CT肺动脉成像诊断肺栓塞的读片者一致性研究

Study of Interreader and Intrareader Agreement in the Diagnosis of Pulmonary Embolism Using CT Pulmonary Angiography

目的：评价CT肺动脉成像（CTPA）诊断肺栓塞（PE）时,不同经验的读片者间和同一读片者内的一致性。方法：55例临床可疑PE患者,作了CTPA检查,6位不同经验的放射科医生独立地分析CTPA图像来评价读片者间的一致性。3位放射科医生3个月后第二次分析CTPA图像来评价读片者内的一致性。PE的表现分为阳性、阴性和难以确定。读片者一致性用百分比及Kappa系数表示。结果：6位读片者判定29～31例（平均29.2例）患者CTPA为PE阳性,1～5例（平均3.0例）患者CTPA为难以确定。6位读片者在48例（87.3%）患者CTPA的诊断上取得一致意见,5位读片者在4例患者（7.3%）的诊断上取得一致意见,4位读片者在2例患者（3.6%）的诊断上取得一致意见,3位读片者在1例患者（1.8%）的诊断上取得一致意见。在诊断PE上,如果以每例患者为观察单位,读片者间的一致性“非常好”（Kappa值为0.91）。以每个肺动脉为观察单位,读片者间的一致性“好”（85%,Kappa值为0.74）;以肺叶动脉为观察单位,读片者间的一致性“好”（89%,Kappa值为0.78）;以肺段动脉为观察单位,读片者间的一致性“中等”（75%,Kappa值为0.59）。如果以每例患者为观察单位,同一读片者内的平均一致性“非常好”（96%,Kappa值为0.93）。结论：在CTPA上诊断PE时,经验不同的读片者间和同一读片者内的一致性均较好。

Objective：The aim of this study was to evaluate interreader and intrareader agreement in the diagnosis of pulmonary embolism using CT pulmonary angiography （CTPA） among observers with variable experience. Methods： Fiftyfive patients clinically suspected of having pulmonary embolism have undergone CTPA examinations. These images were interpreted independently by six radiologists. After three months, the images were interpreted a second time by three radiologists to assess intrareader agreement. Findings for pulmonary embolism were categorized as positive,negative,or indeterminate （equivocal） at the main,lobar,and segmental pulmonary artery levels. Agreement was assessed using percent of agreement between interpreters and by the kappa coefficient. Results：The six observers interpreted 29～31 （mean,29.2） CTPA as positive for pulmonary emholism and one to five （mean,3.0） as indeterminate. Agreement occurred among six observers in 48 patients （87.3%） ,among five observers in four patients （7.3%） ,among four observers in two patients （3.6%） ,and among three observers in one patient （ 1.8% ）. On a per-patient basis,interreader agreement was very good （Kappa, 0.89） for the diagnosis of pulmonary embolism. Agreement on a per-artery basis for all arteries was moderate （68% ; Kappa, 0.57） ;for lobar arteries was good （86% ;Kappa,0.76） ;and for segmental arteries was moderate （61% ;Kappa,0.51）. On a per-patient basis, mean intrareader agreement was very good （ 95% ; Kappa, 0.90）. Conclusion ： On the CTPA, interobsrver and intrareader agreement in the diagnosis of pulmonary embolism is very good among radiologists with a wide variety of experience.