Computer Simulation of Radioactive Source Delivery Process in Nasopharyngeal Carcinoma Brachytherapy

Brachytherapy is one of the major means of nasopharyngeal carcinoma treatments. The process of radioactive source delivery and the distribution of radioactive dose are two pivotal factors of brachytherapy planning. A new method for simulation of the two factors was proposed in this paper. Firstly, the CT images of the nasopharyngeal tissues were segmented and the 3D models of nasopharyngeal tissues were reconstructed. Then the process of cylindrical radioactive source delivery was simulated with virtual endoscopy method. A new computing method of 3D radioactive source delivery path planning based on Ta-chih Lee's thinning algorithm was proposed. Finally, the dose distribution of cylindrical radioactive source was simulated by Monte Carlo method. Based on this method, computer simulation of nasopharyngeal carcinoma brachytherapy process can be realized and it will be of great help to the design of nasopharyngeal carcinoma brachytherapy plan.