CAJ | 학술논문

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 cm3,体积比值为1.10±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.
목적 통과대폐부종류진행호흡문공PET/CT연구,급여폐부종류방료파구구화지도,최종사환자접수합리적조사파구.방법 대20개악성결절진행호흡문공PET/CT여상규PET/CT채집,비교폐부불동위치결절적평균사유PET체적여삼유PET체적적차별,이급평균사유CT체적여삼유CT체적적차별.이평균사유체적여삼유체적적상대차치작위체적간적차이,분별종결절위치、운동폭도연구기대사유체적여삼유체적적영향.결과 용량충방법측득적평균사유PET체적비삼유PET체적대17.2％.체적상대차치여결절호흡운동폭도급결절위치유관.하폐화폐문병조평균사유PET체적여삼유PET체적적평균차치위26.5％,원원대우상폐화흉막병조적평균차치(2.7％).당결절호흡운동폭도대우3 mm시,사유여삼유PET체적차치적평균치위24.3％;소우3 mm시,평균치위1.8％.평균사유CT체적비삼유CT체적대3.9％,체적차치범위위0.2～5.9 cm3,체적비치위1.10±0.32.지유재하폐,평균사유CT체적명현대우삼유CT체적,평균차치위11.3％.결론 대우고근간비적하폐결절,용평균사유PET구화종류파구경정학사;대우폐문주위적결절,고필평균사유PET체적작위종류파구;대우상폐화흉막적결절,건의채용저제량호흡문공소묘차이경고필료호흡운동적평균사유CT체적구화파구.
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±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 lung nodules close to the liver and spleen,the volume defined by average four-dimensional PET showed more accuracy for sketching tumor target.For nodules around the hilus of the lung,the volume defined by average four-dimensional PET can be considered as tumor target.For the upper lobe and pleural nodules,the volume defined by average four-dimensional CT was selected for the target outline,which adopted low-dose RG scan and considered breathing movement.