Nuclearmedicine 2020

Radiography

Radiography is an imaging technique which uses electromagnetic radiation other than visible light, to view the internal structure of a non-uniformly composed and opaque object (i.e. a non-transparent object of varying density and composition) such as the human body. To create the image, a heterogeneous beam of X-rays is produced by an X-ray generator and is projected toward the object. A certain amount of X-ray is absorbed by the object, which is dependent on the particular density and composition of that object. The X-rays that pass through the object are captured behind the object by a detector (either photographic film or a digital detector). The detector can then provide a superimposed 2D representation of all the object's internal structures. Contrast radiography uses a radio contrast agent, a type of contrast medium, to make the structures of interest stand out visually from their background, whereas plain radiography does not. Each type is best suited to certain indications.