原体照射機構による二軸振子照射の線量分布と線量評価

抄録

A pair of pendel irradiation technique is the method of combining two pendel irradiation with rectangular field on the different rotation axis, and is aimed to produce a high dose region like a tumor area. Meanwhile, conformation technique is able to give a maximum dose to the deformed tumor selectively with the minimum dose to the surrounding normal tissues. It above two technique were combined, the drawbacks of each method would be compensated each other, and more reasonable dose distribution required in clinical case would be obtained. In this paper, experimented results and the technique of pendel irradiation combined with conformation mechanism in order to produce a concaved high dose region required for the whole pelvis irradiation of carc. of the cervix uteri were discribed. Dose distribution were obtained phantom experiment and the contour of high dose region were agree well with expected target area. Dose variation along the rotation axis was less than 5 percent. Dose homogeneities on the vertical and sagital plane were acceptable level for the clinical porpose. The differences of Tissue Peak Ratio between Calculated value and experimented value were 2 percent at the most. No particular differences were recognized on the method of dose estimation, tumor localization compared with the other technique. This technique is commonly applied for the treatment of carc. of the cervix uteri in our department for a year.