Yttrium-90 Microsphere Radioembolization

**Semantic type:** Therapeutic or Preventive Procedure

**Definition:** Antineoplastic treatment consisting of catheter injection of yttrium Y 90 microspheres. When injected into the tumor vascular bed, yttrium Y 90 microspheres occlude tumor blood vessels and deliver a cytotoxic dose of beta radiation to the tumor site, which may result in tumor cell death and tumor regression.

**Synonyms:** - Yttrium Y 90 Microsphere Therapy - Yttrium-90 Radioembolization