Microspheres with sacrificial coatings for vaso-occlusive systems

A method of treating a vascular malformation at a targeted site within a patient's vasculature, comprising the steps of:

• (a) navigating a catheter working end to the targeted site in the patient's vasculature;
• (b) introducing flowable media from the catheter working end into the vascular malformation wherein said flowable media carries a volume of microspheres, each microsphere having a sacrificial shell portion that surrounds an interior core portion of either a first or second polymerizing composition that upon interaction cause a polymerization process;
• (c) activating energy delivery means carried at the catheter working end to cause disintegration of the sacrificial shell portions of the microspheres;
• and
• (d) causing interaction of the first and second polymerizing compositions thereby altering the flowable media to a substantially solid media volume to provide occlusive media.

A vaso-occlusive system, comprising:

• a fluid media carrying a volume of microspheres of first and second types,
• the first type of microsphere having a sacrificial shell portion that surrounds an interior core of a first composition;
• the second type of microsphere having a sacrificial shell portion that surrounds an interior core of a second composition;
• and
• wherein interaction of said first and second compositions causes a polymerization of the volume of fluid media.