CAJ | 학술논문

为阐述分野照射治疗方式应用于中国科学院近代物理研究所(IMP)肿瘤重离子临床治疗试验研究的理论基础，利用Monte Carlo (MC)软件包Gate/Geant4模拟计算了碳离子束分野照射分野衔接处的横向剂量分布，得到了患者摆位误差±1.0 mm范围内的横向剂量分布和分野衔接处中心剂量随分野间距的变化关系，计算了分野间距5.0 mm的横向剂量分布。将分野间距5.0 mm的分野照射与整野照射的MC结果进行比较，发现：在靶区范围内两者模拟的剂量偏差在6.8%以内，符合程度较好，并提出了在患者定位精确度较高的情况下(即患者治疗体位摆位误差在±1.0 mm范围)解决分野衔接处剂量热点问题的可行方法，从而较大幅度地提高了分野照射时靶区范围内的剂量均匀性。
위천술분야조사치료방식응용우중국과학원근대물리연구소(IMP)종류중리자림상치료시험연구적이론기출，이용Monte Carlo (MC)연건포Gate/Geant4모의계산료탄리자속분야조사분야함접처적횡향제량분포，득도료환자파위오차±1.0 mm범위내적횡향제량분포화분야함접처중심제량수분야간거적변화관계，계산료분야간거5.0 mm적횡향제량분포。장분야간거5.0 mm적분야조사여정야조사적MC결과진행비교，발현：재파구범위내량자모의적제량편차재6.8%이내，부합정도교호，병제출료재환자정위정학도교고적정황하(즉환자치료체위파위오차재±1.0 mm범위)해결분야함접처제량열점문제적가행방법，종이교대폭도지제고료분야조사시파구범위내적제량균균성。
To characterize the theoretical basis of field patching technique in carbon ion beam therapy, Monte Carlo software package Gate/Geant4 was used to simulate the lateral dose distribution of matched fields. The lateral dose distribution of the matched fields within ±1.0 millimeter of patient positioning error and the rela-tionship between the central dose of the matched fields and the field patching gap were obtained. Moreover, the lateral dose profile of field patching irradiation with 5.0 mm gap was simulated. While comparing the lateral dose distribution of field patching irradiation with 5.0 mm gap with the undivided field irradiation, a good agreement between both results with a maximum dose deviation of 6.8% was observed within the target volume. Hence a feasible method for solving the issue of dose hotspots during field patching under the condition of higher patient positioning accuracies (patient positioning error within ±1.0 millimeter) was proposed and the dose homogeneity within the target volume could be greatly improved when field patching technique is adopted in carbon ion beam therapy.