Recently, VOLO™ was introduced as a new optimizer for CyberKnife® planning. In this study, we investigated possibilities to improve treatment plans for MLC‐based prostate SBRT with enhanced peripheral zone dose while sparing the urethra, and central lung tumors, compared to existing Sequential Optimization (SO). The primary focus was on reducing OAR doses. For 25 prostate and 25 lung patients treated with SO plans, replanning with VOLO™ was performed with the same planning constraints. For equal PTV coverage, almost all OAR plan parameters were improved with VOLO™. For prostate patients, mean rectum and bladder doses were reduced by 34.2% (P < 0.001) and 23.5% (P < 0.001), with reductions in D_0.03cc of 3.9%, 11.0% and 3.1% for rectum, mucosa and bladder (all P ≤ 0.01). Urethra D_5% and D_10% were 3.8% and 3.0% lower (P ≤ 0.002). For lung patients, esophagus, main bronchus, trachea, and spinal cord D_0.03cc was reduced by 18.9%, 11.1%, 16.1%, and 13.2%, respectively (all P ≤ 0.01). Apart from the dosimetric advantages of VOLO™ planning, average reductions in MU, numbers of beams and nodes for prostate/lung were 48.7/32.8%, 26.5/7.9% and 13.4/7.9%, respectively (P ≤ 0.003). VOLO™ also resulted in reduced delivery times with mean/max reductions of: 27/43% (prostate) and 15/41% (lung), P < 0.001. Planning times reduced from 6 h to 1.1 h and from 3 h to 1.7 h for prostate and lung, respectively. The new VOLO™ planning was highly superior to SO planning in terms of dosimetric plan quality, and planning and delivery times.

中文翻译：

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使用新型优化程序获得的OAR剂量大大减少，并针对具有挑战性的SBRT机械手案例计划和交付时间

近日，VOLO™引入作为射波刀一个新的优化®计划。在这项研究中，与现有的顺序优化（SO）相比，我们研究了改善基于MLC的前列腺SBRT的治疗方案的可能性，该方案具有增加的外周区剂量，同时保留尿道和中央肺部肿瘤。主要重点是减少OAR剂量。对于接受SO计划治疗的25例前列腺和25例肺部患者，在相同的计划约束下使用VOLO™进行了重新计划。为了获得相等的PTV覆盖率，VOLO™改善了几乎所有OAR计划参数。对于前列腺患者，平均直肠和膀胱剂量减少了34.2％（P  <0.001）和23.5％（P  <0.001），D减少了_0.03cc的3.9％，11.0％和直肠，粘膜和膀胱（所有3.1％P  ≤0.01）。尿道d _5％和d _10％分别为3.8％和3.0％下（P  ≤0.002）。对于肺的病人，食道，主支气管，气管，和脊髓d_{且小于等于0.03cc}由18.9％，11.1％，16.1％，和13.2％，分别为（所有降低P  ≤0.01）。除了VOLO™计划的剂量学的优势，在MU平均削减，梁柱节点前列腺/肺癌的人数分别为48.7 / 32.8％，分别26.5 / 7.9％和13.4 / 7.9％（P  ≤0.003）。VOLO™还缩短了交付时间，平均/最大降低了：27/43％（前列腺）和15/41％（肺），P<0.001。前列腺和肺的计划时间分别从6 h减少到1.1 h，从3 h减少到1.7 h。就剂量计划质量，计划和交付时间而言，新的VOLO™计划比SO计划要高得多。