Three-Dimensional Contrast-Enhanced Ultrasound Improves the Detection and Classification of Endoleaks Following Endovascular Aneurysm Repair

Background and objectives: Three-dimensional contrast-enhanced ultrasound (3D-CEUS) is a novel technology allowing surgeons to view duplex ultrasound images in 3-D with ultrasound contrast highlighting blood flow in endoleaks following EVAR. It potentially reduces the need for computed tomographic angiography (CTa) and catheter angiography. This study compares 3D-CEUS with both CTa and the final vascular multi-disciplinary team (MDT) diagnosis using all available imaging. Inter-operator variability for detection of endoleak and the influence of 3D-CEUS on patient management were studied.
Methods: One hundred consecutive patients undergoing CTa for EVAR surveillance were invited to undergo standard CEUS and 3D-CEUS on the same day with 3D-CEUS reported independently by two blinded vascular scientists. Presence and type of endoleak was compared between CTa, standard CEUS, 3D-CEUS and the final diagnostic decision made in the vascular MDT meeting. Inter-operator reliability of 3D-CEUS was analysed using the kappa statistic.
Results: 100 paired CTa, CEUS and 3D-CEUS studies were analysed. When compared with CTa, the sensitivity, specificity, positive, and negative predictive value of 3D-CEUS to endoleak was 96%, 91%, 90%, and 96% respectively. When compared with the MDT decision with access to all imaging modalities, the sensitivity, specificity, positive, and negative predictive value of 3D-CEUS was 96%, 100%, 100% and 96%. The kappa statistic for inter-operator agreement was 0.89.

Conclusions: 3D-CEUS was more sensitive and accurate than CTa for endoleak detection and classification following EVAR. 3D-CEUS is now our initial investigation of choice in cases of sac expansion during duplex follow-up or diagnostic uncertainty on standard duplex or CTa.