Clinical Research:diagnostic Evaluation Of Non-thrombotic Iliac Vein Compression Lesions By CDFI And CEUS

Objective:The purpose of this study was to analyze and compare the diagnostic efficacy of color Doppler flow imaging ultrasound(CDFI)with contrast-enhanced ultrasound(CEUS)for non-thrombotic iliac vein compression lesions(NIVCL),explore the clinical value of CEUS in diagnosing NIVCL,and further improve the clinical targeting in selecting imaging diagnostic modalities.Methods:A total of 68 patients at C3 and above levels were selected and enrolled from June2021 to January 2023 at the Department of vascular surgery in Shanxi Provincial People’s Hospital,according to the C-grading scale in the CEAP classification combined with symptoms and signs.Sex,age,BMI as well as other influencing factors of NIVCL were collected from all enrolled patients to perfect the related examinations.After signing informed consent with the patients,the four examinations including gray-scale ultrasound,CDFI,CEUS and XRV were sequentially refined,and the eligible cases with imaging findings were enrolled by two vascular surgeons with more than 10 years of working experience in double-blind interpretation of the examination results with two ultrasound doctors.Using XRV examination as the standard and the degree of iliac vein stenosis(DSR)≥50%as the diagnostic criterion,the enrolled patients were divided into NIVCL and non NIVCL groups,and the positive diagnostic rate,the detection rate of collateral circulation formation and reverse flow of the internal iliac vein between CDFI and CEUS,and the measured reference vessel diameter(RVD)were statistically analyzed.Univariate logistic regression analysis was performed for the incidence factors of NIVCL,and on the basis of this,multivariate logistic regression analysis was performed to establish a risk prediction model,and ROC curves were constructed to evaluate the prediction models.Results:Using XRV as the standard,CDFI Diagnosis had a sensitivity of 72.73%,specificity of 100%,accuracy of 82.35,and Youden index of 72.73%;The sensitivity of CEUS diagnosis was 90.91%,specificity 100%,accuracy 94.12,and Youden index 90.91%;The sensitivity of the combined diagnosis of the two was 90.91%,specificity 100%,accuracy94.12,and Youden index 90.91%.Chi square analysis showed that the diagnosis of the two combined was more effective than that of CDFI(X~2=42.311,P<0.001),and the diagnostic efficacy of the two combined was the same as that of CEUS.With XRV diagnosis as the standard,CDFI had a sensitivity of 63.6%(28/44)and specificity of100%(24/24)for diagnosing intra iliac regurgitation;CEUS had a sensitivity of 45.4%(20/44)and a specificity of 100%(24/24)for the diagnosis of internal iliac regurgitation;CDFI had a sensitivity of 55.6%(20/36)and a specificity of 100%(32/32)for diagnosing collateral circulation;CEUS had a sensitivity of 100%(36/36)and a specificity of 100%(32/32)for the diagnosis of collateral circulation.The RVD between the RVD measured by CDFI and that measured by XRV was 0.031(using mean±SD);The RVD between the RVD measured by CEUS and that measured by XRV was0.008.Univariate logistic regression was performed for sex,age,BMI,CEAP grade,VCSs,Villalta scale,maximum flow rate at the tested reflux of saphenous vein valve,maximum flow rate at the tested reflux of saphenous vein,and BMI,Villalta scale,maximum flow rate at the tested reflux of saphenous vein,maximum flow rate at the tested reflux of saphenous vein valve,and four variables were statistically significant.The above 4 variables were incorporated into the multivariate logistic regression model,and nomogram plots were drawn.Multivariate results showed that the Villalta scale,the widest saphenous vein,and the maximum flow velocity at the valve sparing test reflux of the saphenous vein were all risk factors for morbidity.The optimal cutoff value of the nomogram score was determined to be 0.9862 based on the Youden index,at which point the maximum value of the Youden index was 0.726.A ROC curve was established and the area under the ROC curve(AUC)was calculated.The AUC was calculated to be0.864 with a 95%confidence interval(95%CI)of(0.773,0.954).And the calibration curve of the model was plotted,and the calibration curve showed that the model prediction performance was good.Conclusion:CDFI combined with CEUS has good diagnostic efficacy in the diagnosis of NIVCL,and its diagnostic value is better than that of CDFI,CEUS alone for the diagnosis of NIVCL,which is a diagnostic modality that takes both safety and high accuracy.Among them,CEUS is more similar to XRV defined as the“gold standard”in terms of the efficacy of collateral circulation at diagnosis and the measured diameter of the iliac veins.The difference between the diameter of iliac veins measured by CDFI,CEUS and RVD measured by XRV is not clinically significant and can be used as a reference for clinical diagnosis.BMI,the widest point of the great saphenous vein,and maximal flow velocity at the valve poor test reflux of the saphenous vein were all independent risk factors for the development of NIVCL,and the Villalta scale can serve as an effective indicator for evaluating the paroxysm of NIVCL.The nomogram model for NIVCL has good predictive performance and can assist clinicians in assessing whether patients with chronic venous insufficiency require further morphologic examination of the iliac veins.