Chapter 2 Review Flashcards
What is the basic concept of ultrasound?
detect structures and measure distance
adjusts or amplifies the brightness of all of the pixels on the system monitor
overall gain
Is overall gain a pre or post processing function?
post
This control is used when the overall appearance of the image is too bright or too dark
overall gain
When adjusting the overall gain, a high setting introduces “noise” which decreases the _____ and _____ resolution.
contrast
spatial
As sound travels through tissue, there is a waveform amplitude reduction because of _______
attenuation
3 reasons for reduction in ultrasound energy through a tissue
absorption
scattering
reflection
Attenuation from lowest to highest .
water, fluid, fat, soft tissue, muscle, bone, and air
time gain compensation is also called
depth gain compensation
allows the adjustment of darker or brighter areas
TGC
the separation of structures perpendicular to the transmit beeam
lateral resolution
Lateral resolution is highest within ______
focal zone
If using multiple zones, you may see a decrease in _____
frame rate
The operating frequency relates directly to _______
thickness of the piezoelectric element
In ______ imaging, higher frequencies increase both aliasing and scatter artifacts
Doppler
allows adjustment of the amount of anatomy displayed in the image
image depth
the number of lines used in an image
line density
Narrowing sector width _____ frame rate
increases
Narrowing sector width, _____ lateral resolution
increases
the range of grays displayed in the B-mode image, M-mode tracing, or spectral Doppler tracing
Dynamic range
tint overlay to increase structure visualization
tint/colorize
temporal averaging of multiple sequential ultrasound images or frames
persistence/frame averaging
determines the number of frames used to create the final image
persistence
helps decrease the noise within an image because of the averaging of the data across multiple frames
persistence