Ultrasound Review

Front 1

widening of the sound beam is demonstrated in the

Back 1

fraunhofer zone

Front 2

weak beams emitted from a linear sequenced array transducer are termed

Back 2

grating lobes

Front 3

the resonant frequency of a pulse wave is determined by the

Back 3

thickness and propagation speed of the element

Front 4

heat sterilization is not recommended for diagnostic transducers because

Back 4

the piezoelectric properties will be lost

Front 5

which of the following compontnts is unnecessary in the construction of a continuous wave transducer

Back 5

damping layer

Front 6

lateral resolution is determined by the

Back 6

beam width

Front 7

what is the axial resolution in soft tissue when using a 5 MHz frequency with a two cycle pulse and an element thickness of 0.5mm

Back 7

0.3 mm

Front 8

what is the operating frequency of a two cycle pulse with an element thickness of 0.2 mm and a propagation speed of 4 mm / us

Back 8

10 MHz

Front 9

which of the following principles do diagnostic ultrasound transducers operate?

snell's law

ALARA principle

Hugens principle

piezoelectric effect

Back 9

piezoelectric effect

Front 10

reducing the impedance difference between the crystal and the skin is the primary function of what transducer component

Back 10

matching layer

Front 11

a sound beam demonstrates the most uniform intensity in the

Back 11

far field

Front 12

what is the near zone length of a 6 mm 5MHz transducer

Back 12

30mm

Front 13

which of the following changes will improve temporal resolution

increase the beam width

increase focal zone depth

decrease the depth

decrease in dynamic range

Back 13

decrease the depth

Front 14

The near zone length of a 3 mm 10 MHz transducer is

Back 14

15mm

Front 15

which of the following transducers elements has the longest focal length

7mm, 2.5 MHz

2mm, 7.5 MHz

5mm, 10 MHz

3mm, 15 MHz

Back 15

5mm, 10MHz

Front 16

the distance from the face of a focused transducer to the point of spatial peak intensity is termed the

Back 16

focal length

Front 17

Irregular excitation of the elements in an array to reduce grating lobes describes

Back 17

apodization

Front 18

diameter of the transducer describes the

Back 18

diameter of the focus

Front 19

the impedance of the damping layer is

Back 19

similar to the element's

Front 20

the purpose of backing material in the transducer is to

Back 20

reduce the number of cycles in a pulse

Front 21

vector array is a type of transducer

Back 21

operation

Front 22

focusing of the sound beam is directly related to

Back 22

lateral resolution

Front 23

steering of the sound beam is accomplished by

Back 23

altering the excitation of the active elements

Front 24

exceeding the curie point of a transducer wll result in

Back 24

loss of all piezoelectric properties

Front 25

an active element with a thickness of 0.8 mm and a propagation speed of 4 mm/us will have an operating frequency of

Back 25

2.5MHz

Front 26

what is the thickness of the crystal with an operating frequency of 5 MHz and a propagation speed of 4 mm/us?

Back 26

0.4 mm

Front 27

what is the axial resolution in soft tissue when using a 15 MHz frequency with a two cycle pulse

Back 27

0.1 mm

Front 28

which of the following transducers operates by applying voltage pulses to groups of linear elements in succession

Back 28

linear sequenced array

Front 29

focusing of the sound beam is only accomplished within the

Back 29

near field

Front 30

what is the diameter of the sound beam at one near zone length when using a 6mm 2.5 MHz transducer

Back 30

3mm

Front 31

the ability to distinguish two structures in a path perpendicular to the sound beam describes

Back 31

azimuthal resolution

Front 32

the most common piezoelectric material used in diagnostic ultrasound transducers is

Back 32

lead zirconate titanate

Front 33

subdicing the elements in diagnostic ultrasound transducers is used to

Back 33

reduce grating lobes

Front 34

diagnostic frequencies range between

Back 34

2 and 20 MHz

Front 35

which of the following changes will improve axial resolution

Back 35

increase in transducer frequency

Front 36

during transmission diagnostic ultrasound transducers convert

Back 36

electrical energy into thermal energy

Front 37

which of the following states "some materials produce a voltage when distorted by an applied pressure"

Back 37

piezoelectric principle

Front 38

which of the following is a negative effect of using a damping material in the transducer assembly

Back 38

reduced sensitivity

Front 39

how many cycles pre pulse are typically used in doppler imaging

Back 39

5-30

Front 40

the sonographer can determine the depth of the focal zone when using a transducer with an

Back 40

electronic focus

Front 41

the impedance of the matching layer is

Back 41

less than the impedance of the crystal

Front 42

which of the following transducers displays a trapezoidal image?

convex

vector

annular

curvilinear

Back 42

vector

Front 43

which of the following differentiates similar or dissimilar tissues?

axial resolution

lateral resolution

contrast resolution

temporal resolution

Back 43

contrast resolution

Front 44

section thickness is related to the

Back 44

beam width

Front 45

operating frequency of a transducer is directly related to the

Back 45

propagation speed of the element

Front 46

a focused 10 mm 15 MHz transducer will demonstrate a focal diameter of

Back 46

5 mm