Digital 9-12

  1. An electronic version of the radiologist’s reading room and the file room:
  2. Electrical signals from CR and DR are:
    similar for both systems
  3. Preprocessing takes place in the:
    computer whre algorithms determine histogram
  4. Postprocessing is done by:
    the technologist
  5. A graphical representation of exposure values collected form the imaging plate:
  6. Exposure data recognition processes only the:
    optimal density exposure range
  7. The data recognition program searches for anatomy recorded on the imaging plate by finding the ____ and then elimitating the ____.
    collimation edges; scatter outside the collimation
  8. Low kVp gives a ____ histogram while high kVp gives a ____ histogram.
    wider; narrower
  9. On the histogram graph, the y-axis is the ____ and the x-axis is the ____.
    # of pixels for each exposure; amount of exosure
  10. The shape of a histogram is _____ specific.
  11. Aliasing results in:
    moire effect
  12. When exposure is greater or less than what is needed to produce an image, ____ occurs.
    Automatic rescaling
  13. A table of the luminance values derived during image acquisition:
    look-up table (LUT)
  14. LUT is used to:
    correct values
  15. LUT can be graphed by placing the original values on the __axis and the new values on the ___ axis.
    horizontal, vertical
  16. With a LUT, the brightness can be increased or decreased by:
    moving the line up or down the y-axis
  17. Latitude is also called:
    margin of error
  18. Latitude refers to the ____ that can be used and stillr esult in a diagnostic quality image.
    range of exposure
  19. The exposure latitude for digital imaging receptors is ___ than thatof screen/film exposures due to ____.
    greater; dynamic range
  20. Histograms show a wide range of exposure because of:
    automatic resscaling of the pixels
  21. More than 50% below ideal exposure results in:
    quantum mottle
  22. More than 200% above ideal exposure results in:
    contrast loss
  23. What feature increases latitude while preserving contrast and vitually eliminates detail loss in dense tissues?
    enhanced visualization image processing (EVP)
  24. What is MTF?
    Modulation transfer function
  25. The ability of a system to record available spatial frequencies is known as:
    Modulation transfer function
  26. The sum of the components in a recording system cannot be:
    greater than the system as a whole
  27. What quantifies the contribution of each system component to the overall efficiency of the entire system?
  28. A perfect system would have an MTF of:
    1 or 100%
  29. Phosphor light spreads which reduces system ____. The more light spread, the lower the ____.
    efficiency, MTF/image quality
  30. The initial digital image appears linear when graphed because:
    all shades of gray are visible
  31. Image contrast is controlled by using a parameter that changes the _____ of the _____.
    steepness; exposure gradient
  32. Detail or sharpness is referred to as:
    spatial frequency resolution
  33. Sharpness control is referred to as:
    spatial frequency processing
  34. Two major types of spatial frequency filtering:
    edge enhancement and smoothing
  35. ____ occurs when fewer pixels in the neighborhood are included in the signal average.
  36. After the signal is obtained for each pixel, the signals are ____ to shorten processing time and storage.
  37. The more pixels involved in the averaging, the ____ the image appears.
  38. The signal strength of one pixel is averaged witht he strength of ____.
    adjacent pixels, or neighborhood pixels
  39. High pass filtering is accomplished by:
    amplifying frequencies of areas of interest
  40. High pass filtering increases ____ and ____ and is useful for enhancing ___ structures, but can be noisy.
    contrast, edge enhancement, large
  41. Smoothing, also known as ____, occurs by averaging each pixels frequency with surrounding pixel values to remove ____.
    low-pass filtering, high-frequency noise
  42. Low-pass filtering is useful for viewing small structures such as:
    fine bone tissues
  43. The most common image processing parameters are those for:
    brightness and contrast
  44. ____ controls how light or dark and image is and ____ controls the contrast.
    Window level, window width
  45. Unexposed borders around the collimation edges results in:
    veil glare
  46. Removing the white unexposed borders results in an oerall smaller number of ____ and reduces the amount of ____.
    pixels, information to be stored
  47. Two basic types of magnification techniques in digital systems:
    magnifying glass and zoom
  48. The first PACS were used int he early ____ and generally served ____.
    1980's, one single modality
  49. PACS can be broekn into 3 parts:
    image acquisition, display workstations, and archive servers
  50. First modality of PACS:
  51. An archive server is the ____ for PACS.
    file room
  52. The central part of the PACS; houses all of the historic data along with the current data being generated:
    the archive
  53. The hardware and softwear infrastructure of a computer system is the :
    system architecture
  54. In a PACS. the system architecture normally consists of:
    acquisition devices, display workstations, and an image management system.
  55. Three common PACS architectures:
    client/server based, distributed systems, web-based systems
  56. In a client/server based system, images are sent directly to the ____ after acquisition and are centrally located.
    archive server
  57. In this system, acquisition modalities send the images to a designated reading station and possibly to review stations, then sent to the archive server once the images have been read:
    Distribuited or Stand-alone systems
  58. Most interactive part of the PACS:
    Display workstation
  59. The brain of the archive system; contains the master database, controls movement of images and interfaces withthe RIS and HIS:
    image manager
  60. Two major types of film digitizers:
    laser and CCD; both equal in quality but CCD cheaper
  61. Common uses for film digitizers:
    teleradiology, comparison with outside or old films, film duplication, computer aided diagnosis
  62. Two major types of imagers (printers):
    wet (chemical) laser printers and dry laser imagers
  63. A plan for the systemic obsservation and assessment of the different aspects of a project service or facility to make certain that standards of quality are being met:
    Quality Assurance
  64. A comprehensive set of activities designed to monitor and maintain systems that produce a procuct:
    Quality Control
  65. Three major categories of Quality Control:
    Acceptance testing, rountine maintenance, and error maintenance
  66. PACS QC activities:
    display quality form monitor and film, processing speed, network transfer speed, and data integrity
  67. Who requires compliance with standards of practice to ensure quality in any imaging system?
    american college of radiology
Card Set
Digital 9-12
Digital 9-12