Fluoroscopy is used to study moving body structures in real time. A fluoroscope is used to produce a continuous (advanced fluoroscopy machines provide pulsed techniques to lower the amount of radiation) x-ray beam, passing through the body part being examined and transmitted to a monitor so that dynamic images of deep tissue structures can be visualized. Fluoroscopy is primarily used for gastrointestinal exams, genitourinary studies, cardiovascular imaging and for invasive procedures performed by interventional radiologists and angiographers under fluoroscopic guidance. Fluoroscopy can also produce a static record of an image formed on the output phosphor of an image intensifier. The image intensifier is an x-ray image receptor that increases the brightness of a fluoroscopic image by electronic amplification and image minification. Modern fluoroscopy systems combine less radiation with better image quality due to digital image processing and flat-panel technology.
Roentgen's discovery of x-rays related directly to fluoroscopy, because fluorescence on the material in the room draws his attention to the x-ray's properties. In 1896, Thomas A. Edison created the first fluoroscope, consisting of a zinc-cadmium sulfide screen that was placed above the patient's body in the x-ray beam and provides a faint fluorescent image. In first-generation units, the exam room required complete darkness. The users wear red goggles for up to 30 minutes prior to the examination, to adapt the eyes to darkness. After this, the radiologist stared directly at a yellow-green fluorescent image through a sheet of lead to prevent the x-ray beam from striking the eyes.

Image resolution is a measurement of the scanned, printed, or displayed image quality. Picture resolution on a printed photo or page is measured in dots per inch (DPI). For digital files, image resolution is expressed in pixels per inch (PPI).
The quality of pixel-based images is directly determined by resolution choices. Higher image resolution results in more detailed images but requires more storage space in a picture archiving and communication system.
The resolution for x-ray images can be defined as the period length of the finest grid that can be viewed without difficulty.

An intensifying screen is used to intensify the x-ray effect during radiation exposure of the x-ray film. Approximately 5% of the x-ray photons will be absorbed by the film only. Intensifying screens consist of a sheet of inorganic salts that emits fluorescent light when stroked by x-rays. The fluorescent input and output screens of the image intensifier are very similar to intensifying screens.
Calcium tungstate and rare earths are two common salts (also called phosphors) used for intensifying screens. For example, a calcium tungstate (CaWo4) screen can absorb around 40% of the x-ray photons and convert the radiation into light photons. A basic feature of this screen types is related to the position of the k-edge on the energy axis. Tungsten (W) is a heavy element has a k-edge at 69.5 keV, while that for rare earth elements is in around 50 keV.
The fraction of x-rays absorbed by a screen is depending on the speed. Factors affecting the speed of a screen: Mammography cassettes contain usually one intensifying screen, but most others use two screens per film cassette. The intensifying screen as part of a film screen system has been an important component in radiology to reduce the radiation dose of the patient. Today, the conventional film cassette is being replaced by an imaging plate used in digital systems.

See also Actinides, Cinefluorography and Added Filtration.

A mammogram is a low dose x-ray of the breast used to detect and diagnose breast disease, or to provide a baseline reference for later comparison. Multiple images are obtained by different positioning of the breast. The breast compression during mammography is an essential component to produce an optimal diagnostic mammogram. Film mammography units use film to both capture and display the image; digital mammography units use electronic equipment.
A spot compression reduces the thickness of the area of interest and improves contrast and separation of breast tissues.

Mammography is a diagnostic imaging procedure of the breast to detect and evaluate breast disease. Mammography is widely used as a screening method and plays a key role in early breast cancer detection.
The screening mammography is used to detect breast changes in women who have no signs or symptoms or noticed breast abnormalities. The goal is to detect a breast tumor before any clinical signs are observable.
A diagnostic mammography is used to investigate suspicious breast changes, such as a breast lump, an unusual skin appearance, breast pain, nipple thickening or nipple discharge.
A breast screening or standard mammography requires two mammograms from different angles of each breast including craniocaudal view and mediolateral view. Additional images can be made from other angles or focus on microcalcifications or other suspicious areas.
A mammogram is created by special mammography equipment with long wavelength of the used x-rays. Film-screen mammography is still the most widely used technology, but the state of the art technique is digital mammography. Conventional x-ray equipment was used to produce mammograms until dedicated mammography equipment became available in the late 1960s. Film-screen mammography and xeromammography, introduced in the early 1970s, used lower radiation doses and produced sharper mammograms. The second generation of mammography systems has been introduced in the early 1980s. Chief disadvantages of analog mammography include the labor-intensive handling of the cassettes, relatively slow processing time, the lack of a direct interface to the x-ray system, and no post processing possibilities.
Mammograms of high quality should be done with the lowest radiation dose as possible. Adequate breast compression is important due to shortening of the exposure times, immobilization of the breast, reduction of motion and blurring and prevention of overpenetration by means of equalizing breast thickness.
Further breast imaging procedures include breast ultrasound and breast MRI.