Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

E&I > Ultrasound > Flashcards

Ultrasound Flashcards

1
Q

Indications for Ultrasound

A 
Soft tissue shortening​
Pain control​
Repair of soft tissue injuries​
Dermal ulcers/Plantar warts​
Tendon injuries​
Resorption of calcium deposits​
Bone fractures​
Carpal tunnel syndrome​
Anti-inflammatory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Advantage

A

Primary advantage of US over other nonacoustic heating modalities is that TISSUES HIGH IN COLLAGEN (tendons, ligaments, fascia )AND OTHER DEEP TISSUES MAY be selectively heated to a therapeutic range without causing a significant tissue temperature increase in skin or fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

minimum desired tissue temp for thermal effects

A

104 F (40C)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is ultrasound

A

Ultrasound is an oscillating sound pressure wave with a frequency greater than the upper limit of the human hearing range, which is usually 20KHz​
​
Therapeutic US emits high frequency acoustic energy to produce thermal and non-thermal also called mechanical effects in tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Ultrasound waves cause

A

cellular vibration of molecules, increasing friction, causes increase in kinetic molecular energy within the tissues​

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Attenuation

A

absorption, reflection, and refraction of the wave

absorption- responsible for half of the loss of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Attentuation is greatest in what types of tissues

A

with high collagen content

tendon, cartilage, bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Absorption

A

conversion of mechanical energy into heat

high collagen tissue absorb the most soundwaves

as you increase protein content you increase absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Continuous US effect

A

thermal effects

increasing tissue temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pulsed US effect

A

non thermal (mechanical)
acoustic streaming
microstreaming
cavitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Clinical effects of thermal US

A 
Increased extensibility of collagen fibers​
tendons​
joint capsule​
Decreased joint stiffness
Reduction in muscle spasm​
Pain modulation​
Increased blood flow​
Increased metabolic rate​
Increased nerve conduction velocity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Primary advantage of US vs superficial heat

A

selective heating of tissues high in collage
US heats deeper
US heats smaller area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Stable Acoustic Cavitation

A

Formation, growth and pulsation of gas or vapor filled bubbles caused by US; bubbles oscillate in size do not burst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Microstreaming

A

Microscale eddying that takes place near any small, vibrating object​
Occurs around the gas bubbles set into oscillation by cavitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Acoustic microstreaming

A

Unidirectional movement of fluids along cell membrane boundaries​
Produces high viscous stresses​
Alters membrane structure & function​
Increased permeability to ionic influx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Effects from cavitation and microstreaming

A

Stim. of fibroblast activity … increases protein synthesis & tissue repair​
​
-Increased blood flow​
​
-bone healing & repair of non-union fractures

Inc in nitric oxide synthesis​
Inc in intracellular calcium levels​
Inc cell permeability

17
Q

Ultrasound Intensity

A

0 - 3 W/cm2​
​
The amt. of acoustic power per unit area of the sound head ​
​
Expressed in watts per centimeter squared ( W/cm2 )

18
Q

Lower Intensity & pulsed US used for

A

acute conditions/ thin tissue
produces nonthermal effects

if superficial bone- lower intensity

19
Q

High Intensity and continuous US used for

A

chronic conditions& thick tissue

20
Q

Ultrasound Frequency

A 
Determined by number of times crystal deformed/sec.​
2 most common utilized in U.S.​
1.0 MHz​
3.0 MHz​
Determines depth of penetration
21
Q

relationship between frequency and depth of penetration

A

inverse relationship
Penetrating depths:​
1.0 MHz Frequency: 2-5 cm​
3.0 MHz Frequency: 1-2 cm

Lower sound frequency penetrates deeper secondary to having a longer wavelength vs. higher sound frequency

Absorption rate increases with higher frequency

22
Q

Effective Radiating Area- ERA​

A

Total area on surface of transducer producing soundwave​
Ideally ERA should match size of transducer​
Treatment area should not exceed 2 times ERA

23
Q

Beam Non Uniformity Ratio - BNR​

A

The ratio of the spatial peak intensity to the spatial average intensity
The higher the piezoelectric quality of the transducer embedded in the sound head, the lower the BNR should be​
Can form hotspots that can cause tissue damage- move sound head around area throughout application to avoid this

24
Q

Continuous Delivery

A

100%
Uninterrupted emission of acoustic waves over time​
Intensity remains the same​
Induces a higher thermal effect in the tissue over time

25
Q

Pulsed Delivery

A

20%
Periodic interruption or pulsing of such waves​
Avg intensity reduced over time​
The longer the inter-pulse duration, the less thermal heating in the tissues

26
Q

US used for:

A 
Soft tissue shortening​
Pain control​
Dermal ulcers​
Surgical skin incisions​
Tendon and ligament injuries​
Bone fractures​
Carpal tunnel syndrome​
Phonophoresis
27
Q

Phonophoresis

A

Application of US in conjunction with a topical drug preparation as the US conduction medium​
​
Generally used in rehabilitation for treatment of tissue inflammation, such as tendonitis or bursitis​

US enhances delivery of drug through the skin, thereby delivering the drug for local and systemic effects​
​
Hydrocortizone/Dexamethasone (anti-inflammatory) and Lidocaine (analgesic)

28
Q

US increases __ of __ viathe process of __

A

US increases permeability of STRATUS CORNEUM via process of cavitation

29
Q

how US alters pore size

A

US alters pore size and creates more pores, drug is transported thru pores secondary to difference in concentration on either side of skin

30
Q

Recommended Tx Parameters for Phono

A

Frequency: 3MHz to optimize absorption through the skin​
​
Pulsed 20% Duty Cycle :to avoid heating of any inflammatory condition​
​
Intensity: 0.5 - 0.75 W/cm2​
​
Time:5- 10 minutes​
​
Be sure drug preparation used should transmit US effectively​
10% hydrocortizone more effective than 1% in relieving pain associated with tendonitis and bursitis

31
Q

US Contraindications

A 
Malignancy​
Pregnancy​
CNS tissue​
Joint cement​
Plastic components​
Pacemaker​
Thrombophlebitis​
Eyes and reproductive organs
32
Q

US Precautions

A

​Acute inflammation​
Epiphyseal plates​
Fractures​
Breast implants

33
Q

When does Patient start feeling warmth from US

A

When Tx goal is to increase tissue temp, pt should report feeling of “warmth” within 2-3 minutes​
Frequency of 1 MHz @ intensity of 1.5 - 2.0 W/cm2​
Frequency of 3 MHz@ intensity of 0.5 W/cm2

34
Q

Parameters for Soft Tissue Shortening

A 
Thermal
Duty Cycle 100%
Depth of problem 1-2 cm
Ultrasound frequency- 3 MHz
Ultrasound intensity- 0.5 W/cm2
Duration of Tx- 5-10 min/2 x ERA
OR 
Duty Cycle 100%
Depth of problem <5 cm
Ultrasound frequency- 1 MHz
Ultrasound intensity- 1.5 - 2 W/cm2
Duration of Tx- 5-10 min/2 x ERA
35
Q

Parameters for Delayed soft tissue healing or Prolonged inflammation

A 
Nonthermal
Duty Cycle 20%
Depth of problem 1-2 cm
Ultrasound frequency- 3 MHz
Ultrasound intensity- 0.5 -1 W/cm2
Duration of Tx- 5-10 min/2 x ERA
OR
Duty Cycle 20%
Depth of problem <5 cm
Ultrasound frequency- 1 MHz
Ultrasound intensity- 0.5 -1 W/cm2
Duration of Tx- 5-10 min/2 x ERA

E&I (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions