X-rays are used to visualize internal organs and structures and to serve as a diagnostic aid. Radiation is also used therapeutically in the treatment of malignancy. A radiograph is a permanent record of the picture produced on a radiographic film. Items in the body that obstruct the passage of x-ray, such as bone, are termed radiopaque. A structure, such as lung tissue, that permits the passage of x-rays is considered radiolucent. Contrast medium is used to make a particular structure visible on the radiograph.
The patient’s position is determined by the purpose of the examination and the area examined. The various types of radiographic views include anteroposterior, posteroanterior, lateral, oblique, supine, and prone. X-rays that are directed from the front to the back of the body are called anteroposterior views. The patient is facing the x-ray tube and the posterior aspect is against the radiographic film. The patient’s back would face the x-ray tube for a posteroanterior view. When performing the lateral view, the x-ray beam passes from one side of the patient’s body to the other. For an oblique view, the body is positioned at an angle or in a semilateral position. Supine positioning has the patient lying on his back for the x-ray. The patient is positioned face down for a prone radiograph.
The medical assistant should understand the purpose and proper instructions for commonly performed radiographic examinations. Other types of radiological testing that may be performed in a medical office include the following.