用新鲜子宫及阴道标本检测曼彻斯特系统剂量分布  

Dose Measurement of Manchester System in Specimens of Uterus and Vagina

作　　者：叶伟军[1] 陈昆田[1] 何智纯[1] 曹新平[1] 卢杰[1] 黄绍敏[1] 王骅[2] 辜英杰 

机构地区：[1]中山医科大学肿瘤防治中心放射治疗科,广东广州510060 [2]中山医科大学肿瘤防治中心妇科,广东广州510060 [3]广东省辐射剂量鉴定站,广东广州510080

出　　处：《癌症》2001年第11期1305-1308,共4页Chinese Journal of Cancer

摘　　要：目的:检测宫颈癌近距离放疗中曼彻斯特系统剂量分布,为质量控制及质量保证提供依据。方法:特制一双面模板,把插植针及软管放入槽内,夹入慢感光X光片,检测放射源的到位精度。把软管放入检测孔,电离室放在离源10cm处空气中测量放射源的活度。水箱中不放标本测量A点及其外1cm、2cm、3cm剂量,然后放入子宫及直管施源器,电离室放在A点外1cm、2cm、3cm处,执行2个后装治疗计划,测量各点的剂量,并与TPS推算值比较。结果:经检测,软管施源器的源到位误差约2～3mm,通过调整施源器的长度,源的到位精度在1mm内。源的顶端与插植针焊接点的距离约5mm。源活度实测与TPS推算值相差5.4%,各点的剂量学实测与TPS推算值关系复杂,水箱内无标本时实测偏差在6%内,放入子宫标本时测量误差最大为13.86%。A点外1cm、2cm、3cm剂量比值与理想平方反比定律比值偏差最大为8.01%。结论:TPS推算值与实测值偏差较小,说明目前临床使用的曼彻斯特系统结果可信。Objectives: In order to measure the Manchester system of cervical carcinoma in brachytherapy and provide the data to quality control and quality assurance. Methods: Firstly, a two side template was made. Insert implanting needles and soft tubes into the troughs, sandwich the slow sensitive film to check the accuracy of source position. Secondly, put the soft tube into the check hole and ion chamber in the air 10 cm away from the source to calibrate the source active. In the water box the doses of A point 1 cm, 2 cm, 3 cm outside was measured. Then put the uterus and straight tube applicators into the water box. The doses of A point 1 cm, 2 cm, 3 cm outside were measured through processing two treatment plans. These data were compared with the calculation of TPS. Results: Through checkout the soft tubes source position errors were about 2-3 mm, and they were adjusted less than 1 mm by adjusting applicators. The source top was 5 mm away from the welding points in implant needles. The deviation between measurement and TPS calculation was 5.4%. The relationship between the points measured values and calculation by TPS is complex. Without specimen their deviation was less than 6%, with specimen their maximum deviation was 13.86%. Conclusions: The deviation between the calculation of TPS and the measured values is small, so Manchester System is believed clinically.

关 键 词：宫颈肿瘤 近距离放疗 曼彻斯特系统 慢感光胶片 电离室 

分 类 号：R730.4[医药卫生—肿瘤]