To investigate the role of high-frame-rate contrast-enhanced ultrasound (H-CEUS) in displaying the source artery of type Ⅱ endoleak after endovascular aneurysm repair (EVAR).

A total of nine patients after EVAR were included in the study at our hospital from the end of May to the beginning of August 2020. All of the patients were suspected of having type Ⅱ endoleak according to conventional ultrasound. The patients were evaluated by conventional ultrasound, conventional contrast-enhanced ultrasound (CEUS), and H-CEUS by using Mindray Resona 7 ultrasound instrument to observe whether there was endoleak and to find the source artery of endoleak. Traditional CEUS examination and H-CEUS were performed by an experienced physician to observe the time to display the stent and aneurysm cavity to calculate the time difference and to find the source artery. Dynamic and static images were preserved and reviewed by two other experienced ultrasound physicians, and scored according to the identifiability and image quality of the two angiographic sources. Paired sample t test was used to compare the difference of the peak velocity in the direction of inflow and the maximum velocity in the direction of outflow. Wilcoxon signed-rank test was used to compare the difference of imaging quality score of source arterial imaging by conventional CEUS with that of H-CEUS.

The average size of the abdominal aortic aneurysm was (5.2±1.1) cm, and there was no obvious aneurysm growth in all patients. One patient recovered 3 months after EVAR. There was no endoleak in one of the nine patients, which was false positive finding by color Doppler ultrasound. Eight cases of endoleak found by color Doppler ultrasound were confirmed by CEUS. Eight cases were diagnosed with type Ⅱ endoleak, of which three were from a single artery, and the remaining five were from more than two arteries. The endoleak originated from the inferior mesenteric artery (IMA) and/or lumbar artery (LA). Color Doppler ultrasound showed 13 arteries, but CEUS found 15 arteries. The median of image quality score of endoleak source artery was 1.0 for conventional CEUS and 3.0 for H-CEUS, and there was a significant difference between them (Z=-3.035, P=0.002).

In the diagnosis of type Ⅱ endoleak after EVAR, H-CEUS can more clearly show the source artery than the traditional CEUS.