鼻咽癌发泡胶个体化塑形与标准化头枕放疗体位固定精确度比较

The research of accuracy immobilized using individualized polyurethane scaling agent compared to positioning foam with standard plastics pillow in the radiotherapy of nasopharyngeal carcinoma

目的 应用KV级CBCT研究发泡胶个体化塑形在鼻咽癌放疗体位固定上的优势.方法 采用发泡胶个体化塑形和标准化树脂头枕,联合头颈肩热塑面罩对鼻咽癌患者进行体位固定.随机选取两种固定方法患者在治疗过程中每周给予1次CBCT扫描,采集三维方向靶区区域和单独颈椎区域的摆位误差数据并配对t检验,应用2.5∑＋0.7σ分别算出整体和颈部外扩边界.结果 标准化头枕组整体和单独颈部在左右、上下、前后方向摆位线性误差分别为（-0.27±1.33）、（-0.31±1.50）、（0.54±0.90） mm和（-0.59 ±2.76）、（-0.11 ±2.23）、（0.66±1.60） mm,对应外扩边界为3.28 mm、3.64 mm、1.86 mm和6.17 mm、5.17 mm、3.52 mm;发泡胶组相应为（-0.44±0.87）、（0.18±1.06）、（-0.13 ±0.72）mm和（-0.07±1.58）、（0.04±2.11）、（-0.03±1.31）mm,对应外扩边界为2.07、2.46、1.71 mm和3.57、5.03、3.16 mm.标准化头枕组整体和单独颈部在左右、上下、前后方向摆位线性误差比较P =0.315、0.011、0.000和0.045、0.630、0.002.结论 采用头颈定位泡沫垫对鼻咽癌进行体位固定效果优于传统的标准定形枕,特别是在颈部固定有了较大提升;另外颈部外扩边界远大于鼻咽部外扩边界,建议鼻咽区域和颈部区域分开定义外扩边界.

Objective To study the superiority of polyurethane foam sealing agent immobilization with KV-CBCT for the patients with nasopharyngeal carcinoma （NPC）.Methods 36 NPC patients were divided into two groups.Group A was immobilized using standard plastics pillow with the head-and-neck thermoplastic masks,and so do individualized polyurethane foam sealing agent pillow as group B.CBCT was weekly carried out weekly,and the setup errors of the head and neck position （axial （x,y,z）） were analyzed by paired t-test.The marginal was caculated using 2.5∑ ＋ 0.7σ.Results On x-,y-,z-axial,the average setup errors values of head and neck position were （-0.27 ± 1.33） am,（-0.31 ± 1.50） mm,（0.54±0.90） mm and （-0.59±2.76） mm,（-0.11 ±2.23） mm,（0.66± 1.60） mm;and the marginal were 3.28 mm,3.64 mm,1.86 mm and 6.17 mm,5.17 mm,3.52 mm,respectively in Group A;with （-0.44 ±0.87） mm、（-0.18 ± 1.06） mm、（0.13 ±0.72） mm and （-0.07 ± 1.58） mm,（-0.04±2.11） mm,（0.03 ±1.31） mm,and 2.07 mm,2.46 mm,1.71 mm and 3.57 mm,5.03 mm,3.16mm,respectively in Group B.Compared with Group A to Group B,P value were 0.315,0.011,0.000 and 0.045,0.630,0.002 On x-,y-,z-axial.Conclusions The application of polyurethane foam sealing agent in the immobilization of NPC patients is better than standard plasthetics pillow,and especially for the positioning of neck.Compared to head position,the setup errors of neck are larger,so it is suggested to make the outer margin separately.