We describe a case of coil unraveling that occurred during stent-assisted cerebral aneurysm embolization. The unraveled coil was stretched and the loose end was fixed in the external carotid artery by the addition of other coils. Herniation of the loose coil end to the distal part of the vessel with potential vessel occlusion was prevented and no immediate or long-term complication was observed. © 2010 Wiley-Liss, Inc.