三维近距离放射治疗计划系统的研究

The develcpment of a 3D brachytherapy treatment planning system

近距离放射治疗是临床综合治疗肿瘤的有效组成部分。由于历史的及其自身的复杂性等原因 ,它的发展滞后于外照射 ,国内的应用和研究都落后于国外。因此我们开展了关于三维近距离治疗计划系统的研究。提出了基于图像的三维近距离治疗计划的研究和实施方案 ,在SGI工作站上建立了计划系统的基本框架和窗口界面 ,重点研究和实现点源的插植剂量分布的计算、等剂量线的二维和三维显示、体积—剂量直方图对计划的评估等 ,适用于源或施源器的放置前计划和放置后计划。

Brachytherapy dose prescription and treatment method is now playing lag behind the state-of-the-art in external beam therapy.This paper introduces a program based on a SGI graphics workstation to plan the loading or stereotactic implantation of radioactive seeds.The treatment planning system,using data from the pre-treatment diagnostic CT scan or MRI scan,contours target areas on sequential images creats a 3-dimensional taget volume,and is based on a dose algorithm of Tg-43 formalism.The treatment isodose contour is generated at each scanplane,reconstructed saggital and coronal views,and overlaid on the corresponding target contour for 3-dimensional coverage visualization.Volume dose histograms are generated for the target and neighboring normal structures.Two orthogonal digitally reconstructed projecting images are also provided to identify virtual source positions superimposed on for fluoroscopy guided loading applicators and sources.