Views
Different views of the chest can be obtained by changing the relative orientation of the body and the direction of the x-ray beams. The most common views are posteroanterior, anteroposterior, and lateral. In an posteroanterior (PA) view, the x-ray source is positioned so that x-rays enter through the posterior (back) aspect of the chest, and exit out of the anterior (front) aspect where they are detected. To obtain this view, individuals stand facing a flat surface behind which is an x-ray detector. A radiation source is positioned behind the patient at a standard distance, and x-ray beams are transmitted toward the patient.
In anteroposterior (AP) views, the positions of the x-ray source and detector are reversed: x-rays enter through the anterior aspect and exit through the posterior aspect of the chest. AP chest x-rays are harder to interpret than PA x-rays and are therefore generally reserved for situations where it is difficult for the patient to obtain a normal chest x-ray, such as when the patient cannot get out of bed. In this situation, mobile X-ray equipment is used to obtain a lying down chest x-ray (known as a "supine film"). As a result most supine films are also AP.
Lateral views of the chest are obtained in a similar fashion as the posteroanterior views, except in the lateral view, the patient stands with both arms raised and the left side of the chest pressed against a flat surface.
Read more about this topic: Chest Radiograph
Famous quotes containing the word views:
“It is surely a matter of common observation that a man who knows no one thing intimately has no views worth hearing on things in general. The farmer philosophizes in terms of crops, soils, markets, and implements, the mechanic generalizes his experiences of wood and iron, the seaman reaches similar conclusions by his own special road; and if the scholar keeps pace with these it must be by an equally virile productivity.”
—Charles Horton Cooley (1864–1929)
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—Ralph Waldo Emerson (1803–1882)
“Parents must begin to discover their children as individuals of developing tastes and views and so help them be, and see, themselves as thinking, feeling people. It is far too easy for a middle-years child to absorb an over-simplified picture of himself as a sloppy, unreliable, careless, irresponsible, lazy creature and not much more—an attitude toward himself he will carry far beyond these years.”
—Dorothy H. Cohen (20th century)