Correct Answers
Which type of flow has a constant velocity across the vessel?
a. Plug
b. Stagnant
c. Laminar
d. Vortex
e. Turbulent - Correct Answer A
Which type of flow occurs in the center of the vessel?
a. Plug
b. Stagnant
c. Laminar
d. Vortex
e. Turbulent - Correct Answer C
Which type of flow travels at different velocities in the vessels?
a. Plug
b. Stagnant
c. Laminar
d. Vortex
e. Turbulent - Correct Answer E
Which type of flow starts out as laminar flow but becomes erratic as it passes through the stricture in
the vessel?
a. Plug
b. Stagnant
,c. Laminar
d. Vortex
e. Turbulent - Correct Answer D
Which type of flow moves very slow?
a. Plug
b. Stagnant
c. Laminar
d. Vortex
e. Turbulent - Correct Answer B
Which of the following flow mechanisms is often termed the 1st order of motion?
a. Laminar flow
b. Jerk motion
c. Accelerated motion
d. None of the above - Correct Answer A
Which of the following flow mechanisms is often termed the 2nd order of motion?
a. Laminar flow
b. Jerk motion
c. Accelerated motion
d. None of the above - Correct Answer C
Which of the following flow mechanisms is often termed the 3rd order of motion?
a. Laminar flow
b. Jerk motion
c. Accelerated motion
,d. None of the above - Correct Answer B
Which of the following flow mechanisms, at the present time, is the only flow that can be
compensated for?
a. Laminar flow
b. Jerk motion
c. Accelerated motion
d. None of the above - Correct Answer A
All the following are flow phenomena except?
a. Time of Flight (TOF)
b. Entry Slice
c. Slow Flow
d. Intra-voxel Dephasing - Correct Answer C
In order to produce a MRI signal, the nuclei must only receive an excitation pulse.
a. True
b. False - Correct Answer B - nuclei must receive an excitation pulse and a rephasing pulse or gradient
reversal
_______ flow phenomena occurs when nuclei move, between the application of the excitation pulse
and the rephasing of the magnetization, and do not receive both of these experiences.
a. Time of Flight (TOF)
b. Entry Slice
c. Slow Flow
d. Intra-voxel Dephasing - Correct Answer A
In the TOF phenomena, which of the following occurs during a spin echo sequence?
, a. Signal void
b. Signal enhancements
c. A and B
d. None of the above - Correct Answer A
In the TOF phenomena, which of the following occurs during a gradient echo sequence?
a. Signal void
b. Signal enhancements
c. A and B
d. None of the above - Correct Answer B
Which of the following increases the TOF phenomena in the spin echo sequence?
a. Increase velocity of nuclei
b Decrease velocity of nuclei - Correct Answer A
Which of the following increases the TOF phenomena in the spin echo sequence?
a. Increase TE (long echo times)
b. Decrease TE (short echo times) - Correct Answer A
Which of the following increases the TOF phenomena in the spin echo sequence?
a. Increase slice thickness
b. Decrease slice thickness - Correct Answer B
Which of the following increases the TOF phenomena in a gradient echo sequence?