McCarroll Rachel E, Rubinstein Ashley E, Kingsley Charles V, Yang Jinzhong, Yang Peiying, Court Laurence E
Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas, USA; The Graduate School of Biomedical Sciences, The University of Texas Health Science Center, Houston, Texas.
Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas, USA; The Graduate School of Biomedical Sciences, The University of Texas Health Science Center, Houston, Texas, USA.
J Am Assoc Lab Anim Sci. 2015 Sep;54(5):545-8.
We have designed a method for immobilizing the subjects of small-animal studies using a study group-specific 3D-printed immobilizer that significantly reduces interfraction rotational variation. A cone-beam CT scan acquired from a single specimen in a study group was used to create a 3D-printed immobilizer that can be used for all specimens in the same study group. 3D printing allows for the incorporation of study-specific features into the immobilizer design, including geometries suitable for use in MR and CT scanners, holders for fiducial markers, and anesthesia nose cones of various sizes. Using metrics of rotational setup variations, we compared the current setup in our small-animal irradiation system, a half-pipe bed, with the 3D-printed device. We also assessed translational displacement within the immobilizer. The printed design significantly reduced setup variation, with average reductions in rotational displacement of 76% ± 3% (1.57 to 0.37°) in pitch, 78% ± 3% (1.85 to 0.41°) in yaw, and 87% ± 3% (5.39 to 0.70°) in roll. Translational displacement within the printed immobilizer was less than 1.5 ± 0.3 mm. This method of immobilization allows for repeatable setup when using MR or CT scans for the purpose of radiotherapy, streamlines the workflow, and places little burden on the study subjects.
我们设计了一种使用特定研究组的3D打印固定器来固定小动物研究对象的方法，该方法可显著减少分次间的旋转变化。从研究组中的单个标本获取的锥形束CT扫描用于创建可用于同一研究组中所有标本的3D打印固定器。3D打印允许将特定研究的特征纳入固定器设计，包括适用于MR和CT扫描仪的几何形状、基准标记的固定器以及各种尺寸的麻醉鼻锥。使用旋转设置变化的指标，我们将小动物辐照系统中的当前设置（半管床）与3D打印设备进行了比较。我们还评估了固定器内的平移位移。打印设计显著减少了设置变化，俯仰方向的旋转位移平均减少了76%±3%（从1.57°降至0.37°），偏航方向减少了78%±3%（从1.85°降至0.41°），滚动方向减少了87%±3%（从5.39°降至0.70°）。打印固定器内的平移位移小于1.5±0.3毫米。这种固定方法在使用MR或CT扫描进行放射治疗时允许可重复的设置，简化了工作流程，并且对研究对象的负担很小。
