Verification of position accuracy and repeatability of a self-designed vaginal cervical immobilization device: a water phantom study(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2023年第11期
- Page:
- 1327-1331
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Verification of position accuracy and repeatability of a self-designed vaginal cervical immobilization device: a water phantom study
- Author(s):
- HU Jian1; WANG Luzhou1; CHEN Xin2; CHEN Jiayu2; CHANG Sheng1; XU Ximing2
- 1. Department of Radiation Oncology, Renmin Hospital of Wuhan University, Wuhan 430060, China 2. the Third Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060, China
- Keywords:
- Keywords: vaginal cervical immobilization device self-designed water phantom verification
- PACS:
- R318；R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2023.11.002
- Abstract:
- Abstract: Objective To verify the position accuracy and repeatability of a novel self-designed vaginal cervical immobilization device using KVKV and CBCT based on water phantom. Methods The novel vaginal cervical immobilization device consists of in vivo and in vitro systems. The in vitro one consists of a scale fixed with the base plate, a vacuum bag and an abdominal heat shrinkable film, and the in vivo consists of a cylindrical vaginal fixator and a vaginal tube containing 4 titanium alloy marker. The CT image obtained with a scanning thickness of 1.25 cm and a 40 cm×30 cm×20 cm phantom was imported into the Monaco (v5.11) system. Four marked points were taken as isocentric to perform KVKV and CBCT verifications at the linac accelerator. Each marked point was scanned in 5 groups of two modes (20 images each) to verify its position accuracy and repeatability. The differences between the two verification modes were compared. Results The total vertical, longitudinal, lateral displacements of KVKV and CBCT were (0.10±0.05) cm vs (0.09±0.06) cm, (0.11±0.06) cm vs (0.1±0.05) cm, (-0.10±0.06) cm vs (-0.10±0.05) cm, respectively, and there was no statistical difference between the two verification modes (P>0.05).?he maximum absolute value of the setup deviation was 0.2 cm (frequency ≤ 17.5%), and the absolute values of the rest of the deviation were ≤±0.1 cm.?he difference of setup deviation between KVKV and CBCT was ≤±0.1 cm. Conclusion The self-designed vaginal cervical immobilization device has good position accuracy and repeatability. KVKV verification has the advantages of higher resolution, smaller artifacts and shorter time as compared with CBCT. It is recommended to use KVKV for verification. If necessary, CBCT should be used for local assistant verification.
Last Update: 2023-11-24