Image Formation Exam

Question 1

Which item is used to measure section thickness parameters?
a. simulated cysts
b. thin scattering layer
c. nylon fibers
d. attenuating scattering material
e. hyperechoic and hypoechoic simulated lesions

Answer 1

b. thin scattering layer

Question 2

Flow increases if ____ increase(s)
a. pressure difference
b. pressure gradient
c. resistance
d. a and b
e. all of the above

Answer 2

d. a and b

Question 3

The display generally will have a dynamic range ____ than other portions of the ultrasound instrument.
a. larger
b. smaller

Answer 3

b. smaller

Question 4

Increasing ensemble length _____ color sensitivity and accuracy and _____ frame rate.
a. Improves, increases
b. Degrades, increases
c. Degrades, decreases
d. Improves, decreases
e. None of the above

Answer 4

d. Improves, decreases

Question 5

What ultrasound term best describes the structure delineated by the calipers?
a. isoechoic
b. anechoic
c. hypoechoic
d. hyerechoic

Answer 5

b. anechoic

Question 6

Heating depends most directly on ____.
a. SPTP intensity
b. SATA intensity
c. SATP intensity
d. pressure

Answer 6

b. SATA intensity

Question 7

Which of the following controls affect instrument output intensity?
a. Dynamic range, compression
b. Transmit, output
c. Overall gain
d. Slope, time gain compensation
e. Near gain, far gain

Answer 7

b. Transmit, output

Question 8

Flow resistance depends most strongly on ____.
a. vessel length
b. vessel radius
c. blood viscosity
d. all of the above
e. none of the above

Answer 8

b. vessel radius

Question 9

If operating frequency is 5 MHz, Doppler angle is 60 degrees, pulse repetition frequency is 9 kHz, and the Doppler shift is 2 kHz, what problem is encountered if the angle is changed to zero?
a. mirror image
b. range ambiguity
c. refraction
d. aliasing
e. none

Answer 9

e. none

Question 10

Volumetric flow rate decreases with an increase in ____.
a. pressure difference
b. vessel radius
c. vessel length
d. blood viscosity
e. c and d

Answer 10

e. c and d

Question 11

The _____ _____ stores the grey scale image and allows it to be displayed on a computer monitor.
a. postprocessor
b. signal processor
c. preprocessor
d. image memory

Answer 11

d. image memory

Question 12

The following increase(s) the amount of color appearing in a vessel.
a. increase pulse repetition frequency
b. increased wall filter and color gain
c. increased priority and wall filter
d. increased color gain and priority

Answer 12

d. increased color gain and priority

Question 13

When harmonic imaging mode is used, image data is acquired from frequencies at least ____-____ that the transmitted frequency.
a. two times-higher
b. one half-lower
c. four times-higher
d. one quarter-lower

Answer 13

a. two times-higher

Question 14

In practice, approximately ______ pulses are required to obtain one line of color Doppler information.
a. 1
b. 10
c. 100
d. 1000
e. 1,000,000

Answer 14

b. 10

Question 15

If pulse duration is 1 microsecond and the pulse repetition period is 100 microseconds, duty factor is ____
a. 50%
b. 90%
c. 1%
d. 100%
e. 10%

Answer 15

c. 1%

Question 16

Echo intensity is represented in an image memory by _________ .
a. Positive charge distribution
b. A number
c. Electron density of the display writing beam
d. a and c
e. All of the above

Answer 16

b. A number

Question 17

The important characteristic of the material used in hydrophones is ____
a. bandwidth
b. propagation speed
c. impedance
d. density
e. efficiency

Answer 17

a. bandwidth

Question 18

Two different colors in the same vessel indicate ____.
a. flow reversal
b. sector scan
c. vessel curvature
d. aliasing
e. any of the above

Answer 18

e. any of the above

Question 19

The Doppler effect is a change in ____.
a. intensity
b. wavelength
c. frequency
d. all of the above
e. b and c

Answer 19

e. b and c

Question 20

The characteristic of a fluid that offers resistance to flow is called ____.
a. density
b. inertia
c. impedance
d. resistance
e. viscosity

Answer 20

e. viscosity