Accuracy of 3D CE-MRA combined with ultrasound microbubble angiography for the diagnosis of lower extremity atherosclerotic occlusion.

Abstract

Objectives: To evaluate the diagnostic performance of 3D contrast-enhanced magnetic resonance angiography (3D CE-MRA) and ultrasound microbubble angiography, individually and combined, using digital subtraction angiography (DSA) as the gold standard.

Methods: This retrospective study included 60 patients diagnosed with lower extremity arterial stenosis occlusion (LEASO) from October 2019 to July 2022. All patients underwent 3D CE-MRA and ultrasound microbubble angiography, collectively assessing 470 arterial segments. The diagnostic accuracy, sensitivity, and specificity of 3D CE-MRA, ultrasound microbubble angiography, and their combination were evaluated compared to DSA findings. Kappa statistics were used to analyze the consistency of combined diagnostic efficacy.

Results: The cohort included subjects aged 56 to 85 years, with a mean age of 65.42 ± 12.65 years. The diagnostic accuracy of 3D CE-MRA was 91.70%, with sensitivity and specificity of 99.72% and 65.49%, respectively. Ultrasound microbubble angiography revealed an 87.66% accuracy with sensitivity and specificity of 99.13% and 56.35%, respectively. When combined, the diagnostic accuracy was improved to 96.17%, maintaining a sensitivity of 100%, although specificity decreased to 50.44%. The Youden index improved to 96.17%, and the Kappa value of 0.951 indicated excellent agreement, demonstrating superior performance over individual modalities.

Conclusion: The combination of 3D CE-MRA and ultrasound microbubble angiography exhibits enhanced diagnostic precision for detecting and grading LEASO compared to either modality alone. Despite reduced specificity, the combined approach increases overall diagnostic efficacy, advocating its potential for more comprehensive clinical evaluations. Further studies are warranted to confirm these findings and assess their clinical implications.