Megavoltage
Pronunciation: MEG-ah-volt-ij
High-energy radiation beams with energies greater than 1 million electron volts, typically used for deep tumor treatments.
Full Definition
Megavoltage radiation refers to high-energy photon or electron beams with energies measured in millions of electron volts (MeV), typically ranging from 4 MV to 25 MV for photons in clinical practice. These high-energy beams provide superior penetration characteristics compared to kilovoltage beams, with skin-sparing properties and reduced bone absorption that make them ideal for treating deep-seated tumors. Megavoltage beams are produced by linear accelerators and offer the energy spectrum necessary for modern conformal radiation therapy techniques.
Usage
Usage note: Abbreviated as MV when referring to specific beam energies (e.g., 6 MV, 18 MV).
In Context
- "The treatment plan specified 15 MV photons for optimal dose distribution in the thoracic tumor." — Treatment planning report
- "Megavoltage beams provide better skin sparing compared to lower energy radiation." — Medical physics consultation