The Application Value Of Energy Spectrum CT Single Energy CTPA And LPBV Technology For Pulmonary Embolism

Objective: To explore the evaluation of dual-energy computed tomography pulmonary angiography(DE-CTPA)and lung perfused blood volume(LPBV)on the severity and blood perfusion of pulmonary embolism(PE)and the correlation between both technics.Methods: A total of 198 patients with suspected PE were included from June 2018 to January 2020.GE Revolution CT was used to scan to obtain single-energy CTPA and LPBV-related images.We analyzed the number,position and feature of pulmonary embolization and record and compare the iodine content in the embolization area of different types of CTPA.The relationship between PE index derived from DE-CTPA and perfusion defect index derived from Iodine perfusion maps were assessed.Results:(1)199 pulmonary embolization in 37 patients were found.Among them,there were 183 embolization in the middle and sub-segments,12 embolization in the lobe pulmonary arteries,and 4 embolization in the pulmonary trunk;118 complete embolization,12 floating embolization,59 eccentric embolization,and 10 mural embolization.The results of DE-CTPA were highly consistent with iodine perfusion maps.The sensitivity was95.0%,the specificity was 90.1%.(2)The iodine content in the embolization area of different types of embolization was significantly different(P <0.05).The iodine content of the embolization area of complete emboli was significantly lower than that of floating embolization,and the iodine content of floating embolization was significantly lower than that of eccentric embolization and mural embolization.There were also significant statistical differences between eccentric embolization and mural embolization(P < 0.05).However,the content of iodine-based material in mural embolization was close to the content of normal lung tissue(P > 0.05).(3)There were statistical differences between the complete and incomplete embolization in the iodine perfusion maps(P < 0.05),in which the complete embolization all showed perfusion defects,but some of the incomplete embolization had no perfusion defects.(4)There was a good correlation between PE index derived from DE-CTPA and perfusion defect index derived from Iodine perfusion maps(R = 0.774,P < 0.05).Conclusion: DE-CTPA can effectively showed the embolization and evaluate the severity of PE patients,and LPBV images can effectively reflect the pulmonary perfusion blood volume caused by pulmonary embolism.There was a good correlation between PE index derived from DE-CTPA and perfusion defect index derived from Iodine perfusion maps.