【摘要】 背景与目的:调强放射治疗已经被广泛运用于盆腔肿瘤的治疗,由于适形及剂量均匀的高度性,使得靶体积能够较传统"四盒野"获得缩小,降低了膀胱和小肠正常器官剂量-体积的相关毒性。但较小的靶体积另一方面又难以补偿器官移动所造成靶区边缘欠量的风险。本文旨在探讨膀胱不同充盈时态、自然状态及人工干预憋尿对宫体、宫颈变形位移变化的影响,以期对妇科肿瘤放疗计划的制定提供参考。方法:24例宫颈癌患者,通过人工干预使膀胱处于空虚、半充盈及充盈时态下,连续进行3次CT扫描。比较空虚-充盈、空虚-半充盈、半充盈-充盈三组膀胱体积充盈变化间,宫颈、宫体位移的变化。24例患者中选取13例患者进行自然憋尿膀胱充盈,11例患者进行人工干预膀胱充盈的治疗CT扫描,两组分别与当日的计划CT充盈时相的宫颈位移进行比较。结果:宫颈在空虚-充盈组中,在前、上、下方向平均位移最大,为0.7～1.0 cm;在空虚-半充盈组中,6个方位平均最大位移≤0.6 cm;在半充盈-充盈组中,6个方位平均最大位移≤0.8 cm。宫体在空虚-充盈组中,在前、上、下方向平均位移最大,为0.8～0.9 cm;在空虚-半充盈组中,6个方位上平均最大位移≤0.5 cm;在半充盈-充盈组中,6个方位平均最大位移≤0.6 cm。宫颈肿物直径与宫颈在前、左、右、上4个方向上位移变化有明显回归线性相关关系(P=0.000)。人工干预充盈的治疗CT与计划CT扫描在6个方向上的宫颈位移变化差异无统计学意义(P=0.150);自然憋尿充盈的治疗CT与计划CT扫描在6个方向上的宫颈位移变化差异也无统计学意义(P=0.265)。结论:膀胱充盈体积变化会对宫体、宫颈的位置产生影响,并且随着充盈体积变化的增加,平均最大位移改变越明显。同时自然憋尿充盈的差异并不会导致宫颈有意义的位移改变。更多还原

【Abstract】 Background and purpose:Intensity-modulated radiotherapy(IMRT) has been widely used in the treatment of pelvic tumors,due to the height on the conformal and dose uniformity.Dose-volume related toxicity on normal tissue such as bladder and small intestine can be reduced compared with conventional "four box field" technique.But the smaller target volume is difficult to compensate the underdose risk at the edge of target volume caused by organs motion.This study aimed to investigate deformation changes of uterus body-cervix under bladder filling variation and comparison holding back urine between natural and manual intervention.And aimed to provide a reference for the formulation of radiotherapy planning in gynecologic oncology.Methods:The first part of the study: 24 cervical patients consecutive underwent CT scans 3 times through manual intervention to make bladder in empty,half full and full respectively.Deformation changes of uterus body-cervix among 3 groups bladder volume variation of empty-full,empty-half full,half full-full were compared.The second part of the study: 13 patients by random were selected from total 24 patients for bladder filling by natural intervention,11 patients for bladder filling underwent CT scans by manual intervention,then the deformation changes of cervix between the 2 groups of treatment CT and planning CT were compared.Results:The mean maximal displacement of cervix for empty-full group in anterior and superior directions was 1.0 cm.The mean maximal displacement in empty-half full group was less than 0.6 cm.The mean maximal displacement in half full-full group was less than 0.8cm.The mean maximum displacement of uterus body for empty-full group in anterior,superior and inferior directions was maximum: 0.8-0.9 cm.The mean maximal displacement in empty-half full group was less than 0.5 cm.The mean maximal displacements in half full-full group was less than 0.6 cm.There was linear regression relationship between cervical tumor diameters and 4 directions of anterior,left,right,superior(P=0.000).Deformation changes of cervix had no statistically significant between treatment CT and planning CT by manual intervention in 6 directions(P=0.265).Conclusion:Volume variation of bladder filling can impact deformation changes of uterus body-cervix.With the increase filling volume changes,the mean maximum displacement change become more obvious.At the same time,the difference of natural holding back urine will not influent cervical meaningful displacement changes.更多还原