CAJ | 학술논문

目的：探讨旋转容积调强技术（ VMAT）和固定野动态调强放疗技术（ DMLCI-MRT ）在宫颈癌根治性放疗中的剂量学差异及其保护骨盆骨髓的价值。方法选取9例接受根治性放疗的宫颈癌患者，在Eclipse 10.0计划系统上分别对其进行二弧VMAT计划和九野DMLC-IMRT计划设计，比较两者靶区、骨盆骨髓和其他危及器官的剂量学差异、加速器跳数和照射时间。结果与DMLC-IMRT计划相比，VMAT计划靶区适形性指数CI略好；两种计划的靶区均匀性指数HI和骨盆骨髓（V10，V20，V40）无差异，均能很好地满足临床要求；在 VMAT计划中，小肠 V40，V45和膀胱V45均略低于 DMLC-IMRT（P＜0.05），在直肠 V45的保护上 DMLC-IMRT 略优于 VMAT（P＜0.05），而直肠 Dmean 两者相似。 VMAT 计划的 MU 为848.4±58.8，较DMLC-IMRT 计划的1850.3±227.8明显减少（P＝0.000），VMAT的治疗时间为（136.2±3.6）s，仅为DMLC-IMRT的1/3（P＝0.000）。结论 VMAT计划可以达到或优于DMLC-IMRT DIMRT计划的靶区剂量分布，两者均能很好地降低骨盆骨髓受照剂量，保护其他盆腔脏器，同时明显减少加速器跳数和照射时间。
목적：탐토선전용적조강기술（ VMAT）화고정야동태조강방료기술（ DMLCI-MRT ）재궁경암근치성방료중적제량학차이급기보호골분골수적개치。방법선취9례접수근치성방료적궁경암환자，재Eclipse 10.0계화계통상분별대기진행이호VMAT계화화구야DMLC-IMRT계화설계，비교량자파구、골분골수화기타위급기관적제량학차이、가속기도수화조사시간。결과여DMLC-IMRT계화상비，VMAT계화파구괄형성지수CI략호；량충계화적파구균균성지수HI화골분골수（V10，V20，V40）무차이，균능흔호지만족림상요구；재 VMAT계화중，소장 V40，V45화방광V45균략저우 DMLC-IMRT（P＜0.05），재직장 V45적보호상 DMLC-IMRT 략우우 VMAT（P＜0.05），이직장 Dmean 량자상사。 VMAT 계화적 MU 위848.4±58.8，교DMLC-IMRT 계화적1850.3±227.8명현감소（P＝0.000），VMAT적치료시간위（136.2±3.6）s，부위DMLC-IMRT적1/3（P＝0.000）。결론 VMAT계화가이체도혹우우DMLC-IMRT DIMRT계화적파구제량분포，량자균능흔호지강저골분골수수조제량，보호기타분강장기，동시명현감소가속기도수화조사시간。
Objective To compare volumetic modulated radiotherapy ( VMAT) techniques with dynamic multileaf collimator intensi-ty-modulated radiotherapy ( DMLC-IMRT) techniques in cervical cancer treated with definitive whole pelvic radiotherapy , and to explore its advantage to protect the pelvic bone marrow ( PMB) .Methods CT datasets of 9 staged ⅡA~ⅢB intact cervical cancer patients were in-cluded.VMAT plans and DMLC-IMRT plans were created based on each CT dataset by planning treatment system (Eclipse 10.0).Plans were evaluated on parameters of target , PMB and other pelvic organs , derived from dose volume histograms .The MU and delivery time were scored to measure expected treatment efficiency .Results Both VMAT and DMLC-IMRT resulted in equivalent target coverage and heteroge-neity index (HI), but VMAT had a slightly improved conformity index (CI =0.93±0.00 for VMAT and 0.92±0.02 for DMLC-IMRT). Compared with DMLC-IMRT, VMAT showed comparable volume of PBM at dose level of 10, 20 and 40 Gy, and mildly reduced the volume of bowel at 40 Gy and 45 Gy dose level(P<0.05).Similar trends were observed for the bladder .However, on retumn the volume received 45 Gy were increased (P<0.05),and the mean doses were the similar .The MU from VMAT was (848.4±58.8)s corresponding to an average beam on time of(136.2±3.6)s per fraction of 2 Gy.IMRT plans presented significantly higher values with an average of MU =(1 850.3± 227.8)s and of beam on time =(353.2±25.1)s.Conclusions VMAT is invesgated for intact cervix cancer showing comparable avoidance of PBM and other organ at risk with umcompromised target coverage in regard to DMLC-IMRT.In combination with the confirmed shorter de-livery time and fewer MUs , could lead to clinically significant advances in the management of this highly aggressive cancer type .