加速器典型照射条件下靶外组织受照剂量测量与分析

摘要/Abstract

摘要：

目的掌握加速器典型放射治疗条件下患者照射野靶外组织受照剂量水平，为患者防护方案的优化和精确治疗计划的制定与实施提供实验依据。方法以Varian TrueBeam 6 MV直线加速器为辐射源，采用Phantom Laboratory公司生产的RANDO 110成人女性仿真模体，在10 cm×10 cm标准照射野、SSD 100 cm条件下对脐下腹部区域累积照射600 cGy，用LiF（Mg、Cu、P）热释光探测器测量模体乳腺、肝脏、胃、膀胱及性腺等关键组织器官受照剂量。采用Excel 2019建立数据库，SPSS 21.0软件进行统计分析，Mann-Whitney检验（U检验）比较照射野左右两侧人体躯干从胸部到盆部的纵向剂量水平。结果照射野靶外邻近器官受照剂量最高，其中左右侧性腺平均剂量为723.00 mGy（为照射野中心剂量的12.05%），膀胱平均剂量为409.00 mGy（6.82%），肝脏剂量为46.40 mGy（0.77%）。照射野靶外远端器官受照剂量相对较低，左右侧乳腺平均剂量分别为10.20 mGy（0.17%）和11.01 mGy（0.18%）。照射野左右两侧的剂量分布差异无统计学意义（Z=1.132，P>0.05）。结论放射治疗导致的靶外组织受照不可避免但不容忽视，照射野靶外邻近组织器官的受照剂量甚至可能达到放射损伤阈值，临床实践中应采取个性化防护策略，最大限度降低靶外受照剂量与辐射风险。

关键词: 放射治疗, 靶外组织, 患者剂量, 放射防护, 仿真模体, 直线加速器

Abstract:

Objective To investigate the dose of out-of-field tissues under typical linear accelerator radiotherapy conditions，and to provide experimental evidence for optimizing patient protection strategies and refining treatment planning. Methods A Varian TrueBeam 6 MV linear accelerator served as the radiation source，and an adult female anthropomorphic phantom RANDO 110 manufactured by Phantom Laboratory was used to simulate the patient in this study. A 10 cm×10 cm standard field was applied to the abdomen below navel with SSD of 100 cm，delivering a total dose of 600 cGy. LiF（Mg，Cu，P） thermoluminescent detectors were used to measure the absorbed doses in critical out-of-field tissues，including the breast，liver，stomach，bladder and gonads. A database was established using Excel 2019，and SPSS 21.0 software was utilized for statistical analysis. The Mann-Whitney test（U test） was employed to compare the longitudinal dose levels from the chest to the pelvis in the human torso on both the left and right sides of the radiation field. Results The highest out-of-field doses were observed in organs adjacent to the radiation field. The mean doses to the left and right gonads were 723.00 mGy（12.05% of the target dose），and the mean bladder dose was 409.00 mGy（6.82%）. The liver received a dose of 46.40 mGy（0.77%）. In contrast，doses to remote organs were considerably lower than that of above，with mean left and right breast doses of 10.20 mGy（0.17%） and 11.01 mGy（0.18%），respectively. There was no statistically significant difference in the distribution between the left and right sides dose（Z=1.132，P>0.05）. Conclusion Radiation exposure of out-of-field tissues during radiotherapy is inevitable and non-negligible. Doses to organs close to the target-field may approach thresholds for radiation-induced damage. Therefore，individualized protection strategies should be implemented in clinical practice to minimize out-of-field exposure and associated radiation risks.

Key words: Radiotherapy, Out-of-field tissues, Patient absorbed dose, Radiation protection, Anthropomorphic phantom, Linear accelerator

中图分类号:

R148

姜雯雯, 顾浩琰, 于润秋, 冯泽臣, 王宏芳, 马永忠. 加速器典型照射条件下靶外组织受照剂量测量与分析. [J]职业与健康, 2026, 42(1): 17-21.

JIANG Wenwen, GU Haoyan, YU Runqiu, FENG Zechen, WANG Hongfang, MA Yongzhong. Measurement and analysis of out-of-field tissue dose under typical accelerator radiotherapy conditions. [J]OCCUPATION AND HEALTH, 2026, 42(1): 17-21.

图/表 6

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序号	编号	模体TLD探测位置与照射野边缘水平距离（cm）	模体TLD探测位置对应的体表位置	吸收剂量（mGy）	关注点剂量与照射野中心剂量的比率（%）
1	R-01	20	右乳腺外侧	10.15	0.17
2	R-02	20	右乳腺下缘	10.76	0.18
3	R-03	20	右乳腺内侧	12.11	0.20
4	L-03	20	左乳腺外侧	9.57	0.16
5	L-02	20	左乳腺下缘	9.84	0.16
6	L-01	20	左乳腺内侧	11.20	0.19
7	2301	7	肝脏	46.40	0.77
8	2302	7	胃与肠道	33.83	0.56
9	2303	7	胃与肠道	41.43	0.69
10	2304	7	腹部浅层组织右侧	44.16	0.74
11	2305	7	腹部浅层组织中央	44.21	0.74
12	2306	7	腹部浅层组织左侧	40.08	0.67
13	3201	1	右侧性腺	803.10	13.39
14	3202	1	子宫	628.38	10.47
15	3203	1	左侧性腺	642.06	10.70
16	3204	1	膀胱右侧	427.80	7.13
17	3205	1	膀胱中部	474.96	7.92
18	3206	1	膀胱左侧	323.28	5.39

序号	编号	模体TLD探测位置与照射野边缘水平距离（cm）	模体TLD探测位置对应的体表位置	吸收剂量（mGy）	关注点剂量与照射野中心剂量的比率（%）
1	R-01	20	右乳腺外侧	10.15	0.17
2	R-02	20	右乳腺下缘	10.76	0.18
3	R-03	20	右乳腺内侧	12.11	0.20
4	L-03	20	左乳腺外侧	9.57	0.16
5	L-02	20	左乳腺下缘	9.84	0.16
6	L-01	20	左乳腺内侧	11.20	0.19
7	2301	7	肝脏	46.40	0.77
8	2302	7	胃与肠道	33.83	0.56
9	2303	7	胃与肠道	41.43	0.69
10	2304	7	腹部浅层组织右侧	44.16	0.74
11	2305	7	腹部浅层组织中央	44.21	0.74
12	2306	7	腹部浅层组织左侧	40.08	0.67
13	3201	1	右侧性腺	803.10	13.39
14	3202	1	子宫	628.38	10.47
15	3203	1	左侧性腺	642.06	10.70
16	3204	1	膀胱右侧	427.80	7.13
17	3205	1	膀胱中部	474.96	7.92
18	3206	1	膀胱左侧	323.28	5.39