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SIR-Spheres® Y-90 resin microspheres

How It Works

SIR-Spheres® Y-90 resin microspheres take advantage of the unique blood supply of the liver, which is different from that of the rest of the body.

How it works
  • Most of the blood that feeds healthy liver tissue comes from veins, and it flows from the bowel to the liver.
  • On the other hand, most of the blood that feeds tumors in the liver is from arteries.
  • SIR-Spheres are injected through arteries that supply liver tumors.
  • Because of their small size and weight, the microspheres are taken by the blood flow to the small blood vessels surrounding the tumor where they lodge.
  • Radiation is then delivered directly to the tumor cells in order to destroy them.
  • This allows tumors to receive radiation from inside the body in a way that targets the tumors yet protects healthy liver tissue.