Objective To assess the diagnostic value of dual energy pulmonary perfusion imaging(DEPI)for pulmonary embolism.Methods The clinical data of 87 patients with suspected pulmonary embolism who had received DEPI between August 2017 and July 2018 in Jiaxing Second Hospital were retrospectively analyzed.With the findings of CT pulmonary angiography(CTPA)as the reference standard and with patients and pulmonary lobes as evaluation units,respectively,a diagnostic test was performed to calculate the diagnostic coincidence rate,sensitivity,specificity,positive predictive value,negative predictive value,Youden index,positive likelihood ratio,negative likelihood ratio,and Kappa coefficient value for the diagnosis of DEPI and CTPA.Results The coincidence rate,sensitivity,specificity,positive predictive value,negative predictive value,Youden index,positive likelihood ratio,and negative likelihood ratio were 85.06%,88.41%,72.22%,92.42%,61.90%,0.61,3.18,and 0.16,respectively,when applying the patients as evaluation units.When the pulmonary lobes were invoked as evaluation units,the above-mentioned indexes were 89.57%,76.80%,96.82%,93.20%,88.02%,0.74,24.15,and 0.24,respectively.The diagnostic results of DEPI and CTPA had a good and excellent consistency,respectively(Kappa value=0.571,0.765).Conclusions DEPI has high accuracy,sensitivity,and specificity in the detection of pulmonary embolism.The combination of DEPI with CTPA can simultaneously obtain the anatomical structure and functional information images,greatly improving the diagnostic accuracy for pulmonary embolism.Thus,it can be used as the preferred examination for patients with clinically suspected pulmonary embolism.
Keywords: dual energy pulmonary perfusion imaging; dual source CT; pulmonary angiography; pulmonary embolism.