Bagne F R, Samsami N, Dobelbower R R
Department of Radiation Therapy, Medical College of Ohio, Toledo 43699.
Med Phys. 1988 Jul-Aug;15(4):530-7. doi: 10.1118/1.596204.
In intraoperative radiation therapy, it is critical to reduce the radiation contamination outside the useful field by as much as physically feasible. Additionally, a uniform dose is clinically desirable across the tumor volume. A study of the Medical College of Ohio applicators indicates that the radiation contamination outside the field can be as high as 18% of the central axis dose. The effects of the photon collimator setting on the magnitude and energy of the radiation contamination are discussed and means are presented for reducing this unwanted radiation. The dose nonuniformity across the field is found to be virtually independent of the photon collimator setting and is shown to be mostly due to the transparent applicator wall. The clinical significance of the findings is discussed.
在术中放射治疗中，尽可能在物理上可行的范围内减少有用射野之外的辐射污染至关重要。此外，临床上期望肿瘤体积内剂量均匀。俄亥俄医学院施源器的一项研究表明，射野之外的辐射污染可能高达中心轴剂量的18%。讨论了光子准直器设置对辐射污染的大小和能量的影响，并提出了减少这种有害辐射的方法。发现射野内的剂量不均匀性实际上与光子准直器设置无关，并且显示主要是由于施源器透明壁所致。讨论了这些发现的临床意义。
