| Radiography is a diagnostic procedure in which electromagnetic radiation (x-rays) is used to visualize the interior anatomy of the body. X-rays are beamed through the body and hit a recording medium on the other side. Images form because different tissues absorb x-rays differently as they pass through the body. For example, spaces containing air are darker and solid structures like bones are lighter. The recording medium may be a film similar to photographic film, producing a still picture (plain x-rays), or it can involve electronic detection of the x-rays, producing a live (real-time) moving display on a TV monitor.
Radiography is most commonly done as plain film radiography (plain x-rays). Since x-rays penetrate straight through the body, structures that overlap each other often cannot be seen clearly with a single plain x-ray. Two or three views taken from different angles may help the radiologist determine the relationship of different structures.
Tomography is a special technique that provides greater detail by taking serial cross-sectional x-rays. In computed tomography, these images are synthesized by computer to provide a more detailed picture of the interior anatomy. Other special radiography techniques include angiography, mammography, fluoroscopy, interventional radiography, cineradiography, and digital radiography. |
Source: Medical Disability Advisor