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Passive Care- JS > Ultrasound > Flashcards

Flashcards in Ultrasound Deck (36)
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1
Q

what type of healing modality is ultrasound

A

deep heating

2
Q

what is the most common deep heating modality

A

ultrasound

3
Q

what is the most common heating modality

A

moist hot packs

4
Q

2nd most common heating modality

A

ultrasound

5
Q

what does the electrical current pass through

A

crystal 2-3 mm thick

6
Q

Duty cycle of 100% means what

A

continuous

results in tissue heating

7
Q

What is the reverse piezoelectric effect

A

mechanical deformation of crystal causes an electrical current to form

8
Q

What is near field

A

treatment area-fresnel zone

9
Q

what is far field

A

fraunhofer zone

10
Q

what is spatial peak intensity

A

Isp
peak intensity
watts per cm2

11
Q

what is spatial average intensity

A

Isp * duty cycle

12
Q

ERA (effective radiating area)

A

area of the sound head that produces sound energy

13
Q

BNR (beam nonuniformity ratio)

A

ultrasound beams not uniform across US head

amount of variability of the beam

14
Q

What is the ideal BNR

A

1:1

15
Q

What is an accepted BNR

A

2:1-8:1

16
Q

Peak area of the maximum beam nonuniformity ratio (PAMBNR)

A

the area of the sound head covered by the peak intensity

17
Q

Larger PAMBNR means what

A

less uniform heating

18
Q

What is an ideal conducting media for US

A

US gel and gel pads

19
Q

Indirect ultrasound is

A

ultrasound done underwater in a plastic bucket

keep sound head parallel 0.5-3.0 cm

20
Q

Amplitude of soundwave

A

more watts=more heating NOT GREATER PENETRATION

21
Q

frequency of US

A

1-3 MHz

22
Q

Does high or low frequency absorb more rapidly

A

high (3MHz)

superficial tissue

23
Q

does high or low frequency absorb slower

A

low (1MHz)

deep tissue

24
Q

higher density leads to _______ absorption rate

A

higher

25
Q

Effects of US

A

Inc extensibility
Inc blood flow
Inc healing
Dec stiffness/spasm

26
Q

Non thermal effects

A

pulse US- alters cellular activity for injury repair

27
Q

What is stable cavitation

A

rhythmic expansion and contraction of bubbles during repeated pressure changes over many acoustic cycles

28
Q

What is unstable cavitation

A

collapse of gas bubbles which may cause tissue damange (low frequency high intensity US)

29
Q

Contraindications of US (12)

A
malignancy
hemmorrhage
ischemia
thrombus
infection
gonads
eye
pelvic/lumbar/abs of preggo
spinal cord post laminectomy
plastic and cemented implants
electronic implants
unknown etiology
30
Q

What type of implants are okay for US

A

metal

31
Q

Where should you avoid with US (2)

A

bony prominences

epiphyseal plate

32
Q

What size is the treatment area for US

A

2-3x the size of ERA

33
Q

How long is treatment with US

A

5-8 min

NEVER LONGER THAN 15 MIN

34
Q

What is phonophoresis

A

sonophoresis

uses sound energy to drive medication into tissue

35
Q

What is LIP US

A

low intensity pulsed US

stimulation of fracture healing

36
Q

what is NCLF US

A

noncontact low frequency US

wound cleaning and debridment