Computed radiography(CR)imaging has high irradiation tolerance and it is easy to archive CR images along with other image information by Digital Imaging and Communications in Medicine(DICOM)format,and to process them....Computed radiography(CR)imaging has high irradiation tolerance and it is easy to archive CR images along with other image information by Digital Imaging and Communications in Medicine(DICOM)format,and to process them.CR can be used in radiation Quality Control(QC)task and verification of treatment setting-up.In this paper,the role of high-energy CR in radiation oncology is studied.The patients were imaged by CR system and EPID before radiotherapy.All verification images were acquired with 1–2 MU(Monitor Unit)using 6 MV X-rays.QC for a linac was done with film and high-energy CR to collect the data on daily,weekly and monthly basis.The QC included Multileaf Collimators(MLC)calibration and mechanical iso-centre check.CR was also adapted to verify patient position,the film was used to compare with digitally reconstructed radiographs(DRR)and portal image from EPID. Treatment setting-up was verified based on the result of comparison.High quality verification images could be acquired by the CR system.Comparing to EPID,the results showed that the system was suitable for practical use to acquire daily verification images,and it was useful to fulfill part of quality assurance(QA)in radiation oncology.The quality of image acquired by the high-energy CR system is comparable or even better than DRRs and portal images. The final treatment set-up for the patients could be verified more accurately with the CR system.展开更多
目的总结SOLO CR系统高效、可靠、稳定运行,获取高质量的数字图象质量控制方法。方法结合实际情况对AGFA ADC SOLO CR制定详细的质量控制计划,适时监控,实施有效的保养与维修,使系统保持在正常运转状态。结果保证了CR系统工作正常、稳...目的总结SOLO CR系统高效、可靠、稳定运行,获取高质量的数字图象质量控制方法。方法结合实际情况对AGFA ADC SOLO CR制定详细的质量控制计划,适时监控,实施有效的保养与维修,使系统保持在正常运转状态。结果保证了CR系统工作正常、稳定的运行,获得了比较好的预期效果。结论得当的、行之有效的质量控制是非常必要的,为输出高质量的数字图像提供了可靠的保障。展开更多
目的对肺癌和食管癌患者在放疗过程中行基于电子射野影像装置(EPID)的在体剂量验证,探讨影响在体剂量验证结果准确性的因素,并推荐应用在体剂量验证的流程及规范。方法单纯随机抽样法选取2022年5月至2022年8月在金华市中心医院放疗科行...目的对肺癌和食管癌患者在放疗过程中行基于电子射野影像装置(EPID)的在体剂量验证,探讨影响在体剂量验证结果准确性的因素,并推荐应用在体剂量验证的流程及规范。方法单纯随机抽样法选取2022年5月至2022年8月在金华市中心医院放疗科行食管癌和肺癌放疗的患者32例(其中,肺癌14例,食管癌18例),在uRT-TPOIS计划系统上制作动态调强放疗(dIMRT)及EPID在体剂量验证(In vivo EPID)计划,使用uRT-linac 506c直线加速器进行治疗。治疗过程中行在体剂量验证,其中,肺癌病例行In vivo EPID的分次共238次,执行图像引导放疗(IGRT)共80次,食管癌病例行In vivo EPID的分次共414次,执行IGRT共105次。设置阈值并获取每个射野的2Dγ通过率,分析低于阈值的分次射野,并结合在线CT影像及三维重建剂量结果,进一步分析影响γ通过率下降的主要因素。结果肺癌、食管癌3 mm/5%γ通过率均值分别为95.1%±5.7%、96.5%±4.5%;3 mm/3%γ通过率均值为91.5%±8.4%、92.2%±4.9%;2 mm/2%γ通过率均值分别为:79.1%±14.1%、83.7.2%±8.2%,病种之间通过率差异无统计学意义(P>0.05)。靠近0°/180°射野组(A组)的γ通过率高于靠近90°/270°射野组(B组)(3 mm/5%,Z=-25.4,P<0.05;3 mm/3%,Z=-26.8,P<0.05)。通过IGRT纠正摆位误差,可显著提高γ通过率(IGRT和非IGRT下,3 mm/5%γ通过率均值为96.3%±5.1%、96.0%±4.9%,Z=-5.50,P<0.05;3 mm/3%γ通过率均值92.3%±8.0%、91.3%±7.7%,Z=-9.54,P<0.05)。肿瘤及正常组织体积变化和运动变化、定位和治疗前准备充分与否等都会影响在体剂量验证的结果。结论放疗过程中进行EPID在体剂量验证能避免错误照射,但需规范EPID在体剂量验证流程,以避免人为因素等导致的通过率降低。展开更多
基金Supported by the Municipal Health Bureau of Shanghai(Contract No.04017)
文摘Computed radiography(CR)imaging has high irradiation tolerance and it is easy to archive CR images along with other image information by Digital Imaging and Communications in Medicine(DICOM)format,and to process them.CR can be used in radiation Quality Control(QC)task and verification of treatment setting-up.In this paper,the role of high-energy CR in radiation oncology is studied.The patients were imaged by CR system and EPID before radiotherapy.All verification images were acquired with 1–2 MU(Monitor Unit)using 6 MV X-rays.QC for a linac was done with film and high-energy CR to collect the data on daily,weekly and monthly basis.The QC included Multileaf Collimators(MLC)calibration and mechanical iso-centre check.CR was also adapted to verify patient position,the film was used to compare with digitally reconstructed radiographs(DRR)and portal image from EPID. Treatment setting-up was verified based on the result of comparison.High quality verification images could be acquired by the CR system.Comparing to EPID,the results showed that the system was suitable for practical use to acquire daily verification images,and it was useful to fulfill part of quality assurance(QA)in radiation oncology.The quality of image acquired by the high-energy CR system is comparable or even better than DRRs and portal images. The final treatment set-up for the patients could be verified more accurately with the CR system.
文摘目的总结SOLO CR系统高效、可靠、稳定运行,获取高质量的数字图象质量控制方法。方法结合实际情况对AGFA ADC SOLO CR制定详细的质量控制计划,适时监控,实施有效的保养与维修,使系统保持在正常运转状态。结果保证了CR系统工作正常、稳定的运行,获得了比较好的预期效果。结论得当的、行之有效的质量控制是非常必要的,为输出高质量的数字图像提供了可靠的保障。
文摘目的对肺癌和食管癌患者在放疗过程中行基于电子射野影像装置(EPID)的在体剂量验证,探讨影响在体剂量验证结果准确性的因素,并推荐应用在体剂量验证的流程及规范。方法单纯随机抽样法选取2022年5月至2022年8月在金华市中心医院放疗科行食管癌和肺癌放疗的患者32例(其中,肺癌14例,食管癌18例),在uRT-TPOIS计划系统上制作动态调强放疗(dIMRT)及EPID在体剂量验证(In vivo EPID)计划,使用uRT-linac 506c直线加速器进行治疗。治疗过程中行在体剂量验证,其中,肺癌病例行In vivo EPID的分次共238次,执行图像引导放疗(IGRT)共80次,食管癌病例行In vivo EPID的分次共414次,执行IGRT共105次。设置阈值并获取每个射野的2Dγ通过率,分析低于阈值的分次射野,并结合在线CT影像及三维重建剂量结果,进一步分析影响γ通过率下降的主要因素。结果肺癌、食管癌3 mm/5%γ通过率均值分别为95.1%±5.7%、96.5%±4.5%;3 mm/3%γ通过率均值为91.5%±8.4%、92.2%±4.9%;2 mm/2%γ通过率均值分别为:79.1%±14.1%、83.7.2%±8.2%,病种之间通过率差异无统计学意义(P>0.05)。靠近0°/180°射野组(A组)的γ通过率高于靠近90°/270°射野组(B组)(3 mm/5%,Z=-25.4,P<0.05;3 mm/3%,Z=-26.8,P<0.05)。通过IGRT纠正摆位误差,可显著提高γ通过率(IGRT和非IGRT下,3 mm/5%γ通过率均值为96.3%±5.1%、96.0%±4.9%,Z=-5.50,P<0.05;3 mm/3%γ通过率均值92.3%±8.0%、91.3%±7.7%,Z=-9.54,P<0.05)。肿瘤及正常组织体积变化和运动变化、定位和治疗前准备充分与否等都会影响在体剂量验证的结果。结论放疗过程中进行EPID在体剂量验证能避免错误照射,但需规范EPID在体剂量验证流程,以避免人为因素等导致的通过率降低。