不规则形状电子射野的深度剂量和每监测单位剂量的计算。

Calculation of depth dose and dose per monitor unit for irregularly shaped electron fields.

作者信息

Khan F M, Higgins P D, Gerbi B J, Deibel F C, Sethi A, Mihailidis D N

机构信息

Department of Radiation Oncology, Fairview University Medical Center, Minneapolis, MN 55455, USA.

出版信息

Phys Med Biol. 1998 Oct;43(10):2741-54. doi: 10.1088/0031-9155/43/10/005.

DOI:10.1088/0031-9155/43/10/005

PMID:9814514

Abstract

A new dosimetric quantity, the lateral build-up ratio (LBR), has been introduced to calculate depth dose distribution for any shaped field. Factors to account for change in incident fluence with collimation are applied separately. The LBR data for a small circular field are used to extract radial spread of the pencil beam, sigma(r), as a function of depth and energy. By using the relationship between LBR, sigma(r), energy and depth, a formalism is developed to calculate dose per monitor unit for any shaped field. Criteria for lateral scatter equilibrium are also developed which are useful in clinical dosimetry.

摘要

一种新的剂量学量，即侧向积累比（LBR），已被引入用于计算任意形状射野的深度剂量分布。考虑准直引起的入射注量变化的因素被分别应用。小圆形射野的LBR数据用于提取笔形束的径向展宽σ(r)，作为深度和能量的函数。通过利用LBR、σ(r)、能量和深度之间的关系，建立了一种形式体系来计算任意形状射野的每监测单位剂量。还制定了侧向散射平衡的标准，这些标准在临床剂量学中很有用。