Performing phantom measurements for patient-specific quality assurance (PSQA) adds a significant amount of time to the adaptive radiotherapy procedure. Log file based PSQA can be used to increase the efficiency of this process. This study compared the dosimetric accuracy of high-frequency linear accelerator (Linac) log files and low-frequency log data stored in the oncology information system (OIS). Thirty patients were included, that were recently treated in the head and neck (HN), brain, and prostate region with volumetric modulated arc therapy (VMAT) and an additional ten patients treated using stereotactic body radiation therapy (SBRT) with 3D-conformal radiotherapy (3D-CRT) technique. Log data containing a single fraction were used to calculate the dose distributions. The dosimetric differences between Linac log files and OIS logs were evaluated with a gamma analysis with 2%/2 mm criterion and dose threshold of 30%. The original treatment plan was used as a reference. Moreover, DVH parameters of D_98%, D_50%, and D_2% of the planning-target volume (PTV) and dose to several organs at risk (OARs) were reported. Significant differences in dose distributions between the two log types and the original dose were observed for PTV D_98% and D_2% (r < 0.001) for HN cases, PTV D_98% (r = 0.005) for brain cases, and PTV D_50% (r = 0.015) for prostate cases. No significant differences were found between the two log types with respect to D_50%. The root mean square (RMS) error of the leaf positions of the OIS log was approximately twice the RMS error of the Linac log file for VMAT plans, but identical for 3D-CRT plans. The relationship between the gamma pass rate and the RMS error showed a moderate correlation for the Linac log files (r = −0.58, p < 0.001) and strong correlation for OIS logs (r = −0.71, p < 0.001). Furthermore, all doses calculated using Linac log files and OIS log data had a GPR >90% for an RMS error < 3.3 mm. Based on these findings, a tolerance limit of RMS error of 3.3 mm for considering OIS log based PSQA was established. Nevertheless, the OIS log data quality should be improved to achieve adequate PSQA.

执行体模测量以实现患者特定的质量保证 (PSQA) 会显着增加适应性放射治疗过程的时间。基于日志文件的 PSQA 可用于提高此过程的效率。本研究比较了高频直线加速器 (Linac) 日志文件和肿瘤信息系统 (OIS) 中存储的低频日志数据的剂量测定精度。纳入的 30 名患者最近在头颈 (HN)、大脑和前列腺区域接受了容积调制弧形治疗 (VMAT) 治疗，另外 10 名患者使用立体定向身体放射治疗 (SBRT) 和 3D 适形放射治疗（3D-CRT）技术。包含单个部分的日志数据用于计算剂量分布。直线加速器日志文件和 OIS 日志之间的剂量差异通过采用 2%/2 mm 标准和 30% 剂量阈值的伽马分析进行评估。原来的治疗方案作为参考。此外，D的DVH参数报告了计划目标体积 (PTV) 的_98%、D _50%和 D _{2%以及对多个危险器官 (OAR) 的剂量。对于 HN 病例的 PTV D 98%}和 D _2% (r < 0.001)、脑部病例的PTV D _98% (r = 0.005) 和 PTV D ，两种对数类型和原始剂量之间的剂量分布存在显着差异 前列腺病例为_50%（r = 0.015）。_{就 D 50%}而言，两种原木类型之间没有发现显着差异。对于 VMAT 计划，OIS 日志的叶位置的均方根 (RMS) 误差大约是 Linac 日志文件的 RMS 误差的两倍，但对于 3D-CRT 计划则相同。伽玛通过率和 RMS 误差之间的关系显示，直线加速器测井文件具有中等相关性（r  = -0.58，p  < 0.001），而 OIS 测井文件则具有很强的相关性（r  = -0.71，p  < 0.001）。此外，使用 Linac 日志文件和 OIS 日志数据计算的所有剂量的 GPR >90%，RMS 误差 < 3.3 mm。基于这些发现，考虑基于 OIS 对数的 PSQA，建立了 3.3 mm 的 RMS 误差容限。尽管如此，OIS 日志数据质量仍应提高，以实现足够的 PSQA。