人眼晶状体是一种辐射敏感器官,建立精细的人眼模型对于精确评估晶状体的受照剂量及辐射风险非常重要。该文基于中国成年男性眼睛的特征参数建立了精细眼模型,该模型包含眼睑、巩膜、脉络膜、视网膜、晶状体、虹膜、角膜、玻璃体和房水9个主要结构。在此精细眼模型的基础上,利用MCNP模拟程序计算多种照射情形下晶状体的电子剂量转换系数,并与相关文献中的结果进行对比。结果表明:当电子能量在0.6~1.2 MeV之间时,计算结果与其他文献中的结果差异较大,相对偏差最高可达98%,该模型为准确评估中国成年男性晶状体剂量提供了参考。
The human eye lens is sensitive to radiation. Thus, detailed eye models are needed to accurately assess the dose and radiation risk for the eye lens. A detailed eye model was build based on the characteristic parameters of Chinese adult males. The eye model includes nine main structures for the eyelids, scleral, choroid, retina, lens, iris, cornea, vitreous body and aqueous humor. The model was then used in an MCNP code to calculated the eye lens absorbed dose conversion coefficients for electrons for various irradiation conditions. The results compared with other studies show that the relatively deep anterior chamber of the Chinese male eye results in significant differences in the absorbed dose for electron energies between 0.6-1.2 MeV with a maximum relative difference of 98%. The detailed eye model in this paper provides a tool for accurate assessments of eye lens doses of Chinese adult males.
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