Deterministic Radiotherapy Dose Calculation Method

描述（由申请人提供）：临床需要开发准确有效的剂量计算方法，用于临床放射治疗计划。由于最近图像引导定位技术的进步和更精确的光束输送方法的发展，如强度调制放射治疗（IMRT），存在着大幅减少边际和提高剂量一致性的潜力。然而，目前临床使用的大多数剂量计算方法都采用近似值，这限制了它们的准确性和使用范围，特别是在存在异质性的窄光束时。因此，工业界正迅速向蒙特卡洛的临床应用迈进。然而，蒙特卡罗计算耗时，限制了其在临床治疗计划中的有效性。在第一阶段的研究中，一种新的确定性剂量计算方法解决了中性粒子和带电粒子的控制输运方程的微分形式，并在蒙特卡罗下对患者特异性前列腺和头颈部病例进行了验证。结果表明，该方法具有与蒙特卡罗方法相当的精度，并能提供更高的空间精度。同样，所提出的方法被证明比蒙特卡罗快得多，这可以转化为临床环境中更高的准确性。在第二阶段，将开发一个商业上可行的剂量计算系统，该系统可以集成到临床治疗计划系统中，比第一阶段原型具有多倍的性能提升。验证病例将由md安德森癌症中心执行，使用实验数据和回顾性患者计划。通过提供优于现有临床剂量计算方法的速度和准确性的组合，该II期产品有可能提高美国每年约65万名接受光子束放疗的患者的护理质量，并为全球更多的患者提供服务。此外，由于II期产品基于第一性原理数值方法，它最终可以适用于其他放射治疗方式。通过为医生提供更准确的剂量评估，II期研究有可能提高美国每年65万接受外束放疗患者的护理质量。通过普遍适用的算法，最终可以将结果迁移到其他放疗方式的临床治疗计划中。

DESCRIPTION (provided by applicant): A clinical need exists for the development of accurate and efficient dose calculation methods for clinical treatment planning in external beam radiotherapy. Due to recent advances in image guided localization techniques and the development of more precise beam delivery methods such as Intensity Modulated Radiation Therapy (IMRT), the potential exists to substantially reduce margins and improve dose conformity. However, most dose calculation methods in clinical use today employ approximations that limit their accuracy and scope of use, especially with narrow beams in the presence of heterogeneities. As a result, industry is moving rapidly towards the clinical adoption of Monte Carlo. However, Monte Carlo calculations are time consuming, limiting their effectiveness for clinical treatment planning. In the Phase I research, a novel deterministic dose calculation method, which solves the differential form of the governing transport equations for neutral and charged particles, was validated against Monte Carlo for patient specific prostate and head- and-neck cases. The results indicated that the proposed approach is as accurate as Monte Carlo, and can provide higher spatial precision. Similarly, the proposed approach was shown to be much faster than Monte Carlo, which can translate to improved accuracy in a clinical setting. In Phase II, a commercially viable dose calculation system will be developed which can be integrated into clinical treatment planning systems, with multi-fold performance gains over the Phase I prototype. Validation cases will be performed by M.D. Anderson Cancer Center, using both experimental data and retrospective patient plans. By providing a combination of speed and accuracy superior to existing clinical dose calculation methods, the Phase II product has the potential to improve quality of care for the approximately 650,000 patients receiving photon beam radiotherapy each year in the U.S., and for many more worldwide. In addition, since the Phase II product is based on first principles numerical methods, it can ultimately be adapted to other radiotherapy modalities. By providing physicians with more accurate dose assessments, the Phase II research has the potential to improve the quality of care for the 650,000 people receiving external beam radiotherapy in the United States each year. Through generally applicable algorithms, the resulting product can ultimately be migrated towards clinical treatment planning for other radiotherapy modalities.