Chen G T, Spelbring D R, Pelizzari C A, Balter J M, Myrianthopoulos L C, Vijayakumar S, Halpern H
Michael Reese/University of Chicago, Center for Radiation Therapy, IL 60637.
Int J Radiat Oncol Biol Phys. 1992;23(1):153-63. doi: 10.1016/0360-3016(92)90555-v.
In 3-dimensional treatment planning, beam's eye view (BEV) is used as an interactive tool to define portal entry angles that exclude critical structures while fully encompassing the target volume. With beam's eye view volumetrics (BEV volumetrics), the volume of intersected normal tissues is also calculated and is used as a quantitative tool to choose portal orientations that minimize normal tissue volumes irradiated. The axial beam entry angle and a polar angle (relative to the patient longitudinal axis) are specified to define the central axis orientation. Using BEV volumetrics, we have studied the quantities of normal tissues irradiated when treating tumors in the abdomen, thorax, and pelvis. The reduction of normal tissue irradiated is a strong function of site and patient-specific tumor size and location. Volumetrics combined with BEV is found to be useful in treatment planning because it (a) provides quantitative information needed in rationally choosing portal entry angles, (b) provides a near interactive speed approach to understanding the relative merits of different multiple field plans, and (c) compliments the information provided by the more time-consuming generation of dose volume histograms.
在三维治疗计划中，射野方向观（BEV）被用作一种交互式工具，用于定义射野入射角度，该角度在完全覆盖靶区体积的同时排除关键结构。借助射野方向观容积测量法（BEV容积测量法），还可以计算相交正常组织的体积，并将其用作一种定量工具，以选择使受照正常组织体积最小化的射野方向。通过指定轴向射野入射角和极角（相对于患者纵轴）来定义中心轴方向。利用BEV容积测量法，我们研究了腹部、胸部和盆腔肿瘤治疗时受照正常组织的量。受照正常组织的减少在很大程度上取决于部位以及患者特定的肿瘤大小和位置。发现容积测量法与BEV相结合在治疗计划中很有用，因为它（a）提供了合理选择射野入射角所需的定量信息，（b）提供了一种近乎交互式的快速方法来理解不同多野计划的相对优点，并且（c）补充了由耗时更长的剂量体积直方图所提供的信息。
