摘要
Abstract
Objective To study the effect of carbon fiber postural fixation plate on radiotherapy dose of cervical cancer.Methods The carbon fiber postural fixation plate model was created in the RayStation plan-ning system,and the difference of attenuation coefficient between the model plate in the planning system and the real plate in the actual measurement was compared to verify the accuracy of the position fixing plate mod-el.A total of 10 patients with cervical cancer were selected,and the plate-free plan was designed on the CT im-age without the fixed plate model,and the dose was calculated.After the plate-free plan was completed,the plan was transplanted to the CT image with the fixed plate model to obtain the plate plan,and the dose was calculated.The dosimetric differences of target volume(PTV)and organ at risk(OAR)between the plate-free plan and the plate plan were compared.Two ArcCHECK verification phantoms were established in the RayStation planning system,which were the ArcCHECK verification phantom with the postural fixation plate model and the ArcCHECK verification phantom without the postural fixation plate model.The 10 cervical cancer plans were transplanted into two verification phantoms for dose calculation.Under the Xinhua accelera-tor,ArcCHECK was placed on the postural fixation plate to perform the validation plan,and the effect of the postural fixation plate model in the planning system on the gamma passing rate of the verification plan was compared.Results For the accuracy of the position fixation plate model was created in the planning system:the deviation(d)of the attenuation coefficient obtained in the planning system and the actual measurement is less than 0.3％.For the cervical cancer plan:compared with the plate without plan,the dose of PTV and OAR in the plate with plan was significantly lower.The average dose of PTV was about 1％lower,and the degree of OAR was different,ranging within 3％.For cervical cancer plan verification:the gamma pass rate of the plate model verification plan was significantly higher than that of the platefree plan model verification plan,and the pass rates of 3 mm/3％and 2 mm/2％were increased by 0.69％and 1.50％,respectively.Conclusion The carbon fiber postural fixation plate has a certain effect on the radiotherapy dose of cervical cancer patients.In order to ensure the accuracy of the target dose,it is recommended to add the postural fixation plate model in the plan design.关键词
碳纤维/体位固定板/板模型/宫颈癌/放疗剂量/伽马通过率Key words
carbon fiber/posture fixing plate/plate model/cervical cancer/radiotherapy dose/gamma pass rate分类
医药卫生
