Retrieval of Migrated Volume Coils Using Different Clot Retrievers in a Porcine Model

During endovascular treatment of intracranial aneurysms using coils, migration is a serious complication that increases neurological morbidity. The aim of this experimental study was to assess the effectiveness and complications of retrieving volume coils with different, currently available clot retrievers in a porcine model.

Volume coils of three-dimensional (3D) shape and different sizes were placed in the axillary artery of pigs. By means of 4 different clot retrievers (Trevo ProVue; Solitaire FR; 3D-Separator; ERIC) a total of 40 retrieval maneuvers (10 per retriever) were performed by deploying the retrievers within the migrated coils and trying to trap parts of the coils by advancing the microcatheter. Retrieval rates, retrieval duration, retrieval attempts, and complications were assessed.

Overall coil retrieval was successful in 31 of 40 cases (77.5%). Retrieval rates using the Trevo ProVue (9/10), Solitaire FR (8/10), and the 3D-Separator (9/10) were higher than when using the ERIC (5/10). Duration of retrieval and retrieval attempts were significantly higher using the ERIC (p < 0.05). Complications like inadvertent deployment were only observed in one case using the Solitaire FR. Additional entrapment of the coil-retriever complex at the intermediate catheter was seen in 9 cases (22.5%). There was no case of vasospasm, perforation, or dissection.

Retrieval of migrated volume coils using new-generation clot retrievers is a feasible and effective method. Retrieval rates and duration with the Trevo ProVue, Solitaire FR, and 3D-Separator are superior when compared to the ERIC.