摘要
目的:探讨Tomo HD分段式计划在实施女性全中枢照射(CSI)卵巢保护中的可行性及其剂量学特点。方法:选取8例已行全中枢照射的女性患者(其中生殖细胞瘤4例,髓母细胞瘤4例),照射靶区包括全脑全脊髓,采用pinnacle计划系统完成靶区及正常器官勾画(卵巢保护区域定义为VIP),处方剂量为36 Gy/20次,采用Tomo HD螺旋断层调强与断层径照调强接野技术,实现女性CSI患者卵巢保护的分段计划设计:上段计划(腰3水平以上)采用螺旋断层调强模式;下段计划(腰3水平以下)采用断层径照调强模式;应用HI.Art计划系统Summation模块将两段计划进行融合后,通过剂量体积直方图(DVH)统计分析靶区和各危及器官的剂量参数,并评估治疗计划的总出束时间。结果:分段式全中枢照射计划融合后统计Dmean、Dmax分别为(37.15±0.20)Gy和(41.22±0.41)Gy;D2、D98分别为(38.49±0.29)Gy和(35.27±0.46)Gy,V36为(95.70±1.16)%,实现了对靶区的较好覆盖。正常器官除眼球与心脏外,其他器官Dmean均<10 Gy,其中晶体Dmax为(5.10±1.19)Gy,卵巢保护区Dmax为(7.30±1.07)Gy;上、下段计划平均出束时间分别为(493.6±91.6)s和(289.24±63.45)s。结论:Tomo HD分段式计划在实现女性CSI靶区剂量无缝衔接的同时有效避开了对卵巢保护区域的照射,具有较高的临床应用价值。
Objective： To explore the feasibility and dosimetry characteristic of Tomo HD plans which were divided into two segments in protecting for ovary during implementing craniospinal irradiation（CSI） for female. Methods： 8 female patients received CSI（4 cases were germ-cell tumor, 4 cases were medulloblastoma）, and the target region of irradiation included whole brain and whole spinal marrow. The Pinnacle system was adopted to sketch the target region and normal organ（the protecting area of ovary was defined as VIP）, and the dosage of prescription was 36 Gy/20 F. The helical Tomo HD intensity modulation therapy and Tomo Director intensity modulation were adopted to achieve design of sectional plan for protecting ovary of female patients received CSI. The helical Tomo HD intensity modulation mode was used in upper segment plan（above third lumbar vertebra） and Tomo Director intensity modulation mode was used in lower segment plan（under third lumbar vertebra）. Summation mode of HI. Art planning system was used to combine the two segments planning, and the target region and dosage parameter of organ at risk（OAR） were statistically analyzed through using dose volume histogram（DVH）. Besides, the total beam-on time of curative plan was evaluated. Results： After the combination of the two segments planning, Dmean and Dmax were（37.15±0.20）Gy and（41.22±0.41）Gy, respectively. D2 and D98 were（38.49±0.29）Gy and（35.27±0.46）Gy, respectively. V36 was（95.70±1.16）%, and the cover of target region was appreciated. All of the Dmean of other organs were 10 Gy except for eyeball and heart in normal organs, and the Dmax of crystalline lens was（5.10±1.19）Gy, while the Dmax of protected area for ovary was（7.30±1.07）Gy. The average beam-on time of upper segment and lower segment were（493.6±91.6）s and（289.24±63.45）s, respectively. Conclusion： The Tomo HD plan which combined of two segments effectively protects the ovary of female received CSI when it achieve the seamless connection for dosage of target region. It has higher application value in clinical practices.
出处
《中国医学装备》
2017年第7期5-8,共4页
China Medical Equipment
基金
国家重点研发计划(2016YFC0904600)"以生物组学特征与多模态功能影像为基础的多线束精准放疗方案研究"
解放军总医院临床科研扶持基金(2017FC-WJFWZX-04)"基于旋转调强全中枢照射的临床研究"
