CAJ | 학술논문

目的比较旋转调强技术与常规固定野调强技术在鼻咽癌计划中对靶区及危及器官剂量学差异.方法选取10例同步加量放疗鼻咽癌患者,通过瓦里安Eclipse 8.6计划系统分别制定旋转调强放疗(IMAT)计划和固定野调强放疗(IMRT)计划,运用剂量体积直方图评价两种计划的靶区(PTV、PTV1、PTV2)及危及器官剂量参数、机器跳数(MU)和治疗时间(T).结果 IMAT和IMRT计划的PTV、PTV1、PTV2适形指数均不同,分别为0.71和0.75(Z=-2.32,P＜0.05)、0.54和0.59(Z=-2.56,P＜0.05)、0.71和0.78(Z=-2.52,P＜0.05);均匀指数均相似,分别为10.5和11.2(Z=-0.84,P＞0.05)、13.1和17.1(Z=-1.68,P＞0.05)、14.1和13.3(Z=-1.01,P＞0.05).IMAT和IMRT计划的脑干平均剂量相似,分别为(3512.8±406.2)cGy和(3384.3±361.3)cGy(Z=-1.82,P＞0.05),最大剂量也相似,分别为(5528.1±192.9)cGy和(5727.5±356.3)cGy(Z=-1.12,P＞0.05);脊髓最大剂量不同,分别为(4186.1±8 8.7)cGy和(4390.2±74.9)cGy(Z=-2.38,P＜0.05).两种计划中双侧腮腺平均剂量、腮腺33%体积受照剂量(D33)、D50、D60均相似(P值均＞0.05),正常组织[定义为全身(body)减去PTV,即B-P]受照500 cGy体积占总B-P体积百分比(V5)、V10均也相似(P值均＞0.05),但V15、V20、V25、V30、V35、V40、V45、V50均不同(P值均＜0.05).两种计划的MU不同,MUIMRT=1308±213,MUIMAT=606±96(Z=-2.52,P＜0.05).结论 IMAT计划靶区剂量覆盖与IMRT计划相当,适形度好于IMRT计划;危及器官受照剂量相当,B-P受照剂量明显降低;可减少机器跳数和治疗时间.
목적 비교선전조강기술여상규고정야조강기술재비인암계화중대파구급위급기관제량학차이.방법 선취10례동보가량방료비인암환자,통과와리안Eclipse 8.6계화계통분별제정선전조강방료(IMAT)계화화고정야조강방료(IMRT)계화,운용제량체적직방도평개량충계화적파구(PTV、PTV1、PTV2)급위급기관제량삼수、궤기도수(MU)화치료시간(T).결과 IMAT화IMRT계화적PTV、PTV1、PTV2괄형지수균불동,분별위0.71화0.75(Z=-2.32,P＜0.05)、0.54화0.59(Z=-2.56,P＜0.05)、0.71화0.78(Z=-2.52,P＜0.05);균균지수균상사,분별위10.5화11.2(Z=-0.84,P＞0.05)、13.1화17.1(Z=-1.68,P＞0.05)、14.1화13.3(Z=-1.01,P＞0.05).IMAT화IMRT계화적뇌간평균제량상사,분별위(3512.8±406.2)cGy화(3384.3±361.3)cGy(Z=-1.82,P＞0.05),최대제량야상사,분별위(5528.1±192.9)cGy화(5727.5±356.3)cGy(Z=-1.12,P＞0.05);척수최대제량불동,분별위(4186.1±8 8.7)cGy화(4390.2±74.9)cGy(Z=-2.38,P＜0.05).량충계화중쌍측시선평균제량、시선33%체적수조제량(D33)、D50、D60균상사(P치균＞0.05),정상조직[정의위전신(body)감거PTV,즉B-P]수조500 cGy체적점총B-P체적백분비(V5)、V10균야상사(P치균＞0.05),단V15、V20、V25、V30、V35、V40、V45、V50균불동(P치균＜0.05).량충계화적MU불동,MUIMRT=1308±213,MUIMAT=606±96(Z=-2.52,P＜0.05).결론 IMAT계화파구제량복개여IMRT계화상당,괄형도호우IMRT계화;위급기관수조제량상당,B-P수조제량명현강저;가감소궤기도수화치료시간.
Objective To compare the dosimetric differences of target volume and organ at risk between intensity-modulated arc therapy (IMAT) and simultaneously integrated boost intensity-modulated radiotherapy (SIB-IMRT) in nasopharyngeal carcinoma. Methods IMAT and SIB-IMRT treatment plans of 10 nasopharyngeal carcinoma cases were generated by Varian Eclipse ver8. 6 treatment planning system. The dosimetric parameters of target volume and organ at risk (OAR), the monitor units (MU) and treatment time were compared between IMAT and SIB-IMRT treatment plan. Results The conformal index ( CI ) of PTV, PTV1, PTV2 of IMAT and SIB-IMRT were 0. 71 and 0. 75 ( Z = - 2. 32, P ＜ 0. 05 ), 0. 54 and 0. 59 (Z= -2.56,P＜0.05), 0.71 and 0.78(Z= -2.52,P＜0.05), respectively. the homogenous index (HI) of PTV, PTV1, PTV2 of IMAT and SIB-IMRT were 10.5 and 11.2(Z= -0. 84,P＞0.05),13. 1 and 17. 1(Z= -1.68,P＞0.05) and 14. 1 and 13.3(Z= -1. 01,P＞0.05) respectively;the brain-stem mean does were 3512. 8 cGy ± 406. 2 cGy and 3384. 3 cGy ± 361.3 cGy ( Z= - 1.82, P ＞ 0. 05 ); the brain-stem maximum dose were 5528. 1cGy ± 192. 9 cGy and 5727. 5 cGy ± 356. 3 cGy ( Z = - 1.12, P ＞ 0. 05 ); the maximum dose of spinal-cord were were 4186. 1cGy ± 88.7 cGy and 4390. 2 cGy ± 74. 9 cGy ( Z =-2. 38 ,P ＜ 0. 05 ). There were no significant differences between parotid dose and normal tissue ( P ＞0. 05. ) MU were 606 ± 96 and 1308 ± 213 for IMAT and SIB-IMRT ( Z= - 2. 52, P ＜ 0. 05 ). Conclusions The IMAT plan showed a better conformal index than SIB-IMRT plan, with the same dosimetric parameters of the target volume and OAR. The IMAT plan could reduce normal tissues dose, monitor units and treatment time in the treatment of nasopharyngeal carcinoma.