Treatment planning and verification tools for adaptive radiation therapy

放射治疗试图通过向肿瘤提供致命剂量的电离辐射来破坏癌细胞，同时最大限度地减少对周围健康组织的辐射。典型的放射治疗方案在一系列每日治疗部分中在数周的时间段内递送。当前放射治疗技术不是最佳的一个重要领域是它们没有考虑治疗期间解剖结构的变化。具体地，由于生理过程（诸如呼吸和消化），内部解剖结构将在治疗递送期间移动和变形。肿瘤缩小，周围组织的结构可以从一个治疗部分到下一个治疗部分发生变化。不考虑这些变化的治疗计划可能无法在肿瘤控制和保留健康组织之间实现最佳平衡。

Radiation therapy seeks to destroy cancerous cells by delivering a lethal dose of ionizing radiation to the tumour while minimizing the irradiation of surrounding healthy tissue. A typical radiation treatment regimen is delivered over a period of weeks in a series of daily treatment fractions. One important area in which current radiation therapy techniques are not optimal is that they do not account for the changes in anatomy during therapy. Specifically, internal anatomy will move and deform during treatment delivery due to physiological processes such as respiration and digestion. Tumours shrink and the configuration of the surrounding tissue can change from one treatment fraction to the next. Treatment plans which do not account for these changes may not achieve an optimum balance between tumour control and sparing healthy tissue.