剂量引导精确放射治疗中三维评价算法设计及实现

Realization of 3D Evaluation Algorithm in Dose-guided Radiotherapy

针对临床剂量学验证中二维评价方法只能反映每张平片上剂量分布情况,并根据剂量引导精确放疗系统中三维剂量验证需求设计算法实现对三维剂量分布的比较。根据公式,在Visual C++控制台下实现剂量偏差、位置偏差及γ分析三维评价算法。设计两个计划进行算法验证:计划1为方野照射等效水,用于验证算法的正确性;计划2为适形野照射仿真头模,用于验证算法的实用性。结果表明,计划1中,对剂量偏差,容许值范围内通过率为100%;对位置偏差和γ分析,容许范围内通过率为100%,容许边界值处为100±7.7%。计划2中,3种算法通过率分别为88.35%、100%和95.07%。这说明该算法可用于剂量引导精确放疗系统中实现三维剂量分布的评价。

Abstract： 3D evaluation algorithm instead of 2D evaluation method of clinical dose verification is highly needed for dose evaluation in Dose-guided Radiotherapy. 3D evaluation algorithm of three evaluation meth- ods, including Dose Difference, Distance-To-Agreement and 7 Analysis, was realized by the tool of Visual C＋＋ according to the formula. Two plans were designed to test the algorithm, plan 1 was radiation on e- quivalent water using square field for the verification of the algorithm＇s correctness~ plan 2 was radiation on the emulation head phantom using conformal field for the verification of the algorithm＇s practicality. For plan 1, the dose difference, in the tolerance range has a pass rate of 100%, the Distance-To-Agree- ment and 7 analysis was of a pass rate of 100% in the tolerance range, and a pass rate of 99±1% at the boundary of range. For plan 2, the pass rate of algorithm were 88.35%, 100%, 95.07% for the three e- valuation methods, respectively. It can be concluded that the 3D evaluation algorithm is feasible and could be used to evaluate 3D dose distributions in Dose-guided Radiotherapy.