rad tech ch 7

  1. Attenuation
    process by which a beam of radiation is reduced in energy when passing through tissue or other materials
  2. Central Ray
    theoretical center of a beam of radiation
  3. Contrast:
    difference between adjacent densities on a radiograph
  4. Density:
    degree of darkening of exposed and processed photographic or radiographic film
  5. Distortion:
    misrepresentation of the true size or shape of an object
  6. Dynamic
    with motion
  7. Fog:
    unwanted exposure or film densities
  8. Grid:
    device consisting of thin lead strips designed to permit primary radiation to pass while reducing scatter radiation
  9. Half-Value Layer:
    amount of filtration necessary to reduce the intensity of the radiation beam to one half its original value
  10. Image Receptor:
    medium used to capture the image for recording, such as x-ray film or a digital imaging plate
  11. Intensifying Screen:
    layer of luminescent crystals placed inside a cassette to expose x-ray film efficiently and thereby significantly reduce patient dose
  12. Inverse Square Law:
    mathematical formula that describes the relationship between radiation intensity and distance from the source of the radiation
  13. Kilovoltage Peak (kVp):
    measure of the potential difference, which controls the quality and quantity of x-ray photons produced in the x-ray tube
  14. Latent Image:
    invisible image created after exposure but before processing
  15. Milliampere Seconds (mAs):
    measurement of milliamperage times seconds, which controls the quantity of x-ray photons produced in the x-ray tube
  16. Penetrating Ability:
    ability of an x-ray beam to pass through an object, controlled by the kVp of the beam
  17. Penumbra:
    fuzzy border of an object as imaged radiographically
  18. Photon:
    quantum or particle of radiant energy
  19. Positive Beam Limitation (PBL):
    automatic collimation system used on diagnostic x-ray units
  20. Primary Radiation:
    x-ray beam after it leaves the x-ray tube and before it reaches the object
  21. Radiolucent
    permitting the passage of x-rays or other forms of energy with little attenuation
  22. Radiopaque:
    not easily penetrable by x-rays or other forms of radiant energy
  23. Recorded Detail:
    representation of an object's true borders
  24. Relative Speed:
    relative measurements of the speed of a radiographic film and intensifying screen system
  25. Remnant Radiation:
    radiation resulting after the x-ray beam exits the object
  26. Resolution:
    a measurement of the recorded detail on a radiograph
  27. Scatter Radiation:
    radiation produced from x-ray photon interactions with matter in such a way that the resulting photons have continued in a different direction
  28. Source-to-Image Distance (SID):
    the distance between the source of the x-rays (usually the focal spot of the x-ray tube) and the image receptor
  29. Static:
  30. Umbra:
    true border of an object as imaged radiographically
Card Set
rad tech ch 7
chapter 7 vocabulary words