RESUMO
Ultrasound (US) represents the initial modality in the workup of abdominal aortic pathology based on the plethora of advantages including widespread availability, low cost, safety profile and repeatability. However, US has inherent limitations including limited spatial information of pathologic processes to neighboring structures, lower sensitivity to slow blood flow and aortic luminal irregularities. For evaluation of aortic pathology angiography has long been considered the gold standard. Non-invasive cross-sectional imaging techniques like computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have gradually replaced interventional angiography for the evaluation of aorta, currently being regarded as the diagnostic imaging modalities of choice for diagnosis of virtually every aortic disease. Interventional angiography is currently primarily performed for treatment purposes of aortic pathology. The introduction of microbubbles as ultrasonographic contrast agents has rendered contrast-enhanced ultrasound (CEUS) an evolving valuable complementary technique with markedly increased diagnostic accuracy for certain aortic applications. CEUS is characterized by the potential to be performed in patients with impaired renal function. Due to its superior spatial and temporal resolution, ability for prolonged scanning and dynamic and real-time imaging, it provides clinically significant additional information compared to the standard Duplex US. The purpose of this paper is to discuss the currently available literature regarding abdominal aortic applications of CEUS, briefly elaborate on CEUS technique and safety and present cases in order to illustrate the added value in aortic pathologies. Conditions discussed include abdominal aortic aneurysm (AAA), aneurysm rupture, aneurysm surveillance after endovascular repair, dissection and aortitis.
RESUMO
Background Inflammatory processes of the venous wall in acute deep vein thrombosis (DVT) play a role in thrombus formation and resolution. However, direct evaluation of the perivascular inflammation is currently not feasible. Objective To assess perivascular perfusion in acute proximal DVT using contrast-enhanced ultrasound (CEUS) reflecting perivenous inflammation and its association with systemic inflammatory markers in a single-centre, prospective observational study. Patients/Methods Twenty patients with proximal DVT underwent CEUS imaging in the thrombosed and contralateral popliteal vein at baseline and after 2 weeks and 3 months. Perfusion was quantified by measuring peak enhancement (PE) and wash-in rate (WiR) in a perivenous region after bolus injection of the contrast agent. High-sensitive C-reactive protein (hsCRP) and interleukin-6 (IL-6) were determined at the time of each CEUS imaging. Results PE and WiR were significantly higher in the thrombosed compared with the unaffected leg at baseline (1,007 vs. 34 au and 103 vs. 4 au/s) and 2-week follow-up (903 vs. 35 au and 70 vs. 4 au/s). Compared with baseline, PE and WiR in the thrombosed leg significantly decreased to 217 au and 18 au/s at 3-month follow-up.At baseline, hsCRP and IL-6 were elevated at 20.1 mg/mL and 8.2 pg/mL and decreased significantly to 2.8 mg/mL and 2.6 pg/mL at 2-week follow-up, remaining low after 3 months. There was a weak association between the level of inflammatory markers and the CEUS parameters at baseline on the thrombosed leg. Conclusion Elevated perivascular perfusion assessed by CEUS imaging is associated with the inflammatory response in acute DVT.