치료계획용 컴퓨터를 이용한 부정형조사면의 선량분포에 관한 실험

An Experimental Dosimetry of Irregularly Shaped Fields Using Therapeutic Planning Computer

The authors have intended to measure intrinsic dose distribution by Farmer dosimeter in irregularly shaped fields such as L.M. and T shape models in order to determine dose inhomogeneity in those models. We made 2 off-axis points in each model and measured the depth dose at 1.5, 5 and 9 cm below surface. The results showed 1~3% dose discrepancy between 2 points. We also measure the depth dose by geometric approximation and computer calculation in those models and came to the conclusion that computer calculation using Clarkson's principle is simpler and the measurements are closer to the ideal data obtained by the experiment in three models of irregularly shaped fields than those of geometric approximation method.