Anode
Positive electrode of the x-ray tube
Bucky mechanism
Grid that is an integral part of the x-ray table, located below the tabletop and above a cassette tray; decreases the amount of scatter radiation reaching the image receptor, which increases contrast; moves during exposure so that no grid lines appear on
Cassette
Light-proof holder for the image receptor; in computed radiography, the cassette holds the reusable photostimulable phosphor imaging plate; in conventional film-screen radiography, the cassette contains intensifying screens and a sheet of film
Cathode
Negative electrode of the x-ray tube
Collimator
Diaphragm or system of diaphragms made of an absorbing material; designed to define the dimensions and direction of a beam of radiation; device consisting of four rectilinear radiopaque blades that are adjustable to control x-ray field size and shape
Digital imaging
Acquisition of static images in an electronic fashion; conversion of images to a digital format for image manipulation, enhancement, storage, and networking
Diode
Electrical component that possesses polarity with a negative and positive terminal
Flat panel detector
Type of digital detector employing amorphous silicon or selenium detector material, bonded with thin-film transistor technology for digital image creation and amplification
Fluoroscope
Device used for dynamic radiographic examinations; usually consists of an x-ray tube situated underneath the x-ray table and an electronic image detector situated over the x-ray table
Fluoroscopy
Examination by means of the fluoroscope employing image intensification
Goniometer
Angulation scale incorporated into the x-ray tubehead assembly to indicate the degree of x-ray tube angle relative to the image receptor
Hard copy
Radiographic image created on a polyester film medium
Latent image
Invisible image created after x-ray exposure and before image processing
Longitudinal
Lengthwise; along the long axis
Overhead tubecrane
Mechanical support for suspending the x-ray tube and collimator assembly from the ceiling of the radiographic room
Picture archival and communication system (PACS)
Computer network for the transmission, viewing, and archival storage of medical images; often integrated into a larger hospital information system (HIS) and radiology information system (RIS)
Positive beam limitation (PBL)
Form of x-ray beam collimation of field size that ensures the x-ray exposure field is no larger than the receptor size
Postprocessing
Manipulation of medical images after they have been acquired through x-ray exposure, to improve image quality and diagnostic yield
Pyrex glass
Special type of glass that can withstand very high temperatures from the x-ray tube anode
Radiolucent
Describes a material that easily transmits x-ray energy with very little absorption
Real-time images
Images in which dynamic patient motion is visualized instantly as fluoroscopic imaging is occurring
Remnant radiation
All radiation exiting the patient during exposure and ultimately striking the receptor
Soft copy
Visualization of x-ray images using a video monitor for display and interpretation
Spot film
Equipment that permits the acquisition of static images during a dynamic fluoroscopic examination; images are recorded using film or digitally and stored electronically
Tether
Electrical wire connection between a digital detector and the x-ray generator and computer
Transverse
Placed crosswise; situated at right angles to the long axis of a part
Trendelenburg tilt
Table tilt angle in which the patient's head and thorax are lower than his or her legs
Tube angulation
Pivoting the tube at the point where it is attached to its support
Vertical
Perpendicular to the plane of the horizon
X-ray tube
Device that produces x-rays
X-ray tubehead
Equipment consisting of the x-ray tube, collimator, and operator controls; permits manipulation of x-ray tube in many directions for proper positioning