180 test2.txt

  1. What is the importance of spectral matching in selection of screen film combinations?
    Rare earth screens; it must match
  2. Amber filter
    Blue sensitive film
  3. Red filter
    Green and blue
  4. Proper film storage
    • Temp 20 degree Celsius 68F
    • Humidity >60%
    • Shelf life - cool dry place
  5. Other name for fixer
  6. Principal of development
    Convert latent image to manifest
  7. Why does film go through fixer tank?
    Washes off the unaffected silver halide
  8. Brown film
    Fixer retention
  9. Physical qualities required for to be used as a intensifying screen base?
    Polyester plastic
  10. Typical radiograph intensifying screen
    Base,reflective layer,phosphor,base,contact felt, low z front , low z back
  11. Radiographic film contributes to latent image?
    Fewer than 1%
  12. Why are two screens placed in a radiographic cassette ?
    Reduce patient dose
  13. Name 5 phosphors
    Barium flurochloride, barium sulfate,zinc sulfide, calcium tungstate, lanthanum
  14. Quantum mottle
    Radiographic noise produce by the random interaction of x ray with intensifying screen
  15. Four exposure technique factor; how does each affect OD
    • Kvp - number of X-rays in image forms beam
    • mA - number of X-rays produced radiation quantity
    • Exposure time (s) minimize motion blur the can occur during patent motion.
    • SID - determines the intensity of X-ray beam at IR
  16. Components of total X-ray beam filtration
    Inherent,compensating, added filtration
  17. Why is it important to keep exposure time as short as possible
    Dosage minimize patient motion blur
  18. Large focal spot
    Sufficient mAs used to image thick or dense body parts, shorter exposure time. More X-rays at anode
  19. Small focal
    Electron interaction over smaller area of anode; finer detail
  20. OD
    • Black OD 3 or greater
    • Clear is less than 0.2
    • Light OD of 2
    • Useful range 2?
  21. High OD
    Over exposure too dark
  22. Low OD
    Under expose
  23. Change in OD req what technique
    • Fix distance
    • MAs used to control OD change in 30% mAs is used to produce a visible image
  24. Body habitus
    Thicker body = more strength
  25. Advantage of large focal spot over small
    Large - more X-rays
  26. Contrast
    Difference in OD between adjacent anatomical structures or the variations in OD on a radiograph
  27. High contrast
    Bones spinal column
  28. Low contrast
    Psoas muscle, kidney
  29. Radiographic film cross section
    Super coat, emulsion, adhesive, base, adhesive, emulsion, supercoat
  30. 90 second processor
    Developer fixer washing drying
  31. Process whereby latent image is created in one crystal of the film emulsion
    The exposed crystal , electron collected at sensitivity center. These elections concert silver jobs to atomic silver
  32. Gloves goggles
    Toxic skin burns eye irritations
  33. Proper dark room procedure
    Color watt distance from film
  34. Film damp
    Dryer is out
  35. Reg screen film
    Double emulsion
  36. Mammography
    Single screen single side emulsion
  37. Photon
    Electromagnetic radiation that has neither mass nor electric charge but interacts with matter as though it's a particle
  38. W =
  39. Alpha particle
    Particulate from of ionizing radiation that consists of two photon an two neutron.

    Helium emitted from nucleus of radioactive atom
  40. Fundamental particles within an atom
    Electron proton neutron
  41. Property of an atom does biding energy describe
    Electron closer to nucleus Stronger binding
  42. Can atoms be ionized by Changing number of positive charges ?
    No, bound strongly together and that action would change type of atom
  43. How are ion pairs formed?
    Opposite charged particle come together
  44. Why doesn't an electron spontaneously fly away from nucleus atom ?
    Tightly bonded strength = certain amount of energy to release
  45. X-rays
    • Electron cloud
    • Produced outside nucleus of excited atoms
  46. Gamma ray
    Produced inside the nucleus of radioactive atoms
  47. Alpha particles , beta particles
    • Nucleus
    • Particulate radiation
  48. Energy
    Ability to do work
  49. Derived quantity
    Secondary quantities combination one or more of the three base quantities

    Volume density velocity
  50. Ionizing radiation
    Any electromagnetic that had sufficient energy to remove an electron from an atom
  51. Air kerma
    • 1/1000 of a rad
    • 100 ergs of energy absorbed per gram of tissue
  52. Average level of natural enviromental radiation
    300mrad yr
  53. The Coolidge tube
    First heated filament X-ray tube
  54. Fluorscopy
    Real time x ray
  55. Acceleration
    Rate of change over time
  56. Barium platinocyanide
    Phosphor fluorescent material
  57. 1895
    Roentgen discovers X-rays
  58. Roentgen Noble prize
  59. Snooks transformer
  60. Coolidge hot cathode x eh tube
  61. Weight different from mass
    • Weight is determined by gravity
    • Mass is constant
  62. For examples of electromagnetic radiation
    X rays gamma rays visible light radio waves microwaves infrared radiation ultra violet radiation
  63. X-rays vs electromagnetic radiation
    X-rays interact at electron level or nuclear level

    Electromagnetic interact molecules cells
  64. Purpose of X-ray filtration
    Lower patient radiation dose
  65. Formation of negative ion and positive ion
    X-rays electron absorbs energy and is release from atom + - ion pair
  66. Spatial resolution
    Ability to image small objects that have high subject contrast
  67. Spectral matching
    Rare earth screens only in conjunction with film emulsion that have lift absorption match light emission of screen
  68. Phosphor
    Active layer of the radiographic intensifying screen closest to radiographic film
  69. Luminescence
    Emission of visible light
  70. Kvp
    Measure of the maximum electrical potential
  71. mAs
    Product of exposure time and x ray tube current. Measure total number of electron
  72. Beam penetrability
    Ability of an X-ray beam to penetrate tissue
  73. Sid
    Distance from X-ray tube to IR
  74. Inherent filtration
    Filtration of useful X-ray beams provided by the permanently installed components of an film emulsion

    X-ray tube housing assembly an glass must match light emission
  75. Solvent
    Liquid in to which various solids and powers can be dissolved
  76. Sensitive center
    Physical imperfections on the lattice of emulsion layer that occur during the filming manufacturing process.
  77. Latent image
    Unobservable image stored in the silver halide
  78. Silver halide
    Active ingredient of radiographic emulsions
  79. Spectral matching
    Use of rare earth screens only in conjunction with film emulsions that have light absorption characteristics matched the light emissions of the screen
  80. Artifact
    Unintended optical density on a radiograph or another film type of IR
  81. Radiation fog
    Artifact caused by unintended exposure to radiation
  82. Shelf life
    How long before it expires
  83. Orthochromatic
    Referring to blue it green sensitive films
  84. Screen speed
    Relative number used to identify the efficiency of conversion of X-rays in to usable light
  85. Archival quality
    Image does not deteriorate with age but remains in original state
  86. High kvp
    Low contrast
  87. Low kvp
    High contrast
  88. 90 sec processor
    • Developing 22sec
    • Fixer 22
    • Washing 20
    • Drying 26
  89. Film sizes
    • 8x10
    • 10x12
    • 11x14
    • 14x17
  90. High contrast
    Smaller crystals uniform grain size
  91. Low contrast
    Larger crystals wider range sizes
  92. Direct exposure film
    • Thicker emulsion an more crystals
    • Not sensitive to light
    • Increased dose
    • Very detailed
  93. Screen construction
    • Polyester plastic base - support layer
    • Phosphor layer - active layer
    • Reflective layer - increase screen efficiency
    • Protective coating
  94. Isotropically
    X-rays emit ^ equal intensity in all directions
  95. X-rays emitted through window or port
    Useful or primary beam
  96. X-ray tube made of
    Pyrex glass or metal enclosure to withstand high heat load and minimize X-ray absorption
  97. Cathode two parts
    Filament focusing cup
  98. Outer shell electrons boiled off
    Thermionic emission
  99. Anode +
    Conducts electricity radiates heat contains target

    Two types stationery and rotating
  100. Anode heat
    • 99% kinetic energy to hear
    • 1% converted to X-rays
  101. Anode heel affect
    The smaller the anode angle the larger the heel affect
Card Set
180 test2.txt