Iwasaki A
School of Allied Medical Sciences, Hirosaki University, Aomori, Japan.
Phys Med Biol. 1995 Mar;40(3):383-91. doi: 10.1088/0031-9155/40/3/004.
A method is reported that evaluates the wall correction factor (Awall)water of an ionization chamber using measured data. The method needs a revised type of tissue-air ratio (TARcav) that should be measured with the ionization chamber. An experimental study has been carried out for 60Co gamma-rays using zero-area TARcav data extrapolated from non-zero-area TARcav data using the extrapolation method developed by Bjärngard and Petti. Using this technique, it is found that the value of (Awall)water for an ionization chamber has a deviation of -0.1% to -0.4% as compared with the Monte Carlo results. An experimental study has also been carried out using a published set of 60Co traditional tissue-air ratio (TAR) data assuming TARcav = TAR.
报道了一种使用测量数据评估电离室壁修正因子（Awall）水的方法。该方法需要一种经过修正的组织空气比（TARcav）类型，应使用电离室进行测量。利用Bjärngard和Petti开发的外推方法，从非零面积TARcav数据外推得到零面积TARcav数据，对60Coγ射线进行了实验研究。使用该技术发现，电离室的（Awall）水值与蒙特卡罗结果相比偏差为-0.1%至-0.4%。还使用一组已发表的60Co传统组织空气比（TAR）数据进行了实验研究，假设TARcav = TAR。
