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a.) Pulses of sound are used for ultrasound imaging.Choices A through C are discussed from the beginning of the tutorial through the section on resolution.
b.) Short, wider pulses improve resolution, or image quality.
c.) Ultrasound has a frequency greater than 20kHz.
d.) Intensity decreases as sound travels through the body.
You said:
b). Short, wider pulses improve resolution, or image quality.
Correct!
See: Resolution
2. Absorption, reflection and scattering are components of which one of the following?
a.) Spatial Pulse LengthAbsorption, reflection and scattering are discussed in the "Echoes" section.
b.) Piezoelectric Effect
c.) Attenuation
d.) Doppler Shift
You said:
c). Attenuation
Correct!
See: Echoes
3. Which of the following statements about sound is not true?
a.) Sound travels at the same speed, regardless of the medium.Study from the beginning of the tutorial through the review points that follow amplitude and intensity.
b.) Sound can not travel in a vacuum.
c.) The effect sound has on tissue is called the biological effect.
d.) Frequency is the only difference between audible sound and ultrasound.
You said:
a). Sound travels at the same speed, regardless of the medium.
Correct!
See: Types of sound
4. PRF stands for __________________.
a.) Preferred Reflection FrequencyStudy the "Types of Sound" section, specially pulsed ultrasound.
b.) Processed Recevied Frequency
c.) Pulsed Received Frequency
d.) Pulse Repetition Frequency
You said:
d). Pulse Repetition Frequency
Correct!
See: Types of sound
5. Fast Fourier Transform (FFT) is used to accomplish which task?
a.) Determine the frame rateReview the section on Doppler Ultrasond
b.) Determine the strength of the reflector
c.) Obtain blood flow information displayed on the spectral analysis
d.) Identify acoustical impedance
You said:
c). Obtain blood flow information displayed on the spectral analysis
Correct!
See: Doppler
6. Which of the following statements is false regarding today's imaging transducers?
a.) They contain multiple elements or crystals arranged in various patterns.Review the section on transducers.
b.) The elements must be made of piezoelectric materials.
c.) It is acceptable to sterilize imaging transducers using high heat.
d.) The elements are stationary and steering is accomplished by changing the firing patterns of the elements.
You said:
c). It is acceptable to sterilize imaging transducers using high heat.
Correct!
See: Transducers
7. The ability of a system to create images from very small structures and display those structures in their correct anatomical location is called _____________ resolution.
a.) TemporalReview the section on resolution.
b.) Axial
c.) Contrast
d.) Spatial
You said:
d). Spatial
Correct!
See: Resolution
8. Curved-linear transducers produce what shape of ultrasound image?
a.) Fan shaped or blunted sectorReview the section on transducers, specially "scanhead footprints".
b.) Rectangular
c.) Pie or sector shaped
d.) Rectangular top with sector sides
You said:
a). Fan shaped or blunted sector
Correct!
See: Transducers
9. Which of the following terms applies to the amount of energy contained in the beam?
a.) Spatial Pulse LengthChoices A through D are contained in different portions of the tutorial. The correct answer is discussed in the section on intensity.
b.) Attenuation
c.) Nyquist Limit
d.) Intensity
You said:
d). Intensity
Correct!
10. What happens when sound travels through tissue and then strikes a medium composed of a different density or stiffness?
a.) The Doppler shift occursReview the "Echoes" section
b.) The PRF decreases
c.) An echo or reflection is produced
d.) All the sound is absorbed
You said:
c). An echo or reflection is produced
Correct!
See: Echoes
11. Which of the following best describes the purpose of the backing material located inside the transducer housing?
a.) Determines the pulse repetition frequencyReview the section on transducers.
b.) Steers and focuses the beam
c.) Activates the elements
d.) Restricts the "ringing" ability of the elements
You said:
d). Restricts the "ringing" ability of the elements
Correct!
See: Transducers
12. What do we change to get different frequencies out of different transducers?
a.) The diameter of the elementReview the section on transducers
b.) The thickness of the element
c.) The number of elements
d.) The arrangement of the elements
You said:
b). The thickness of the element
Correct!
See: Transducers
13. In what type of scanhead does the element physically move?
a.) MechanicalReview the section on transducers
b.) Linear Phased
c.) Vector
d.) Convex
You said:
a). Mechanical
Correct!
See: Transducers
14. The change in the frequency of sound that results from motion between the sound source and the receiver is called the ____________________.
a.) Doppler equationReview the section on Doppler.
b.) Doppler effect
c.) Nyquist limit
d.) alias artifact.
You said:
d). alias artifact.
Incorrect!
See: Doppler
15. Which type of transducer is shown below? 
a.) Curved-linearReview the section on scanhead footprints.
b.) Linear
c.) Vector
d.) Phased
You said:
a). Curved-linear
Correct!
See: Transducers
16. Which one of the following does not describe CW Doppler?
a.) Can measure extremely high velocitiesReview the section on Doppler
b.) Uses two crystals inside the housing
c.) No Nyquist Limit
d.) Can identify the exact location of the velocity data
You said:
d). Can identify the exact location of the velocity data
Correct!
See: Doppler
17. What is the name of the plot or graph used to display components of blood flow?
a.) Color MapReview the section on Doppler
b.) Pixel Board
c.) Spectral Analysis
d.) Aliasing
You said:
a). Color Map
Incorrect!
See: Doppler
18. Which part of the system stores the image?
a.) PulserReview the section on instrumentation
b.) Display
c.) Beamformer
d.) Memory
You said:
d). Memory
Correct!
See: Instrumentation
19. What percentage of the sound beam is attenuated due to absorption?
a.) 50Review the "Echoes" section.
b.) 30
c.) 80
d.) 70
You said:
c). 80
Correct!
See: Echoes
20. Axial resolution artifacts are represented as structures that are ___________________.
a.) MissingReview the section on artifacts
b.) Improperly located
c.) Mirror Images
d.) Too bright
You said:
c). Mirror Images
Incorrect!
See: Resolution
21. The ability of a system to distinguish between very subtle differences in tissue signatures is called ____________ resolution.
a.) LongitudinalReview the section on resolution and instrumentation.
b.) Temporal
c.) Contrast
d.) Spatial
You said:
d). Spatial
Incorrect!
See: Resolution
22. Which one of the following statements does not describe color flow imaging?
a.) Doppler shifts are measured from multiple locations along multiple scan linesReview the section on Doppler and color Doppler.
b.) Velocity information is displayed as colors
c.) Color flow imaging uses pulsed techniques and is subject to aliasing
d.) Velocity information is obtained from one point at a predetermined depth
You said:
a). Doppler shifts are measured from multiple locations along multiple scan lines
Incorrect!
See: Color Flow Imaging
23. Which component of the instrumentation coordinates and processes all the signals going to and from the transducer?
a.) ReceiverReview the section on instrumentation.
b.) Beamformer
c.) Pulser
d.) Digital Scan Converter
You said:
a). Receiver
Incorrect!
See: Instrumentation
24. A high frequency (10 MHz or higher) transducer would usually be used to study which anatomical structure?
a.) ThyroidReview the "Echoes" section.
b.) Abdominal Aorta
c.) Fetal Abdomen
d.) Abdominal Mass
You said:
a). Thyroid
Correct!
See: Transducers
25. Which type of artifact can help the diagnostic process?
a.) Mirror ImageReview the section on artifacts.
b.) Refraction
c.) Shadowing
d.) Multipath
You said:
c). Shadowing
Correct!
See: Artifacts
26. The image below represents which type of display mode? 
a.) Motion modeReview the "Display" section.
b.) Brightness mode
c.) Amplitude mode
d.) B-mode
You said:
c). Amplitude mode
Incorrect!
See: Display
27. Which of the following statements regarding CW sound is false?
a.) Frequency, period, and wavelength are terms used to describe CW sound.Review the section on "Types of Sound".
b.) Continous wave sound has no velocity limitations.
c.) CW sound is used to create images in diagnostic ultrasound.
d.) The sound is on all the time.
You said:
c). CW sound is used to create images in diagnostic ultrasound.
Correct!
See: Types of sound
28. The z-axis of the beam is associated with which type of artifact?
a.) RefractionReview the section on artifacts.
b.) Multipath
c.) Acoustic Enhancement
d.) Section Thickness
You said:
d). Section Thickness
Correct!
See: Artifacts
29. Sound is mechancial in nature because _________________________________.
a.) Reflections are producedReview the "Principle of Sound" section.
b.) The sound travels in a straight line
c.) The molecules in the medium physically vibrate
d.) Sound can travel in a vacuum
You said:
c). The molecules in the medium physically vibrate
Correct!
See: Principles of Sound
30. The amount of time that the system is producing a pulse is called the __________________.
a.) Duty FactorReview Pulsed Ultrasound Terminology
b.) Pulse Duration
c.) Pulse Repetition Period
d.) Pulse Repetition Frequency
You said:
b). Pulse Duration
Incorrect!
See: Types of sound
