| 吴钦宏,李雪南,刘春玲,朱宝全,田丽红,张清文,竺萌,秋晞,王婵,李高峰.应用锥形束CT评价最终等中心标记法定位头颈部肿瘤的摆位误差[J].中华放射医学与防护杂志,2012,32(3):301-303 |
| 应用锥形束CT评价最终等中心标记法定位头颈部肿瘤的摆位误差 |
| Evaluation of setup errors for head-and-neck cancer localized with final isocenter marking method via cone beam CT |
| 投稿时间：2011-11-09 |
| DOI：10.3760/cma.j.issn.0254-5098.2012.03.020 |
| 中文关键词: 锥形束CT 最终等中心标记法 摆位误差 CT模拟 |
| 英文关键词:Cone beam CT Final isocenter marking method Setup error CT simulation |
| 基金项目: |
|
| 摘要点击次数: 3558 |
| 全文下载次数: 2283 |
| 中文摘要: |
| 目的 应用千伏级锥形束CT(kV CBCT)评价头颈部肿瘤图像引导放疗的摆位误差。方法 选取2009年3月至2011年10月的256例行调强放疗的头颈部肿瘤患者,采用头颈肩面罩固定体位,最终等中心标记法定位,配有LAP可移动式激光定位系统的Philips PQS CT 或 Philips Brilliance CT Big Bore进行CT扫描。CT图像通过网络传输给Varian Eclipse治疗计划系统,用来进行勾画靶区和设计计划。在治疗前使用Varian iX 直线加速器的机载影像系统(OBI)行kV CBCT扫描和配准,得出左右、头脚和前后3个方向的摆位误差。结果 473组摆位误差数据呈高斯分布,3个方向的平均误差分别为(-0.6±1.3)、(0.5±1.6)和(0.9±1.7) mm,使用公式M=2.5Σ+0.7δ计算外放边界分别为2.4、2.4和3.4 mm。其中,Big Bore组的288组数据的计算外放边界分别为2.0、2.1和1.7 mm。结论 最终等中心标记法的摆位误差优于参考点标记法,同时为CTV外放PTV的边界提供了有效的依据。 |
| 英文摘要: |
| Objective To evaluate the setup errors of image guided radiation therapy (IGRT) for head-and-neck cancer using kilovoltage cone beam CT(kV CBCT).Methods 256 patients with head-and-neck cancer were treated with intensity modulated radiation therapy (IMRT) from March 2009 to October 2011. All patients were immobilized with head-and-neck mask and localized with final isocenter marking method using the Philips PQS CT or Philips Brilliance CT Big Bore scanners, which were equipped with LAP movable laser systems. The CT images were transferred to a Varian Eclipse V8.6 workstation for contouring and planning. A kV cone-beam CT scans was acquired, and registered before the treatment for every patient on a Varian iX linear accelerator via OBI system. The setup errors in the right-left (RL), superior-inferior (SI), and anterior-posterior (AP) directions were recorded.Results The setup errors for the 473 datasets followed a Gaussian distribution. The systematic errors ± random errors in the RL, SI and AP were(-0.6±1.3),(0.5±1.6) and (0.9±1.7) mm, respectively. The planning target volume (PTV) margins were calculated respectively as 2.4,2.4 and 3.4 mm according to the formula of M=2.5Σ+0.7δ. The margins of 288 sets of data using the Big Bore CT scanner were calculated as 2.0,2.1 and 1.7 mm, respectively.Conclusions The setup errors using final isocenter marking method are smaller than those using reference point marking method. The result derived from this retrospective study could be used to set the margin between CTV and PTV. |
| HTML 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|