Stretch resistant therapeutic device

An apparatus for release and deployment of a stretch resistant therapeutic device within a patient's vasculature, comprising:

• a vasoocclusive coil having a proximal end and a distal end, said vasoocclusive coil defining a lumen between said proximal and distal ends, said vasoocclusive coil including a distal therapeutic portion and a proximal stem portion, said proximal stem portion including at least one rounded member;
• an elongated pusher member having a distal end adjacent to said proximal end of said vasoocclusive coil;
• a stretch resistant member extending through said lumen of said vasoocclusive coil, said stretch resistant member being fixedly attached to said vasoocclusive coil at the distal end of the vasoocclusive coil and detachably mounted to the distal end of the elongated pusher member to allow for placement of the vasoocclusive coil within the patient's vasculature;
• and
• a body of constraining material having a tubular cross-section forming a tubular collar mounted to the distal end of the elongated pusher member detachably retaining said at least one rounded member, said body of constraining material having a stressed configuration engaging said at least one rounded member of the stem proximal portion of the vasoocclusive coil and a recovered configuration withdrawn from said at least one rounded member of the proximal stem portion of the vasoocclusive coil, said distal end of said elongated pusher member contacting said at least one rounded member when said body of constraining material changes from said stressed configuration to said recovered configuration withdrawn from said at least one rounded member of the proximal stem portion of the vasoocclusive coil to dislodge said at least one rounded member from said body of constraining material to release said vasoocclusive coil from said elongated pusher member.