PDF(Pubmed)
Abstract：
Accurately calculating setup errors is crucial in ensuring quality assurance for patients undergoing radiation therapy treatment. This cross-sectional study aimed to determine the systematic, random, and planning target volume (PTV) margin errors for patients with head and neck cancer (n=48) and breast cancer (n=50). The treatment setup was performed using electronic portal imaging (EPIDs) and irradiated using Elekta linac. The errors were calculated using the van Herk formula. The systematic error for the head and neck was 0.89, 0.43, and 1.49 mm on the x, y, and z-axis, respectively, and 0.39, 0.74, 0.38 for the breast cases. The random error was 0.82, 0.68, 0.94 mm for the head and neck and 0.66, 0.72, 0.79 mm for the breast. The PTV margin shifting error for the head and neck were 2.79, 1.55, and 4.38 mm, while it was 1.43, 2.35, and 1.50 mm for the breast. The setup errors varied according to the tumor location. The study highlights the potential benefits of using EPIDs for reducing uncertainties in setup verification procedures.
摘要：
准确计算设置误差对于确保接受放射治疗的患者的质量保证至关重要。这项横断面研究旨在确定系统的，随机,头颈部肿瘤（n=48）和乳腺癌（n=50）患者的计划目标体积（PTV）切缘误差。使用电子射野成像（EPID）进行治疗设置，并使用Elektalinac进行照射。误差是使用vanHerk公式计算出来的。在x上，头颈部的系统误差分别为0.89、0.43和1.49mm，y,和z轴，分别,乳腺病例为0.39、0.74、0.38。头部和颈部的随机误差为0.82、0.68、0.94mm，乳房的随机误差为0.66、0.72、0.79mm。头颈部的PTV裕度偏移误差分别为2.79、1.55和4.38mm,而乳房为1.43、2.35和1.50mm。设置误差根据肿瘤位置而变化。该研究强调了使用EPID减少设置验证程序不确定性的潜在好处。
