Medical uses of radiation
...
examines the different uses of radiation — for diagnosis and therapy — in
medicine.
Ionizing radiation has two very different uses in medicine — for diagnosis
and therapy. Both are intended to benefit patients and, as with any use of radiation,
the benefit must outweigh the risk. We have touched on this matter of justification
in Chapter 6.
Most people at some time in their lives have an X ray examination to help the
physician diagnose disease or damage in the body. A much less common diagnostic
procedure involves the administration of radionuclides to patients so that detectors
outside the body can be used to observe how organs are functioning. Physicians
use either of these procedures if they cannot make a diagnosis without them.
Radiation doses are generally low, although they can be appreciable in certain
procedures.
Much higher doses are required to treat malignant diseases or malfunctioning
organs sometimes in combination with other forms of treatment. A beam of radiation
may be used to irradiate the affected part of the body or a fairly high activity
of a radionuclide may be administered to the patient.
The use of X rays for examining patients is called diagnostic radiology and the
use of pharmaceuticals labelled with radionuclides for diagnosis or therapy is
called nuclear medicine. When radiation beams are used to treat patients, the
procedure is called radiotherapy.
