Liu Chihray, Simon Thomas A, Fox Christopher, Li Jonathan, Palta Jatinder R
Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, FL 32610-0385, USA.
Int J Radiat Oncol Biol Phys. 2008;71(1 Suppl):S89-92. doi: 10.1016/j.ijrobp.2007.07.2392.
Understanding the characteristics of a multileaf collimator (MLC) system, modeling MLC in a treatment planning system, and maintaining the mechanical accuracy of the linear accelerator gantry head system are important factors in the safe implementation of an intensity-modulated radiotherapy program. We review the characteristics of an Elekta MLC system, discuss the necessary MLC modeling parameters for a treatment planning system, and provide a novel method to establish an MLC leaf position quality assurance program. To perform quality assurance on 40 pairs of individual MLC leaves is a time-consuming and difficult task. In this report, an effective routine MLC quality assurance method based on the field edge of a backup jaw as referenced in conjunction with a diode array as a radiation detector system is discussed. The sensitivity of this test for determining the relative leaf positions was observed to be better than 0.1 mm. The Elekta MLC leaf position accuracy measured with this system has been better than 0.3 mm.
了解多叶准直器（MLC）系统的特性、在治疗计划系统中对MLC进行建模以及保持直线加速器机架头部系统的机械精度是安全实施调强放射治疗计划的重要因素。我们回顾了医科达MLC系统的特性，讨论了治疗计划系统所需的MLC建模参数，并提供了一种建立MLC叶片位置质量保证程序的新方法。对40对单独的MLC叶片进行质量保证是一项耗时且困难的任务。在本报告中，讨论了一种有效的常规MLC质量保证方法，该方法以备用钳口的射野边缘为参考，并结合二极管阵列作为辐射探测器系统。观察到该测试确定相对叶片位置的灵敏度优于0.1毫米。用该系统测量的医科达MLC叶片位置精度优于0.3毫米。
