Application value of CIVCO headrest in positioning of head tumor radiotherapy
10.3969/j.issn.1671-8348.2025.09.025
- VernacularTitle:CIVCO头架在头部肿瘤放疗摆位中的应用价值研究
- Author:
Rongrong QU
1
;
Qianqian ZHENG
;
Jing CAO
;
Zihong WANG
Author Information
1. 首都医科大学石景山教学医院/北京市石景山医院放疗科,北京 100043
- Keywords:
head tumors;
positioning error;
CIVCO Uni frame adjustable angle headrest;
domestic inte-grated board;
PTV external expansion boundary
- From:
Chongqing Medicine
2025;54(9):2138-2141,2146
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the positioning errors,required planning target volume(PTV)outer expansion boundary and three-dimensional displacement of two different positioning fixation devices CIVCO Uni-frame carbon fiber adjustable angle head frame and domestic integrated board in radiotherapy for the pa-tients with head tumor,and to investigate the application value of CIVCO headrest in the positioning of head tumor radiotherpay.Methods The clinical data of 82 patients with head tumors who underwent radiotherapy in this hospital from January to December 2023 were analyzed retrospectively.The patients were divided into the adjustable angle head frame group and integrated plate group,41 cases in each group.Both groups were fixed with U-shaped thermoplastic head film.Radiotherapy was performed by using ELEKTA infinity linear accelerator.The cone beam computed tomography(CBCT)image guidance was used,combined with bone reg-istration and manual calibration to obtain the patient positioning errors in three directions:X axis,Y axis and Z axis.The positioning error data of each CBCT was recorded;based on the PTV outward expansion boundary formula(2.5∑+0.7σ),the PTV outward expansion boundaries required by the two fixation devices in all di-rections for the treatment of head tumors were calculated;the 3-dimensional spatial displacement was calculat-ed based on the patient's single radiotherapy positioning error.Results The absolute positioning errors in the X,Y,and Z directions of the adjustable angle head frame group were 0.13(0.07,0.22),0.16(0.16,0.27),0.10(0.05,0.18)cm respectively,which in the integrated board group were 0.14(0.07,0.24),0.18(0.08,0.32),0.09(0.04,0.10)cm respectively.The absolute error of the Y direction in the adjustable angle head frame group was smaller than that of the integrated board group(P=0.006),and the difference in the relative error between the two groups was not statistically significant(P＞0.05).According to the PTV expansion formula,the calculated expansion boundaries of the X,Y,and Z directions in the adjustable head frame group were 0.24,0.30,0.22 cm,which in the integrated plate group were 0.21,0.36,0.21 cm,respectively.The three-dimensional space comprehensive positioning error value could be calculated by the formula calculation using the positioning error values in three directions.The mean values of the three-dimensional space positio-ning errors of the adjustable angle headstock group and domestic integrated plate group were 0.320 cm and 0.340 cm respectively,there was no statistically significant difference between the two groups.Conclusion The absolute error in Y direction and the median value of three-dimensional displacement of the CIVCO adjustable angle head rest are smaller than those of the domestic integrated plate,which is worthy of clinical promoted applica-tion if conditions permit.
