External locating of moving targets for 3D IMRT using parallax method

Jian-Ning Han, Peng Yang, Lu Zhang

COMPUTER MODELLING & NEW TECHNOLOGIES 2014 18(5) 257-262

School of Information and Communication Engineering, North University of China, 3 Xue Yuan Road, Taiyuan, China

Due to the complexity of intensity modulated radiotherapy, it is difficult to meet the current situation of treatments which require real time locating of moving target. In this paper, we propose a new method based on parallax method using external label to locate the moving target. A column test-piece is used to simulate the human body structure for data analysis. A defect model for human body target is implanted inside the test-piece, which is the moving target. Based on the parallax method, the depth of the defect can be obtained by using the two images captured before and after the test-piece moves a short distance. The possible errors which affect the test results are analysed. The effects of errors can be reduced by adjusting the system parameters. The results show that the parallax method is a simple but efficient approach, which can be used for locating moving target in intensity modulated radiotherapy.