Effectiveness of contrast‐enhanced duplex ultrasound for detecting renal artery stenosis: A systematic review

Abstract Purpose Contrast‐enhanced duplex ultrasound (CEUS) might be a useful tool to diagnosing renal artery stenosis (RAS). We amalgamated and reviewed the evidence assessing the diagnostic accuracy of CEUS on detecting RAS compared to angiography. Methods This preregistered systematic review included studies that compared the presence of RAS via CEUS with angiography. Sources were searched in November 2022 and included Scopus, EMBASE, MEDLINE, CINAHL, and Academic Search Premier ( n = 1717). The Quality Assessment of Diagnostic Studies 2 tool assessed study quality. Results are presented narratively. Results The studies included ( n = 11) had a total of 447 unique participants (193 females) and average age of 56 ± 9 years. Five of eleven studies investigated CEUS using SonoVue contrast agent and reported an average accuracy (91% ± 2%), sensitivity (91% ± 3%), specificity (90% ± 5%), negative predictive value (86% ± 6%), and positive predictive value (94% ± 1%) with all values >80%. The accuracy of CEUS using other types of contrast agent ( n = 6), including Levovsit ( n = 3/6), Definity ( n = 1/6), perfienapent emulsion ( n = 1/6), and perfluorocarbon‐exposed sonicated dextrose albumin ( n = 1/6) was mixed. These studies detected an average accuracy of 91 ± 11% ( n = 2/3% > 80%), sensitivity of 98% ± 4%, ( n = 3/3% > 80%), and specificity of 86% ± 10% ( n = 2/3% > 80%). Included studies had generally low risk of bias and applicability concerns except for unclear flow and timing ( n = 7/11) and applicability of patient selection ( n = 4/11). Conclusion Despite being limited by the heterogeneity of included studies, our review indicates a high overall diagnostic accuracy for CEUS to detect RAS compared to angiography, with the largest evidence‐base for SonoVue contrast. Radiologists and hospital decision makers should consider CEUS as an acceptable alternative to angiography.