Intermediate
Technical
IVT
photon beam
Pronunciation: FOH-ton beam
High-energy electromagnetic radiation used in external beam radiation therapy, typically from linear accelerators.
Full Definition
Photon beams consist of high-energy electromagnetic radiation (X-rays) produced by medical linear accelerators for cancer treatment. These beams can penetrate deeply into tissue and are the most common form of external beam radiation therapy. Photon beam energies typically range from 6 to 25 megavolts (MV), with higher energies providing greater penetration but potentially more scattered radiation.
Usage
Usage note: Distinguish from particle beams such as electrons or protons.
In Context
- "The treatment plan utilizes 6 MV photon beams from four different angles." — Technical specification
- "Photon beam attenuation through bone must be accounted for in dose calculations." — Physics protocol
Also known as
X-ray beam
megavoltage photons
Contrasted with
electron beam
proton beam
Don't confuse with
electron beam
neutron beam