Ultrasound Terminology

Question 0

Acoustic impedence

Answer 0

Density of tissues times the speed of sound in tissue. Sound is reflected back when it reaches the border between two structures with different acoustic impedance

Question 1

Acoustic enhancement

Answer 1

An increase in echoes distal to fluid when sound travels through a fluid-filled structure

Question 2

Amplitude

Answer 2

Strength or height of a wave

Measured in decibels

Question 3

Anechoic

Answer 3

Without echoes, echo-free (but not necessarily cystic)

Question 4

Attenuation

Answer 4

Weakening of sound as it travels through tissue, caused by scatter, absorption and reflection

Question 5

Complex

Answer 5

A structure that contains both fluid and solid components

Question 6

Cycle

Answer 6

The frequency at which an ultrasound transducer crystal vibrates
per second;
One complete wave or one area of compressed molecules and one area of less dense molecules

Question 7

Cyst

Answer 7

Fluid filled structure that has well-defined borders, transmits sound well and displays acoustic enhancement

Question 8

Cystic

Answer 8

Used to describe a fluid-filled structure ; can refer to normal structures that are fluid filled (ex. Gal bladder)

Question 9

Decibel

Answer 9

Intensity of the amplitude of a sound wave;

Ratio of acoustic power

Question 10

Duplex

Answer 10

Simultaneous display of B-scan image and Doppler waveform

Question 11

Triplex

Answer 11

Simultaneous display of B-scan, Doppler waveform and color Doppler

Question 12

Dynamic range

Answer 12

The range of echo intensity (shades of gray) that the system can display

Question 13

Echogenic

Answer 13

A structure that produces echoes;

Each structure in the body has a particular pattern of echoes it produces

Question 14

Frequency

Answer 14

Number of times a sound wave is repeated per second;
Number of cycles that pass a certain point in tissue in one second

(2.25mHz - 20mHz)

Question 15

Gain

Answer 15

Regulates the degree of echo amplification

Question 16

Hertz (Hz)

Answer 16

Standard unit of frequency equal to 1 cycle per second

Question 17

Heterogenous

Answer 17

Mixed composition;

Echo pattern is not uniform

Question 18

Homogenous

Answer 18

Uniform composition of body tissues or structures

Question 19

Hyperechoic

Answer 19

More echoes, more echogenic (whiter)

Question 20

Hypoechoic

Answer 20

Fewer echoes, less echogenic

Question 21

Interface

Answer 21

Strong echoes marking the border between structures, caused by the difference in sound impedance between the 2 structures

Question 22

Isoechoic

Answer 22

Of the same echogenicity as a neighboring structure

Question 23

Piezoelectric effect

Answer 23

Effect caused by crystals changing in shape when an electric current in applied or when mechanically stressed;
Allows an electrical impulse to generate sound and sound to generate an electrical impulse

Question 24

Power

Answer 24

Quantity of energy generated by a transducer Measured in watts

Question 25

Resolution Two types?

Answer 25

The ability of the ultrasound equipment to distinguish between two structures -lateral resolution- distinguishes between 2 structures side by side at the same depth •• -axial resolution- distinguishes two structures along the axis of the sound beam (at different depths in the same spot)• •

Question 26

Reverberation

Answer 26

An artifact resulting from strong echoes returning from a large surface or interface

Question 27

Ring down

Answer 27

Extreme form of reverberation which is a long series of echoes and reverberations seen from a strong interface

Question 28

Shadowing

Answer 28

An artifact created when an object transmits sound completely so that no echoes return, such as gallstones or bone sound travels over 4000m/sec and continues without echoes returning. Structures behind these objects will not be seen

Question 29

Sonologist

Answer 29

A physician trained in and who specializes in interpreting sonographic images

Question 30

Sonogram

Answer 30

An image or "picture" produced with sound

Question 31

Sonographer

Answer 31

A allied health professional that performs diagnostic ultrasound imaging

Question 32

Sonolucent

Answer 32

Without echoes, but not necessarily cystic | Hypoechoic

Question 33

Texture

Answer 33

The echo pattern of an organ

Question 34

TGC, DGC

Answer 34

Control that allows operator to compensate for the attenuation if sound as it travels through tissue

Question 35

Transducer

Answer 35

A device capable of converting energy from one form into another

Question 36

Velocity

Answer 36

Speed of sound, depending of structure density or tissue

Question 37

What is the average speed of sound in [human soft tissue] the body?

Answer 37

1540 m/sec

Question 38

Wavelength

Answer 38

The distance a wave travels in 1 sec; | Higher the frequency = shorter the wavelength, shorter the distance it travels