Patient 3D验证左侧乳腺癌根治术后调强放疗中AXB和AAA算法的剂量学差异

Study of the Dosimetric Differences Between AXB and AAA Algorithms in IMRT for After Left Radical Mastectomy by Patient 3D Verified

目的基于Patient 3D,探究左侧乳腺癌根治术后调强放疗计划中Acuros XB(AXB)算法和各向异性解析算法(Anisotropic Analytical Algorithm,AAA)这2种算法的剂量学差异。方法选取左侧乳腺癌根治术后放疗患者26例,采用Eclipse15.5治疗计划系统(Treatment Planning System,TPS)设计固定野动态调强计划,使用AAA算法和AXB算法计算剂量沉积,导入IBA compass软件系统Patient 3D模块进行2种算法独立计算重建剂量,对比各结构的剂量学参数及验证结果。结果TPS计算结果表明,AXB算法左肺的V_(5)、D_(mean)显著低于AAA算法(P<0.05)。Patient 3D结果表明,2种算法各有优缺点,其中右肺、左肺、心脏、健侧乳腺的Dmean和D1,以及左肺V_(5)AXB算法与TPS优化结果一致性优于AAA算法。2种算法的横断面剂量重建γ分析比较,AAA算法在左肺剂量偏差较大。结论左侧乳腺癌根治术后调强放射治疗计划设计中,AAA算法和AXB算法均符合临床要求,AXB算法明显降低了左肺V5的百分体积,在左肺低剂量区更符合TPS实际优化剂量。

Objective To study the dosimetric differences of Acuros XB(AXB)and(anisotropic analytical algorithm)AAA algorithms in intensity modulated radiation therapy(IMRT)after left radical mastectomy bases on patient 3D.Methods A total of 26 patients with after left radical mastectomy and radiotherapy were selected.Eclipse 15.5 treatment planning system(TPS)was used to design the fixed field dynamic intensity modulation plan,AAA algorithm and AXB algorithm were used to calculate the dose deposition,imported to the Patient 3D module of the IBA compass software system and independently calculated the reconstructed dose using two algorithms.The dosimetric parameters and verification results of each structure were compared.Results The result of TPS calculation showed that the V_(5)and D_(mean)of the left lung of AXB algorithm was significantly lower than those of AAA algorithm(P<0.05).Patient 3D results showed that the two algorithms had their own advantages and disadvantages.Dmean and D1 of right lung,left lung,heart and healthy mammary gland,as well as the V5 of the left lung,the consistency of AXB algorithm and TPS optimization results were better than that of the AAA algorithm.Compared with the cross-sectional dose-reconstructionγanalysis of the two algorithms,AAA algorithm had a large dose deviation in the left lung.Conclusion In the planning of after left radical mastectomy IMRT,both AAA algorithm and AXB algorithm meet the clinical requirements.AXB algorithm significantly reduces the percentage volume of V5 in the left lung,which is more in line with the actual optimized dose of TPS in the low dose area of the left lung.