Effectiveness of Intra-operative Contrast-Enhanced Ultrasound Assessment to Optimize Type II Endoleak Embolization

Abstract

Purpose: To analyze the effectiveness of type II endoleaks (T2E) embolization using intra-operative contrast-enhanced ultrasound (CEUS).

Methods: Consecutive patients treated for T2E underwent a standardized protocol with trans-arterial or trans-lumbar access, large volume embolization, onlay fusion, and intra-operative CEUS. Technical success was defined by exclusion of endoleak by CEUS.

Results: Twenty-six patients (mean age 81 ± 11 years old; 89% male) were treated. The mean aneurysm sac enlargement was 11 ± 8 mm from T2E diagnosis. Embolization was performed using Onyx® 18 in all patients with adjunctive coils in 13 patients (50%). After the first embolization, CEUS documented residual T2E in 13 patients (50%). Ten patients (38%) had additional embolization, which successfully eradicated the T2E in seven of them. Technical success was 50% after the first embolization attempt and 77% after additional attempts guided by CEUS (P = 0.080). There was no mortality. Median imaging follow-up was 22 months. Among the 20 patients with no residual T2E on completion CEUS, 16 (80%) had sac stabilization and none required additional interventions for T2E. Of the six patients with residual T2Es on CEUS, three had sac stabilization (50%) and one required additional reintervention for T2E. There was one late aortic rupture at 56 months.

Conclusion: One in two patients treated by T2E embolization had residual endoleak on intra-operative CEUS after a first embolization attempt, decreasing to one in four patients after multiple attempts. A negative completion CEUS following embolization was associated with higher rates of sac stabilization and no need for additional T2E embolization.

Keywords: Aortic aneurysm; Contrast-enhanced ultrasound; Intra-operative assessment; Type II endoleak; Type II endoleak treatment.