320排动态容积CT对正常人肺实质不同区域灌注定量研究  

A Quantitatively Pilot Study of Pulmonary Perfusion of Healthy People by using 320-Detector Row Dynamic Volumetric CT

作　　者：方进[1] 毛家骥[2] 梁敏杰[1] 邓达标[1] 胡钰[1] 邹亚妮 李红林[1] 蔡湘怡 周全[1] 

机构地区：[1]暨南大学附属第一医院医学影像中心,广州510632 [2]中山大学孙逸仙纪念医院放射科,广州510120

出　　处：《临床放射学杂志》2016年第10期1593-1597,共5页Journal of Clinical Radiology

摘　　要：目的从定量角度初步探讨正常人肺实质肺循环及体循环的血流构成比情况,并比较正常不同区域灌注参数的差异,进一步探讨320排低剂量CT肺灌注技术的可行性和优越性。方法搜集胸片发现"可疑肺结节"、怀疑肿瘤肺转移或者食管癌患者需行胸部CT增强扫描者,最终将20例正常资料纳入研究。采用320排CT(Aquilion One,日本东芝医疗器械公司)进行肺容积扫描,扫描参数:电压80 k V,电流70 m A,采用自适应迭代剂量降低方法进行图像重建,后处理用最大斜率法数学模型,对容积数据用图像后处理软件进行分析,生成4条时间-密度曲线,并记录各个曲线达峰时间;分析得到肺实质伪彩色血流灌注图像,分别显示肺动脉血流量(PAF)、支气管动脉血流量(BAF)及灌注指数[PI,PI=PAF/(PAF+BAF)];然后分别从重力方向(腹侧、中间、背侧)和非重力方向(上部、中间、下部)评价,各个区域均选择连续3个层面的图像进行测值,分别获得每个区域的平均灌注参数(PAF、BAF、PI值)。用单因素方差分析正常组肺实质重力与非重力方向各个区域肺灌注的差异。结果本研究每位受检者总的辐射剂量为4.02 m Sv。正常肺实质组灌注参数PAF在重力方向腹侧、中间、背侧分别为(123.2±32.9)ml·min^(-1)·100ml^(-1)、(137.1±33.6)ml·min^(-1)·100ml^(-1)、(158.5±38.7)ml·min^(-1)·100ml^(-1);PAF在重力方向差异有统计学意义(F=13.29,P<0.001),但BAF、PI差异无统计学意义。非重力方向上部、中间、下部PAF、BAF、PI差异均存在统计学意义(P<0.05),但两两比较,各个参数仅下部与上部差异有统计学意义(P<0.05)。结论 320排低剂量CT灌注成像技术能从定量角度评估肺实质肺循环和体循环血流构成比情况。正常肺实质主要由肺循环肺动脉供血,大约为98.76%,体循环支气管动脉供血所占比例较小,PAF、BAF均受重力及血流分布影响。Objective To study the ratio changes of systemic circulation and pulmonary circulation blood flow of the lungs in normal subjects,and compare the perfusion parameters among the normal in a different district. This is done to explore the feasibility and superiority of low-dose CT pulmonary perfusion by using the 320-detector row dynamic volumetric CT. Methods A total of 20 patiens in our hospital were collected from 2014 May to 2015 January. A Toshiba 320-detector row dynamic volumetric CT scanner（ Aquilion One,Japan Toshiba medical device company） was used for lung volumetric scan in this study and with scanning parameters of 80 k V,70 m A current,and AIDR image reconstruction. The volume data was processed with the image post-processing software,and 4 time-density curves were produced,meanwhile the time to peak（ TTP） is recorded. In order to evaluate from the gravitational（ ventral,middle,dorsal） and non-gravitational direction（ upper,middle and lower）,the regions of interest in the various places were selected,and finally the lung parenchyma pseudo color perfusion images were displayed,which revealed the pulmonary artery flow（ PAF）,bronchial artery flow（ BAF） and perfusion index[PI = PAF /（ PAF ＋ BAF） ]. We selected each region to measure at three consecutive levels and respectively achieved average perfusion parameters（ PAF,BAF,PI） in every region. The statistical analyses of the data obtained from above were performed to analyze the difference in perfusion of various regions in normal subjects from the gravitational and non-gravitational direction with the single-factor analysis of variance. Results The total radiation dose was 4. 02 m Sv per subject. There was visible difference in PAF in the direction of gravity in the normal lung parenchyma group（ F = 13. 29,P = 0. 00）,PAF was 123. 2 ± 32. 9,137. 1 ± 33. 6,158. 5 ± 38. 7 ml·min- 1·100ml- 1from ventral to dorsal respectively and there was a significant statistical difference between each other,but there was no obvi

关 键 词：320排CT 肺灌注 肺循环 体循环 辐射剂量 

分 类 号：R816.4[医药卫生—放射医学]