Imaging studies Health Article

Definition

Imaging studies are tests performed with a variety of techniques that produce pictures of the inside of a patient's body.

Description

Imaging tests are performed using sound waves, radioactive particles, magnetic fields, or x rays that are detected and converted into images after passing through body tissues. Dyes are sometimes used as contrasting agents with x-ray tests so that organs or tissues not seen with conventional x rays can be enhanced. The operating principle of the various techniques is based on the fact that rays and particles interact differently with various types of tissues, especially when abnormalities are present. In this way, the interior of the body can be visualized and pictures are provided of normal structure and function as well as of abnormalities. In the fields pertaining to mental health including psychology and psychiatry, imaging is often used to help rule out other health problems that could be causing symptoms (such as brain tumors), and imaging studies are often used in research. Once a person's diagnosis has been established, various imaging techniques may help to confirm the diagnosis, and also serve as a way to study the disorder. The imaging techniques may shed new light on the way the disorder affects the brain, so that new treatment methods can be discovered.

Computed tomography scan (CT scan)

Computed tomography, or computed axial tomography (CAT), scans show a cross-section of a part of the body, such as the brain. In this technique, a thin x-ray beam is used to produce a series of exposures detected at different angles. The exposures are fed into a computer which overlaps them, yielding a single image analogous to a slice of the organ or body part being scanned. A dye is often injected into the patient so as to improve contrast and obtain images that are clearer than images obtained with regular x rays.