摘要
[目的]探讨影响鼻咽癌(NPC)放疗精确度的因素。[方法]两组技师每组12人,分别操纵西门子和飞利浦的模拟定位机和直线加速器,每人独立完成1例NPC病人的面膜固定,模拟定位,拍定位片。然后在模拟机下重复摆位及拍片,再到直线加速器上摆位及拍射野验证片。观察重复摆位时激光十字线与摆位标记点的重合情况,以及按解剖骨性标记定位片分别与验证片和重拍的模拟片的误差情况。[结果]①重复摆位时激光十字线与面膜上的摆位标记点模拟机下重复得较好,而治疗机下较差。②骨性标记误差范围在0～6mm之间,两组骨性标志误差在模拟机之间或者治疗机之间的比较总体没有差异(P>0.05);而在模拟机和治疗机之间的比较却有统计学的差异(P<0.05)。[结论]重复摆位体表标记重合较好时骨性标记也可能存在较大的误差,从模拟机到治疗机之间摆位误差较大,而在模拟机之间的重复摆位误差较小。
[Purpose] To explore the factors influencing the accuracy in radiotherapy positioning for nasopharyngeal carcinoma patients. [Methods] Twenty-four radiotherapeutic technicians were divided into 2 groups to manipulate Siemens or Philips X-ray simulators and linear accelerators respectively. Every technician was required to independently complete the patient immobilization. X-ray simulation and acquisition of simulation film; to repeat at X-ray simulation and acquisition of the second simulation film and to verify the film at linear accelerator. The coincidence between skin markers and laser coordinates.and the patient setup error in comparison of simulation film vs. repeated film as well as simulation film vs. verification film according to bone anatomy markers were compared. [Results]① The skin markers were in good accordance with laser coordinates for patient setup in X- ray simulator. However, the reproducibility of patient setup was bad for linear accelerator. ②The discrepancy of the bone anatomy marker was about O～6 mm. There was no statistical significance for bone anatomy maker error in paient setup comparison of 2 groups between different X-ray simulators or between different linear accelerators（P〉0.05）. However, significant statistical difference was found between X-ray simulator and linear accelerator, [Conclusion] The discrepancy of patient setup according to the shift of bone anatomy marker may be obvious even if the skin markers are in good accordance with laser coordinates. Significant setup error was fimnd between X-ray simulator and linear accelerator, while little setup error was found between different X-ray simulators.
出处
《肿瘤学杂志》
CAS
2005年第5期331-333,共3页
Journal of Chinese Oncology
关键词
鼻咽肿瘤
放射疗法
放疗技师
nasopharyngeal neoplasms, radiotherapy
radiation therapist
