HU. Flexible, silicone-based materials were ranged between 60 and 365 HU. The voltage-dependent influence was as large as 172 HU. Rigid materials ranged between -69 and 132 HU. The voltage-dependent influence was <33 HU.
All tested materials may be employed for devices placed in the field of view during CT and MR imaging as no significant artifacts were measured. Moreover, the material selection in CT could be based on the desired visibility of the material depending on the application. Given the wide availability of the tested materials, we expect our results to have a positive impact on the development of devices and robots for image-guided interventions.
三维（3D）打印可制造具有复杂几何形状的医疗设备，例如可用于图像引导介入的软致动器和机器人。本研究调查了柔性和刚性 3D 打印材料对多模态医学成像的影响。
评估了六种柔性和三种刚性材料在临床计算机断层扫描（CT）和磁共振（MR）成像中的伪影生成情况，每种材料都具有立方和圆柱两种几何形状，并且还评估了一个柔性流体致动器的情况。此外，还针对不同的参数集迭代峰值电压、X 射线管电流、切片厚度和卷积核，对各种参数集的 CT 亨氏单位（HU）进行了量化。
我们发现材料在 CT 和 MR 图像中引起的图像伪影可以忽略不计。HU 值主要取决于材料的元素组成，应用的峰值电压范围在 80 到 140 kVp 之间。柔性、非硅基材料的范围在 51 到 114 HU 之间。电压依赖性小于 29 HU。柔性、硅基材料的范围在 60 到 365 HU 之间。电压依赖性影响高达 172 HU。刚性材料的范围在-69 到 132 HU 之间。电压依赖性影响小于 33 HU。
在 CT 和 MR 成像期间，所有测试的材料都可用于视野内的设备，因为未测量到明显的伪影。此外，在 CT 中，可以根据应用所需的材料可见度选择材料。鉴于测试材料的广泛可用性，我们预计我们的结果将对用于图像引导介入的设备和机器人的开发产生积极影响。
