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  • 1. 
    The frequency closest to the lower limit of US is
    • A. 

      19,000 kHz

    • B. 

      10,000 MHz

    • C. 

      20,000 msec

    • D. 

      15,000 Hz


  • 2. 
    Put in decreasing order
    • A. 

      Deca, deci, centi, micro

    • B. 

      Deci, deca, centi, micro

    • C. 

      Micro, centi, deca, deci

    • D. 

      Centi, micro, deci, deca


  • 3. 
    Which of the following is determined by the source and the medium?
    • A. 

      Frequency

    • B. 

      Period

    • C. 

      Propagation speed

    • D. 

      Range resolution


  • 4. 
    As a result of _____________ the propagation sped increases
    • A. 

      Increasing stiffness and increasing density

    • B. 

      Increasing stiffness and increasing elasticity

    • C. 

      Decreasing compressibility and decreasing density

    • D. 

      Decreasing stiffness and decreasing density


  • 5. 
    Put in decreasing order of propagation speed.
    • A. 

      Gas, liquid and solid

    • B. 

      Solid liquid and gas

    • C. 

      Liquid gas solid


  • 6. 
    If the frequency of US is increased from 0.77 MHz to 1.54 MHz, what happends to the wavelength?
    • A. 

      Doubles

    • B. 

      Halved

    • C. 

      Remain the same

    • D. 

      4 times greater


  • 7. 
    If the intensity of a sound beam remains unchanged while the beam area is reduced in half, what has happend to the power?
    • A. 

      Quadrupled

    • B. 

      Doubled

    • C. 

      Halved

    • D. 

      Unchanged


  • 8. 
    What is the minimum value of the duty factor?
    • A. 

      10.0

    • B. 

      1%

    • C. 

      1.0

    • D. 

      0.0%


  • 9. 
    If a 5MHz sound wave is traveling in the tissues listed below, which will have the longest wavelength?
    • A. 

      Fat

    • B. 

      Air

    • C. 

      Muscle

    • D. 

      Bone


  • 10. 
    As the impedances (z (rayls) = density (kg/m^3) x prop. speed (m/s) or acoustic resistance to sound traveling in a medium, becomes vastly different, the
    • A. 

      Reflection increases

    • B. 

      Transmission increases

    • C. 

      Refraction increases

    • D. 

      Absorption increases


  • 11. 
    With normal incidence, what factors affect refraction of US?
    • A. 

      Propagation speeds

    • B. 

      Frequencies

    • C. 

      Attenuation coefficients

    • D. 

      None of the above


  • 12. 
    The most likely amount of reflection at a boundary between soft tissue is:
    • A. 

      1%

    • B. 

      22%

    • C. 

      34%

    • D. 

      99%


  • 13. 
    How many cm are 60 millimeters
    • A. 

      600

    • B. 

      6

    • C. 

      0.6

    • D. 

      0.006


  • 14. 
    How is range ambiguity artifact eliminated?
    • A. 

      Lower the PRF

    • B. 

      Raise the PRF

    • C. 

      Increase the gain

    • D. 

      Use a lower frequency transducer


  • 15. 
    Under which of the following conditions is lateral resolution improved?
    • A. 

      Decreased beam diameter

    • B. 

      Decreased pulse duration

    • C. 

      Decreased imaging depth

    • D. 

      Decreased pixel size

    • E. 

      Decreased spatial pulse length


  • 16. 
    Which transducer would be best to image superficial structures?
    • A. 

      Small diameter, high frequency

    • B. 

      Small diameter, low frequency

    • C. 

      Large diameter, high frequency

    • D. 

      Large diameter, low frequency


  • 17. 
    If the frame rate increases and the lines per frame is unchanged, what else must happen?
    • A. 

      US speed increases

    • B. 

      Frequency increases

    • C. 

      Depth increases

    • D. 

      Depth decreases


  • 18. 
    TRUE OR FALSEA system which was working well now does not display clear images in the far field.  This may be a problem with the monitor.
    • A. 

      True

    • B. 

      False


  • 19. 
    If the output of an US machine is calibrated in dB and the output is increased by 20 dB, the beam intensity is increased
    • A. 

      100 times

    • B. 

      1,000,000 times

    • C. 

      20 times

    • D. 

      10 times


  • 20. 
    Which of the following will result in the greatest number of shades of grapy in a digital image display?
    • A. 

      Large pixels with many bits/pixel

    • B. 

      Small pixels with few bits/pixel

    • C. 

      Many TV lines per frame

    • D. 

      High contrast

    • E. 

      Narrow dynamic range


  • 21. 
    With good images on the CRT but not on the strip chart recorder, one should
    • A. 

      Increase the gain

    • B. 

      Check the scan head

    • C. 

      Check the same converter

    • D. 

      Adjust the recorder


  • 22. 
    Compression is used to
    • A. 

      Decrease the amplitude

    • B. 

      Decrease the range of amplitudes

    • C. 

      Decrease the range of frequencies


  • 23. 
    In which of these biologic tissues will sound waves propagate most quickly?
    • A. 

      Tendon

    • B. 

      Blood

    • C. 

      Lung

    • D. 

      Fat

    • E. 

      Amniotic fluid


  • 24. 
    All of the following statements regarding in-vitro bioeffects are true EXCEPT?
    • A. 

      In vitro bioeffects conclusions are clinically relevant

    • B. 

      In vitro bioeffects are always real

    • C. 

      In vitro bioeffects are vey important

    • D. 

      In vitro bioeffects may not be applicable to clinical settings


  • 25. 
    Which of the following improves signal to noise ratio
    • A. 

      Dynamic range

    • B. 

      Frame averaging

    • C. 

      Gray scale

    • D. 

      Edge enhancement

    • E. 

      Receiver gain


  • 26. 
    Under which circumstances is cavitation most likely to occur
    • A. 

      High frequency and low power

    • B. 

      High intensity and high frequency

    • C. 

      Low intensity and low frequency

    • D. 

      Low frequency and high signal amplitude


  • 27. 
    What is displayed on the y-axis of an m-mode image?
    • A. 

      Time

    • B. 

      Time of flight

    • C. 

      Echo intensity

    • D. 

      Red blood cell velocity


  • 28. 
    An amplifier of an ultrasound system increases the voltage of a signal from 0.0001 to 0.1 volt.  What is the amplification
    • A. 

      60 dB

    • B. 

      30 dB

    • C. 

      1,000 dB

    • D. 

      90 dB


  • 29. 
    The impedances of tissue is 3 x 10^5 rayls and for the PZT crystal is 6 x 10^6 rayls.  What is the best impedance for the matching layer?
    • A. 

      36 x 10^5

    • B. 

      3,600

    • C. 

      10,000

    • D. 

      9.5 x 10 ^5

    • E. 

      9 x 10^4


  • 30. 
    Put in increasing order of propagation speed
    • A. 

      Air bone water

    • B. 

      Bone water air

    • C. 

      Air water bone

    • D. 

      Water air bone

    • E. 

      Bone air water


  • 31. 
    What is propagation speed determined by
    • A. 

      Wavelength

    • B. 

      Intensity and density

    • C. 

      Amplitude

    • D. 

      Density and elasticity

    • E. 

      Density and amplitude


  • 32. 
    If 300,000 cycles occur in a second, what is the wave's frequency?
    • A. 

      3 MHz

    • B. 

      30 kHz

    • C. 

      300 MHz

    • D. 

      3 kHz

    • E. 

      0.3 MHz


  • 33. 
    All of the following will improve temporal resolution EXCEPT
    • A. 

      Increased line density

    • B. 

      Single rather than multi focus

    • C. 

      Higher frame rate

    • D. 

      Shallower depth of view

    • E. 

      Slower speed of sound in a medium


  • 34. 
    What component of a transducer changes electrical to mechanical and mechanical back to electrical engergy?
    • A. 

      PZT

    • B. 

      Transducer


  • 35. 
    What are typical clinical Doppler frequencies
    • A. 

      1 - 10,000 Hz

    • B. 

      1 - 10 MHz

    • C. 

      2 - 1,000 kHz

    • D. 

      40 - 45 kHz


  • 36. 
    What is the actual time that an US machine is creating a pulse?
    • A. 

      Duty factor

    • B. 

      Period

    • C. 

      Pulse period

    • D. 

      Pulse duration


  • 37. 
    What is the significance of gray scale variation in the spectrum of a pulssed wave Doppler display?
    • A. 

      It represents the number of red blood cells creating the reflection

    • B. 

      It represents the velocity of red blood cells

    • C. 

      It represents the speed of red blood cells

    • D. 

      It represents the convergence of red blood cell lamina

    • E. 

      It determines the enseble length


  • 38. 
    What is the production of deformation from voltage called?
    • A. 

      Piezoelectricity

    • B. 

      Impedance

    • C. 

      Cogeneration

    • D. 

      Flux


  • 39. 
    What is the elimination of voltages that do not exceed a certain level?
    • A. 

      Amplification

    • B. 

      Decompensation

    • C. 

      Reject

    • D. 

      Demodulation


  • 40. 
    How many data bits are needed to represent 46 gray shades?
    • A. 

      46

    • B. 

      5

    • C. 

      6

    • D. 

      8


  • 41. 
    Which of the following is associated with cavitation?
    • A. 

      Thermal index

    • B. 

      Snell's Law

    • C. 

      Avagadro's Number

    • D. 

      Mechanical index


  • 42. 
    All of the following are true of normal cavitation EXCEPT:
    • A. 

      Harmful bioeffects are commonly observed

    • B. 

      It is also known as inertial cavitation

    • C. 

      Only a 10% increase in pressure is needed to convert to this from stable cavitation

    • D. 

      Temperatures in the thousands of degreesare created

    • E. 

      It is consistent with shock waves


  • 43. 
    The packet size in color Doppler refers to the number of :
    • A. 

      Pulses per second

    • B. 

      Sample volumes per scan line

    • C. 

      Scan lines per unit area

    • D. 

      Pulse - listen cycles per acoustic scan line

    • E. 

      Pulses required to create one frame


  • 44. 
    A commonly used process for determining direction in a Doppler instrument is
    • A. 

      Zero crossing detection

    • B. 

      Autocorrelation

    • C. 

      Phase quadrature detection

    • D. 

      Range gating

    • E. 

      Spectral analysis


  • 45. 
    What is the maximum velocity limit for a 3 MHz CW Doppler unit operating at a depth of 4cm?
    • A. 

      40 cm/s

    • B. 

      200 cm/s

    • C. 

      2.5 m/s

    • D. 

      4 m/s

    • E. 

      None of the above


  • 46. 
    What method is used to steer the color beam with a linear array transducer?
    • A. 

      Mechanical

    • B. 

      Electronic time delays

    • C. 

      Electronic voltage variation

    • D. 

      Apodization

    • E. 

      The color beam cannot be steered with a linear array transducer


  • 47. 
    Increasing the wall filter during Doppler sampling will:
    • A. 

      Increase visibility of low velocity signals

    • B. 

      Increase spectral broadening

    • C. 

      Decrease bandwidth

    • D. 

      Reduce display of low frequency shifts

    • E. 

      Reduce aliasing


  • 48. 
    What would be the most likely result from increasing the transmit frequecy of the color Doppler?
    • A. 

      Improve sensitivity to slow flow

    • B. 

      Improved penetration for imaging flow in deep tissues

    • C. 

      Reduced flash artifact obscuring small vessel flow

    • D. 

      Reduced color Doppler aliasing

    • E. 

      Improve visibility of complex flow hemodynamics


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