Agents
The microspheres themselves are made of glass or resin. Inside the microspheres is the isotope yttrium-90, which has beta-emission with a half-life of 2.6 days. Currently there are 2 types of microspheres: TheraSphere and SIR-Spheres, which differ in their radioactivity per sphere and embolic effect.
| Parameter | Resin | Glass |
|---|---|---|
| Trade name | SIR-Spheres | Therapheres |
| Manufacturer and location | Sirtex Medical, Lane Cover, Australia | MDS Nordion, Kanata, Canada |
| Diameter | 20-60 µm | 20-30 µm |
| Specific gravity | 1.6 g/dL | 3.6 g/dL |
| Activity per particle | 50 Bq | 2500 Bq |
| Number of microspheres per 3 GBq vial | 40-80 million | 1.2 million |
| Material | resin with bound yttrium | glass with yttrium in matrix |
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Read more about this topic: Selective Internal Radiation Therapy
Famous quotes containing the word agents:
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—Ralph Waldo Emerson (1803–1882)
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