US Patent 7485122 Integrated anchor coil in stretch-resistant vaso-occlusive coils

Vaso-occlusive devices are provided for occluding an aneurysm within the human vasculature. The vaso-occlusive device also includes a stretch-resisting member that extends through at least a portion of a lumen of the primary coil and is directly or indirectly attached to the primary coil at two locations axially separated from each other to prevent or minimize axial stretching of the primary coil. At one location, the stretch-resisting member is coupled to the primary coil via a flexible anchor assembly disposed within the lumen. The anchor coil is incorporated into the primary coil by disposing the anchor coil windings between the windings of the primary coil.