Ch. 1 Foundations of Sonography (2)

Question 1

Acoustics is the study of _______, _______, and _________sound waves.

Answer 1

Generating, propagating, and receiving

Question 2

Ultrasound is defined as sound frequencies beyond the upper limits of human hearing, that is, greater than _________.

Answer 2

20 Kilohertz

Question 3

Name the three pioneers who made a significant contribution to ultrasound

Answer 3

John Wild, Dr. Hellmuth Hertz, Inge Elder

Question 4

The terms ________, __________, and __________ have all been used to describe an imaging technique by which soft tissue structures of the body are visualized by recording the returning reflection of ultrasonic waves directed into the body.

Answer 4

Diagnostic Medical ultrasound, ultrasound, and ultrasonography

Question 5

The term that applies to the ultrasound evaluation of cardiac structures is ________.

Answer 5

Echocardiography

Question 6

One who performs ultrasound studies and gathers data under the direct or indirect dupervision of a physician is a __________

Answer 6

Sonographer

Question 7

The qualities of a good sonographer are , , ,

Answer 7

1. Intellectual curiosity
2. Perseverance
3. Ability to conceptualize two dimensional images into a three dimensional format
4. Quick and analytical mind
5. Technical amplitude
6. Good physical health
7. Independence and initiative
8. Emotional stability
9. Communication skills
10. Dedication

Question 8

As the ceramic element vibrates, it periodically presses against and pulls away from the adjacent medium with resultant particle __________ and ____________in the meduim

Answer 8

Compression and rarefraction

Question 9

A transducer converts_________ energy into ___________ energy.

Answer 9

Electrical into mechanical

Question 10

A propagation of energy that moves back and forth or vibrates at a steady rate is a __________

Answer 10

Wave

Question 11

The time required to produce each cycle depends of the _________of the transducer

Answer 11

Frequency

Question 12

The distance between two peaks over a period of time is the _________

Answer 12

Wavelength

Question 13

Wavelength is inversely related to frequency, which means that the higher the frequency, the _________ the wavelength

Answer 13

Shorter

Question 14

As frequencies become higher, the pulse duration ________, yielding a decrease in the depth of field

Answer 14

Decreases

Question 15

The rate at which energy is transmitted is referred to as the _________

Answer 15

Power

Question 16

Power per unit area is defined as __________

Answer 16

Intensity

Question 17

If you double the power, the intensity ______

Answer 17

Doubles

Question 18

The piezoelectric effect was first described by the ________ brothers in 1880

Answer 18

Curie

Question 19

Air-filled structures , such as lungs and stomach, or gas-filled structures, such as bowel _______ sound transmission

Answer 19

Impede

Question 20

Bone conducts sound at a ________speed than soft tissue

Answer 20

Faster

Question 21

Normal transmission of sound through soft tissue travels at _________m/sec

Answer 21

1540

Question 22

Acoustic impedance is the product of the ___________ in a medium and the density of that medium

Answer 22

Velocity of Sound

Question 23

The angle of reflection is equal to the _______

Answer 23

Angle of incidence

Question 24

If specular reflectors are aligned __________ to the direction of the transmitted pulse, they reflect sound directly back to the active crystal elements in the transducer and produce a strong signal

Answer 24

Perpendicular

Question 25

The sum of acoustic energy losses resulting from absorption, scattering, and reflection is the ___________

Answer 25

Attenuation

Question 26

Minimum reflector separation along the sound path required to produce separate echoes is _______ resolution

Answer 26

Axial

Question 27

The __________ resolution is the ability to produce separate echoes perpendicular to the sound path; it is affected by the transducer diameter and focusing

Answer 27

Lateral

Question 28

Lateral resolution is determined by _________

Answer 28

Beam width

Question 29

________ resolution refers to the ability to resolve ofbjects that are the same distance from the transducer but are located perpendicular to the plane of imaging

Answer 29

Azimuthal

Question 30

Three criteria that determine the type of transducer selected for a particular examination are . . .

Answer 30

1. Examination
2. Size of patient
3. Amount of fatty or muscular tissue present

Question 31

The number of pulses launched per second is the __________

Answer 31

Pulse repetition frequency (PRF)

Question 32

If the gain is set too ________, artificial echo noise will be displayed throughout the image

Answer 32

High

Question 33

A one-dimensional image displaying the amplitude strength of the returning echo signals along the vertical axis and the time (distance) along the horizontal axis is produced by __________

Answer 33

Amplitude modulation

Question 34

The intensity (amplitude) of an echo attained by varying the brightness of a dot to correspond to echo strength is displayed by the ______________method

Answer 34

Brightness modulation

Question 35

The condition of assigning each level of amplitude a particular shade of gray is referred to as the __________

Answer 35

Gray Scale

Question 36

The __________ displays time along the horizontal axis and depth along the vertical axis to depict movement, especially in cardiac structures

Answer 36

Motion mode

Question 37

A dynamic presentation of multiple image frames per second over selected areas of the body is provided by ________imaging

Answer 37

Real time

Question 38

With pulse Doppler, for accurate detection of Doppler frequencies, the Doppler signal must be sampled at least ______for each cycle in the wave

Answer 38

Twice

Question 39

When the Nyquist limit is exceeded, an artifact called __________occurs

Answer 39

Aliasing