CAJ | 학술논문

目的探索CT值用于质子治疗计划系统计算质子入射能量的方法.方法通过分析Bethe-Block公式和质子射程计算公式,研究质子治疗能量范围(70～250 MeV)质子束在各种辐射等效材料中与水中的射程的比例关系.利用蒙特卡罗方法SRIM2008程序验证此比例系数存在恒值的可能性.通过Origin 8.0软件对此射程比例系数(Ci)和相应辐射等效材料的CT值进行指数函数拟合,研究CT值与射程比例系数的函数关系.分析CT测量原理和利用射程比系数将质子治疗的实际射程等效为水中的射程,从而反推入射质子所需的能量.结果质子治疗能量范围(70～250 MeV)质子束在辐射等效材料中的射程与此能量质子束在水中的射程的比值存在恒定的比例系数(Ci).CT值与射程比例系数相关(r=0.999).可以将特定能量质子在辐射等效材料中的射程等效为水中的射程.结论本研究利用机体各体积单元CT值与射程比例系数(Ci),精确计算实际照射肿瘤部位所需射程的水中等效射程,由水中等效射程计算出Bragg峰位落在肿瘤部位所需的入射质子束能量.本研究为CT技术用于质子治疗计划系统提出了一种新的探索.
목적 탐색CT치용우질자치료계화계통계산질자입사능량적방법.방법 통과분석Bethe-Block공식화질자사정계산공식,연구질자치료능량범위(70～250 MeV)질자속재각충복사등효재료중여수중적사정적비례관계.이용몽특잡라방법SRIM2008정서험증차비례계수존재항치적가능성.통과Origin 8.0연건대차사정비례계수(Ci)화상응복사등효재료적CT치진행지수함수의합,연구CT치여사정비례계수적함수관계.분석CT측량원리화이용사정비계수장질자치료적실제사정등효위수중적사정,종이반추입사질자소수적능량.결과 질자치료능량범위(70～250 MeV)질자속재복사등효재료중적사정여차능량질자속재수중적사정적비치존재항정적비례계수(Ci).CT치여사정비례계수상관(r=0.999).가이장특정능량질자재복사등효재료중적사정등효위수중적사정.결론 본연구이용궤체각체적단원CT치여사정비례계수(Ci),정학계산실제조사종류부위소수사정적수중등효사정,유수중등효사정계산출Bragg봉위락재종류부위소수적입사질자속능량.본연구위CT기술용우질자치료계화계통제출료일충신적탐색.
Objective To explore the application of CT value in calculating the proton incident energy in proton treatment planning system. Methods Bethe-Block formula and the formula for calculating the proton range were analyzed to study the correlation of the range of proton beam ( 70-250 MeV ) between a variety of radiation equivalent material and water. Procedure of Monte Carlo SRIM2008 was used to verify the possibility of a constant proportional coefficient of range ( Ci ). The proportional coefficient ( Ci ) of range in radiation-equivalent material and the CT value were fitted by using Origin 8.0 software to study the functional relation of CT value and Ci. The actual range of proton was equivalent to a range of water and incident proton energy could be calculated. Results There was a constant range of Ci of proton beam (70-250 MeV) between a variety of radiation equivalent material and water. There was a functional relation between CT value and Ci ( r = 0.999). The actual range of proton in radiation equivalent material can be equivalent to a range of the water. Conclusions CT values and a range of proportional coefficient ( Ci ),and the actual required range of the tumor could be used to accurately calculate the water equivalent range,and the incident proton energy to the position of Bragg peak. A new exploration for using CT technology in proton treatment planning system could be obtained.