Abstract: A medical device shaft for connection with a handle and for insertion within a body includes an elongated, deflectable shaft having a proximal shaft portion, an intermediate shaft portion, and a distal shaft portion. The elongated, deflectable shaft includes a transition in stiffness from the proximal shaft portion to the distal shaft portion. In a preferred implementation, the shaft includes a plurality of slits that extend perpendicular to a longitudinal axis of the shaft. Varying at least one of the number of slits, the location of slits, the frequency of slits, the orientation of the slits, the size of the slits, and the depth of the slits varies the transition of stiffness.

Abstract: This is an assembly for controllably delivering vaso-occlusive devices to a selected site within the vasculature or other lumen of the human body by the use of a catheter. In particular, the device includes a holding member which is at least generally tubular and has an opening through the tubular wall. The vaso-occlusive device to be delivered has on one end a mating member which may be at least partially pressed into the opening in the wall of the holding member. The mating member attached to the vaso-occlusive member is held in the opening with an interference wire. The interference wire is axially movable within the holding member and has a diameter sufficient to hold the mating member within the wall opening. Upon proximal movement of the interference wire, the mating member becomes free to leave the holding member. The interference wire may be tapered or not. The vaso-occlusive member may be a helically wound coil or a braid or other appropriate form.

Abstract: This invention is a surgical device. In particular, it is a catheter suitable for treating a tissue target within the body, which target is accessible through the vascular system. Central to the invention is the use of a multi-component distal section having an interior stiffener and an exterior tubing member.