Chen Jing
Radiation Protection Bureau, Health Canada, 775 Brookfield Road, Ottawa K1A 1C1, Canada.
Radiat Prot Dosimetry. 2006;121(4):358-63. doi: 10.1093/rpd/ncl056. Epub 2006 May 12.
In the literature, no conversion coefficients are available for use in radiological protection of the embryo and foetus against external exposure to photons. This study used the Monte-Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to external photon fields. Monoenergetic photons ranging from 50 keV to 10 GeV were considered. The irradiation geometries included antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT), and isotropic (ISO). At each of these standard irradiation geometries, absorbed doses to the foetal brain and body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months. Photon fluence-to-absorbed-dose conversion coefficients were estimated for the four prenatal ages.
在文献中，没有可用于胚胎和胎儿外照射光子辐射防护的转换系数。本研究使用蒙特卡罗代码MCNPX来确定母亲暴露于外照射光子场时胚胎和胎儿的平均吸收剂量。考虑了能量范围从50 keV到10 GeV的单能光子。照射几何条件包括前后位（AP）、后前位（PA）、侧位（LAT）、旋转位（ROT）和各向同性位（ISO）。在这些标准照射几何条件下，分别计算了8周龄胚胎以及3、6或9月龄胎儿的胎儿脑部和身体的吸收剂量。估算了四个产前年龄的光子注量到吸收剂量的转换系数。
