Department of Radiology, Seirei Hamamatsu General Hospital, 2-12-12, Sumiyoshi, Naka-Ward, Hamamatsu, Shizuoka, 430-8558, Japan.
School of Medical Sciences, Fujita Health University, 1-98, Dengakugakubo, Kutsukake-Cho, Toyoake, Aichi, 470-1192, Japan.
Radiol Phys Technol. 2023 Sep;16(3):366-372. doi: 10.1007/s12194-023-00726-1. Epub 2023 May 30.
A calibration phantom made of Derlin requires manual translational and rotational adjustments when calibrating a light-section-based optical surface monitoring system (VOXELAN) with a phantom material that insufficiently reflects the red-slit laser of the system. This study aimed to develop a new calibration phantom using different materials and to propose a procedure that minimizes setup errors. The new phantom, primarily made of PET100, which exhibits good reflectivity without scattering or attenuating the red-slit laser at the phantom surface, was shaped in a manner similar to that of previous designs. The detection accuracy and stability were evaluated using six different regions of interest (ROIs) and compared with previous phantom designs. The coordinate coincidence between the machine and VOXELAN was compared for both phantom designs. The detection accuracy and stability of the new phantom in the reference ROI setting were found to be better than those of previous phantoms. In the lateral, longitudinal, and vertical directions, the coordinate coincidences in translational directions for the previous phantom were obtained at 1.07 ± 0.66, 1.46 ± 0.47, and 0.26 ± 0.83 mm, whereas those for the new phantom were obtained at 0.28 ± 0.21, 0.18 ± 0.30, and - 0.30 ± 0.29 mm, respectively. The rotational errors of the two phantoms were identical. The new phantom exhibited improved detection stability because of its good reflectivity. Additionally, the new placement procedure was linked to the six-degrees-of-freedom couch. A combination of the new phantom and its new placement procedure is suitable for coordinate calibration of VOXELAN.
一种由 Derlin 制成的校准体模在对光切式光学表面监测系统（VOXELAN）进行校准时，需要手动进行平移和旋转调整，因为校准体模材料对系统的红色狭缝激光的反射不足。本研究旨在开发一种新的校准体模，使用不同的材料，并提出一种最小化设置误差的程序。新的校准体模主要由 PET100 制成，它在体模表面具有良好的反射率，不会散射或衰减红色狭缝激光，形状与之前的设计相似。使用六个不同的感兴趣区域（ROI）评估了检测精度和稳定性，并与之前的体模设计进行了比较。比较了两种体模设计的机器和 VOXELAN 之间的坐标一致性。在参考 ROI 设置下，新体模的检测精度和稳定性均优于之前的体模。在横向、纵向和垂直方向上，以前的体模在平移方向上的坐标一致性分别为 1.07±0.66、1.46±0.47 和 0.26±0.83mm，而新体模的坐标一致性分别为 0.28±0.21、0.18±0.30 和-0.30±0.29mm。两种体模的旋转误差相同。新体模具有良好的反射率，因此检测稳定性得到了提高。此外，新的放置程序与六自由度床架相关联。新的体模及其新的放置程序的组合适合于 VOXELAN 的坐标校准。
