联影直线加速器放疗在体剂量验证的应用研究  

Clinical application of radiotherapy based on UIH linear accelerators to in vivo dose verification

作　　者：谢家存 李良 梁恒坡 李亚琼 王志斌 Xie Jiacun;Li Liang;Liang Hengpo;Li Yaqiong;Wang Zhibin(Department of Cancer Center,Henan Provincial People′s Hospital,People′s Hospital of Zhengzhou University,People′s Hospital of Henan University,Zhengzhou 450003,China.)

机构地区：[1]河南省人民医院,郑州大学人民医院,河南大学人民医院肿瘤中心,郑州450003

出　　处：《中华放射医学与防护杂志》2023年第5期357-361,共5页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的研究基于联影直线加速器电子射野影像装置(EPID)在体剂量验证方法在临床中的应用。方法选取河南省人民医院收治的68例行容积旋转调强放疗(VMAT)的肿瘤患者,其中,头颈部32例、胸部16例和腹盆部20例。每位患者均执行治疗前Arccheck剂量验证(Pre Arccheck)、治疗前EPID剂量验证(Pre EPID),以及治疗中前3次和随后每周1次的扇形束计算机断层成像(FBCT)位置验证和在体EPID剂量验证(In vivo EPID)。当任一方向摆位误差(左右x、头脚y和垂直z)均<3 mm时实施治疗,并根据x、y和z计算三维摆位偏差d;否则,执行位置校正。结果 68例患者Pre EPID和In vivo EPID γ通过率分别为(99.97±0.1)%和(94.15±3.84)%,与Pre Arccheck的(98.86±1.48)%相比,差异有统计学意义(t=-6.12、9.43,P<0.05)。胸部、腹盆部和头颈部的In vivo EPID γ通过率相比,差异无统计学意义(P>0.05)。Pre EPID γ通过率和首次In vivo EPID γ通过率的差值(5.56±3.72)%与对应的三维摆位偏差d(1.46±1.51)mm之间无相关(P>0.05)。随着治疗进行,In vivo EPID γ通过率由第1周的(94.15±3.84)%逐步减小到第5周的(92.15±3.24)%;从第3周开始至第5周,In vivo EPID γ通过率与第1周的相比,差异均有统计学意义(t=2.48、2.75、3.09,P<0.05)。结论 3 mm内摆位误差不影响在体剂量验证的γ通过率,在体剂量验证γ通过率临床可接受阈值的确定仍需进一步的研究,同时在体剂量验证可为自适应放疗的临床应用提供一定的支持。Objective To explore the clinical application of the electronic portal imaging device(EPID)based on the linear accelerator produced by Shanghai United Imaging Healthcare Co.,Ltd.(UIH)to in vivo dose verification.Methods A total of 68 patients(32 cases with head and neck tumors,16 cases with chest tumors,and 20 cases with abdomen and pelvis tumors)who were treated with volumetric modulated arc therapy(VMAT)in the Henan Provincial People′s Hospital were selected in this study.Each patient underwent the pre-treatment dose verification using an Arccheck device(Pre Arccheck),the pre-treatment dose verification using an EPID(Pre EPID),and the in vivo dose verification using an EPID(In vivo EPID).Moreover,the position verification based on fan beam computed tomography(FBCT)was also performed for each patient in the first three treatments and then once a week.The patients were treated when the setup error in any direction(x:left-right,y:head-foot,z:vertical)was less than 3 mm;otherwise,position correction would be conducted.The three-dimensional setup deviation d was calculated according to setup errors x,y,and z.Results Theγpassing rates of dose verifications Pre EPID and In vivo EPID of 68 patients were(99.97±0.1)%and(94.15±3.84)%,respectively,significantly different from that(98.86±1.48)%of the Pre Arccheck dose verification(t=-6.12,9.43;P<0.05).Theγpassing rates of the chest,abdomen and pelvis,and head and neck in the In vivo EPID dose verification showed no significant differences(P>0.05).The difference in theγpassing rates(5.56±3.72)%between dose verifications Pre EPID and first In vivo EPID was unrelated to the three-dimensional setup deviation d(1.46±1.51 mm)(P>0.05).As the treatment proceeded,theγpassing rate of In vivo EPID gradually decreased from(94.15±3.84)%in the first week to(92.15±3.24)%in the fifth week.From the third week to the fifth week,theγpassing rates of In vivo EPID were significantly different from those in the first week(t=2.48,2.75,3.09,P<0.05).Conclusions The setup errors within

关 键 词：在体剂量验证 伽马通过率 电子射野影像装置 摆位误差 

分 类 号：R730.55[医药卫生—肿瘤]