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WorksheetsChapter 16 & 17
Total questions: 68
Worksheet time: 56mins
List everything in the more shades chart:
(a)
Tissue Harmonics
results from nonlinear behavior of microbubble
weaker harmonic signal
stronger harmonic signal
created during reflection off of microbubble
A scale’s range of (a) measurement is 30 to 300 pounds- excellent for
measuring the weight of an adult, but not suitable for measuring the weight
of a bunch of grapes or an automobile.
What is dynamic range?
(a)
Weak signals (below 30 pounds) are below the system's
(a)
These strong signals (above 300 pounds) (a) the system.
the dynamic range of information (a) the more it is processed.
Contrast Harmonics
occurs as sound propagates in tissue
created during transmission in tissue
results from nonlinear behavior of microbubble
results from nonlinear behavior of transmitted sound beam
Rank the dynamic range of components from least to greatest with their
range. (receiver, display, scan converter, transducer, archive)
(a)
Higher MI: 0.1 to 1.0
some harmonics, resonance, nonlinear behavior, lower frequency sound, higher beam strength, bubble expands moderately
strongest harmonics, resonance, nonlinear behavior, lower frequency sound, higher beam strength, bubble expands moderately
no harmonics, backscatter, linear behavior, higher frequency sound, low beam strength, bubble expands very little
some harmonics, resonance, linear behavior, higher frequency sound, higher beam strength, bubble expands moderately
Archive
(a)
A method of reporting the extent to which a signal can vary and still be
accurately measured.
(a)
Scan Converter
(a)
Display
(a)
Receiver
(a)
Transducer
(a)
Can the sonographer adjust compression?
no, not adjustable
Is a technique that reduces the dynamic range of a signal without introducing
errors.
(a)
Compression using decibels are straightforward: decibels what?
divide or multiple
add or multiple
subtract or divide
Tissue Harmonics
stronger harmonic signal
created during reflection off of microbubble
occurs only when contrast agents are present and with MIs greater than 0.1
occurs as sound propagates in tissue
An alternative description of dynamic range is (a) .
Narrow dynamic range means ________, __________, _________.
(a)
Wide dynamic range means _____, _______, ________.
(a)
Low MI: less than 0.1
no harmonics, backscatter, nonlinear behavior, higher frequency sound, low beam strength, bubble expands very little
some harmonics, resonance, linear behavior, lower frequency sound, higher beam strength, bubble expands moderately
no harmonics, backscatter, linear behavior, higher frequency sound, low beam strength, bubble expands very little
strongest harmonics, bubble disruption, extreme nonlinear behavior, lowest frequency sound, highest beam strength, bubble expands greatly
List everything in the fewer shades chart:
(a)
The frequency of sound created by the transducer and transmitted into the
body.
(a)
Twice the fundamental frequency (also called (a) ).
Harmonic frequency sound waves arise from?
(a)
A ___________ of clinical studies are suboptimal because of sound beam
distortion.
small percentage
large but small percentage
large but significant percentage
small but significant percentage
Two characteristics of contrast agents are important:
the nature of the outer shell, and the gas that fills the microbubble
the color of the contrast agent and its temperature during injection
the nature of the outer shell, and the gas that doesn't fill the microbubble
the nature of the inner shell, and the color that fills the microbubble
Two forms of harmonics are important in diagnostic sonography:
(a)
Linear means proportional or symmetrical. Linear systems respond in an
even manner.
(a)
Nonlinear means irregular or disproportionate. A system is nonlinear when it
behaves unevenly.
(a)
Contrast Harmonics
created during transmission in tissue
stronger harmonic signal
weaker harmonic signal
results from nonlinear behavior of transmitted sound beam
As a sound wave travels in the body, a miniscule amount of energy is
converted from the fundamental frequency to the harmonic frequency.
(a)
A sound wave is a series of:
(a)
Tissue harmonics signals _______ depths; _______.
do not exist at extremely superficial depths, they don't develop deeper in the tissue
exist at extremely superficial depths, they develop deeper in the tissue
exist at extremely superficial depths, they do not develop deeper in the tissue
do not exist at extremely superficial depths, they develop deeper in the tissue
What are the units of Dynamic Range?
(a)
Tissue harmonics are _____ free and ____ distort.
(a)
Beams that are most likely to create harmonics are (a) likely to create artifacts.
Highest MI: greater than 1
some harmonics, bubble disruption, extreme nonlinear behavior, lowest frequency sound, higher beam strength, bubble expands greatly
strongest harmonics, bubble disruption, extreme nonlinear behavior, higher frequency, low beam strength, bubble expands greatly
no harmonics, backscatter, linear behavior, higher frequency sound, low beam strength, bubble expands very little
strongest harmonics, bubble disruption, extreme nonlinear behavior, lowest frequency sound, highest beam strength, bubble expands greatly
Is an imaging technique specifically designed to utilize harmonic
reflections, which are distortion free, while eliminating distorted
fundamental reflections.
(a)
What contains both fundamental and harmonic frequencies?
(a)
With pulse inversion harmonics, two consecutive ultrasound pulses are
transmitted down each scan line:
non-typical pulse, inverted copy that is out-of-phase with the first
non-typical pulse, inverted copy that is in-phase with the first
typical pulse, inverted copy that is in-phase with the first
Contrast Harmonics
created during transmission in tissue
weaker harmonic signal
created by nonlinear behavior in the speed of sound
created during reflection off of microbubble
The time required to create a frame is ______, the frame rate is ______, and
temporal resolution is ______.
(a)
Weaker first reflection ______ harmonics.
contains
Contrast Harmonics
occurs as sound propagates in tissue
weaker harmonic signal
occurs only when contrast agents are present and with MIs greater than 0.1
created during transmission in tissue
The stronger second reflection______ harmonics.
does not contain
contains
Two consecutive ultrasound pulses are sent down each scan line; the second
pulse is twice the strength of the first one.
(a)
Are gas bubbles encapsulated in a shell. They are injected in the circulation
(usually intravenously) or ingested (swallowed).
(a)
Have a different acoustic fingerprint than blood or tissue.
(a)
Contrast agents create strong reflections that actually “light up” ______,
_______, or other ______.
(a)
Higher mechanical index is
(a)
Contrast agents must meet the following five requirements:
safe, metabolically inert, not long lasting, weak reflector of ultrasound, small enough to pass through capillaries
safe, electrically charged, long lasting, brightly colored, easily visible under light microscopy
non-toxic, thermally conductive, biodegradable, able to dissolve in blood, radio-opaque
safe, metabolically inert, long lasting, strong reflector of ultrasound, small enough to pass through capillaries
Contrast harmonics are created (a) as energy is converted from the
fundamental frequency to the harmonic frequency.
When exposed to sound beams of adequate strength, contrast harmonics are
created because of the nonlinear changes in bubble size.
(a)
Harmonic production increases with
lower frequency sound, and weaker sound waves (substantial pressure variation)
higher frequency sound, and weaker sound waves (substantial pressure variation)
lower frequency sound, and stronger sound waves (substantial pressure variation)
higher frequency sound, and stronger sound waves (substantial pressure variation)
The amount of contrast harmonics produced may be estimated by a number
called the
(a)
Harmonic production increases with:
higher frequency sound, stronger sound waves
lower frequency sound, stronger sound waves
lower frequency sound, weak sound waves
higher frequency sound, weak sound waves
Low mechanical index is
(a)
Highest mechanical index is
(a)
Only the harmonic portions of the reflections remain while the fundamental
portions (a) .
Since fundamental portions of the reflections exhibit linear behavior, the two
inverse fundamental signals _______ and ______.
destructively interfere and complete each other
constructive interference and completes each other
destructively interfere and completely cancel each other out
constructive interference and completely cancel each other out
Tissue Harmonics
created during transmission in tissue
created during reflection off of microbubble
the nature of the outer shell
results from nonlinear behavior of microbubble
However, since harmonics exhibit nonlinear behavior, the harmonic portion
of the reflections are ______ and _____.
out-of-phase and, interfere constructively
in-phase, deconstructive interference
out-of-phase, deconstructive interference
The remaining harmonic reflections form an image with (a) .
Tissue Harmonics
stronger harmonic signal
created during reflection off of microbubble
results from nonlinear behavior of transmitted sound beam
results from nonlinear behavior of microbubble
