Strategy of stretched Coils: Insights from a single center experience

A stretched coil, characterized by excessive elongation within the parent artery during a coil embolization procedure, poses a significant risk of forming a thrombus. This study reports on cases of stretched coils spanning 16 years and discusses effective assessment methods and treatment strategies.

Retrospective analysis of the institutional database comprising 14 cases where stretched coils were observed during coil embolization procedures was conducted, starting from January 2007.

Among the 14 cases, four involved coil embolization for subarachnoid hemorrhage due to ruptured aneurysm, while the remaining cases were unruptured aneurysms. Starting in 2017, vaso-computed tomography (vaso-CT) was employed in nine cases to evaluate the proximal end of the stretched coils. Reimplantation was performed in 3 cases. Among them, two cases were relieved by pushing the coil delivery wire or microwire, while one case underwent balloon-assisted reimplantation. The stretched coils were removed in three cases by pulling. A rescue gooseneck microsnare technique was applied in one case. The stent was fixed in five cases. In two cases, no additional procedures were performed. Thrombosis is a potential complication that occurred in three cases of stretched coils.

Many studies have addressed coil stretching and introduced various rescue methods, but relying solely on angiography for diagnosis or applying an inappropriate rescue technique can lead to ischemic stroke. This study emphasized the importance of vaso-CT as a tool for accurately identifying the proximal end of a stretched coil. Additionally, we aimed to facilitate the selection of an appropriate rescue technique.