A fluoroscope projects x-ray images in a video sequence (movie) onto a screen monitor.
Early generation fluoroscopes presented particularly difficult viewing challenges for radiologists. The human retina contains two types of image receptors. Cones (central vision) operate better in bright light, while rods (peripheral vision) are more sensitive to blue-green light and low light. Therefore, the radiologists wear red goggles to filter out blue-green wavelengths to allow the rods to recover peak sensitivity before viewing fluoroscopic images.
To avoid this time consuming accommodation, the industry developed the image intensifier tube in the 1950s. Due to the high amount of individual images during a fluoroscan, a very sensitive amplifier is needed to cut down radiation exposure. Until today, image intensifiers amplify the faint light emitted by the fluorescing screen and the images can be viewed on a monitor. Recently, digital technique replaces the large and bulky image intensifier with flat-panel technology.
Various other components of a fluoroscope system include a gantry, patient table, x-ray tube, filters, collimators, images sensor, camera and computer, most similar to other radiographic systems.
A fluoroscopy system provides the view of moving anatomic structures and is valuable in performing procedures that require continuous imaging and monitoring, such as barium studies, gastrointestinal function tests, cardiac functions, studies of diaphragmatic movement, or catheter placements. A number of technologies are available to record images created during fluoroscopic (fluorographic) exams.

When invented, a fluoroscopic system consisted of x-ray tube, fluorescent screen and x-ray table. In 1950's, the development of the image intensifier revolutionized fluoroscopes. The basic components are extended by a gantry, image intensifier, camera, film and monitor system. The x-ray tube is usually located under the patient table, in opposition to the image intensifier and film cassette or display unit. The patient table can be rotated to an upright position for certain examinations and can be lowered to horizontal position for other imaging procedures. In some instances, the unit can be operated from outside the room.
Today, the transition from conventional to digital fluoroscopy replaces the image intensifier. A flat-panel detector in combination with sensitive image sensors and digital image processing improves the diagnostic ability of a modern system.

Interventional radiology is an area of clinical subspecialty which uses various radiology techniques (such as fluoroscopy, ultrasound, computed tomography, and MRI procedures) to guide procedures such as a biopsy, inserting catheters, place wires, draining fluids, dilating or stenting narrowed ducts or vessels to diagnose or treat different conditions.

See also CT Guided Biopsy, Angioplasty, Coronary Angiogram and Interventional Ultrasound.

A myelography is a radiographic imaging procedure to visualize the spinal canal, the spinal cord, cerebrospinal fluid (CSF), intervertebral disks and nerve roots. A special contrast agent (dye) is injected through a needle into the subarachnoid space of the spinal canal. A myelogram provides a very detailed picture of the spinal cord and spinal column. A fluoroscopy displays the bones and the fluid-filled space of the spine also in motion. An additional computerized tomography (CT or CAT) scan helps to differentiate the spinal conditions better. The indications include disc herniation, spinal stenosis, tumor, and vertebral fracture.

See also Myeloscintigraphy, Fluoroscopic System, Hounsfield Unit, Bone Densitometry, Nonionic Contrast Agents.

A venography (also called phlebography) is the imaging of veins. To perform a venography, a contrast agent is injected into a vein during a fluoroscopy, to show the details of venous structure and abnormalities as for example blood clots and occlusions. The examination of the veins is called venogram.
Other methods include contrast enhanced MR venography and venous ultrasound techniques.

See also Angiogram, CT Angiography, Digital Subtraction Angiography and Computed Tomography.