呼吸门控PET/CT对于肺癌放疗靶区勾画的指导  

Guiding the target delineation in radiation therapy of lung cancer by respiratory gated PET/CT

作　　者：张艳兰[1] 孙琦婷 武萍[2] 郝新忠[2] 秦志星[2] 程鹏亮[2] 武志芳[2] 李思进[2] 

机构地区：[1]山西医科大学第一医院放疗科,太原030001 [2]山西医科大学第一医院核医学科,太原030001 [3]山西省心血管病医院影像科,太原030001

出　　处：《国际放射医学核医学杂志》2015年第2期105-109,共5页International Journal of Radiation Medicine and Nuclear Medicine

基　　金：山西省科技攻关项目（20120321028-03）

摘　　要：目的 通过对肺部肿瘤进行呼吸门控PET/CT研究,给予肺部肿瘤放疗靶区勾画指导,最终使患者接受合理的照射靶区.方法 对20个恶性结节进行呼吸门控PET/CT与常规PET/CT采集,比较肺部不同位置结节的平均四维PET体积与三维PET体积的差别,以及平均四维CT体积与三维CT体积的差别.以平均四维体积与三维体积的相对差值作为体积间的差异,分别从结节位置、运动幅度研究其对四维体积与三维体积的影响.结果 用两种方法测得的平均四维PET体积比三维PET体积大17.2％.体积相对差值与结节呼吸运动幅度及结节位置有关.下肺和肺门病灶平均四维PET体积与三维PET体积的平均差值为26.5％,远远大于上肺和胸膜病灶的平均差值（2.7％）.当结节呼吸运动幅度大于3 mm时,四维与三维PET体积差值的平均值为24.3％;小于3 mm时,平均值为1.8％.平均四维CT体积比三维CT体积大3.9％,体积差值范围为0.2～5.9 cm^3,体积比值为1.10＆#177;0.32.只有在下肺,平均四维CT体积明显大于三维CT体积,平均差值为11.3％.结论 对于靠近肝脾的下肺结节,用平均四维PET勾画肿瘤靶区更精确些;对于肺门周围的结节,考虑平均四维PET体积作为肿瘤靶区;对于上肺和胸膜的结节,建议采用低剂量呼吸门控扫描且已经考虑了呼吸运动的平均四维CT体积勾画靶区.Objective To give target outline guidance for lung tumor radiation therapy by respiratory gating （RG） four-dimensional PET/CT for lung cancer.Eventually reasonable radiation target regions in treatment planning are received by patients.Methods Twenty malignant nodules were studied by RG PET/CT and conventional PET/CT.The differences of gross tumor volume defined by average four-dimensional PET and three-dimensional PET were compared in different lung locations.Differences of gross tumor volume defined by average four-dimensional CT and three-dimensional CT were also investigated.Differences between volume defined by average four-dimensional volumes and three-dimensional volumes were defined as relative difference of gross tumor volume,and influences for volume defined by four-dimensional PET and CT and three-dimensional PET and CT based on the nodal position and respiratory motion amplitude were also investigated in this study.Results Both volumes defined by average four-dimensional PET measured with two techniques were 17.2% greater than the volume defined by three-dimensional PET on average.The relative difference of the volume defined by average four-dimensional PET and three-dimensional PET was related to the nodal position and respiratory motion amplitude.The mean difference was 26.5% for the lower lobe and hilus of the lung,which was much greater than that of the upper lobe and pleura （2.7%）.When the respiratory motion amplitude of nodules was 〉3 mm,the difference between the volumes defined by average four-dimensional PET and three-dimensional PET was 24.3% （as 〈3 mm,difference was 1.8%）.The volume defined by average four-dimensional CT was 3.9% larger than the volume defined by three-dimensional CT,with difference range of nodule volume at 0.2 cm3 to 5.9 cm3 and ratios of 1.10＆#177;0.32.Only the nodules in the lower lobe showed significantly larger volumes defined by average four-dimensional CT than those defined by three-dimensional CT with average difference of 11.3%.Conclusions For lu

关 键 词：肺肿瘤 正电子发射断层显像术 体层摄影术 X线计算机 放疗靶区 体积比较 

分 类 号：R734.2[医药卫生—肿瘤] R730.44[医药卫生—临床医学]