Sato S, Miyabe Y, Nakata M, Tsuruta Y, Nakamura M, Mizowaki T, Hiraoka M
Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine.
Clinical Radiotherapy Service Division, Kyoto University Hospital.
Med Phys. 2012 Jun;39(6Part18):3826. doi: 10.1118/1.4735614.
To evaluate a dosimetric accuracy of AcurosXB dose calculation algorithm for 4 MV photon beam.
Four MV beam (Clinac-6EX) and AAA and AcurosXB algorithms (pre-release version 11.0.03.) were used in this study. The differences of the calculation with AAA (EAAA) and AcurosXB (EAXB) to the measurement were evaluated in the depth doses to 25 cm depth and dose profiles within the water and slab phantoms (water, lung and bone equivalent). In addition, the clinical cases, including three whole breast plans and three head and neck IMRT plans, were evaluated. First the AAA plans were calculated, then AcurosXB plans were recalculated with dose-to-medium with identical beam setup and monitor units as in the AAA plan.
In the water phantom study, the EAAA and EAXB were up to 2.2% and 1.5% in the depth doses for the open field (field size = 4 - 40cm square), respectively. Under the heterogeneity conditions, the EAAA and EAXB were less than 4.4% and 2.2% in lung region, and less than 12.5% and 6.3% in bone region, respectively. In the re-buildup region after passing through the lung phantom, the AAA overestimated the doses about 10%; however AcurosXB had good agreement with measurement within 3%. Dose profiles with AcurosXB were better agreement with measurement than AAA. In the clinical cases, the dose of the skin surface region with AcurosXB were higher than AAA by at least 10%, and the dose differences over 5% appeared in heterogeneous region. However, DVH shapes of each organ were similar between AAA and AcurosXB within 2%.
In phantom study, AcurosXB had better agreement to measurement than AAA, especially in heterogeneous region and re-buildup region. In the clinical cases, there were large differences between AcurosXB and AAA in the surface region. Evaluation Agreement of non-clinical versions of Acuros XB with　Varian Medical Systems.
评估AcurosXB剂量计算算法对4MV光子束的剂量学准确性。
本研究使用了4MV射线束（Clinac-6EX）以及AAA和AcurosXB算法（预发布版本11.0.03）。在25cm深度的深度剂量以及水模和固体模体（水、肺等效模体和骨等效模体）内的剂量分布中，评估了AAA算法（EAAA）和AcurosXB算法（EAXB）计算结果与测量值之间的差异。此外，还对包括三个全乳计划和三个头颈部调强放疗计划在内的临床病例进行了评估。首先计算AAA计划，然后使用与AAA计划相同的射束设置和监测单位，通过剂量到介质的方式重新计算AcurosXB计划。
在水模体研究中，对于开放野（射野尺寸 = 4 - 40平方厘米），深度剂量方面EAAA和EAXB分别高达2.2%和1.5%。在不均匀性条件下，肺区域的EAAA和EAXB分别小于4.4%和2.2%，骨区域分别小于12.5%和6.3%。在穿过肺模体后的再建成区域，AAA高估剂量约10%；然而AcurosXB与测量值的一致性良好，在3%以内。AcurosXB的剂量分布与测量值的一致性比AAA更好。在临床病例中，AcurosXB的皮肤表面区域剂量比AAA至少高10%，并且在不均匀区域出现超过5%的剂量差异。然而，AAA和AcurosXB之间各器官的剂量体积直方图形状在2%以内相似。
在模体研究中，AcurosXB与测量值的一致性比AAA更好，尤其是在不均匀区域和再建成区域。在临床病例中，AcurosXB和AAA在表面区域存在较大差异。Acuros XB非临床版本与瓦里安医疗系统的评估一致性。
