Ultrasound (lecture) Flashcards
KNOW: Ultrasound is utlized in out pt settings for msk disorders
Heat is used for chronic swelling
(tendinosis = chronic inflammation)
(tendinitits = acute inflammation)
(tendinopathy = some tendon disease)
Is transmision of heat (or any wave) transmitted better through dense objects or non-dense objects?
Dense (conserves the integrity of the wave?)
think blue whale can be heard for miles)
What do we put on the pt before doing ultrasound? Why?
Gel
Helps the heat be transmitted better
Ares of increased molecular density (compressions or refractions?)
compressions
Areas of decreased molecular density (compressions or refractions?)
Refractions
Once waves reach a change in tissue density what 3 things could happen?
Reflection
Refraction
Absorption
Know: Reflected waves can increase or decrease treatment wave intensity
Well less dense tissue absorb ultrasound waves well?
No! we said earlier that water absorbs heat waves well = increase density
Give some examples of tissues that dont absorb ultrasound well. Why don’t they absorb it well?
Muscle, blood, fat, muscle
because none of it is very dense (solids absorb the best)
So bone, tendon, cartilage, all absorb really well
tendinopathies / platnar fasicits are good for ultrasound because they’re tnedon which is dense and superficial
What absorbs ultrasound better, muscle or bone?
Bone (denser)
KNOW: Ultrasound machine goes back and forth between convex and concave to create waves (the frequency of waves is how fast it flips back and forth)
What is the frequncy range of an ultrasound machine?
1 million - 3.3 million
or
1-3.3MHz
this is talking about the # of waves per sacond
KNOW Effective radiating area = area that wave energy will be transmitted form the head of the ultrasound machine
Will effective raiding area be bigger or smaller than the sound head of the ultrasound machine?
Smaller!
It will be smaller because if you just put the head of the machine down on the skin that area thats radiated (in that singular spot) will be smaller than the head itself
What freqency is best for deeper tissue?
1 MHz (smaller frequency reaches deeper tissue better)
3.3 MGh frequency is for what kind of tissue?
Superficial tissue (think base in car = lower amount reaches deeper)
what frequency propages further - lower or higher
Lower
What creates faster warming - increased or decreased frequency?
Increased frequency (think 3.3 MGh)
What is intensity?
Wave amplitude (how high the waves are)
More energy w/ increased intensity
As intensity increases what happens to tissue warming?
It also icnreases
What should intensity be set on?
1.5