Which mode of color Doppler ultrasound is most suitable for detecting endoleaks in surveillance after endovascular aneurysm repair?

Abstract

Objectives: The aim of this study was to evaluate the best mode of Doppler ultrasound, blood flow imaging (BFI) versus color Doppler ultrasound (CDUS), in detecting endoleaks diagnosed using computed tomography angiography (CTA). Patients and methods: A total of 70 consecutive patients (60 males, 10 females; mean age: 68.5±7.8 years; range, 48 to 82 years) undergoing standard EVAR procedure were retrospectively evaluated in the outpatient clinic following CTA between January 2018 and December 2019. Ten (13.9%) patients in which endoleaks were detected were also evaluated using CDUS which was performed by two radiologists specializing in Doppler ultrasound. The radiologists were blind to CTA reports. A reporting protocol was developed for endoleak detection using different modes of CDUS (BFI vs. CDUS). Results: Of all cases, 10 (13.9%) endoleaks were detected using CTA. All five type I and III endoleaks requiring an intervention were detected by both modes of CDUS, while four of the five type II endoleaks were not. The single case of type II endoleak was suspected following the visualization of fresh thrombus formation. There was an inadequacy in detecting low flow endoleaks both using BFI and standard color Doppler mode. There was a strong correlation between the aneurysmal sac diameters measured using CTA and CDUS. Conclusion: The CDU and BFI are capable of detecting type I and III endoleaks with similar sensitivity and specificity. These modes should be used in combination as confirmatory tests. For surveillance, CDUS promises accurate results without missing any potential complication requiring an intervention. Lack of detecting type II endoleaks may be negligible, as sac enlargement is the key for reintervention in this case.