Diagnosis and management of endoleaks after endovascular aneurysm repair: role of MRI

Embolization of Type 2 Endoleaks in the Abdominal Aorta Using Ethylene Vinyl Alcohol Copolymer

BACKGROUND

 Type 2 endoleaks (T2EL) are the most frequent complication following endovascular aortic repair. Multiple studies primarily deal with the technical and clinical success of the embolization of persisting T2EL, thereby revealing controversial outcomes. Current reports rarely focus on the detailed execution of such a complex interventional procedure with respect to the difficult anatomic setting.

METHODS

 The present review provides an in-depth depiction and evaluation of the interventional methodology of the embolization of T2EL in the abdominal aorta with use of ethylene vinyl alcohol copolymer (EVOH). Complicating anatomic conditions are taken into account as well as technical and clinical success rates.

RESULTS

 Using the transarterial approach, there are at least 4 different pathways to access the nidus of a T2EL. CT-guided direct puncture of the aneurysm sac provides an alternative method of high technical success. EVOH with its slow solidification characteristics enables good control to achieve complete filling of the T2EL. During the intervention, however, it remains difficult to meet exactly the embolization endpoint, especially in large T2ELs.

CONCLUSION

 T2EL embolization using EVOH is an effective treatment with low major complication rates when conducted by skilled interventionists with detailed knowledge of diverse complex access routes.

KEY POINTS

  · Many roads lead to Rome to access the nidus of a T2EL including diverse complex transarterial pathways and direct aneurysm sac puncture.. · Ethylene vinyl alcohol co-polymer enables good control for slow filling of the nidus with low risk of major complications.. · Identification of the embolization endpoint remains difficult during the procedure and may result in secondary interventions.. · Successful T2EL embolization requires detailed knowledge of all access routes to the nidus and skilled handling of liquid embolics..

CITATION FORMAT

· Nolte-Ernsting C, Mecklenbeck F, Stehr A. Embolization of Type 2 Endoleaks in the Abdominal Aorta Using Ethylene Vinyl Alcohol Copolymer. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1502-7883.

Prospective, intraindividual comparison of MRI versus MDCT for endoleak detection after endovascular repair of abdominal aortic aneurysms

This study compares MRI and MDCT for endoleak detection after endovascular repair of abdominal aortic aneurysms (EVAR). Forty-three patients with previous EVAR underwent both MRI (2D T1-FFE unenhanced and contrast-enhanced; 3D triphasic contrast-enhanced) and 16-slice MDCT (unenhanced and biphasic contrast-enhanced) within 1 week of each other for endoleak detection. MRI was performed by using a high-relaxivity contrast medium (gadobenate dimeglumine, MultiHance). Two blinded, independent observers evaluated MRI and MDCT separately. Consensus reading of MRI and MDCT studies was defined as reference standard. Sensitivity, specificity, and accuracy were calculated and Cohen's k statistics were used to estimate agreement between readers. Twenty endoleaks were detected in 18 patients at consensus reading (12 type II and 8 indeterminate endoleaks). Sensitivity, specificity, and accuracy for endoleak detection were 100%, 92%, and 96%, respectively, for reader 1 (95%, 81%, 87% for reader 2) for MRI and 55%, 100%, and 80% for reader 1 (60%, 100%, 82% for reader 2) for MDCT. Interobserver agreement was excellent for MDCT (k = 0.96) and good for MRI (k = 0.81). MRI with the use of a high-relaxivity contrast agent is significantly superior in the detection of endoleaks after EVAR compared with MDCT. MRI may therefore become the preferred technique for patient follow-up after EVAR.

Endoleak detection and classification after endovascular treatment of abdominal aortic aneurysm: value of CEUS over CTA

This paper focuses on the diagnostic value of CEUS in the detection and characterization of endoleaks in comparison with other imaging modalities, primary CDUS and CTA in the follow-up of endovascular abdominal aortic aneurysm repair. CEUS is an interesting alternative technique because of its limited costs and lack of exposure to ionizing radiation. However, CTA cannot currently be substituted because it enables a more precise evaluation of aneurysm morphologic changes, aneurysm sac diameter, graft anchorage and integrity. CEUS could be used along with CTA when the latter reveals the presence of endoleak, to provide a better characterization of it taking advantage of the angiodynamic behavior of the contrast agent that permits an easier visualization of the agent flow into the sac. It could also be indicated when aneurysm diameter increases and CTA did not show sac reperfusion or to monitor type II endoleaks reducing the use of CTA with consequent reduction of costs and exposure to radiation.