Related Experiment Videos
Contrast-enhanced ultrasound imaging for aortic stent-graft surveillance
Maria Fabrizia Giannoni1, Giovanni Palombo, Enrico Sbarigia
1Department of Vascular Surgery, University of Rome La Sapienza, Rome, Italy. mariafabrizia.giannoni@uniroma1.it
Insights
Enhanced ultrasound is a useful tool for monitoring aortic endografts after repair. It shows promise in detecting endoleaks potentially missed by other imaging methods.
Area of Science:
- Vascular Surgery
- Medical Imaging
- Radiology
Background:
- Endovascular aortic aneurysm repair (EVAR) requires long-term surveillance to monitor graft integrity and detect complications.
- Computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) are standard imaging modalities for EVAR surveillance.
- Ultrasound offers a non-invasive and potentially more accessible alternative for monitoring aortic endografts.
Purpose of the Study:
- To compare the diagnostic accuracy of unenhanced and enhanced ultrasound imaging against CTA or MRA for surveillance of aortic endografts.
- To evaluate the effectiveness of ultrasound in detecting endoleaks and assessing graft patency.
- To determine the role of ultrasound in long-term follow-up after EVAR.
Main Methods:
- Thirty patients who underwent EVAR were enrolled in a follow-up program.
- Patients underwent CTA or MRA, radiography, and unenhanced and enhanced ultrasound at 3, 12, and 24 months.
- Ultrasound findings were compared with CTA/MRA as reference standards for aneurysm diameter, endoleaks, and graft patency.
Main Results:
- Enhanced ultrasound demonstrated 100% sensitivity in detecting endoleaks, confirming all endoleaks found by CTA/MRA.
- Enhanced ultrasound identified additional endoleaks (primarily type II) not detected by CTA/MRA, though these were considered false positives.
- Aneurysm sac diameter changes were similar in patients with confirmed endoleaks and those with potential false positives, suggesting possible clinical relevance.
Conclusions:
- Enhanced ultrasound is a valuable tool for the long-term surveillance of endovascular aortic aneurysm repairs, potentially used alongside CTA or MRA.
- Enhanced ultrasound may identify endoleaks missed by conventional imaging techniques, warranting further investigation.
- Ultrasound provides a promising, non-invasive method for monitoring EVAR outcomes.
Purpose:
To compare unenhanced and enhanced ultrasound imaging to computed tomographic angiography (CTA) or magnetic resonance angiography (MRA) for surveillance of aortic endografts.
Methods:
Thirty consecutive patients (29 men; mean age 69 years, range 50-82) who underwent endovascular aortic aneurysm repair agreed to participate in a follow-up program. Patients underwent CTA (26/30) or MRA (4/30), plain abdominal radiography, and unenhanced and enhanced ultrasound examinations at 3, 12, and 24 months to evaluate aneurysm diameter, endoleaks, and graft patency. The accuracy of ultrasound was compared with CTA or MRA as the reference standards.
Results:
Twenty-six patients reached the 24-month assessment (mean follow-up 30 months, range 6-60). All endoleaks detected by CTA or MRA were confirmed by enhanced ultrasound; the aneurysm diameter in these patients remained unchanged or increased. In patients without endoleaks on any imaging method, the sac diameter remained unchanged or decreased. Endoleaks disclosed by enhanced ultrasound alone, all type II, numbered 16 at 3 months, 6 at 12 months, and 3 at 24 months. In this group, the aneurysm diameter remained unchanged or increased. Enhanced ultrasound yielded 100% sensitivity in detecting endoleaks, but compared with CTA and MRA, all endoleaks detected by enhanced ultrasound alone were false positives (mean specificity 65%). Nevertheless, because changes in the postoperative aneurysm diameter were similar in patients with endoleaks detectable on CTA/MRA and on enhanced ultrasound ("true positives") and in those with endoleaks detectable only on enhanced ultrasound ("false positives"), some endoleaks were possibly "true positive" results.
Conclusions:
Enhanced ultrasound is a useful method in the long-term surveillance of endovascular aortic aneurysm repairs, possibly in association with CTA or MRA. Enhanced ultrasound also seems able to identify endoleaks missed by other imaging techniques, but this conclusion awaits further investigation.