Radiotherapy

The main way that doctors use radiotherapy is the external beam method where high concentrations of gamma rays are fired into the body at the tumor. Scientists call them gamma rays but they are not gamma rays, gamma rays are far too difficult to obtain a scientist would have to get a radioactive piece of rock and channel the pure radiation into the body.

Instead of pure gamma radiation scientists use high energy x-rays, this is because they are easier to get hold of as scientists can make these x-rays in a special machine, x-rays will have the same effect as the gamma rays would because they are very close on the electro-magnetic spectrum. This form of radiotherapy is also called teletherapy. The x-rays for this procedure are made by bombarding a high atomic number material with electrons. If the target is removed (and the beam current decreased) a high energy electron beam is obtained.

Another method of radiotherapy is internal radiotherapy: This is when a doctor injects a radioactive substance into the blood-stream such as iodine 13. Then a special camera is used to scan the body for the radioactive substance, it shows up well on the camera and it is not a static image it is moving so the doctors can see how well the body is functioning, and to see where the problems in the body are and then decide how to treat the patient.