UNASSIGNED:这项研究使用基于3D锥形束计算机断层扫描(CBCT)和立体千伏成像(ExacTrac)的6D定位,评估了脊柱立体定向身体放射治疗(SBRT)期间患者的平移和旋转内部运动。目的是确定额外的分数内图像验证是否减少了分数内运动,而不会显着延长治疗时间。同时保持可接受的成像相关剂量。
UNASSIGNED:对2018年9月至2021年5月期间接受SBRT治疗的38例41例原发肿瘤体积患者进行回顾性分析。评估了三种不同的图像引导放射治疗(IGRT)工作流程。不同成像工作流程的平移和旋转定位误差,评估了针对不同成像工作流程递送的3D平移向量和成像剂量的估计。
UNASSIGNED:随着分数内成像的频率从工作流程1增加到3,平均分数内3D平移矢量从0.91mm(±0.52mm)提高,至0.64(±0.34mm)。85%,对于工作流程1、2和3,83%和97%的图像分别在1mm/1°的公差内,基于后处理CBCT图像。工作流程3的平均治疗时间为13分钟,与工作流1和2的12分钟相比。IGRT工作流程1、2和3的每次治疗的有效剂量测量为0.6mSv,分别为0.95mSv和1.8mSv。
UNASSIGNED:研究表明,在脊柱SBRT期间使用额外的分数内立体千伏图像引导,减少了被认为“超出公差”的测量次数,并且可以在标准治疗时隙内优化治疗交付,而无需施加大量额外的辐射剂量。
UNASSIGNED: This study evaluated translational and rotational intra-fractional patient movement during spinal stereotactic body radiotherapy (SBRT) using 6D positioning based on 3D cone beam computerized tomography (CBCT) and stereoscopic kilovoltage imaging (ExacTrac). The aim was to determine whether additional intra-fractional image verification reduced intra-fractional motion without significantly prolonging treatment time, whilst maintaining acceptable imaging related dose.
UNASSIGNED: A retrospective analysis of 38 patients with 41 primary tumour volumes treated with SBRT between September 2018 and May 2021 was performed. Three different image-guided radiotherapy (IGRT) workflows were assessed. The translational and rotational positioning errors for the different imaging workflows, 3D translational vectors and estimates of imaging dose delivered for the different imaging workflows were evaluated.
UNASSIGNED: As the frequency of intra-fractional imaging increased from workflow 1 to 3, the mean intra-fraction 3D translational vector improved from 0.91 mm (±0.52 mm), to 0.64 (±0.34 mm). 85 %, 83 % and 97 % of images were within a tolerance of 1 mm/1° for workflows 1, 2 and 3 respectively, based on post treatment CBCT images. The average treatment time for workflow 3 was 13 min, as compared to 12 min for workflows 1 and 2. The effective dose per treatment for IGRT workflows 1, 2 and 3 measured 0.6 mSv, 0.95 mSv and 1.8 mSv respectively.
UNASSIGNED: The study demonstrated that the use of additional intra-fractional stereoscopic kilovoltage image-guidance during spinal SBRT, reduced the number of measurements deemed \"out of tolerance\" and treatment delivery could be optimized within a standard treatment timeslot without applying substantial additional radiation dose.