The Evaluation Value Of 256-Slice Spiral CT 3D Angiography After Lower Extremity Artery Stent Implantation

Objective: Digital subtraction angiography(DSA)was used as the "gold standard" to explore the diagnostic value of philips 256-slice spiral CT three-dimensional angiography(3d-cta)in evaluating the degree of stent stenosis after lower extremity artery stent implantation.Methods: A total of 44 patients who underwent interventional treatment and lower limb stent implantation and were reviewed in the fourth affiliated hospital of China medical university from April 2016 to January 2019 were collected.A total of 56 stents were included(multiple stents connected as a set of stents): 36 males and 8 females,aged45-92 years,with an average age of 71 years,and 1.5 months to 9 years after stent implantation.CTA examination was performed first,followed by DSA examination within 1 week.The original CT scan data was uploaded to the philips post-processing workstation for post-processing analysis,and image row volume reconstruction(VR),maximum density projection(MIP),multi-plane reconstruction(MPR)and curved surface reconstruction(CPR)were performed,respectively.The degree of stenosis in the lower extremity artery stent was observed and measured,and compared with the degree of the corresponding segment DSA stenosis.DSA was used as the "gold standard" to calculate the overall coincidence rate of CTA in judging the degree of stent stenosis and the diagnostic coincidence rate of different degrees of stenosis.SPSS22.0 statistical software package was used to analyze the data.Kappa consistency test was conducted on the stenosis degree in the stent shown by DSA and CTA,and Kappa value(represented by K value)was calculated.For the measurement data,if they follow normal distribution and have homogeneity of variance,paired sample t test is adopted.In case of non-normal distribution,Wilcoxon’s symbolic rank sum test for paired samples was used,and the test level was set as =0.05.When P<0.05,the difference between the two was considered statistically significant.Results: 1.K =0.845 obtained by Kappa consistency test,suggesting that the two methods of CTA and DSA have a good consistency in the determination of the degree of stenosis in lower limb artery stents.Compared with DSA,the overall coincidence rate of CTA for the degree of stenosis in lower limb artery stents was 89.3%(50/56).The coincidence rate of mild stenosis in lower limb artery stent was 85.7%(6/7).The coincidence rate of moderate stenosis in lower limb artery stents was 60.0%(6/10).The coincidence rate of severe stenosis in lower limb artery stents was 100.0%(9/9).The coincidence rate of complete occlusion was 100.0%(27/27).2.Compared with DSA,the measurement value of CTA for the stenosis rate in lower limb artery stents was higher.Conclusions: 1.Philips 256-slice spiral CT three-dimensional angiography has a high diagnostic accuracy in evaluating the degree of stenosis after lower limb artery stenting,which can be used as a follow-up examination for patients after lower limb artery stenting,and can also provide imaging basis for clinicians to formulate clinical treatment plans.2.Compared with DSA,the measurement value of CTA for the stenosis rate in lower limb artery stents was higher.3.To some extent,CTA can provide more comprehensive intravascular information than DSA.