An apparatus includes an elongate wire (solid or hollow) having a distal end section for detachment and delivery to a target location, the wire also having a discontinuity located rearwardly of the distal end section for rupturing when vibrational energy is applied to the wire, and a vibrational energy source couples to the proximal end of the wire for selectively applying vibrational energy to the wire to travel to the discontinuity and causes detachment of the end section.