Clinical study of the effect of different CBCT scanning parameters on image quality and positioning error of cervical cancer
10.3969/j.issn.1672-8270.2024.11.004
- VernacularTitle:不同锥形束CT扫描参数对宫颈癌图像质量和摆位误差影响的研究
- Author:
Li LIU
1
;
Chengwei YE
;
Jianjun YUAN
;
Yingui LUO
;
Zhiyao LUO
;
Wei ZENG
;
Ling LI
;
Jiang LIU
Author Information
1. 德阳市人民医院肿瘤科 德阳 618000
- Keywords:
Cervical cancer;
Scanning parameter;
Cone beam computed tomography(CBCT);
Positioning error;
Image quality
- From:
China Medical Equipment
2024;21(11):18-24
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To assess the effects of the scanning parameters of cone beam computed tomography(CBCT)on image quality,positioning error and additional radiation dose for patients with cervical cancer after tube voltage was reduced,so as to explore scanning conditions that was suitable to patients with cervical cancer.Methods:Seventy-two patients with cervical cancer who received radiotherapy in Deyang People's Hospital from January 2020 to August 2022 were selected.According to different scanning parameters,they were divided into low-dose group A(120 kV,154.4 mAs),low-dose group B(120 kV,228.8 mAs)and conventional group[adopted business-supplied scan sequences(120 kV,675.8 mAs)].The CBCT scan image was obtained by decreasing the tube voltage and tube current,and reducing scanning angle.The registration results of positioning error of low-dose group A,B and conventional group on three directions included left and right(x-axis),head and foot(y-axis)and abdominal and back(z-axis)were respectively obtained,and the results were analyzed by variance analysis.The Catphan503 phantom of X-ray volumetric imaging(XVI)was used to measure the image quality of the corresponding 3 groups,and the further comparison was conducted.Results:There were no significant differences between the three groups in the scanning parameters on x,y and z axis directions for positioning error of patients with cervical cancer(P＞0.05).The scanning times of low-dose group A and B were approximately 1 minute,and the scanning time of conventional group was approximately 2 minutes.The noises of low-dose group A and B,and conventional group were respectively 36.51％,26.09％and 18.37％,and the radiation dose that was generated by CBCT image scanning in group A was correspondingly reduced.Conclusion:The reductions of scanning speed and collimator size of CBCT scanning parameters do not affect the positioning error and image quality,and it can decrease the scanning time and additional radiation dose of patients in undergoing radiotherapy.
