Coil Embolization of Splenic Artery Aneurysm with Preservation of the Parent Artery Using a Neck Remodeling Technique

Combination of the double-microcatheter technique and triaxial system in coil packing for visceral and renal artery aneurysms

Background

In coil packing for visceral artery aneurysms (VAAs), difficulties are sometimes associated with preserving the patency of the parent artery, particularly for wide-neck aneurysms. However, the double-microcatheter technique effectively prevents coil migration, while the triple-coaxial (triaxial) system is useful for reducing microcatheter kick-back.

Purpose

To assess the feasibility of combining these two techniques in coil packing for VAAs.

Material and Methods

Coil packing using the double-microcatheter technique and triaxial system was attempted for seven VAAs in six patients between August 2015 and January 2018. The technical success rate, packing density of aneurysms, complications related to the procedure, and occlusion status were evaluated. Technical success was defined as the completion of coil packing by immediate post-embolic angiography. The occlusion status was evaluated using time-resolved magnetic resonance angiography.

Results

There were three renal, three splenic, and one anterior superior pancreaticoduodenal aneurysms. The median size of VAAs was 13 mm (range = 8–21 mm), with five being classified as wide-neck aneurysms. The completion of coil packing was confirmed for all VAAs and the technical success rate was 100%. The median packing density was 28% (range = 22–40%). There were no complications related to the procedure. The median follow-up period was 14 months (range = 8–24 months). In six VAAs that were followed up, there were three complete occlusions, three neck remnants, and no body filling; re-treatment was not required in any patient.

Conclusion

The combination of the double-microcatheter technique and triaxial system is a feasible method of coil packing for VAAs.

Management of visceral artery embolization using 0.010-inch detachable microcoils

Transcatheter coil embolization is used primarily to treat arterial hemorrhages, tumors, aneurysms, and vascular malformations. However, conventional microcatheter systems cannot always be employed in difficult cases. In this technical note, we describe how small-diameter primary coils and microcatheter tips that are thinner than normal can be used to increase the safety and reliability of coil embolization.

Follow-up of true visceral artery aneurysm after coil embolization by three-dimensional contrast-enhanced MR angiography

PURPOSE

We aimed to evaluate the outcomes of coil embolization of true visceral artery aneurysms by three-dimensional contrast-enhanced magnetic resonance (MR) angiography.

MATERIALS AND METHODS

We used three-dimensional contrast-enhanced MR angiography, which included source images, to evaluate 23 patients (mean age, 60 years; range, 28-83 years) with true visceral artery aneurysms (splenic, n=15; hepatic, n=2; gastroduodenal, n=2; celiac, n=2; pancreaticoduodenal, n=1; gastroepiploic, n=1) who underwent coil embolization. Angiographic aneurysmal occlusion was revealed in all cases. Follow-up MR angiography was conducted with either a 1.5 or 3 Tesla system 3-25 months (mean, 18 months) after embolization. MR angiography was evaluated for aneurysmal occlusion, hemodynamic status, and complications.

RESULTS

Complete aneurysmal occlusion was determined in 22 patients (96%) on follow-up MR angiography (mean follow-up period, 18 months). Neck recanalization, which was observed at nine and 20 months after embolization, was confirmed in one of eight patients (13%) using a neck preservation technique. In this patient, a small neck recanalization covered by a coil mass was demonstrated. The complete hemodynamic status after embolization was determined in 21 patients (91%); the visualization of several collateral vessels, such as short gastric arteries, after parent artery occlusion was poor compared with that seen on digital subtraction angiography in the remaining two patients (9%). An asymptomatic localized splenic infarction was confirmed in one patient (4%).

CONCLUSION

Our study presents the follow-up results from three-dimensional contrast-enhanced MR angiography, which confirmed neck recanalization, the approximate hemodynamic status, and complications. This effective and less invasive method may be suitable for serial follow-up after coil embolization of true visceral aneurysms.

Long-term outcomes of coil packing for visceral aneurysms: correlation between packing density and incidence of coil compaction or recanalization

PURPOSE

To evaluate the correlation between packing density and the incidence of coil compaction or recanalization of visceral artery aneurysms (VAAs) after coil packing.

MATERIALS AND METHODS

Between July 2004 and April 2012, coil packing was performed for 46 true visceral aneurysms (16 splenic, 11 pancreaticoduodenal, eight renal, six hepatic, three superior mesenteric, one right gastric, and one gastroepiploic) in 42 patients. The size and volume of the aneurysm, packing density, and the incidences of compaction and recanalization were evaluated retrospectively.

RESULTS

The mean follow-up period was 37 months ± 8 (range, 11-80 mo). The mean packing density was 19% ± 8 (range, 5%-42%), mean aneurysm size was 19 mm ± 8 (range, 5-40 mm), and mean volume was 4,108 mm(3) ± 5,435 (range, 72-26,235 mm(3)). Compaction and recanalization occurred in two (4%) and 12 aneurysms (26%), respectively. The mean packing density was significantly lower in aneurysms with compaction or recanalization than in unaffected aneurysms (12% vs 22%; P = .00014). There was a significant difference in mean packing density between small (< 20 mm; 22%) and large (≥ 20 mm) aneurysms (15%; P = .0045). The mean size and volume were significantly larger for coil-compacted or recanalized aneurysms than for unaffected aneurysms (P < .05). In aneurysms with a packing density of at least 24%, no compaction or recanalization occurred.

CONCLUSIONS

Coil compaction or recanalization after coil packing for VAAs more often occurs after insufficient embolization with low packing density and in patients with large aneurysms.

Giant splenic artery aneurysm: managed in the cardiovascular catheterization laboratory using the modified neck remodeling technique

We report the first case of coil embolization using the "modified neck remodeling technique" in the management of a splenic artery aneurysm. This technique was feasible due to the unique and complex anatomy of the aneurysm. This condition has been largely treated by vascular surgeons and interventional radiologists; however, this patient was referred to the interventional cardiologists for endovascular coiling.