The Evaluation Of Diagnostic Accuracy Of Coronary Artery Calcified Plaque Stenosis With Dual Energy Subtracted Of DSCT

Objective: To evaluate the accuracy of dual-energy subtraction and conventional post-processing in the diagnosis of coronary artery stenosis caused by calcified plaque by comparing coronary angiography(CAG),the gold standard of coronary artery examination.Methods: 30 patients with suspected or confirmed coronary heart disease(107 stenosis caused by coronary artery calcification plaque)underwent coronary angiography(CAG)and dual source computed tomographic angiography(DSCTA)within 15 days.The second generation dual-source CT(SOMATOM Definition Flash CT,Siemens Healthcare)was used to perform dual-energy spiral scanning with a tube voltage of 100 k V/140 k V.The original image will be processed in SYGOMMWP VE 40 B workstation using Body Bone Removal in Dual Energy to obtain dual-energy subtraction image(bone removal and calcification).Then the dual-energy subtraction image and the original image were used in Syngo.via workstation to evaluate and measure the narrow lumen caused by calcified plaque using image post-Reconstruction processing techniques such as multiplanar reconstruction(MPR),curve planar Reconstructions(CPR)and volume rendering(VR).(1)The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of dual-source CT dual-energy subtraction were calculated by comparing the results of dual-energy subtraction and conventional post-processing with those of CAG.(2)Comparing the results of dual-energy subtraction with those of conventional post-processing methods,the difference between the two methods in the diagnosis of coronary stenosis was evaluated.Results: A total of 30 cases were included in the study,and 107 stenosis caused by calcified plaque could be evaluated and measured by CCTA.(1)The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of dual energy subtraction in the diagnosis of coronary stenosis(< 50%)were 70.9%,100.0%,100.0%,76.5% and 85.0%,respectively.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of diagnosing coronary artery stenosis less than 70% were 83.7%,96.9%,98.4%,70.9% and 86.9%,respectively.(2)The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of routine post-processing in the diagnosis of coronary artery stenosis(< 50%)were 92.7%,100.0%,100.0%,92.9% and 96.3%,respectively.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of diagnosing coronary artery stenosis less than 70% were 89.3%,87.5%,94.4%,77.8% and 88.8%,respectively.(3)Compare the results of conventional post-processing and dual-energy subtraction in the diagnosis of stenosis(< 50%)and(< 75%).2 test was used to compare the results.When the degree of stenosis was less than 50%,the difference was statistically significant(p < 0.05).When the degree of stenosis was less than 75%,the difference was not statistically significant.Conclusion: Compared with gold standard CAG,dual-energy subtraction is more accurate in evaluating the degree of coronary stenosis,and can be used to display coronary artery and evaluate the degree of stenosis.For moderate stenosis of coronary artery,dual-energy subtraction and conventional post-processing methods have higher diagnostic accuracy.For mild stenosis of coronary artery,dual-energy subtraction has the possibility of overdiagnosis,so its diagnostic ability is slightly lower than conventional post-processing methods.