Diagnostic imaging in patients after endovascular aortic aneurysm repair with special focus on ultrasound contrast agents

INTRODUCTION Endovascular treatment of abdominal aortic aneurysms (AAAs) constitutes an alternative to the classic surgical approach. The procedure may be associated with specific complications, including persistent flow within the aneurysm sac, otherwise known as endoleak.
OBJECTIVES The aim of the study was to assess the utility of ultrasound contrast agents in the diagnosis of endoleaks after endovascular AAA repair.
PATIENTS AND METHODS A total of 198 patients with AAA underwent endovascular treatment. Follow‑up examinations were performed at 6 and 12 months after the procedure, including pre- and postcontrast ultrasound, followed by computed tomography angiography (CTA) as a reference. Each ultrasound examination consisted of B‑flow, color, and power Doppler evaluation before and after contrast injection, supplemented by a contrast‑enhanced ultrasound (CEUS) scan.
RESULTS At 6 months, endoleaks were diagnosed in 16 and 22 patients during pre- and postcontrast ultrasound, respectively. CEUS confirmed the presence of 22 previously diagnosed and 4 new (type II) endoleaks. At 12 months, endoleaks were detected in 7 and 13 patients by means of pre- and postcontrast ultrasound, respectively. CEUS confirmed the presence of endoleaks in 17 patients. None of the endoleaks diagnosed solely with CEUS at 6 and 12 months were detected by CTA.
CONCLUSIONS Contrast agents substantially increase the sensitivity of ultrasound in the diagnosis of endoleaks, particularly type II. CEUS proved to have the highest sensitivity for the diagnosis of endoleaks by revealing pathologies undetected by other modalities, including CTA. CEUS may substitute CTA in surveillance of patients after stent graft deployment.