Evaluation of cost-effective ratio (imaging quality vs. radiation dose) of Varian cone beam CT based on figure of merit (FOM)
10.3760/cma.j.issn.0254-5098.2020.08.004
- VernacularTitle:基于品质因素评价瓦里安锥束CT成像质量与辐射剂量风险收益比
- Author:
Junyu LI
1
;
Hao WU
;
Jingxian YANG
;
Tingting LI
;
Songmao YU
;
Zihong LU
;
Meijiao WANG
;
Chenguang LI
;
Weibo LI
;
Yibao ZHANG
Author Information
1. 北京大学肿瘤医院暨北京市肿瘤防治研究所放疗科 恶性肿瘤发病机制及转化研究教育部重点实验室 100142
- From:
Chinese Journal of Radiological Medicine and Protection
2020;40(8):595-599
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze and compare the radiation dose and image quality of kilo-voltage cone beam CT systems on different Varian accelerator platforms, providing data to support clinical decisions on selecting optimal protocols for image-guided radiotherapy based on cost-effective ratio (image quality / radiation dose).Methods:The radiation dose and image quality of various CBCT systems and scanning protocols on Varian Edge, Truebeam and ix (new and old) LINACs were obtained using a CT dose index (CTDI) phantom combined with a CT ionization chamber and a Catphan604 phantom, respectively. Figure of merit (FOM) was used to evaluate the cost-effective ratio of the image guidance schemes.Results:Considerable inter-system varieties of FOMs were observed, varying from 0.65 (Image Gently-full trajectory) to 48.46 (Image Gently-half trajectory). The inter-protocol varieties were also large, where the mean±SD was 22.14±13.47.Conclusions:Considering the explicit inter-system and inter-protocol varieties, it is clinically favorable to evaluate the image guidance schemes based on machine-specific measurement. For instance, parameters and equipment with low CTDI w can be beneficial for dose-sensitive patients. High CNR regimen favors patients with high image quality requirements. For ordinary patients, cost-effective ratio in terms of FOM can be very helpful to guide the decision-making of clinical image-guided radiotherapy.
