Quality assurance test cases for stereotactic radiation therapy planning of multiple intracranial metastases
10.3760/cma.j.cn112271-20240509-00169
- VernacularTitle:颅内多发转移瘤立体定向放射治疗计划质量保证测试例应用研究
- Author:
Xiangyin MENG
1
;
Lang YU
1
;
Wenbo LI
1
;
Zhiqun WANG
1
;
Xin LIAN
1
;
Jiaxin WANG
1
;
Xiansong SUN
1
;
Lingxuan LENG
1
;
Bo YANG
1
;
Jie QIU
1
Author Information
1. 中国医学科学院 北京协和医学院北京协和医院放射治疗科，北京 100730
- Publication Type:Journal Article
- Keywords:
Multiple intracranial metastases;
Stereotactic radiotherapy;
Test case
- From:
Chinese Journal of Radiological Medicine and Protection
2025;45(1):31-36
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To present a set of clinically representative quality assurance (QA) test cases for stereotactic radiosurgery (SRT) plans of multiple intracranial metastases, in order to assess the plan quality and machine execution capabilities.Methods:Based on the clinical characteristics of multiple brain metastases, four groups of test cases with three target volumes (TVs), six TVs, nine TVs, and TVs near organs at risk (OARs) were designed. For these cases, SRT plans were developed, and plan quality was assessed using metrics including the Radiation Therapy Oncology Group conformality index (RTOG CI), gradient index (GI), homogeneity index (HI), and the volume of normal brain tissue receiving a dose of 24 Gy ( V24 Gy), which was defined as the volume enclosed by the 24 Gy isodose line around the Brain-PTV ( V24 Gy of Brain-PTV). Verification plans were generated for each test case, including the verification of point doses, planar doses (PD), and SRS MapCHECK (SMC) semiconductor matrix planar doses. Compared with the calculated result of the treatment planning system (TPS), the criteria for the γ analysis of planar doses were set at 1 mm/2% and 2 mm/2%. Results:For the four groups of test cases, the mean CI, GI, HI, and V24 Gy of Brain-PTV were 1.04±0.03, 3.79±0.40, 0.73±0.01 and (7.46±3.80) cm 3, respectively. The mean deviations of the point doses were 0.88%±0.98%, 1.47%±0.79%, 1.52%± 0.76%, and 1.17% ± 0.38%, respectively. The mean γ passing rates of the single fields for PDs were greater than 98% at 2 mm/2% and exceeding 96% at 1 mm/2%, and the mean γ pass rates of the SMC semiconductor matrix for PDs were 97.75% ± 2.31% and 99.33% ± 0.62%, at 1 mm/2% and 2 mm/2% respectively. Conclusions:The proposed QA test cases for SRT of multiple intracranial metastases allow for the effective assessments of the plan quality and machine execution capabilities and, thus, can assist various centers in clinical applications.
