锥形束CT引导下肺部SBRT两种摆位流程的误差比较.docVIP

精品论文 参考文献 锥形束CT引导下肺部SBRT两种摆位流程的误差比较 王成都 孙龙 翁邓胡 陈维军 许亚萍(浙江省肿瘤医院lt;浙江省胸部肿瘤重点实验室gt; 浙江杭州 310222） 　　【中图分类号】R445.4 【文献标识码】A【文章编号】1672-5085（2013）30-0108-02 　　【摘要】 目的 比较肺部SBRT患者因摆位流程不同而引起的误差。方法　22例肺部SBRT患者按摆位方式不同分为单线组与双线组进行治疗摆位。单线组仅在等中心点处勾画一组标记线；双线组为在患者体表的等中心点处和肚脐处分别勾画两组摆位标记线。对于双线组，治疗摆位时还需要移动治疗床，以检验加速器X轴激光线是否对准肚脐处的标记线。所有患者在摆位结束后治疗前，获取患者CBCT图像，利用图像配准软件和计划CT图像进行自动配准，然后由技师和物理师分别进行手动配准。记录移动误差，并对两种摆位流程的误差进行比较。结果　11例单线组患者共进行CBCT扫描80次；11例双线组患者共进行CBCT扫描66次。单线组在3个方向上的摆位误差为（2.58plusmn;1.77）mm，（3.76plusmn;3.45）mm，（1.64plusmn;1.25）mm，双线组患者在3个方向上（Lateral, Longitudinal, Vertical）的摆位误差为（2.70plusmn;2.13）mm,( 2.00plusmn;1.77)mm,(1.82plusmn;1.57)mm。结论　单线组和双线组的摆位误差平均值没有显著差异。双线组在头脚方向的摆位误差值小于单线组的对应数值。因此，在患者体表的肚脐处额外勾画一组标记线，并要求每次摆位时技师、医生和物理师同时在场可能有助于减少肺部SBRT患者的摆位不确定性。 　　【关键词】 肺癌 体部立体定向放射治疗 摆位误差 锥形束CT 　　【Abstract】 [objective] To compare setup errors in lung cancer SBRT due to different setup procedures.[method] 22 lung cancer cases were separated into two groups. Patients in single line group were marked at iso-center only. Patients were marked at both iso-center and navel in double line group. For double line group, couch was moved to double check whether the navel marker was overlap with laser. The CBCT images were retrieved to fusion with planning CT in Varian OBI system by both automatic method and manual method. Setup errors were recorded to the purpose of evaluating these two groups.[result] There were 80 setup data for single line group with 11 cases and 66 setup data for double line group with 11 cases . The setup errors in 3 direction for single line group were （2.58plusmn;1.77）mm，（3.76plusmn;3.45）mm，（1.64plusmn;1.25）mm。The setup errors in 3 direction (Lateral, Longitudinal, Vertical）for double line group were （2.70plusmn;2.13）mm,( 2.00plusmn;1.77)mm,( 1.82plusmn;1.57)mm。separately.[conclusion] There was no significant difference of average setup error in two groups. Double line group has less Setup errors in superior-inferior than a single group. Mark an extra line in navel ca