Mechanically detachable vaso-occlusive device
A device for delivering an occlusive element includes an elongate pusher member having a lumen. A locking member is disposed within the lumen of the elongate pusher member. A moveable elongate releasing member is disposed within the lumen of the elongate pusher member. A filament is secured to the distal end of the elongate releasing member. The occlusive member is locked to the elongate releasing member when the filament passes through a securing member on the occlusive member and is pinched or wedged between the locking member and the elongate releasing member. The occlusive element is in an unlocked state when the elongate releasing member is retracted proximally relative to the elongate pusher member. The filament, along with the elongate releasing member, are retracted proximally until the filament is detached or uncoupled from the securing member of the occlusive member.
1. An occlusive device, comprising:
an elongate pusher member having a distal end and a proximal end and a lumen extending between the distal and proximal ends;
a locking member disposed in the lumen of the elongate pusher member;
an elongate releasing member having a distal end and a proximal end, the distal end including a filament attached thereto, the elongate releasing member being moveable within the lumen of the elongate pusher member; and
an occlusive element including a securing member positioned at a proximal end;
wherein the securing member is locked to the elongate releasing member when the filament is looped through the securing member and a distal end of the filament is looped back to be pinched between the locking member and the elongate releasing member such that the filament is secured to the securing member thereby preventing axial movement of said occlusive element, and unlocked when the elongate releasing member is retracted proximally relative to the elongate pusher member such that the filament passes out of the securing member thereby releasing said occlusive element,
wherein the locking member is sized to prevent the elongate releasing member from deploying out the distal end of the elongate pusher member.
2. The device of claim 1 , wherein the locking member includes one of an edge and a surface that pinches the filament against the elongate releasing member.
3. The device of claim 1 , the elongate releasing member including a tapered portion, wherein the filament is pinched between the tapered portion and the locking member in a locked configuration.
4. The device of claim 1 , further comprising a blocking member disposed at a distal end of the elongate pusher member, the blocking member including an aperture dimensioned to receive the filament but prevent passage of the securing member.
5. The device of claim 1 , the distal end of the elongate pusher member having a stiffness that is less than the stiffness of the proximal end of the elongate pusher member.
6. The device of claim 5 , wherein the distal end of the elongate pusher member comprises a coil member.
7. An occlusive device, comprising:
an elongate pusher member having a distal end and a proximal end and a lumen extending between the distal and proximal ends;
a coil member secured to the distal end of the elongate pusher member;
a locking member disposed in the lumen of the elongate pusher member;
an elongate releasing member having a distal end and a proximal end, the distal end including a filament attached thereto, the elongate releasing member being moveable within the lumen of the elongate pusher member; and
an occlusive element including a securing member positioned at a proximal end, wherein the securing member is locked to the elongate releasing member when the filament is looped through the securing member and a distal end of the filament is looped back to be wedged between the locking member and the elongate releasing member such that the filament is secured to the securing member thereby preventing axial movement of said occlusive element, and unlocked when the elongate releasing member is retracted proximally relative to the elongate pusher member such that the filament passes out of the securing member thereby releasing said occlusive element,
wherein the locking member is sized to prevent the elongate releasing member from deploying out the distal end of the elongate pusher member.
8. The device of claim 7 , wherein the locking member includes one of an edge and a surface that pinches the filament against the elongate releasing member.
9. The device of claim 7 , the elongate releasing member including a tapered portion, wherein the filament is wedged between the tapered portion and the locking member in a locked configuration.
10. The device of claim 7 , further comprising a blocking member disposed at a distal end of the coil member, the blocking member including an aperture dimensioned to receive the filament but prevent passage of the securing member.
11. The device of claim 10 , wherein the blocking member is disposed inside a lumen of the coil member.