Analysis of effects of CT slice thickness on target dose distribution in Cyberknife radiotherapy using chest phantom(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2023年第6期
- Page:
- 667-671
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Analysis of effects of CT slice thickness on target dose distribution in Cyberknife radiotherapy using chest phantom
- Author(s):
- ZHAO Rui1; CAO Yangsen2; GAO Xingxin1; WANG Zhenyue1; LI Sha1; TIAN Zhongze1
- 1. Department of Radiation Oncology, the 940th Hospital of Joint Logistics Force, Lanzhou 730050, China 2. Department of Radiation Oncology, Changhai Hospital, Naval Medical University, Shanghai 200433, China
- Keywords:
- Keywords: chest phantom Cyberknife CT slice thickness treatment plan dose
- PACS:
- R318；R815
- DOI:
- DOI:10.3969/j.issn.1005-202X.2023.06.002
- Abstract:
- Abstract: Objective To study the effects of CT slice thickness on the target dose distribution in Cyberknife radiotherapy. Methods The conventional CT locating and reconstruction were carried out on the chest phantom for the simulated tumors TUMOR01-TUMOR05 with CT slice thicknesses of 1.0-5.0 mm. For each simulated tumor, the Cyberknife radiotherapy plans of the CT sequences with different slice thicknesses were made with the fixed Auto-Shells, prescription dose, prescription dose line and collimator, and the calculation results were recorded. Then the treatment plans with different CT slice thicknesses were transplanted to the treatment plan with 1.0 mm slice thickness, and the dosimetric changes after plan transplantation were recorded. The changes in the radiotherapy target area before and after transplantation of radiotherapy plans of different CT slice thicknesses were compared. Results Except that the Dmax of the TUMOR01 target area showed a weak correlation to the CT slice thickness (|r|=0.20), the Dmax of the TUMOR02-TUMOR05 target areas, and the Dmin, CI, nCI and coverage of TUMOR01-TUMOR05 target areas had strong correlations to the CT slice thickness (|r|>0.70). The Dmin and the coverage of TUMOR01-TUMOR05 target areas were negatively correlated to the CT slice thickness, while the Dmax, CI and nCI were positively correlated to the CT slice thickness, and their significance levels were different. The Dmin, nCI and coverage of the TUMOR01 target area were changed significantly with the slice thickness larger than 2 mm, and their changed ranges were 9.89-15.29 Gy, 0.19-0.76 and 11.44%-29.94%, respectively. Conclusion CT slice thickness affects the target dose distribution in Cyberknife radiotherapy significantly, and it is extremely significant for the smaller tumor.
Last Update: 2023-06-28