宫颈癌VMAT放疗计划中实际射野角度与射野角度归零的剂量验证比较  

Comparison of Dose Verification between Actual Field Angle and Zero Field Angle of VMAT Plan for Cervical Cancer

作　　者：顾宵寰 李金凯 李彩虹 王沛沛 昌志刚 胡晓伟 李华玲 季茹 武娟 GU Xiao-huan;LI Jin-kai;LI Cai-hong;WANG Pei-pei;CHANG Zhi-gang;HU Xiao-wei;LI Hua-ling;JI ru;WU Juan(Department of radiation Oncology,Jiangsu Province Hospital(the First Affiliated Hospital with Nanjing Medical University),Nanjing 210000,Jiangsu Province,China)

机构地区：[1]江苏省人民医院(南京医科大学第一附属医院)放射治疗科,江苏南京210000

出　　处：《中国CT和MRI杂志》2025年第2期140-143,共4页Chinese Journal of CT and MRI

基　　金：国家自然科学基金(82003228)。

摘　　要：目的以宫颈癌为例,比较分析容积旋转调强放疗(volumetric modulated arc therapy,VMAT)计划验证中,实际射野角度和射野角度归零的γ通过率的差异性,为临床提供参考。方法选取20例宫颈癌患者的VMAT计划进行计划验证,探测矩阵使用PTW OCTAVIUS 1500,模体使用PTW OCTAVIUS 4D,分析软件使用PTW VeriSoft,在医科达AXESSE电子直线加速器上,分别进行实际射野角度和射野角度归零的计划验证测量,选用2mm/2%和3mm/3%两种标准进行γ通过率分析。并进一步将机架角度分解为水平线上和水平线下两种角度范围,探究治疗床对γ通过率的影响。比较几种验证结果的差异性。结果20例患者γ通过率(%),实际射野角度(2mm/2%91.9±2.6,3mm/3%99.1±0.4)相比射野角度归零(2mm/2%94.0±2.3,3mm/3%99.5±0.3)有所降低(P<0.05)且差异较大(Cohen'sd值,2mm2%1.212,3mm3%0.884);水平线上角度范围,实际射野角度(2mm/2%93.0%,3mm/3%99.3%)相比射野角度归零(2mm/2%93.9%,3mm/3%99.5%)有所降低(P<0.05)且差异中等(Cohen's d值,2mm2%0.562,3mm3%0.568);水平线下角度范围,实际射野角度(2mm/2%90.8%,3mm/3%99.1%)相比射野角度归零(2mm/2%93.9%,3mm/3%99.6%)有所降低(P<0.05)且差异很大(Cohen's d值,2mm2%2.472,3mm3%1.464)。结论相比于射野角度归零,实际射野角度计划验证考虑到了实际治疗时机架旋转的问题,例如在不同角度,加速器机架和多叶准直器在重力作用下的影响、治疗床的影响等因素,更能反映实际治疗情况。Objective Taking cervical cancer as an example,the difference in theγpass rate of the actual field Angle and the field Angle in the planned validation of volume rotating intensity modulated radiotherapy(Volumetric Modulated Arc Therapy,VMAT)is provided for clinical reference.Methods VMAT plans of 20 cervical cancer patients were selected for plan validation,PTW OCTAVIUS 1500 for detection matrix,PTW OCTAVIUS 4D for mold,PTW VeriSoft for AXESSE On the accelerator,the planned verification measurement of actual field Angle and field Angle were respectively,and two standards of 2mm/2%and 3mm/3%were selected forγpass rate analysis.Further,the frame angle was decomposed into the upper and lower horizontal angles to explore the influence of the treatment bed on theγpass rate.Comparing the variability of several validation results.Resultsγpass rate(%)in 20 patients,actual field angle(2mm/2%91.9±2.6,3mm/3%99.1±0.4)compared to field angle(2mm/2%94.0±2.3,3mm/3%99.5±0.3)decreased(P<0.05)and varied significantly(Cohen's d value,2mm2%1.212,3mm3%0.884);actual angular range(2mm/2%93.0%,3mm/3%99.3%)decreased with zero(2mm/2%93.9%,3mm/3%99.5%)(P<0.05)and moderate difference(Cohen'sd,2mm2%0.562,3mm 3%0.568);below the horizontal angle range,the actual field angle(2mm/2%90.8%,3mm/3%99.1%)was decreased(2mm/2%93.9%,3mm.3%99.6%)(Cohen's d value,2mm2%2.472,3mm3%1.464).Conclusion Compared with the field angle zero,the actual field angle plan verification takes into account the problem of the actual treatment timing frame rotation,such as the accelerator frame and multi-leaf collimor at different angles Impact,the influence of the treatment bed and other factors,more can reflect the actual treatment situation.

关 键 词：OCTAVIUS 4D VMAT 计划验证 γ通过率 射野角度 剂量验证 

分 类 号：R815.6[医药卫生—放射医学]