CAJ | 학술논문

非均匀组织等效水厚度修正是研究质子放射治疗的重要组成部分,利用蒙特卡罗Fluka2011.2程序模拟了不同能量(50—250 MeV)的质子束入射到不同介质中的输运过程,总结出了在不同介质中质子束初始能量与质子束Bragg峰深度关系,并拟合出质子束在介质中的等效水厚度修正公式.结果表明,对不同能量的质子束入射到非均匀组织中,通过拟合公式计算出Bragg峰深度值与Fluka模拟的质子束Bragg峰的位置相差在1 mm之内.如果建立起介质和水的Bragg峰比与电子密度比关系的数据库,该公式有可能用于临床上的质子放射治疗的剂量计算中.
비균균조직등효수후도수정시연구질자방사치료적중요조성부분,이용몽특잡라Fluka2011.2정서모의료불동능량(50—250 MeV)적질자속입사도불동개질중적수운과정,총결출료재불동개질중질자속초시능량여질자속Bragg봉심도관계,병의합출질자속재개질중적등효수후도수정공식.결과표명,대불동능량적질자속입사도비균균조직중,통과의합공식계산출Bragg봉심도치여Fluka모의적질자속Bragg봉적위치상차재1 mm지내.여과건립기개질화수적Bragg봉비여전자밀도비관계적수거고,해공식유가능용우림상상적질자방사치료적제량계산중.
@@@@The inhomogeneous tissue equivalent water thickness correction method is an important part of research in proton radiotherapy. In this paper, we simulate the transport processes of a high-energy proton beam being injected into the water and other materials using Monte-Carlo multi-particle transport code Fluka, and according to the energy deposition distribution we obtain the depth of the Bragg peak when the protons are injected into different materials. Then we fit an analytic formula (R=αE p0 ) to the relationship between initial proton energy and the depth of the proton Bragg peak in different materials. It is found that for the different energies of proton beam being injected into non-uniform organization, the difference between the Bragg peak depth from fitting and the depth of the proton beam Bragg peaks from Fluka program is less than 1 mm. If we can establish a database about the relationship of Bragg peak ratio between medium and water, with electron density, then the equivalent water thickness correction method will be able to applied to the dose calculation of for homogeneous medium in proton therapy.