The science of radiation treatment

This section is for those who might want more in-depth information on radiation treatment.

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The science of radiation treatment

Linear Accelerator – An electron gun fires a tiny charged particle (an electron) that travels through a vacuum with an alternating magnetic field around it so the particle gets accelerated to high speed. The speeding particle then hits a target within the machine and its energy is converted to a beam of radiation that comes out and interacts with anything in its path. 

The higher the energy, the more deeply the radiation can penetrate (get into) the body. The way a certain type of radiation behaves is important in planning radiation treatments. 

During radiation treatment you will be placed so the beam is directed to that part of your body that needs to be treated. The radiation beam passes through and is shaped by a device called a multileaf collimator so that it conforms to the shape of the tumour.

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(a) electron gun; (b) vacuum; (c) target; (d) multileaf collimator; (e) beam