LINAC selection strategy based on quality of Varian cone beam CT image(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2019年第12期
- Page:
- 1367-1372
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- LINAC selection strategy based on quality of Varian cone beam CT image
- Author(s):
- LI Junyu1; WU Hao1; YANG Jingxian1; LI Tingting2; YU Songmao1; LU Zihong1; LI Weibo3; WANG Meijiao1; LI Chenguang1; ZHANG Yibao1
- 1. Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiation Oncology, Peking University Cancer Hospital & Institute, Beijing 100142, China; 2. 302 Military Hospital of Chinese PLA, Beijing 100039, China; 3. Institute of Radiation Medicine, Helmholtz Zentrum München-German Research Center for Environmental Health (GmbH), Ingolst?dter Landstr., Neuherberg 85764, Germany
- Keywords:
- Keywords: image-guided radiotherapy; kilo-voltage cone beam CT; linear accelerator; image quality
- PACS:
- R815.6；R318
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.12.001
- Abstract:
- Abstract: Objective To quantitatively analyze the features of different cone beam CT (CBCT) images for selecting the optimal LINAC for patients. Methods CatPhan604 phantom was used for evaluating the quality of the images of head, thorax and pelvis which were obtained by 4 CBCT mounted on an Edge, a TrueBeam, and 2 ix (ix New and ix Old). Results Of the 12 image sets, the best accurate CT number for the head, thorax and pelvis was observed on ix New, TrueBeam, and Edge, respectively, and the corresponding value was 5.69, 0.81, 6.74 HU, respectively. The best CT number linearity was found on ix New or ix Old (0.995), Edge (0.996), and Edge (0.997), respectively. Moreover, ix Old, Edge, and Edge or TrueBeam or ix Old had the minimal linear distance errors, which were 0.050, 0.075, 0.100 mm, respectively; and ix Old, Edge or TrueBeam, and Edge or ix New had the smallest angular errors, which were 0.075°, 0.050°, and 0.075°, respectively. For the head, thorax and pelvis, the best contrast resolution (7, 5, and 5 LP/cm, respectively) was achieved by ix Old, Edge, and Edge, respectively; and the best homogeneity (4.78, 20.19, and 4.63, respectively) was obtained by Edge, Edge, and Edge. The lowest noise for the head, thorax and pelvis was observed on Edge, ix New, and ix New, which were 27.53, 8.67, and 7.33, respectively; the best signal-to-noise ratio was observed on Edge, TrueBeam, and ix New, which were 83.17, 124.39, and 288.39, respectively; and the best contrast-to-noise ratio was observed on Edge, ix New, and ix New, which were 11.92, 41.42, and 51.47, respectively. No low contrast resolution was found in the head, while Edge or TrueBeam, and Edge achieved the best low contrast resolution (6.00 and 3.75) for thorax and pelvis. Conclusion Large inter-system varieties are observed among different CBCT systems. When choosing an appropriate machine for a special patient, imaging features should also be considered. For instance, LINAC with CBCT that can provide better CT number linearity and accuracy should be assigned for a patient undergoing adaptive radiotherapy, while machines with lower distance and angular errors should be chosen for patients having stereotactic radiotherapy.
Last Update: 2019-12-24