Retrieval of unintended migrated detached coil: case report

A Unique Technique to Adjust Snare Position for Coil Retrieval in Tortuous Vessel During Aneurysm Coil Embolization: A Technical Case Report

OBJECTIVE

Although snares are useful devices to retrieve an intravascular foreign body, the control of snares is often difficult. We present a safe and effective technique to adjust snare position in the tortuous vessel for coil retrieval during endovascular coil embolization.

METHODS

We describe a case of a protruding coil during coil embolization that was successfully retrieved using a unique technique to adjust snare position and discuss additional intraprocedural bailout strategies for retrieving a coil during endovascular coil embolization.

RESULTS

The patient was a 44-year-old female with unruptured right internal carotid artery (ICA) aneurysm that had grown over a 1.5-year period. Coil embolization was performed. After detachment of final coil and microcatheter removal, the final coil protruded into the ICA and floated. Coil retrieval using a snare was attempted, but the snare could not be placed around the coil tail and coil retrieval could not be achieved. The following technique was used to allow adjustment of snare position. First, a microguidewire and a microcatheter were guided into the M2 and M1 segment of the middle cerebral artery as monorail guides of the snare, respectively. Next, the snare was advanced over the microcatheter. Around C2 segment of the ICA, the microcatheter and the snare were manipulated as a unit. Thus, the snare could be placed around the protruding coil tail and the coil was retrieved successfully.

CONCLUSIONS

This technique may be widely adapted for various situations when using a snare.

Magnetic wires: A novel design for neuroendovascular coil retrieval

The present study aimed to evaluate the operation, application and safety of a novel prototype device designed for the retrieval of a migrated coils, an intraprocedural complication of endovascular aneurysm treatment, compared with the widely used Solitaire AB stent retriever. The prototype retrieval device, referred to as magnetic wires, consisted of two microwires that were joined by a small magnetic ring near to the tips. To retrieve a coil, the wires are advanced through the dislodged coil one at a time and then capture the target coil in a chopstick-like manner, as their tips are attracted to the magnet. In vitro tests were performed five times for each retrieval device using a pulsing flow circulator to compare retrieval effectiveness. In vivo efficacy testing was performed in 5 male piglets. The left and right carotid arteries were used to assess the magnetic wires and the Solitaire retriever, respectively. While the two devices successfully retrieved coils in vitro at a rate of 100%, the magnetic wires did so in a shorter time. In vivo, the magnetic wires successfully captured the migrated coils in 3/5 cases (60%), whereas the Solitaire AB stent retriever was successful 4/5 cases (80%). Endothelial injury was observed following magnetic wires retrieval in 1/5 cases (20%) and following use of the Solitaire AB stent retriever in 3/5 cases (60%). These results demonstrate the feasibility and safety of this novel prototype coil retrieval device, which with further development has the potential to be an optimal device for the retrieval of dislodged coils.

Retrieval of Distally Migrated Coils with Detachable Intracranial Stent during Coil Embolization of Cerebral Aneurysm

Migration of coils during endovascular procedures is a rare, but well-known complication. We are reporting two cases of successfully retrieving migrated coil using detachable intracranial stent. In both of our cases there was distal migration of coil during the intracranial aneurysm coiling procedure. The Solitaire® AB stent (Covidien, Irvine, CA, USA) was used to retrieve those coils. The stent was passed distal to the migrated coil using standard technique. It was then partially deployed and gradually withdrawn along with the entangled coil. Coil retrieval using the fully retrievable intracranial stent is a very simple, safe and easily available alternative for retrieval of distally migrated coil.