Foundation quizzes 5-10

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Foundation quizzes 5-10
2012-10-06 15:24:21
foundation quizzes 10

foundation quizzes 5-10
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  1. if the boundary of an interface is smooth and larger than the wavelength of the ultrasound it is termed..
  2. the minimum reflector seperation along the sound path required to produce seperate echoes is termed...
    axial resolution
  3. non-specular reflectors
    may be imaged with oblique incidence without artifacts
  4. where in the imaging field is the lateral resoution the best
  5. the potential for heating the tissue while imaging is displayed as...
    thermal index (TI)
  6. the transfer of sound energy through the medium is termed..
  7. frequency of ultrasound is Greater or Less than 20Hz
    frequency less than 20Hz
  8. What has the slowest propagation speed?
  9. the conversion of mechanical energy to electrical energy is also known as...
    piezoelectric effect
  10. what is the effect of higher frequencies on attenuation and penetration?
    more attenuation, less penetration
  11. increasing the dynamic range of the pulse-echo ultrasound system...
    creates a wider range of displayed gray levels
  12. when a sonographer changes the gain control, what system component is responsible for the adjustment?
  13. Time gain compesation (TGC) adjusts the image brightness to compensate for..
  14. what is a harmonic frequency of 3.5MHz
  15. what type of imaging is displayed on this image?
    a mode
  16. what adjustments can be made to increase the frame rate of this exam?
    narrow the focal zone
  17. an advantage of sequenced linear array transducers is
    best image resolution of all transducer types
  18. an advantage of curved array transducers is...
    relatively easy intercostal transducer manipulation
  19. phased array transducers...
    use all of the transducer crystals to produce one scan line
  20. a sonographer can increase frame rate by..
    decreasing the image width
  21. what is the scan converter function that deterimines the assignment of echos to predetermined gray scale levels?
  22. a digital picture element is a..
  23. preprocessing functions must be performed...
    before the image is frozen and stored
  24. to magnify the image and improve its resolution the sonographer should use...
    write-magnification before storing in memory
  25. when performing a vascular imaging exam you would like thre to be less shades of gray, you should...
    decrease dynamic range (low dynamic range, high scale of contrast)