The Auxiliary Value Of Dual Energy CT Pulmonary Perfusion Imaging In The Diagnosis Of Pulmonary Embolism

PurposeIn the application of dual energy scanning mode for CTPA in the diagnosis of pulmonary embolism,whether DEPI image can provide more diagnostic information and improve the positive detection rate of pulmonary embolism.Materials and MethodsThis study included 93 patients who underwent dual source CT pulmonary angiography in China-Japan Friendship Hospital Affiliated Jilin University from April 2019 to January 2020.Two doctors with 5 years of imaging diagnosis experience judged the existence of pulmonary embolism through CTPA images,and recorded the number,level and type of embolism in patients with pulmonary embolism.Then,the lung perfusion images of 93 patients were interpreted to determine whether there was perfusion defect,and the perfusion defects were classified and recorded.The embolism in CTPA images was compared with the perfusion defect in DEPI images.When the two doctors have different opinions,the final decision will be made after consultation with another senior doctor.Finally,according to the control results,we compared the detection rate of pulmonary embolism between single CTPA image and combined DECT lung perfusion image.ResultsThrough the CTPA images of 93 patients,30 patients were diagnosed with pulmonary embolism,a total of 201 embolism were found.In 93 patients,219 perfusion defects were found by DEPI images,of which 94 perfusion defects did not conform to the characteristics of vascular embolism,that is,125 perfusion defects were considered to be caused by pulmonary embolism.The emboli in CTPA images were compared with those in DECT lung perfusion images.It was found that102 embolism in 125 perfusion defects were found in the first interpretation of CTPA images,while 19 embolism in 19 perfusion defects were found in the review of CTPA images,and no embolism in 4perfusion defects were found.The 19 newly discovered embolism were all obstructive subsegmental embolism,belonging to 15 different patients.Among them,9 patients had been diagnosed with pulmonary embolism because of emboli in other locations at the first interpretation of CTPA images.That is to say,6 patients were re diagnosed with pulmonary embolism with the help of DECT pulmonary perfusion images,After statistical analysis,it is found that the improvement of diagnosis rate is significant.ConclusionDECT iodine map can provide more accurate diagnostic information for PE and improve its detection rate.