Rose Mark S, Tirpak Lena, Van Casteren Kristin, Zack Jeff, Simon Tom, Schoenfeld Andreas, Simon William
Sun Nuclear Corporation, 3275 Suntree Blvd, Melbourne, Florida, 32940, USA.
Med Phys. 2020 Jul;47(7):3153-3164. doi: 10.1002/mp.14153. Epub 2020 Apr 27.
The SRS MapCHECK , a recently developed patient-specific quality assurance (PSQA) tool for end-to-end testing of stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT), was evaluated in a multi-institution study and compared with radiochromic film.
The SRS MapCHECK was used to collect data on 84 SBRT or SRS PSQA plans/fields at nine institutions on treatment delivery devices (TDD) manufactured by Varian and Elekta. PSQA plans from five different treatment planning software (TPS) were selected and executed on TDDs operating at beam energies of 6 and 10 MV with and without a flattening filter. The patient plans were all VMAT except for ten conformal arc therapy fields. The plans were selected to encompass a range of size and tumor sites including brain, lung, spine, abdomen, ear, pancreas, and liver. Corresponding radiochromic film data was acquired in 50 plans/fields. Results were evaluated using gamma analysis with absolute dose criterion of 3% global dose-difference (DD) and 1 mm distance-to-agreement (DTA).
The mean 3% DD/1 mm DTA Gamma pass rate of SRS MapCHECK in comparison to film was 95.9%, whereas comparison of SRS MapCHECK to the treatment planning software was 94.7%. 80% of SRS MapCHECK comparisons against film exceed 95% pass rate, and about 30% of SRS MapCHECK comparisons against film exceed 99% pass rate. To maintain good agreement between SRS MapCHECK and film or TPS, authors recommend avoiding plans with a modified modulation complexity score (MMCS) <0.1 arbitrary units (a.u.). In the examples presented, this coincides with avoiding plans with a mu/dose limit of >3 µ/cGy.
Stereotactic radiosurgery MapCHECK has been validated for PSQA for a variety of clinical SRS/SBRT plans in a wide range of treatment delivery conditions. The SRS MapCHECK comparison with film demonstrates near-equivalence for analysis of patient-specific QA deliveries comprised of small field measurements.
SRS MapCHECK是一种最近开发的用于立体定向放射外科（SRS）和立体定向体部放射治疗（SBRT）端到端测试的患者特异性质量保证（PSQA）工具，在一项多机构研究中进行了评估，并与放射变色胶片进行了比较。
使用SRS MapCHECK在9家机构中收集了84个SBRT或SRS PSQA计划/射野的数据，这些数据来自Varian和Elekta生产的治疗输送设备（TDD）。从5种不同的治疗计划软件（TPS）中选择PSQA计划，并在运行于6和10 MV束流能量、有或无均整器的TDD上执行。除了10个适形弧治疗射野外，所有患者计划均为容积调强弧形放疗（VMAT）。选择这些计划以涵盖一系列大小和肿瘤部位，包括脑、肺、脊柱、腹部、耳部、胰腺和肝脏。在50个计划/射野中获取了相应的放射变色胶片数据。使用绝对剂量标准为3%全局剂量差异（DD）和1 mm距离一致性（DTA）的伽马分析对结果进行评估。
与胶片相比，SRS MapCHECK的平均3% DD/1 mm DTA伽马通过率为95.9%，而与治疗计划软件相比为94.7%。80%的SRS MapCHECK与胶片的比较通过率超过95%，约30%的SRS MapCHECK与胶片的比较通过率超过99%。为了保持SRS MapCHECK与胶片或TPS之间的良好一致性，作者建议避免使用调制复杂度评分（MMCS）<0.1任意单位（a.u.）的计划。在给出的示例中，这与避免使用μ/剂量限值>3 μ/cGy的计划一致。
立体定向放射外科MapCHECK已在广泛的治疗输送条件下针对各种临床SRS/SBRT计划的PSQA进行了验证。SRS MapCHECK与胶片的比较表明，对于由小射野测量组成的患者特异性QA输送分析，两者近乎等效。
