Niemierko A, Goitein M
Department of Radiation Oncology, Massachusetts General Hospital, Boston 02114.
Int J Radiat Oncol Biol Phys. 1993 Jan;25(1):135-45. doi: 10.1016/0360-3016(93)90156-p.
A model for calculating normal tissue complication probability in response to therapeutic doses of radiation is presented.
The model which we call the "critical volume model" is based on a concept of functional subunits defined either structurally (e.g., nephrons) or functionally, and an assumption that normal tissue complication probability is fully determined by the number or fraction of surviving functional subunits composing an organ or tissue. The essential features of the model are that it takes into account variations in tissue radiosensitivity and architecture of an organ for a single patient and for a patient population, and predicts the normal tissue complication probability under conditions of 3-dimensional inhomogeneity of the dose distribution. The model can be used for Integral Response, or "parallel," organs (where all functional subunits are performing the same function in parallel and the output of the organ is the sum of the outputs of the functional subunits and for Critical Element, or "serial," organs (where damage to one functional subunit results in an expression of damage for the whole organ). The model combines into one compact scheme new concepts and several ideas and models which have been previously developed by other investigators.
The behavior of the model is presented and discussed for the example of the kidney, with clinical nephritis as the functional endpoint.
The model has the potential to be a useful tool for evaluation and optimization of 3-dimensional treatment plans for a variety of types of normal tissues.
提出一种用于计算正常组织对治疗性辐射剂量反应的并发症概率的模型。
我们称之为“临界体积模型”的该模型基于在结构上（如肾单位）或功能上定义的功能亚单位概念，以及正常组织并发症概率完全由构成器官或组织的存活功能亚单位的数量或比例决定的假设。该模型的基本特征是，它考虑了单个患者和患者群体中组织放射敏感性和器官结构的变化，并预测了剂量分布三维不均匀情况下的正常组织并发症概率。该模型可用于整体反应器官（即所有功能亚单位并行执行相同功能且器官输出为功能亚单位输出之和的器官），以及关键元件器官（即一个功能亚单位受损会导致整个器官出现损伤表现的器官）。该模型将其他研究者先前提出的新概念、几种观点和模型整合到一个紧凑的方案中。
以临床肾炎为功能终点，展示并讨论了该模型在肾脏示例中的行为。
该模型有可能成为评估和优化各种类型正常组织三维治疗计划的有用工具。
