OPTIMIZATION OF DOSE DISTRIBUTIONS FROM INTRAOPERATIVE APPLICATORS

由于术中使用的单次分数剂量很高 在放射治疗中，尽量减少高剂量区域是很重要的。这些地区 是由于光子准直器和光子准直器之间的散射关系 喷头系统。它们可能是非对称的，原因是 不对称涂抹器设计，或到 喷头系统，导致喷头中心略偏 与加速器的中心射线不同。这些剂量分布 可以通过使用最优域来优化到预定的标准 施加器和电子能量的每个组合的大小。对.的使用 非对称准直器可以进一步校正剂量的不均匀 由于不对称设计、施胶器斜角或 喷头未对准。

Due to the high single fraction doses employed in intraoperative radiotherapy, it is important to minimize areas of high dose. These areas arise due to the scattering relationship between the photon collimators and the applicator system. They may be non-symmetric due to either an asymmetric applicator design, or to manufacturing tolerances of the applicator system resulting in the center of the applicator to be slightly different than the central ray of the accelerator. These dose distributions can be optimized to predetermined criteria by the use of an optimum field size for each combination of applicator and electron energy. The use of asymmetric collimators can further correct for nonuniformity in the dose distribution due to asymmetric design, applicator bevel angle, or applicator mis-alignment.