Radiolgy terms

• Wavelength


  physical distance between the peaks of each wave.
• Frequency


  is how many keeps of the wave that pass you in one second (peak to peak)
• Energy


  classified as waves because scientist first described energy as waves washing onto a beach
• Infrared


  Electromagnetic waves of frequencies lower than the red of visible light.
• Primary beam


  produces the image on the film
• Scatter radiation


  produces secondary radiatio
• Stationary Anode


  A nonmoving anode, usually found in dental and small portable radiography units
• Rotating Anode


  an anode that turns on an axis to increase x-ray production while dissipating heat
• Cathode (-)


  Serves as the electron source
• Filament


  Creates electrons
• Focusing cup


  Directs electrons across the tube to the target
• mA


  Measurement of current
• kilovoltage (


  kVp or kV)The amount of positive charge
• Tube Rating Chart


  Refers to the maximum exposure characteristics of mAs that permit safe operation
• Heel Effect


  a decrease of x-ray intensity on the anode side of the x-ray beam caused by the anode target angle
• Tube Housing


  Surrounds the x-ray tube and is lined with lead
• Transformers


  Convert or transform current supplied through the main circuit breakers into suitable forms for operation of the x-ray machine
• Autotransformer


  Maintains an even voltage

  Compensates for incoming variability
• Step-up Transformer


  a transformer that increases voltage
• Timer


  Completes the circuits to allow electrons to flow across the tube
• Collimation


  Narrows the primary x-ray beam
• Tube Stand


  Apparatus used to support the x-ray tube
• Volt Meter


  Will show the actual voltage being supplied to the machine
• Line Compensator


  Adjusts the variation in the voltage to the autotransformers
• kV Selector


  allows for the selection of kilovolts- accelerates the electrons across the tube
• Grids


  Flat plate mad of alternating strips of lead (or equivalent material) and radiolucent material
• Stationary Grid


  A high-frequency grid that does not move during the exposure.
• Potter-Bucky Grid


  Moving grid located under the table
• X-ray Apparatus


  Portable Units
• X-ray Beam


  Penetration and absorption of the Beam. The radiopacity of any substance depends on:
• Cassettes


  Holders for both the film and intensifying screen

  Must be light proof
• photostimulable phosphor


  crystals that store the energy of the remnant x-ray beam and release it as light when stimulated by a laser
• scintillation phosphor


  crystals that emit light in response to an x-ray interaction.
• Spatial resolution


  is the image in space that is expressed in line pairs per millimeter.
• Contrast Resolution


  expressed as a the values of back and white.
• histogram


  graphic description of each pixel value in the image.
• Dynamic Range


  the range of exposures that may be captured by a detector
• Post-Processing


  changing or enhancing the electronic image for the purpose of improving its diagnostic quality
• Digital Imaging and Communication in Medicine (DICOM)


  This is a universal digital image format that allows for digital images to be shared between vendors' software
• Picture Archiving and Communications Systems (PACS)

  After the image is created, it must be archived. The storage for these images is on a computer