ultrasound cards

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ultrasound cards
2010-06-24 17:27:39

physics questions
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  1. What is a logarithm?
    Number of 10's that are multiplied to create original number
  2. What is the log of 1000?
  3. What is the log of 10,000?
  4. Is distance and attentuention
    a) inversely related
    b) directly related
    c) not related
    Directly related
  5. What 3 processes contribute to attentuation?
    • 1) Reflection
    • 2) Scattering
    • 3) Absorption
  6. What are the 2 forms of reflection?
    Specular and Diffuse
  7. What boundary is found with specular reflection?
    • Smooth boundary
    • Sound is reflected in only one direction
  8. What boundary is found with Diffuse reflection?
    • Irregular surface boundary
    • Sound is reflected in more than one direction
  9. What is the medium of lung tissue that causes scattering?
  10. What is the definition of PRF?
    • Pulse repetition frequency
    • The number of pulses per 1 second
  11. What is the definition of PRP?
    • Pulse repetition period
    • Time from beginning of 1 pulse to the beginning of the next pulse
  12. What is pulse duration?
    The time from beginning of the pulse to the end or "talk time"
  13. What is power?
    Rate of energy transfer measured in watts
  14. What is Propagation speed?
    • The time it takes to travel through medium.
    • The medium determines the speed.
  15. Why does sound travel fast in bone?
    Bone has a higher stiffness level and lower density level
  16. What is Frequency?
    The number of events in a specific duration of time
  17. What is intensity?
    Concentration of energy in sound beam
  18. What is the relationship of Period and Frequency?
    Inversely related
  19. What is the distance of one complete cycle?
  20. Why does sound travel slow in air?
    Density is increased and stiffness is decreased
  21. What are units of attenuation?
  22. What is a quick way to find log?
    • Count the number of 0's
    • 100=2
    • 1000=3
    • 10,000=4
  23. Water has low attenuation

    T or F
  24. Air has high attenuation

    T or F
  25. As path length increases, what happens to Attenuation coefficent?
    a) increases
    b) decreases
    c) remains the same
    Remains the same
  26. When scanning a carotid artery which transducer do you choose?
    1) 7.0
    2) 3.5
  27. What is the unit of Attenuation coefficient?
  28. In a boundary where impedance is the same, what part of sound wave is reflected back?
    • 0% is reflected
    • 100% is transmitted
  29. What law is demonstrated by rules of refraction?
    Snell's Law
  30. Does attentuation increase or decrease as path length increases?
  31. What are the names for Lateral Resolution?

    Hint - 4
    • Lateral
    • Angular
    • Transverse
    • Azimuthal
  32. What are 3 synonyms for PZT?
    • Element
    • Crystal
    • Ceramic
  33. What is the definition of Hemodynamics?
    Study of blood moving through circulatory system
  34. What does Volume rate measure?
    How much
  35. What does Velocity measure?
    How fast
  36. Units of flow are
    volume/time or distance/time
  37. Units of velocity are
    volume/time or distance/time
  38. What are the 3 forms of blood flow?
    • Pulsatile
    • Phasic
    • Steady
  39. Pulsatile flow accelerates and decelerates from
    Cardiac Contraction
  40. Phasic blood flow accelerates and decelerates from
  41. Steady flow occurs when fluid moves at a _____ speed of velocity?

  42. Laminar flow is

    Chaotic or
    Aligned and Paralell
    Alligned and Paralell
  43. What is the Reynolds number for Laminar flow?
    less than 1500
  44. Turbulent flow is

    Chaotic or
    Aligned and paralell
  45. What are sounds associated with turbulent flow?
    Murmur, Bruit, and thrill
  46. What is the definition of transducer?
    Transforms electrical energy into acoustic energy
  47. Definition of Pulser?
    Determines the amplititude, pulse repetition period (PRP) and pulse repetition frequency (PRF)
  48. Definition of Beam Former?
    Determines the firing delay pattern for phased array systems
  49. Definition of Receiver?
    Transforms signals from transducer into a form suitable for display
  50. Definition of Storage?
    Archives U/S studies in videotape, paper printout, photos, film, CD or hard drives
  51. Definition of Master Synchronizer?
    Maintains and organizes timing
  52. What is line density?
    Spacing between sound beams
  53. What is range ambiguity?
    Inability to determine exact location of moving red blood celss with CW (continuous wave)
  54. What is pixel density?
    Number of pixels per inch
  55. What is spatial resolution?
    • High pixel density
    • Improved Image
    • Greater detail
  56. What are artifacts?
    Errors in imaging
  57. What is reverberation?
    Multiple equally-spaced echoes - resembles venetian blinds
  58. What is a Comet Tail?
    Ring down artifact appearing as solid hyperechoic line
  59. What is shadowing?
    Hypoechoic or anechoic region extending downward
  60. What is edge shadow?
    Hypoechoic region extending along edge of curved reflector
  61. What is enhancement?
    Hyperechoic region beneath tissue with low attentuation
  62. What is focal enhancement?
    Side to side region appears brighter than deeper tissue aka focal banding
  63. What is Mirror image?
    Artifact showing Deeper image redirected toward 2nd structure
  64. What is Crosstalk?
    Mirror image on Spectral Doppler display
  65. What is a speed error?
    Sound wave propagates through a medium other than that of soft tissue
  66. What is propagation speed error?
    Range error artifact or range ambiguity artifact
  67. What are side lobes?
    Created by a single crystal transducer or mechanical probe
  68. What are grating lobes?
    Created by Array transducer
  69. There are no known harmful bioeffects from U/S exams.

    T or F
  70. What are the units of Dynamic range?
  71. Slice thickness and Elevational resolution is

    Directly related
    Inversely related
    Not related
    Directly Related
  72. Which mode is the 1st grey scale imaging?

    A Mode
    B Mode
    M Mode
    B Mode
  73. Expiration increases or decreases venous flow in legs?
  74. The difference between received and transmitted frequencies is called

    Doppler Frequency
    Doppler Shift
    Power Doppler
    Doppler Shift
  75. Phased Array is reserved for Linear Transducer

    T or F
  76. What type of converter is used in U/S?

  77. Why does a gallstone have a shadow on U/S?

    Too much attenuation
    Too little attenuation
    No attenuation
    Too much attenuation
  78. What is a synonym of propagation speed error?
    Range ambiguity
  79. What does color Doppler provide information about?
    Range resolution
  80. What angle is best to scan carotid artery?
    60 degrees or less
  81. Power Doppler is also called
    Energy Mode
  82. Artifact is
    An error in imaging
  83. Which mode gives information about time?

    A Mode
    B Mode
    M Mode
    M Mode
  84. What are 2 controls on video monitor that the sonographer cannot change?
    Contrast and Brightness
  85. On inspiration the Diaphragm

    Stays the same
  86. Reynolds number determines laminar vs turbulent flow

    T or F
  87. Phasic flow is related to

    Cardiac contraction
  88. Spacial resolution improves with high or low line density?
    High line density
  89. What does ALARA mean?
    As Low As Reasonably Achieved
  90. What is dynamic range?
    The ratio of largest to smallest signal strength
  91. What are 5 requirements of contrast agents?
    • 1) Safe
    • 2) Metobolically inert
    • 3) Long lasting
    • 4) Strong reflector of U/S
    • 5) Small enough to pass through capillaries
  92. Harmonic frequency is ________ times fundemental frequency.