Treatment of a Celiac Artery Aneurysm with a Temporary Anchoring Technique Using an Electrically Detachable Coil to Preserve the Common Hepatic and Splenic Artery Bifurcation: A Case Report

Abstract

This case report presents a unique endovascular technique using an electrically detachable coil as a temporary anchor for the treatment of a saccular celiac artery aneurysm. A man in his 60s with a 28-mm saccular aneurysm in the main trunk of the celiac artery underwent coil embolization. The short distance between the aneurysm and the bifurcation of the common hepatic and splenic arteries posed a significant challenge in preserving the bifurcation. By employing a detachable coil as a temporary anchor, the procedure enabled precise coil placement and eliminated the need for stents or balloons. Five-year outpatient follow-up imaging confirmed bifurcation patency and no aneurysm recurrence. This temporary anchoring technique can provide a practical alternative for embolization without the need for additional stents or balloons.

Introduction

Over the past few decades, treatment strategies for visceral artery aneurysms have significantly evolved, shifting from surgical intervention to endovascular treatment [1]. Preserving arterial branches during these procedures is crucial, as it greatly influences clinical outcomes and patient recovery [2]. Stent-assisted and balloon-assisted embolization techniques, established for the treatment of cerebral aneurysms, are now increasingly being applied to the abdominal region as well [3]. While these techniques effectively preserve the parent artery and ensure successful treatment, they come with additional costs due to the required use of stents and balloons [4].

Electrically detachable coils, known for their stable detachment mechanism and safe retraction, are widely used in coil embolization for visceral artery aneurysms [5]. Especially in fast-flowing and straight abdominal arteries, large metallic coils are commonly used first as permanent anchor coils during embolization. However, there have been no reports to date on the use of electrically detachable coils as temporary anchors to preserve arterial branches.

This case report presents a unique application of an electrically detachable coil used as a temporary anchor in the embolization of a celiac artery aneurysm.

Case Report

A man in his 60s was referred to our hospital for the treatment of a celiac artery aneurysm, which was incidentally found on a CT scan without any symptoms. His medical history was alcoholic liver cirrhosis and diabetes. Liver function tests showed a Child-Pugh score of 10 (Class C), indicating severe liver dysfunction. Contrast-enhanced CT demonstrated a saccular aneurysm with a maximum diameter of 28 mm in the main trunk of the celiac artery (Fig. 1A). Given the saccular morphology and size of the lesion, treatment was deemed necessary, and an endovascular approach was planned. Considering the patient's compromised liver function, priority was given to preserving the pancreaticoduodenal and dorsal pancreatic arteries. The dorsal pancreatic artery originated directly from the bifurcation of the common hepatic and splenic arteries. While the goal was to perform coil embolization with branch preservation, the short distance―approximately 12 mm―between the distal end of the aneurysm and the bifurcation of the common hepatic artery posed a significant technical challenge (Fig. 1A).

Figure 1.

(A) Contrast-enhanced CT reveals a saccular aneurysm with a maximum diameter of 28 mm in the celiac artery (arrowhead). The distal celiac artery beyond the aneurysm is short, measuring approximately 12 mm (double-headed arrow). The dorsal pancreatic artery branches from the bifurcation of the common hepatic and splenic arteries (dotted line). (B) Lateral view of the aneurysm. The celiac artery is oriented downward, and the distance to the aneurysm is relatively long. The left gastric artery originates from the aneurysm.

The proximal segment of the celiac artery was of sufficient length (Fig. 1B), and isolation was considered one of the possible treatment options. However, achieving dense embolization distal to the aneurysm was expected to be difficult, potentially resulting in incomplete treatment. A combined approach with intra-aneurysmal coil packing and isolation was planned. Balloon-assisted coil packing was initially explored as a potential strategy, but the wide-neck morphology of the aneurysm posed significant challenges to achieving successful embolization. Stent-assisted coil packing was deemed unsuitable due to a lack of insurance coverage. Another approach, using temporary balloon protection to preserve the common hepatic and splenic artery bifurcation, was also explored. A temporary balloon protection strategy via the celiac artery risked interfering with the deployed coils during catheter removal. The delivery of a balloon catheter via the pancreaticoduodenal artery was considered potentially anatomically challenging. Additionally, due to the large size of the aneurysm, the procedure was expected to require a significant number of metal coils. The additional cost of a balloon catheter presented financial constraints, necessitating the exploration of alternative solutions. To address these issues, an electrically detachable coil was employed as a temporary anchor, allowing for its reuse during the aneurysm treatment (Fig. 2).

Figure 2.

This figure illustrates the treatment strategy for this case. Utilizing flow control with a balloon catheter through one route, an electrically detachable coil is temporarily deployed as an anchor while embolization is initiated from the other route. Once the stability of the first embolization coil is confirmed, the temporary anchor coil is retrieved and reused for embolization.

The approach was made via both femoral arteries under local anesthesia. A 4.5-F guiding sheath (Parent Plus 45; Medikit Co., Ltd., Tokyo, Japan) was inserted through the right femoral artery, and a 5-F guiding sheath (Flexor Ansel; Cook Medical, Bloomington, IN, USA) through the left femoral artery. During the procedure, heparin was initially administered at a dose of 50 units per kilogram of body weight, with an additional 1,000 units given every hour. The microcatheters were continuously perfused with a solution of 5,000 units of heparin in 500 ml of saline to prevent thrombus formation. First, the origin of the celiac artery was occluded using a 5.2-F balloon catheter (Selecon MP Catheter II; Terumo Corporation, Tokyo, Japan), and contrast imaging from the SMA confirmed that blood flow to the liver and spleen was maintained via the pancreaticoduodenal and dorsal pancreatic arteries (Fig. 3A). Next, the left gastric artery branching from the aneurysm was embolized using the following metal coils: five Tornado coils (Cook Medical; 5 mm × 5 cm [3 coils], 4 mm × 4 cm [2 coils]) and three 0.014-inch C-Stopper coils (Piolax Medical Devices, Yokohama, Japan; 100 mm [3 coils]) (Fig. 3B). Two guiding sheaths were positioned in the celiac artery. A balloon catheter (Selecon MP Catheter II) was introduced through a 5-F guiding sheath (Flexor Ansel) and inflated at the origin of the celiac artery to control blood flow. A temporary anchor coil (Target XXL 360 standard; Stryker Neurovascular, Fremont, CA, USA; 10 mm × 40 cm [1 coil]) was placed at the bifurcation of the common hepatic and splenic arteries without detachment, using a 2.3-F microcatheter (Carry 2Marker microcatheter; UTM Co., Ltd., Toyohashi, Japan) coaxially introduced via the Selecon MP Catheter II (Fig. 3C). A 2.9-F microcatheter (Leonis Mova High Flow; Sumitomo Bakelite, Tokyo, Japan) was coaxially introduced via a 4-F RH catheter (Hanako Medical, Saitama, Japan) and a 4.5-F guiding sheath (Parent Plus 45). The Leonis Mova High Flow was advanced into the distal celiac artery beyond the aneurysm, and an electrically detachable coil (Target XL 360 soft; Stryker Neurovascular; 10 mm × 40 cm) was placed as the first coil using this catheter (Fig. 3D). After confirming the stability of the first coil, the temporary anchor coil was carefully removed (Fig. 3E), and embolization of the aneurysm was continued. The aneurysm was packed with the following types of metal coils during the procedure: Ruby coil (Penumbra, Alameda, CA, USA; 20 mm × 60 cm [3 coils], 18 mm × 57 cm [1 coil]), POD packing coil (Penumbra; 60 cm [5 coils], 45 cm [4 coils], 30 cm [1 coil]), Target XXL 360 standard (10 mm × 40 cm [1 coil], 8 mm × 30 cm [2 coils]), Target XL 360 soft (10 mm × 25 cm [1 coil]), and CERENOVUS MICRUS FRAME C coil (Johnson & Johnson MedTech, Irvine, CA, USA; 10 mm × 25 cm [1 coil], 6 mm × 15 cm [1 coil]). The temporary anchor coil (Target XXL 360 standard; 10 mm × 40 cm [1 coil]) was reused for packing the aneurysm. Some detachable coils unintentionally migrated into the left gastric artery during aneurysm packing. The microcatheter used for the temporary anchor coil was left in the common hepatic artery as a precaution against unintended coil migration and was removed after completing the embolization procedure (Fig. 3F). Final imaging of the SMA confirmed that blood flow to the common hepatic and splenic arteries was preserved, and the aneurysm was no longer visible (Fig. 3G). The procedure was successfully completed without any complications. The postoperative course was uneventful, allowing the patient to be discharged on the sixth day. The patient has since been under outpatient follow-up for 5 years post-surgery, without evidence of coil compaction or aneurysm reperfusion on follow-up imaging, and has not required any additional treatment.

Figure 3.

(A) With the celiac artery occluded using a balloon catheter, contrast imaging from the SMA shows maintained blood flow to the liver and spleen via the pancreaticoduodenal and dorsal pancreatic arteries. (B) Coil embolization is performed on the left gastric artery originating from the aneurysm. (C) A temporary anchor coil is placed at the bifurcation of the common hepatic and splenic arteries under flow control using a balloon catheter. (D) The undetached coil (white arrow) serves as a temporary anchor to position the first embolization coil (black arrow) in the distal part of the celiac artery. (E) A temporary anchor coil is carefully removed. (F) During coil embolization, the microcatheter used for placing a temporary anchor coil is kept in the common hepatic artery until embolization is completed to address any unforeseen events, such as coil migration. Some detachable coils unintentionally migrated into the left gastric artery during aneurysm packing. (G) Final angiography from the SMA confirms intact blood flow to the hepatic and splenic arteries, with the aneurysm no longer visible.

Discussion

Celiac artery aneurysms account for 4% of visceral artery aneurysms, making them the fourth most common type [6]. According to the Journal of Vascular Surgery guidelines, treatment is recommended when celiac artery aneurysms reach 2 cm in size or when they are pseudoaneurysms [1]. In this case, the aneurysm measured 28 mm and had a saccular shape, necessitating treatment. The treatment of visceral artery aneurysms, such as those in the spleen and kidneys, has increasingly shifted from surgical to endovascular methods due to their minimally invasive nature. However, in the celiac artery region, achieving sufficient space for coil embolization on both the proximal and distal sides is particularly challenging due to the presence of significant branches, such as the common hepatic artery and the splenic artery. Reports of successful endovascular treatment alone for celiac artery aneurysms are less common compared to other locations [7].

There have been no prior reports of using electrically detachable coils as temporary anchors for treating aneurysms while preserving critical branches. In this case, the short distance to the splenic-common hepatic artery bifurcation posed challenges for branch preservation using conventional embolization techniques. While stent grafts have been reported as a treatment option for visceral artery aneurysms, their use was not feasible in this case due to the absence of insurance coverage and the technical limitations at the time, which required a sheath larger than 10-Fr [8]. Although the coil-in-plug method is now a viable option for anchor formation, it was not yet published at the time of treatment [9].

The temporary anchoring technique, although requiring an additional microcatheter, provided a simpler and more flexible alternative without the need for balloon manipulation. The need for dual access was a disadvantage, but it was comparable to the invasiveness of balloon- or stent-assisted embolization techniques. A previous report on trans-arterial radioembolization for liver cancer described the temporary placement of detachable coils in the cystic artery to prevent drug leakage, followed by their removal after drug administration [10]. The report noted no complications or drug leakage into the cystic artery. According to this report, only one type of detachable coil was available in Korea at the time of the study, and a mechanically detachable coil (Interlock; Boston Scientific, Marlborough, MA, USA) was used. For the temporary anchor coil, an XXL 360 standard coil from Stryker's Target series was used in the current case. The reasons for this choice include the coil's safe electrical detachment mechanism, lack of fiber or gel that could cause complications during retrieval, and its suitability as a bare coil. The XXL 360 standard coils, with a primary coil diameter of 0.017 inches, served as ideal anchors. Although wire- and mechanically detachable coils are more cost-effective, electrically detachable coils were preferred due to their safer and more reliable detachment mechanism. The anchor coil demonstrated excellent stability, with no premature detachment or unraveling. It was carefully and smoothly retrieved under fluoroscopic guidance. Given the common hepatic artery diameter of approximately 6 mm, an anchor coil with 180% oversizing was selected. However, the large coil loops prolonged the time required to achieve a stable anchoring configuration. As the distal portion of the aneurysm measured 7-8 mm, a softer coil (Target XL Soft) with 120%-150% sizing was selected as the first coil to prevent protrusion into the bifurcation. The timing for removing the temporary anchor coil was set immediately after placing the first coil to minimize interference. Delaying the removal of the anchor coil too long raised concerns about potential complications, such as migration or unraveling due to coil interference. The procedure was seamlessly completed by removing the temporary anchor coil following the placement of the first coil. Flow control by inflating a balloon in the celiac artery reversed the blood flow, which helped stabilize coil placement and prevent coil migration to the common hepatic-splenic artery bifurcation. Heparinization and continuous perfusion within the catheter were performed during the operation to prevent complications associated with thrombus formation. Additionally, even after removing the temporary anchor coil, the microcatheter was not immediately withdrawn. If the coil migrated to overlap the common hepatic-splenic artery bifurcation, the plan was to insert a wire and use a balloon catheter to retrieve the displaced coil back into the aneurysm. These precautionary measures were taken to address any potential coil migration, which was considered a key factor in the safe and successful completion of this procedure.

The limitations of this technique include the need for dual vascular access, the potential for coil interference or related complications, and the lower anchoring reliability of the coil compared to a balloon catheter in preventing migration. Although aneurysm isolation would have been more cost-effective, the concomitant use of coil packing diminished this advantage, representing an additional limitation.

This case demonstrates that an electrically detachable coil can be used as a temporary anchor to successfully embolize a celiac artery aneurysm while preserving the bifurcation of the common hepatic and splenic arteries without the need for balloons or stents. This technique offers a practical and device-sparing alternative for embolization.

Conflict of Interest

None

Author Contribution

KS was mainly involved in drafting the manuscript and creating the figures. MY was involved in the intervention of the case and in drafting the manuscript. AU, TY, and TG were involved in drafting the manuscript. MY, EU, and TM critically revised the entire manuscript. All authors reviewed the manuscript.

Informed Consent

Informed consent was obtained from the patient to submit this case report.

Disclaimer

Dr. Masato Yamaguchi, an author of this paper and a member of the Editorial Board of this journal, was not involved in the peer-review or editorial decision-making process.