Purpose: We assessed whether contrast enhanced ultrasound (CEUS) could provide clinically meaningful data by diagnosing and classifying endoleaks in patients with endovascular aortic aneurysm repair (EVAR) when evaluation on standard of care imaging is limited.
Materials and methods: A single-center retrospective review of patients with EVAR who underwent both standard of care imaging and CEUS from February 2023 to September 2023 was conducted. Standard of care imaging was defined as CT angiography and non-contrast CT to account for patients in whom contrast-induced nephropathy was a concern. Seven patients (median age 82, range 69 - 89) were identified. Median time elapsed between EVAR and presentation for CEUS was 10 years (range 2 - 15) and four subjects had prior endoleak repairs (one type IA, three type II, one type IIIA, one type IIIB). CEUS was conducted an average of 5.6 days (range 1 - 16) after initial CT scan. All CEUS scans were performed and interpreted by two operators, board-certified in Interventional Radiology, using Lumason (Bracco, Italy) contrast. Results of standard of care imaging, CEUS and subsequent interventions were recorded.
Results: All initial CT imaging detected expansion of the aneurysm sac (n=7, 100%), and endoleak was diagnosed in over half the cases (n=4, 57%). Of these, none were able to be definitively subclassified. Subsequent CEUS were all technically successful and no adverse events were reported. Two studies did not detect any endoleak which correlated with the prior CTA scans. Both subjects were recommended to continue regular surveillance screening. One patient underwent angiography after CEUS, which confirmed the findings. The remaining five studies were able to diagnose endoleaks and further classify them into type II (n=2), type III (n=2), and type IA/gutter type A1 (n=1). Based on this information, the type II and type III leaks were repaired by IR and Vascular Surgery respectively. The subject with a type IA/gutter type A endoleak was transferred to an outside institution for complex aortic repair. All completed angiograms confirmed the classification made on CEUS (n=5, 100%).
Conclusion: CEUS was able to confirm the presence or absence as well as the type of endoleak in all patients with equivocal standard of care imaging. This had important implications for patient management plans, by limiting unnecessary interventions and by facilitating decisions about how to approach the necessary interventions.