SU-E-T-717: Research on the Inhomogeneous Correction Algorithm Based on Monte Carlo Simulation

作者：L Li, Z Zhang, Bo Xia · 发表于：Medical Physics · 年份：2011 · DOI：10.1118/1.3612679 · 研究领域：Radiative Heat Transfer Studies

Purpose: Batho is one of inhomogeneous correction algorithms which has high correction accuracy in homogeneous tissue, but has lower correction accuracy in cavum and the interface between different density tissues. In this paper, the database of dose distribution with every kinds of different density tissues combination by Monte Carlo simulation is built up for the purpose of development for fast and accurate dose calculation method. Methods: The MC simulation models are built as follow. Model 1: in 30cm×30cm×30cm cube phantom full of one homogeneity tissue. In module 2:1cm×1cm×1cm cube inhomogeneous tissue is put in the central axis (0,0,0.5),(0,0,1.5,)…(0,0,29.5) (each down 1cm) of model 1 respectively. These phantoms are segmented into 0.2cm × 0.2cm × 0.2cm volumes. For simplicity, the inhomogeneous tissue of human body is classified to typical tissues (water, bone etc.) by electron densities. The dose distribution of homogeneous tissue and inhomogeneous tissue is simulated by MC in model 1 and model 2.All dose value is normalized to the point (0,0,1.5). Then database of dose distribution relative error between dose distribution of mode 2 and mode l could be established. At any point p, the destiny change along the primary ray path judged by program firstly. Batho algorithm is used in uniform region. In the interface between different tissues and inside cavity, the dose value will be corrected by the database of relative error. Results: Comparing with the correction result...