Color Doppler Ultrasound with Superb Microvascular Imaging Compared to Contrast-enhanced Ultrasound and Computed Tomography Angiography to Identify and Classify Endoleaks in Patients Undergoing EVAR

Background The aim of the study was to evaluate the diagnostic effectiveness of color Doppler ultrasound (CDUS) with superb microvascular imaging (SMI) compared to contrast-enhanced ultrasound (CEUS), computed tomography (CT) multislice angiography (64 slices), and angiography required for therapeutic reasons, for follow-up after endovascular aneurysm repair (EVAR). Methods From March 2014 to May 2015, 57 patients treated with EVAR were evaluated with CT, CEUS, CDUS, SMI, and angiography in cases requiring treatment. Evaluation included sac diameter, stent-graft integrity, identification, and classification of endoleaks. Sensitivity, specificity, accuracy, and negative and positive predictive values were evaluated for each modality of endoleak identification. Results Eight endoleaks (16.3%), all type II, were documented. Sensitivity of CT, CEUS, CDUS and SMI was 88%, 100%, 63%, and 75%, respectively. Specificity of CT, CEUS, CDUS, and SMI was 100%, 100%, 96%, and 98%, respectively With SMI, CDUS sensitivity significantly increased, whereas specificity did not register great differences. Conclusions SMI was more accurate than CDUS but less accurate than CEUS and CT to identify endoleaks after EVAR. SMI could be concretely used in the follow-up phase to increase CDUS accuracy especially in patients who cannot be studied with CEUS or CT.