【摘要】 目的 :探讨基于影像引导验证的体部放射治疗(放疗)的靶区位置校正。方法 :对1 837例肿瘤放疗患者行负压真空袋塑型固定,放疗实施前利用加速器机载锥形束CT行靶区部位扫描,并与计划CT影像配准,获得两影像空间位置偏差,经影像确认后,偏差超过3 mm误差控制水准,给予位置校正。结果:胸部肿瘤中56.31%(531/943)影像引导后行位置校正,其中纵隔肿瘤组、肺癌组和乳腺癌组位置校正率分别为66.32%(191/288)、57.87%(250/432)和40.36%(90/223),3组间差异有统计学意义(P<0.05);上腹部肿瘤组54.33%(69/127)影像引导后行位置校正,与胸部肿瘤组差异无统计学意义;腹盆腔肿瘤组61.31%(347/566)影像引导后行位置校正,其中泌尿生殖系肿瘤组、宫颈癌组和直肠癌组位置校正率分别为67.27%(37/55)、64.54%(253/392)和47.90%(57/119),3组间差异有统计学意义(P<0.05);四肢肿瘤组54.23%(109/201)影像引导后行位置校正;胸部及上腹部肿瘤组、腹盆腔肿瘤组和四肢肿瘤组间差异有统计学意义(P<0.05)。结论:负压真空袋塑型放疗体位固定技术作为体部放疗主流的体位固定技术,提高了靶区位置精度,但仍有部分患者影像引导后需行位置校正,位置校正率由高到低依次为腹盆腔肿瘤、胸部和上腹部肿瘤、四肢肿瘤,采用负压真空袋进行体位固定时,应充分重视各部位的特点,提高位置精度。更多还原

【Abstract】 Objective:To investigate the position-correction of radiotherapy target in body basic on image-guiding. Methods:To compare the three-dimensional images between the CT images of TPS and the reconstructed images of the XVI system which dealing with the images from the cone-beam CT of the linear accelerator after scanning before the first three radiations of the radiotherapy,while the 1837 patients were immobilized with the minus pressure vacuum bags. The space errors that had exceeded 3 mm between the two images were corrected on line by the accelerator. The Chi-square test was been used in the statistical analysis process. Results:56.31% of the patients with tumors in the thorax were involved in the correction of the space errors of the target area after the image-guiding. The rates of the correction of the three groups that were the mediastinum tumor,lung cancer and breast cancer in the thorax were 72.32%,57.87%,40.36% respectively. There was distinct statistical significance among the three groups. 44.33% of the patients which the tumors in the upper abdomen were involved in the correction of the space errors of the target area after the image-guiding. There was no distinct statistical significance between the group of thorax and that of upper abdomen. 61.31% of the patients with tumors in the abdominal-pelvic were involved in the correction of the space errors of the target area after the image-guiding. The rates of the correction of the three groups that were the genitourinary tumor,cervix cancer and rectal cancer in the abdominal-pelvic were 67.27%,64.54%,47.90%,respectively. There was distinct statistical significance among the three groups. 54.23% of the patients with tumors in limbs were involved in the correction of the space errors of the target area after the image-guiding. There was also distinct statistical significance among the groups of thorax and upper abdomen,abdominal-pelvic and limbs. Conclusions:The immobilization technique with the minus pressure vacuum bag in the radiotherapy in body which is the mainstream,enhancing the space precision of the target area. But there is a proportion which need the correction of the space errors of the target area after the image-guiding. The rank of the rates of the correction of space error in radiotherapy in body in descent mode are abdominal-pelvic,thorax and upper abdomen and limbs. It should pay great attention to the characteristic of the different parts of the body when the immobilization been processed,to enhance the space precision of the target area.更多还原