Conference Paper

Ant colony system for the beam angle optimization problem in radiotherapy planning: a preliminary study

Sch. of Lfe Sci. & Technol., UESTC, Chengdu, China
DOI: 10.1109/CEC.2005.1554871 Conference: Evolutionary Computation, 2005. The 2005 IEEE Congress on, Volume: 2
Source: IEEE Xplore

ABSTRACT Intensity-modulated radiotherapy (IMRT) is being increasingly used for treatment of malignant cancer. Beam angle optimization (BAO) is an important problem in IMRT. In this paper, an emerging population-based meta-heuristic algorithm named ant colony optimization (ACO) is introduced to solve the BAO problem. In the proposed algorithm, a multi-layered graph is designed to map the BAO problem to ACO, and a heuristic function based on the beam's-eye-view dosimetrics (BEVD) score is introduced. In order to verify the feasibility of the presented algorithm, a clinical prostate tumor case is employed, and the preliminary results demonstrate that ACO appears more effcient than genetic algorithm (GA) and can find the optimal beam angles within a clinically acceptable computation time.

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