Absorbed fractions for alpha-particles in tissues of cortical bone.
Absorbed fractions for alpha-particles in tissues of cortical bone.
复制标题
皮质骨组织中α粒子的吸收分数。
DOI：
10.1088/0031-9155/54/19/023
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发表时间：
2009
影响因子：
3.5
通讯作者：
Bolch,WesleyE
中科院分区：
文献类型：
--
作者：
Watchman,ChristopherJ;Bolch,WesleyE
寻骨α粒子放射核素是常见的健康物理危害。此外，它们正在考虑作为治疗性分子放射治疗应用的一种选择。目前的剂量模型没有考虑到ICRP第30号出版物中给出的α粒子吸收分数所显示的能量或骨位点依赖性。Stabin和Siegel （2003 Health Phys. 85 294-310）的模型表明，α粒子吸收部分依赖于能量，但与骨骼部位无关。在这项工作中，已经开发了一个基于弦的α粒子在皮质骨中传输的计算模型，该模型明确地说明了骨骼区域α粒子吸收部分的骨骼位置和粒子能量依赖。该模型考虑了能量沉积到三个目标：皮质内皮、哈弗氏间隙组织和皮质骨。皮质骨的路径长度分布给出于Beddoe（1977）。Med. Biol. 22 298-308)在吸收分数计算中提供了额外的传输区域。观察到不同骨骼部位吸收分数的显著差异。观察到该模型与ICRP出版物30中给出的吸收分数之间的差异，对于皮质骨表面源照射皮质内皮，其差异高达2.1倍。
Bone-seeking alpha-particle emitting radionuclides are common health physics hazards. Additionally, they are under consideration as an option for therapeutic molecular radiotherapy applications. Current dose models do not account for energy or bone-site dependence as shown by alpha-particle absorbed fractions given in ICRP Publication 30. Energy-dependent, yet bone-site independent, alpha-particle absorbed fractions have been presented by the models of Stabin and Siegel (2003 Health Phys. 85 294–310). In this work, a chord-based computational model of alpha-particle transport in cortical bone has been developed that explicitly accounts for both the bone-site and particle-energy dependence of alpha-particle absorbed fractions in this region of the skeleton. The model accounts for energy deposition to three targets: cortical endosteum, haversian space tissues and cortical bone. Path length distributions for cortical bone given in Beddoe (1977 Phys. Med. Biol. 22 298–308) provided additional transport regions in the absorbed fraction calculation. Significant variations in absorbed fractions between different skeletal sites were observed. Differences were observed between this model and the absorbed fractions given in ICRP Publication 30, which varied by as much as a factor of 2.1 for a cortical bone surface source irradiating cortical endosteum.