Analysis of the registration deviation between CT and CBCT images with different breathing rates and motion amplitudes in the state of free breathing
10.3760/cma.j.cn113030-20210728-00278
- VernacularTitle:自由呼吸频率与运动幅度对CT与CBCT图像配准偏差分析
- Author:
Xing WEI
1
;
Xin XU
;
Long BAI
;
Pan GONG
;
Renming ZHONG
Author Information
1. 四川大学华西第二医院肿瘤放化疗科/出生缺陷与相关妇儿疾病教育部重点实验室，成都 610041
- Keywords:
Free breathing;
Image registration;
Target volume;
Cone-beam CT
- From:
Chinese Journal of Radiation Oncology
2022;31(7):628-632
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To quantify the registration deviation between CT and cone-beam computed tomography (CBCT) images with different breathing rates and motion amplitudes under free breathing state.Methods:Using the QUASAR respiratory motion phantom, breathing rate and motion amplitude in the superior-inferior (SI) direction were changed to simulate free breathing motion under different states. The CT and CBCT images were acquired under different breathing rates and motion amplitudes, and static states, then the registration errors between CT and CBCT images and CT target volume were obtained and subject to quantitative analysis.Results:Using the static CT image as a reference, the changes in breathing rate exerted no significant effect on the registration error when the motion amplitude was constant. When the motion amplitude was 0.5, 1.0, 2.0, and 3.0 cm, the average registration errors were (0.213±0.020), (0.351±0.009), (0.654±0.010), and (0.972±0.022) cm, respectively. When the motion amplitude was 0.5 and 1.0 cm, the CT target volume varied from -16.92% to 18.78%. When the motion amplitude was 2.0 and 3.0 cm, the CT target volume changed from -16.44% to 81.78%.Conclusions:The changes in breathing rate under free-breathing state has no significant effect on the registration error between CBCT and CT images. When the motion amplitude is 0.5 and 1.0 cm, the CT target volume changes and the registration errors are small. When themotion amplitude is 2.0 and 3.0 cm, the registration errors exceed 0.5 cm and the CT target volume changes may exceed 20%.
