UltraSound

Question 1

What is the typical therapeutic range utilized for Ultrasound?

Answer 1

1 or 3 MHZ

Question 2

An alternating current is passed through a crystal causing it to vibrate and produce what?

Answer 2

High-Frequency sound waves

Question 3

Effective Radiating Area (ERA) is what?

Answer 3

The area of the crystal that actually produces sound waves.

*It produces more than 5% of the energy at 5mm from the transducer face.

Question 4

Beam Profile

Answer 4

Multiple waves emerge from the head.

*Energy diverges as it moves away from the source and is uniform close to the head called “Near Zone”

Question 5

1 MHz output penetrates how deep?

Answer 5

5-7cm

Question 6

3 MH Output penetrates how deep?

Answer 6

1-2cm

Question 7

Heating rate and magnitude is based on what?

Answer 7

• Duty Cycle
• Output Frequency
• Intensity
• Target Tissue
• Size of Treatment area

Question 8

What are the Thermal effects of Ultrasound?

Answer 8

Increased sensory nerve conduction velocity
-increased motor nerve conduction velocity
-increased extensibilityof collagen rich fibers
increased Blood flow, vascular permeability, increases macrophage activity, Reduces muscle spasm

Question 9

For mild inflammation and to Accelerate metabolism, you should increase tissue by how many degrees?

Answer 9

1 degree celsius

Question 10

To help decrease muscle spasms, what temperature should be acquired?

Answer 10

Mild temperature, increasing the tissue 2-3 degrees celsius

Question 11

For nonthermal application, the pulsed output should be?

Answer 11

20-25% duty cycle

Question 12

Continuos Output, a 100% duty cycle creates what effect?

Answer 12

A Thermal effect

Question 13

Accustic Streaming is what?

Answer 13

It is ultrasound that causes interstitial fluids to flow, striking cell membranes, producing EDDY Currents, which displace ions and molecules. This altars cell membrane permeability and Cellular function.

Question 14

The vibrating crystal is known as what effect?

Answer 14

Electropiezo Effect!

Question 15

ERA (Effective Radiating Area) is always smaller than the what?

Answer 15

The transducer face

Question 16

Is energy more concentrated on the outside or near the center for ultrasound?

Answer 16

Near the center.

Question 17

Spatial Peak Intensity

Answer 17

The spatial peak intensity is the point in the sound field with maximum intensity. Becomes less consistent farther away from the head.

Question 18

Spatial Average Intensity

Answer 18

Describes the energy per unit of area, AKA W/cm2

*15 watts over 10cm2 ERA = 1.5 W/cm2

Question 19

This describes the amount of variation in the beam and is the ration between spatial Peak intensity (SPI) and spatial Average intensity?

Answer 19

Beam Nonuniformity Ratio
*BNR = SPI / SAI
*Perfect beam = 1:1
Minimally acceptable = 8:1
*most units are 5:1 or 6:1

Question 20

What setting is needed to provide a thermal effect for ultrasound?

Answer 20

Continuous, based on output intensity and treatment duration.
*100% duty cycle

Question 21

A patient has swelling in the ankle but Ultrasound is still administered, what setting is used?

Answer 21

A pulsed setting to produce Non-thermal effects!

*Usually 20-25% duty cycle

Question 22

The following effects are due to what?

• increased cell membrane permeability
• Alters cell membrane diffusion rate
• increased histamine release
• Mast cell degranulation and increased rate of protein synthesis

Answer 22

Acoustical Streaming

Question 23

Thermal effects on cellular response from US include?

Answer 23

Increased cell metabolism and rate of inflammation

Question 24

The thermal effect from US may lead to an earlier onset of proliferation, increase macrophage activity, lead leukocytes to bind to damaged endothelial cells, and increase cell division, helping through which phase?

Answer 24

Inflammation

Question 25

What frequency settings for US should you use to cause a release of performed fibroblast?

Answer 25

1 MHz Output

Question 26

To help increase synthesis and secretion of fibroblast precursors, especially in areas of high collagen concentration (shallow)?

Answer 26

3 MHz

Question 27

Ultrasound will have what effect on blood and fluid dynamics?

Answer 27

May increase blood flow for 45 minutes, creating a thermal effect, decrease vascular tone, and histamine release.

Question 28

What are the Direct Pain Reduction effects of US?

Answer 28

Increase nerve cell sodium permeability, alters nerve function, and increases pain threshold.

Question 29

What are the Indirect Pain Reduction effects of US?

Answer 29

Increase blood flow, increase capillary permeability, increase oxygen delivery, and decrease muscle spasm.

Question 30

What is reduced secondary to the following effects of US:

• Decreased pain
• Altered nerve conduction
• Increased temperature
• and muscle relaxation

Answer 30

Muscle Spasms

Question 31

If you are using Ultrasound to increase tissue elasticity, when should you stretch the body part?

Answer 31

During the application or immediately after because the stretching window only lasts 3 minutes following treatment.

Question 32

You are treating a tendon impairment using Ultrasound with no swelling. To assist with tendon healing, what US application is appropriate?

Answer 32

Continuous US to increase tensile strength and collagen deposition.

Question 33

Your patient Eric Marie gave himself a Skin Ulcer. What settings would you use for US to treat this guy?

Answer 33

Cover the Skin Ulcer wound with an occlusive dressing and use 3 MHz, low intensity pulsed output.

Question 34

You have just sustained a fracture yesterday and your PT wants to perform Ultrasound on that area. Is this contraindicated?

Answer 34

Yes if it is a general US unit. You need a specialized US unit for fracture healing that produces Low-intensity pulsed output.

Question 35

To help with tissue elongation and scar tissue reduction, what temperature should be utilized?

Answer 35

Vigorous temperature, heating the tissue by 3-4 degrees celsius.