双源计算机断层摄影术双能量肺灌注成像与肺动脉造影诊断肺栓塞的对比研究

Comparative Study for Diagnostic Value Between Dual Energy CT Lung Perfusion Imaging and CT Pulmonary Angiography in Patients With Pulmonary Embolism

目的:与计算机断层摄影术肺动脉造影(CTPA)比较,探讨双源计算机断层摄影术(CT)双能量肺灌注成像(DEPI)对肺栓塞的诊断价值。方法:49例疑似肺栓塞患者进行DEPI扫描,最终19例CTPA确诊肺栓塞的患者纳入研究。以80 k V的数据得到CTPA图像,采用肺灌注成像软件(Lung PBV)后处理得到DEPI图像,以肺段为单位观察CTPA图像上肺栓塞的位置、类型,DEPI图像上肺灌注缺损的位置及形态,并对两者的类型进行相关性分析,计算CTPA与DEPI诊断肺栓塞的一致性,并对不一致的原因进行分析。结果:380个肺段,CTPA检出162个肺段有肺栓塞,DEPI检出155个肺段有灌注缺损或降低,部分型肺栓塞主要为斑点状、斑片状灌注缺损或无缺损,完全型肺栓塞则以段或亚段分布的灌注缺损为主,两者存在相关性(χ2=305.5,P=0.000)。CTPA与DEPI诊断肺栓塞的符合率为83.42%,KAPPA系数值为0.659。结论:DEPI的表现与CTPA上肺栓塞的程度及类型有关,两者联合有助于肺栓塞的诊断。

Objective： To explore the value of dual energy CT lung perfusion imaging （DEPI） for diagnosing pulmonary embolism （PE） in comparison with CT pulmonary angiography （CTPA）. Methods： There were 49 patients with suspected PE received DEPI scanning and 19 with CTPA conifrmed diagnosis were enrolled in this study. CTPA image was obtained by 80 kv data, and DEPI image was obtained by PBV software. The location, type of PE in CTPA image, and the location, shape of perfusion defect in DEPI were observed and compared by segment basis. The correlation and agreement of CTPA and DEPI for diagnosing PE were calculated and the un-agreement was analyzed. Results： A total of 380 segments were included for analysis. CTPA detected 162 segments of PE and DEPI detected 155 segments of perfusion defect or reduction, partial PE were mainly presented by perfusion defects as speckles, patches or without perfusion defect, and complete PE were mainly showed segmental or sub-segmental perfusion defects. CTPA and DEPI were correlated for PE diagnosis （χ2=305.5,P=0.000）, the diagnostic agreement was 83.42% and KAPPA value was 0.659. Conclusion： The perfusion defect in DEPI is related to the degree and type of PE presented in CTPA, their combination is helpful for diagnosing PE.