Department of Physics of Accelerators and Radiation Medicine, Lomonosov Moscow State University School of Physics, Moscow, Russia.
Moscow Gamma Knife Center, JSC "Neurosurgery Business Center", Moscow, Russia.
J Appl Clin Med Phys. 2022 Jul;23(7):e13637. doi: 10.1002/acm2.13637. Epub 2022 May 30.
To assess differences between frame-based and cone beam computed tomography (CBCT)-defined stereotactic space and to identify predictors of the observed findings.
Differences between frame-based and CBCT-defined stereotactic space after image co-registration were reviewed for 529 patients. Treatment planning system reported the information about the shifts in X, Y, and Z coordinates of the center of the stereotactic space (i.e., coordinate X = 100 mm, Y = 100 mm, and Z = 100 mm) defined by the frame, and the maximum shot displacement (MSD) in mm. We collected the potential predictors of the differences. In total, 19 factors were investigated. We used multiple linear regression to evaluate associations with the increased differences.
Rotational and translational shifts greater than 1° and 1 mm, respectively, were observed in 2.6% of patients. At the same time, a decrease in tumor coverage of more than 5% was detected in 8.3% of cases. It was revealed that the higher fiducial errors (both mean and maximum), the greater weight of the patient, and the lower Karnofsky Performance Scale were predictors of increased rotational, translational shifts, and the MSD.
评估基于框架和锥形束计算机断层扫描（CBCT）定义的立体定向空间之间的差异，并确定观察结果的预测因素。
对 529 名患者的图像配准后基于框架和 CBCT 定义的立体定向空间之间的差异进行了回顾性分析。治疗计划系统报告了框架定义的立体定向空间中心（即坐标 X=100mm、Y=100mm 和 Z=100mm）的 X、Y 和 Z 坐标的移位以及最大射野位移（MSD）的信息（以毫米为单位）。我们收集了差异的潜在预测因素。共研究了 19 个因素。我们使用多元线性回归来评估与差异增大的关联。
分别有 2.6%和 1.0%的患者出现大于 1°和 1mm 的旋转和平移偏差。同时，8.3%的病例发现肿瘤覆盖面积减少超过 5%。结果表明，更高的基准误差（平均值和最大值）、更大的患者体重和更低的卡诺夫斯基表现量表是旋转、平移偏差和 MSD 增大的预测因素。
