Ultrasound

Question 1

Piezoelectric Crystals

Answer 1

Quartz, ceramic, or polymer composition that contain a matrix of polarized molecules

1) Change shape in response to electrical current
2) respond to mechanical stress by generating an electric current

Question 2

Piezoelectric Effect

Answer 2

The ability to generate an electric current in response to mechanical stress

Question 3

Resonant frequency

Answer 3

The rate at which piezoelectric crystals vibrate when subjected to alternating current

Question 4

Doppler effect

Answer 4

Frequency increases as a moving object gets closer due to “stacking up” of wave fronts

Frequency decreases as it moves away

As blood cells flow to or away from an ultrasound signal, reflected waves are either compressed or expanded- giving us velocity

Question 5

Sound

Answer 5

The compression of air in a medium caused by a vibration

Question 6

5 characteristics of sound waves

Answer 6

Amplitude
Wavelength
Frequency
Cycle
Velocity?

Question 7

Echogenicity

Answer 7

Ability of a structure to reflect ultrasound waves and bounce echoes

Question 8

Hyperechoic

Answer 8

Structure appears brighter- strong signal reflection (white)

Bone, fascia

Question 9

Hypoechoic/anechoic

Answer 9

Structure appears darker or black, no or fewer echoes are produces from the structure- simple fluid filled spaces

Question 10

Isoechoic

Answer 10

Structure exhibits the same brightness as the surrounding structure