| IMRT (Intensity Modulated Radiation Therapy) is a mainstream radiotherapy technology in the early21st century that can improve the gain of radiation therapy, thus the radiation dose will be concentrated on target volume within maximum limit, achieving the purpose of killing tumor cells while minimizing or avoiding exposure of normal tissues and organs at risk.The key step for IMRT is the inverse planning, and the purpose of IMRT inverse planning is to determine the ray type and energy, beam orientation and number, and so on [2]. Because of the complexity of the implementation for IMRT inverse planning, it usually needs computer aided inverse planning to solve the problem. The optimization of inverse planning is the core to realize the IMRT treatment planning, so it has important meaning to research on this problem.Research is supported by National Natural Science Foundation Project "IMRT inverse planning multi-objective optimization algorithm and its objective function (60872112)" funding. In this paper, the optimization of beam intensity distribution of IMRT has been studied.Major works of the dissertation are summarized as follows:1. Discussion on the development and hot spots of multi-objective optimization algorithm, and summary the optimization algorithms applied in IMRT;2. Discussion on the immune algorithm systematically, and put forward an improved immune clonal algorithm, through comparing the results with other evolutionary algorithms in five typical test functions, prove the feasibility and efficiency of this algorithm;3. The improved immune clonal algorithm is applied to the MRT inverse planning experimental platform, and through the actual example to verify the feasibility of it. |
