Rescue Retrieval of a Fully Deployed Low-Profile Intracranial Stent After Acute Occlusion

Microsnare Retrieval of a Distorted Flow Re-direction Endoluminal Device (FRED)

Retained endovascular devices are becoming increasingly reported as the indications for endovascular intervention continue to expand. As such, an interventionalist needs to be prepared to extract devices that are improperly deployed. This case illustrates the successful retrieval of an incompletely opened flow diverting stent using a microsnare. This is the second reported case of this complication and the first known case specific to the flow re-direction endoluminal device (FRED; Microvention, Aliso Viejo, California, USA).

Bailout stentectomy of 47 self-expandable intracranial stents

Background

Self-expanding stents are increasingly being deployed for stent-assisted coiling or flow diversion of intracranial aneurysms. Complications related to stent misbehavior may arise, however, including lack of expansion, device displacement, or parent vessel thrombosis. We present our experience of various stent removal techniques (stentectomy) with a focus on technical and clinical outcomes.

Methods

Stentectomy was attempted either with a single device, including the Alligator, Microsnare, or Solitaire, or by combining a Microsnare with a second device. Dual techniques included in this report are the Snare-over-Stentretriever technique we developed using a Microsnare and a Solitaire, and the previously described Loop-and-Snare technique using a Microsnare and a microwire. The technical success and complication rate, as well as the clinical outcome using the mRS were analyzed.

Results

Forty-seven stentectomies were attempted in 36 patients treated for 37 aneurysms. Forty-two devices (89.3%) were successfully retrieved. Single-device stentectomy was successful in 34% of cases, compared with 74% with dual-device techniques. Of the 20 patients with a thrombosed parent or efferent vessel, 17 were successfully recanalized using stentectomy. All successful stentectomy patients made a clinically uneventful recovery, except one with a minor postoperative stroke (mRS 1 at discharge). Failed stentectomy was associated with major ischemic stroke in two patients and death in one patient. There were no stentectomy-related vessel perforations or dissections.

Conclusion

While various single devices can be used to safely retrieve dysfunctional intracranial self-expandable stents, dual-device techniques are more than twice as effective, according to our experience.

Solitaire Stentectomy Using a Stent-Retriever Technique in a Porcine Model

PURPOSE

Mechanical thrombectomy using the Solitaire device has become a standard treatment of ischemic stroke due to large vessel occlusions. Inadvertent detachment is a feared complication, which is associated with poor clinical outcome. The aim of this experimental study was to assess in a porcine model the feasibility and effectiveness of rescuing detached Solitaire devices using different stent retrievers.

METHODS

Solitaire FR devices (4 × 15/20 mm and 6 × 20/30 mm) were placed in the axillary artery of pigs. By means of 3 different stent retrievers (Trevo ProVue; EmboTrap II revascularization device; 3D revascularization device) a total of 24 rescue maneuvers (8 per retriever) were performed by deploying the retrievers within the deployed Solitaire devices and trapping parts of the Solitaire within the microcatheter. Rescue rates, rescue time and complications were assessed.

RESULTS

Overall stentectomy of the Solitaire devices was successful in all cases (100%). Time of rescue was comparable using the applied stent retrievers (Trevo ProVue; EmboTrap II revascularization device; 3D revascularization device). Complications, such as entrapment of the Solitaire-retriever complex at the intermediate catheter, Solitaire migration, vasospasm, perforation, or dissection were not observed.

CONCLUSION

Stentectomy of inadvertently detached Solitaire devices using different stent retrievers is a feasible and effective method. Rescue rates and times with the Trevo ProVue, EmboTrap II and 3D revascularization device were comparable.

Rescue of migrated Woven Endobridge devices using a stent-retriever-technique in a porcine model

PURPOSE

The Woven Endobridge device (WEB) has become widely applied for the treatment of intracranial aneurysms. Complications are rare, however, especially dislocations and migrations can potentially increase poor clinical outcome. The aim of this study was to assess the feasibility and effectiveness of rescuing migrated Woven Endobridges using different stent retrievers.

METHODS

In a porcine model, Woven Endobridges of different sizes (SLS 4, SLS 7, SL 5 × 3, SL 4 × 3) were placed into the axillary arteries. By means of two different stent retrievers (Solitaire Platinum and 3D Revascularization Device), a total of 20 rescue maneuvers were performed. For this purpose, the retrievers were deployed distally of the migrated Woven Endobridges. After retracting the stent retrievers partially, the Woven Endobridges were trapped within the microcatheter. Rescue rates, time, attempts and complications were assessed.

RESULTS

Successful rescue of the migrated Woven Endobridges was observed in all cases (100%). Rescue was slightly faster (177.8 ± 72.8 s vs. 223.4 ± 104.1 s) with fewer attempts (1.5 ± 0.8 vs. 1.8 ± 0.9) when using the 3D Revascularization Device compared to the Solitaire Platinum. However, there were no significant differences (p = 0.327; p = 0.554). Migration of the Woven Endobridges during rescue was seen with both stent retrievers in a comparable frequency (p = 0.642). Further complications, such as entrapment of the stent-retriever-WovenEndobridge-complex at the intermediate catheter, vasospasm, perforation or dissection, were not observed.

CONCLUSIONS

Rescue of migrated Woven Endobridges using stent retrievers is a feasible and effective method. Rescue rates, times and attempts with the Solitaire Platinum and 3D Revascularization Device are comparable with each other.

A case of anterior communicating artery aneurysm successfully treated after a stent migration during stent assisted endovascular coil embolization

Stent migration is a complication associated with endovascular coil embolization of intracranial aneurysms. We report a case of anterior communicating artery (ACoA) aneurysm that was successfully treated after stent migration during endovascular coil embolization without retrieval of the stent. A 47-year-old man presented with sudden onset severe headache. Patient was noted to have subarachnoid hemorrhage from a ruptured ACoA aneurysm. Emergency endovascular coil embolization was performed. The second coil embolization was scheduled for the neck-remnant portion with a stent after 16 days from the initial operation. At first, a stent was deployed from the right perpendicular division of anterior cerebral artery (A2) to the left horizontal division of anterior cerebral artery (A1) entirely across the aneurysmal neck. Although the stent position looked fine, the stent migrated inferiorly to the proximal A1 portion when its delivery wire was withdrawn. Fortunately, the stent could be pushed into the distal A1 portion, when we trying to re-access the aneurysm thorough the stent with a pig-tail shaped microguidewire. Additional coil embolization was achieved using the assistance of distal tip of the stent as a scaffold of the coil. The patient was discharged without any complication on the postoperative day 6. Although there are various choices of rescue treatment after stent migration, this is the first reported case of stent repositioning with a microguidewire. Our technique may represent an effective option in case of stent migration.

Endovascular stentectomy using the snare over stent-retriever (SOS) technique: An experimental feasibility study

Feasibility of endovascular stentectomy using a snare over stent-retriever (SOS) technique was evaluated in a silicon flow model and an in vivo swine model. In vitro, stentectomy of different intracranial stents using the SOS technique was feasible in 22 out of 24 (92%) retrieval maneuvers. In vivo, stentectomy was successful in 10 out of 10 procedures (100%). In one case self-limiting vasospasm was observed angiographically as a technique related complication in the animal model. Endovascular stentectomy using the SOS technique is feasible in an experimental setting and may be transferred to a clinical scenario.