Feasibility Study Of Dual Energy CT Perfusion Imaging For Assessment Of Acute Pulmonary Embolism

ObjectiveTo evaluate the application value of dual energy perfusion imaging(DEPI) and CT pulmonary angiography(CTPA) of dual-source CT(DSCT) in the diagnosis of pulmonary embolism in rabbits.MethodsTen rabbits were cathetered into inferior vena cava via the right ventricle to bilateral pulmonary artery, and were injected the gelatin sponge. Acute pulmonary embolism model was made. Digital subtract angiography(DSA) and DSCT scans were performed. Postprocessing imaging including CT angiography(CTA) and DEPI were carried out at the workstation. The rabbits were killed immediately after DSCT scan. The location and number of the lung lobes with pulmonary embolism were evaluated pathologically. RV/LV value was also calculated before and after embolism.Results1,Compared with pathology, the sensitivity and specificity of DSA,CTA,DEPI were 90.5% and 100%,71.4% and 100%,85.7% and 92.9% respectively. The kappa value were 0.884,0.667 and 0.767. DEPI and DSA showed excellent correlation with pathology, CTA indicated moderate correlation with pathology. On DEPI, the region of PE displayed low perfusion area, and the region of NPE showed normal perfusion area. 2,Right ventricular to left ventricular diameter ratio after embolism was higher than before embolism(P<0.05).ConclusionDEPI had good correlation with pathology and displayed the functional information of lung. Therefore, acquisition of perfusion images with dual energy CT may be helpful for assessing acute pulmonary embolism. ObjectiveTo prospectively evaluate the feasibility of dual-source computed tomography dual energy perfusion imaging (DEPI) for assessment of the severity of acute pulmonary embolism (APE).MethodsTwenty-four patients who underwent dual-source computed tomography (DSCT) scan were analyzed by Lung PBV software. Computed tomography pulmonary angiography (CTPA) and DEPI were obtained. Dual energy CT pulmonary perfusion defect index, CT pulmonary angiographic obstruction index, and right ventricular maximal short axis to left ventricular maximal short axis ratio (RV/LV) were separately calculated by DEPI and CTPA. Spearman correlation coefficient was used to assess the correlation of three indexes. The difference of three indexes was compared between severe APE group and non-serious APE group.ResultsThere were 24 cases of APE, in which 9 cases were severe and 15 cases were non-serious. The median of perfusion defect index, obstruction index and RV/LV in severe APE group was separately 32.5% (15.0%-62.5%), 45.0% (27.5%-75.0%) and 1.16 (1.04-1.45), while non-serious group was separately 12.5% (0-37.5%), 12.5% (2.5%-42.5%) and 1.03 (0.85-1.41). The perfusion defect index, obstruction index and RV/LV of two groups existed statistical difference (P<0.05). The perfusion defect index, obstruction index and RV/LV of severe APE group were higher than those of non-serious APE group. Perfusion defect index had moderate correlation with RV/LV (r=0.635, P=0.001<0.05). Perfusion defect index had good correlation with CTPA obstruction index (r=0.790, P=0.000<0.05).ConclusionDEPI of the dual-source CT is feasible to assess the severity of acute pulmonary embolism.