Abstract：Objective Most patients undergoing vertebral radiotherapy have metastatic lesions, and the patients are mostly
immobile. The IGRT is able to correct the errors in time and achieve the therapeutic effect as they perform poorly in positional
fit due to various reasons such as pain. In clinical practice, there are no scan conditions directed at vertebral radiotherapy in
the conventional scan conditions of the accelerator. We studied the application of CBCT with different scanning conditions in
the treatment of IMRT. Methods A total of 23 patients with thoracic and lumbar lesions requiring radiotherapy had 304 CBCT
corrections. Each patient was positional verified using CBCT with two scanning conditions before radiotherapy was administered.
The parameters of scanning condition A were: collimator S20, light limiting cylinder F1, rotation degree 210°, detection panel
position S, frame rotation speed 360°/min, general scanning dose 0.6 mGy丨 the parameters of scan condition B were: collimator
M20, light limiting cylinder F1, rotation degree 360°, detection panel position M, general scanning dose 22 mGy. After CBCT
scans, after CBCT scans, the pose error data of the left-right (X-axis), head-foot (Y-axis), and ventral-dorsal (Z-axis) directions were
obtained from the patient’s two scans, and the error values were subjected to paired t-tests. Results In X, Y, Z direction, P>0.05,
according to the level of α = 0.05, there was no difference between CBCT with two scanning parameters in the vertebral IMRT.
However, the scanning time of the parameter A was shorter than that of parameter B, and the scan dose was significantly lower than
parameter B, which reduced the risk of low dose radiation. Conclusion The recommended scanning conditions for vertebral IGRT
treatment with parameter A could shorten the patient treatment pose and image tracking time and reduce the additional irradiation
dose generated by the patient receiving the image-guided portion of the treatment, while ensuring the consistent treatment accuracy.
黄成剑，李勇，杨金鑫，王先良. CBCT不同扫描参数在椎体图像引导调强放疗中的应用研究[J]. 中国医疗设备, 2021, 36(7): 60-63.
HUANG Chengjian, LI Yong, YANG Jinxin, WANG Xianliang. Study on the Application of Different Scanning Parameters of CBCT in Vertebral Image
Guided Intensity-Modulated Radiotherapy. China Medical Devices, 2021, 36(7): 60-63.
