Optimization of seed source position with genetic algorithm in prostate implantation

前立腺癌の代表的な治療法に、前立腺内に放射性の密封小線源を刺入する放射線治療法がある。この治療では、疾患部に適切な線量を加えるとともに、尿道や周辺臓器への線量投与を抑えるように線源を配置する必要がある。本論文では、遺伝的アルゴリズムを用いて前立腺へ適切に密封小線源を配置するアルゴリズムを検討した。In the brachytherapy for the prostate cancer the calculation of the optimum location of seed sources is very difficult. The least square approach is sometimes not effective, because this therapy uses so many seeds and needles. In this paper we applied the genetic algorithm for deciding the location of seed source and we evaluated the parameter which required in the optimization. The results of simulation showed that the dose distribution is very sensitive to the parameter value being selected