Flashcards in Harmonics TEST Deck (22):
Harmonic imaging and contrast agents increase....
harmonics gets rid of what color?
some of the gray
How is the image created with harmonics?
by processing reflections that are twice the fundamental frequency
(aka incident, fundamental, central, transmitted main, resonant frequency)
arises from ***non linear behavior*** a multiple of two of the original frequency
what are the two kinds of harmonic imaging?
When is harmonics created?
What is THI or CHI
Tissue Harmonic Imaging
Contrast Harmonic imaging
What has made harmonics possible?
broadband technology has made this possible
increases signal to noise ratio
least likely to create artifacts
How does harmonics affect spatial resolution?
it increases detail or spatial resolution
decreases reverberation artifact
When you put the harmonics on is deep scanning the best?
no because the frequency is now higher and penetration is limited
If you have fundamental imaging what is the frequency?
finish slide 9
The fundamental frequency is filtered and the second harmonic echoes are passed. How does this affect lateral resolution and grating lobe artifacts?
narrower beam improves lateral resolution
eliminates grating lobe artifacts
What does harmonics do to the signal to noise ratio?
increases the signal to noise ratio
What three things increases the signal to noise ratio?
persistence (frame average)
What does tissue harmonics enhance?
Tissue harmonics helps with shadowing and ....
what are the contrast agent requirements?
With contrast harmonics what kind of index do you use?
set so you don't burst the contrast bubbles and cause tissue damage
Is contrast harmonics linear or non linear?
MI is related to the likelihood of bioeffects what are these scales?
If you have a lower mechanical index what happens to harmonics?
in contrast harmonics
What is a conventional system?
no bells and whistles like harmonics and such