Department of Radiation Oncology, University of Wuerzburg, Wuerzburg, Germany.
Radiat Oncol. 2021 Nov 6;16(1):213. doi: 10.1186/s13014-021-01942-y.
To implement a tangential treatment technique for whole breast irradiation using the Varian Halcyon and to compare it with Elekta Synergy Agility plans.
For 20 patients two comparable treatment plans with respect to dose coverage and normal tissue sparing were generated. Tangential field-in-field treatment plans (Pinnacle/Synergy) were replanned using the sliding window technique (Eclipse/Halcyon). Plan specific QA was performed using the portal Dosimetry and the ArcCHECK phantom. Imaging and treatment dose were evaluated for treatment delivery on both systems using a modified CIRS Phantom.
The mean number of monitor units for a fraction dose of 2.67 Gy was 515 MUs and 260 MUs for Halcyon and Synergy Agility plans, respectively. The homogeneity index and dose coverage were similar for both treatment units. The plan specific QA showed good agreement between measured and calculated plans. All Halcyon plans passed portal dosimetry QA (3%/2 mm) with 100% points passing and ArcCheck QA (3%/2 mm) with 99.5%. Measurement of the cumulated treatment and imaging dose with the CIRS phantom resulted in lower dose to the contralateral breast for the Halcyon plans.
For the Varian Halcyon a plan quality similar to the Elekta Synergy device was achieved. For the Halcyon plans the dose contribution from the treatment fields to the contralateral breast was even lower due to less interleaf transmission of the Halcyon MLC and a lower contribution of scattered dose from the collimator system.
为了实现瓦里安 Halcyon 全乳照射的切线治疗技术，并将其与 Elekta Synergy Agility 计划进行比较。
对 20 例患者进行了两种可比的治疗计划，以实现剂量覆盖和正常组织保护。使用滑动窗口技术（Eclipse/Halcyon）对切线场内场治疗计划（Pinnacle/Synergy）进行了重新规划。使用门户剂量学和 ArcCHECK 体模进行了特定于计划的 QA。使用改良的 CIRS 体模评估了两种系统上的治疗剂量分布和治疗交付。
单次剂量 2.67 Gy 的平均 MU 数分别为 Halcyon 和 Synergy Agility 计划的 515 MU 和 260 MU。两个治疗单元的均匀性指数和剂量覆盖相似。计划特异性 QA 显示实测计划与计算计划之间具有良好的一致性。所有 Halcyon 计划均通过了门户剂量学 QA（3%/2mm），100%点通过，ArcCheck QA（3%/2mm）通过了 99.5%。使用 CIRS 体模测量累积治疗和成像剂量，结果表明 Halcyon 计划对健侧乳房的剂量更低。
对于瓦里安 Halcyon，实现了与 Elekta Synergy 设备相似的计划质量。对于 Halcyon 计划，由于 Halcyon MLC 的叶片间传输更少，以及准直器系统散射剂量的贡献更低，治疗野对健侧乳房的剂量贡献甚至更低。
