Introduction

The embolization of iliac and abdominal aneurysms can often be very challenging. Because of the large aneurysmal volumes that often accompany these aneurysms, wide-diameter, highly thrombogenic devices are often required to obtain stasis. Additionally, navigation of catheters and wires to these aneurysms, particularly when embolizing type II endoleaks, often requires the clinician to traverse through challenging anatomy with smaller, more precise embolization devices. With these conflicting priorities, very few embolization platforms satisfy the need for precise delivery and high thrombogenicity.

One of the most important advances that has assisted physicians in the embolization of these challenging anomalies is the development of long, fibered detachable coils. These devices have allowed for the delivery of large volumes of embolic materials quickly and accurately. As a result, many of the procedures that have traditionally been very time consuming and challenging have become common practice for experienced interventionalists.

The following case demonstrated the utility of the Interlock™ Fibered IDC™ Occlusion System in a patient suffering from a massive iliac aneurysm.

Iliac Vein Aneurysm

A 47-year-old man was imaged using CT, which revealed a large, 7-cm X 14-cm iliac vein aneurysm on the left side.

Due to the size of the aneurysm, collateral vessel embolization with fibered platinum coils was attempted. The aneurysm was accessed, and coil embolization of the three collateral vessels filling the aneurysm sac was attempted. Because of the need to precisely select the collateral vessels inside the aneurysm sac, an angled Renegade® STC Microcatheter and Fathom® Guidewire were selected, so that control of the wire and the tip of the catheter could be maintained. Following catheter placement, eight 14-mm X 30-cm .018-inch Interlock™ Fibered Coils were placed into the three collateral vessels (Figure 1).

After 3 to 4 minutes, the embolized vessels were completely shut down. However, numerous additional collateral vessels were observed filling the sac. Due to the number of collaterals observed and the magnitude of the aneurysm, we determined that complete embolization of the aneurysm would provide the patient with the greatest chance for long-term success. We opted to remove our microcatheter-based system and embolize the aneurysm using a 5-F catheter and the Interlock™ – 35 Fibered Coils. We did this by using a 6-F sheath and a 5-F, 100-cm Bern-shaped catheter to re-access the aneurysm sac.

Due to the number of coils anticipated for completion, special care was taken to hook up a bag of continuous flush to the Bern-shaped catheter before placing coils. We placed the catheter at the distal portion of the aneurysm and began working our way proximally, with 20-mm X 40-cm and 18-mm X 40-cm Interlock™ – 35 Coils.

A total of thirty 20-mm X 40-cm coils and eight 18-mm X 40-cm coils were placed (Figure 2). We utilized both 20-mm X 40-cm Cube-shaped coils and 18-mm X 40-cm 2D Helical-shaped coils in an attempt to make the coil nest as tight as possible by alternating shapes. We achieved a very tight pack, and there was absolutely no flow going into the aneurysm sac (Figure 3).

Discussion

Although the initial objective of the procedure was simply to embolize the collateral vessels of the aneurysm, the presence of multiple new collateral vessels appearing post-embolization caused us to alter our approach. Due to the enormous size of this iliac vein aneurysm, a total of more than 1,700 centimeters of coil was introduced into the patient in a very rapid and efficient manner. The presence of 40-cm-long coils assisted greatly in the speed of the procedure.

Timothy Riley, MD, is a Vascular Surgeon at St. Joseph's Hospital Health Center in Syracuse, New York.