摘要
目的探讨呼吸门控技术在早期周围型非小细胞肺癌(non-small cell lung cancer,NSCLC)立体定向放射治疗(stereotactic body radiation therapy,SBRT)方面的剂量学优势。方法回顾分析2016年11月~2019年3月应用呼吸门控技术实现SBRT治疗的10例早期NSCLC患者资料。10例患者应用4DCT方式定位,利用患者呼吸波形重建10组CT图像,把10组CT传输到MIM6.9.4工作站。应用MIM工作站的呼吸运动分析功能产生全时相最大密度投影(MIP-10)、全时相平均密度投影(Mean-10)、呼吸末3时相最大密度投影(MIP-10)、呼吸末3时相平均密度投影(Mean-10),靶区勾画用MIP图像,计划设计用Mean图像。放疗医师在MIM工作站上勾画IGTV-10、IGTV-3,并外放生成CTV-10、CTV-3、PTV-10、PTV-3,比较靶区体积差异。靶区勾画完毕后将图像从MIM传输至瓦里安工作站,设计全时相计划(Plan-10)和呼气末3个连续时相呼吸门控计划(Plan-3)。比较患侧肺的V2.5、V5、V20、V25、患侧肺平均照射剂量D_(mean)、健侧肺D_(mean)、全肺D_(mean),并比较脊髓D_(max)、心脏D_(max)、食道D_(max)、气管D_(max)、胸壁D_(max)。结果呼吸门控技术减小了IGTV、CTV、PTV的靶区体积(P<0.05)。门控计划相比4DCT全时相计划降低了患侧肺V2.5、V5、V20、V25,降低了患侧肺D_(mean)、健侧肺D_(mean)、全肺D_(mean)(P<0.05),同时也降低了脊髓D_(max)、心脏D_(max)、食道D_(max)、气管D_(max)、胸壁D_(max),脊髓D_(max)差异无统计学意义(P>0.05),其余差异均有统计学意义(P<0.05)。结论对于早期周围型NSCLC患者,应用呼气末3个连续时相来实现靶区勾画和计划设计,相比于全时相既缩小了靶区体积又降低了危及器官的照射剂量,具有一定剂量学优势。
Objective To study the dosimetric advantages of respiratory gating technique in stereotactic body radiation therapy(SBRT)for early non-small cell lung cancer(NSCLC).Methods To retrospectively analyze the data of 10 patients with early NSCLC who applied respiratory gating technology to achieve SBRT treatment from November 2016 to March 2019.Ten patients were located by the 4 DCT method,and 10 sets of CT images were reconstructed using the patient’s breathing waveform,and the 10 sets of CT were transmitted to the MIM6.9.4 workstation.Respiratory motion analysis function of the MIM workstation was used to generate the full-time phase maximum intensity projection(MIP-10),the full-time phase average intensity projection(Mean-10),3 phase maximum intensity projection(MIP-3)at the end-expiratory breath and 3 phase average intensity projection(Mean-3)at the end-expiratory breath,MIP image for target area delineation,and Mean image for plan design.The IGTV-10 and IGTV-3 were sketched on the MIM workstation by radiotherapy physicians,and CTV-10,CTV-3,PTV-10,PTV-3 were generated,and the volume differences of target areas were compared.After the target sketch,the image was transferred from the MIM to the Varian workstation,full-time phase plan(Plan-10)and three consecutive end-expiratory phase respiration gating plan(Plan-3)were designed by medical physicist.The V2.5,V5,V20,V25 of affected lung,affected lung D_(mean),normal lung D_(mean),whole lung D_(mean)were compared,and spinal cord D_(max),heart D_(max),esophagus D_(max),trachea D_(max),chest wall D_(max)were also compared.Results The respiratory gating technique reduced the target area volume of IGTV,CTV and PTV(P<0.05).The Plan-3 than Plan-10 reduced affected lung V2.5,V5,V20,V25 exposure volume,reduced affected lung D_(mean),the normal lung D_(mean),the whole lung D_(mean)(P<0.05),at the same time also reduced the spinal cord D_(max),heart D_(max),esophagus D_(max),trachea D_(max),chest wall D_(max),there was no statistical difference for spinal cord D_(max)(P>0.05),the rest difference had statistical significance(P<0.05).Conclusion For patients with early peripheral NSCLC,the application of three continuous end-expiratory phase to achieve target sketch and planning design,not only reduces the volume of the target area but also reduces the irradiation dose of the organs at risk,which has certain dosimetric advantages compared with the full-time phase.
作者
徐丽丽
徐广庆
徐丙臣
陈子印
XU Li-li;XU Guang-qing;XU Bing-chen;CHEN Zi-yin(Department of Radiation Therapy,The First Affiliated Hospital of Harbin Medical University,Harbin 150001,China;Office of Medical Responsibility Management,The First Affiliated Hospital of Harbin Medical University,Harbin 150001,China;Department of Radiation Therapy,Jilin Central General Hospital,Jilin 132011,China)
出处
《哈尔滨医科大学学报》
CAS
2021年第1期83-86,89,共5页
Journal of Harbin Medical University
作者简介
徐丽丽(1984-),女,放疗技师;通讯作者:陈子印,E-mail:chenziyin1020@126.com。
