Fluoroscopy

Fluoroscopy (), informally referred to as "fluoro", is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a surgeon to see the internal structure and function of a patient, so that the pumping action of the heart or the motion of swallowing, for example, can be watched. This is useful for both diagnosis and therapy and occurs in general radiology, interventional radiology, and image-guided surgery. In its simplest form, a fluoroscope consists of an X-ray source and a fluorescent screen, between which a patient is placed. However, since the 1950s most fluoroscopes have included X-ray image intensifiers and cameras as well, to improve the image's visibility and make it available on a remote display screen. For many decades, fluoroscopy tended to produce live pictures that were not recorded, but since the 1960s, as technology improved, recording and playback became the norm. Fluoroscopy is similar to radiography and X-ray computed tomography (X-ray CT) in that it generates images using X-rays. The original difference was that radiography fixed still images on film, whereas fluoroscopy provided live moving pictures that were not stored. However, modern radiography, CT, and fluoroscopy now use digital imaging with image analysis software and data storage and retrieval. Compared to other x-ray imaging modalities the source projects from below leading to horizontally mirrored images, and in keeping with historical displays the grayscale remains inverted (radiodense objects such as bones are dark whereas traditionally they would be bright).