Questão 1
Questão
Blood flow that has consistent velocities within a vessel is known
as what type offlow
Responda
-
Turbulent flow
-
Laminar flow
-
Vortex flow
-
Stagnant flow
Questão 2
Questão
Blood flow that has randomly different velocities is known as what type of
flow
Responda
-
Turbulent flow
-
Laminar flow
-
Vortex flow
-
Stagnant flow
Questão 3
Questão
Blood flow that has high velocities in the center of the vessel but spirals near
walls of a vessel due to a stricture is known as what type of flow
Responda
-
Turbulent flow
-
Laminar flow
-
Vortex flow
-
Stagnant flow
Questão 4
Questão
Blood flow that slows to a point of immobility is known as what type of flow
Responda
-
Turbulent flow
-
Laminar flow
-
Vortex flow
-
Stagnant flow
Questão 5
Questão
Blood flow velocity is measured in what type of unit
Responda
-
Gauss/sec
-
mm/sec
-
cm/sec
-
inches/sec
Questão 6
Questão
Which of the following is the formula that is used to calculate blood flow
velocity
Responda
-
Velocity = Flow volume / Vessel area
-
Velocity = Vessel area / Flow volume
-
Velocity = Flow volume + vessel area
-
Velocity = Vessel area - Flow volume
Questão 7
Questão
Blood flow velocity is greatest near which area of the vessel
Responda
-
Vessel walls
-
Vessel center
-
None of the above
Questão 8
Questão
Blood flow velocity at a given point is dependent upon which factor
Questão 9
Questão
During peak systolic phase of the cardiac cycle, blood flow velocities are
dependent upon what factor(s)
Questão 10
Questão
Which of the following vessels has the highest peak velocity
Responda
-
Ascending aorta
-
Distal aorta
-
Proximal carotids
-
Basilar artery
Questão 11
Questão
Which of the following vessels has the slowest peak velocity
Questão 12
Questão
Typical peak velocities of the ascending aorta are usually within what range
Responda
-
150 - 175 cm/sec
-
100 - 160 cm/sec
-
80 - 120 cm/sec
-
40 - 70 cm/sec
Questão 13
Questão
Typical peak velocities of the distal aorta and iliac vessels are usually
within what range
Responda
-
150 - 175 cm/sec
-
100 - 160 cm/sec
-
80 - 120 cm/sec
-
40 - 70 cm/sec
Questão 14
Questão
Typical peak velocities of the proximal carotid, brachial and superficial
femoral arteries are usually within what range
Responda
-
150 - 175 cm/sec
-
100 - 160 cm/sec
-
80 - 120 cm/sec
-
40 - 70 cm/sec
Questão 15
Questão
Typical peak velocities of the middle and anterior cerebral arteries are
usually within what range
Responda
-
150 - 175 cm/sec
-
100 - 150 cm/sec
-
40 - 70 cm/sec
-
30 - 50 cm/sec
Questão 16
Questão
Typical peak velocities of the vertebral and basilar arteries are usually within
what range
Responda
-
80 - 120 cm/sec
-
50-70 cm/sec
-
30-50 cm/sec
-
under 20 cm/sec
Questão 17
Questão
The speed at which blood flows through an excited slice and only receives
one RF pulse is known as what type of phenomenon
Questão 18
Questão
To produce signal in a spin echo pulse sequence, blood flow must receive
both the 90 degree and the 180 degree RF pulse.
Questão 19
Questão
Blood flow that receives a 90 degree excitation pulse but not a 180 degree
rephasing pulse produces what type of signal
Responda
-
High signal
-
Low signal
-
No signal
Questão 20
Questão
Blood flow that receives a 180 degree rephasing pulse but not a 90 degree
excitation pulse produces what type of signal
Responda
-
High signal
-
Low signal
-
No signal
Questão 21
Questão
The magnitude of time of flight phenomenon effects is dependent upon which
factor(s)
Responda
-
Velocity of flow
-
TE
-
Slice thickness
-
All of the above
Questão 22
Questão
As blood flow velocity increases, the effects of time of flight phenomenon
Responda
-
Increase
-
Decrease
-
Stays the same
Questão 23
Questão
As blood flow velocity decreases, the effects of time of flight phenomenon
Responda
-
Increases
-
Decreases
-
Stays the same
Questão 24
Questão
As the echo time increases, the effects of time of flight phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 25
Questão
As echo time decreases, the effects of time offlight phenomenon
Responda
-
Increases
-
Decreases
-
Stays the same
Questão 26
Questão
As slice thickness increases, the effects of time of flight phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 27
Questão
As slice thickness decreases, the effects of time of flight phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 28
Questão
In a gradient echo pulse sequence, blood flow that receives the initial RF
pulse produces what type of signal
Questão 29
Questão
The flow phenomenon that is characterized by the contrast differences
between fresh flowing nuclei entering a slice and stationary tissue within
that slice is known as
Questão 30
Questão
Entry slice phenomenon is most prominent in what slice of the area scanned
Responda
-
First slice
-
Middle slice
-
Last slice
-
Affects all the same
Questão 31
Questão
The effects of entry slice phenomenon are dependent upon which factor(s)
Responda
-
Repetition time
-
Slice thickness
-
Velocity of flow
-
All of the above
Questão 32
Questão
When TR is decreased, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 33
Questão
When TR is increased, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 34
Questão
When slice thickness is increased, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 35
Questão
When slice thickness is decreased, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 36
Questão
When the velocity of flow increases, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 37
Questão
When the velocity of flow decreases, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 38
Questão
The direction of blood flow is an important factor in determining the effects
of entry slice phenomenon
Questão 39
Questão
Blood flow that travels in the same direction in which the slices are acquired
is known as what type of flow
Responda
-
Counter current flow
-
Vortex flow
-
Stagnant flow
-
Co-current flow
Questão 40
Questão
Blood flow that travels in the opposite direction in which the slices are
acquired is known as what type of flow
Responda
-
Counter current flow
-
Vortex flow
-
Stagnant flow
-
Co-current flow
Questão 41
Questão
When the direction of blood flow is opposite the direction in which slices are
acquired, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 42
Questão
When the direction of blood flow is the same as the direction in which slices
are acquired, the effects of entry slice phenomenon
Responda
-
Increase
-
Decrease
-
Stay the same
Questão 43
Questão
The flow phenomenon that is characterized by phase differences between
flowing and stationary nuclei within a voxel is known as
Questão 44
Questão
The magnitude of intra-voxel dephasing is dependent upon which factor(s)
Questão 45
Questão
In which of the following types of flow can intra-voxel dephasing be
compensated for
Responda
-
Turbulent flow
-
Vortex flow
-
Stagnant flow
-
Laminar flow
Questão 46
Questão
The use of an additional gradient to correct the effects of intra-voxel
dephasing is a technique known as
Responda
-
Gradient moment rephasing
-
Intra-voxel misregistration
-
Gradient moment nulling
-
Gradient moment rephasing & Gradient moment nulling
Questão 47
Questão
Gradient moment nulling is most effective on which type of flow
Responda
-
Slow turbulent flow
-
Fast laminar flow
-
Slow laminar flow
-
Fast vortex flow
Questão 48
Questão
The effects of time of flight and entry slice phenomena can be minimized by
which method
Responda
-
Gradient moment nulling
-
Pre-saturation RF pulse
-
Respiratory compensation
-
None of the above
Questão 49
Questão
The method of acquiring more than one echo that are multiples of each other
to reduce intra-voxel dephasing is known as
Responda
-
Gradient moment nulling
-
Pre-saturation RF pulse
-
Even echo rephasing
-
None of the above
Questão 50
Questão
Which of the following conventional MRI techniques can be used to produce
contrast differences between vascular structures and stationary structures
Questão 51
Questão
Which of the following is the conventional technique used to produce a black
appearance in vascular structures
Responda
-
Short TE, Short TR, Pre-saturation pulse
-
Long TE, Short TR, Gradient moment nulling
-
Long TE, Long TR, Respiratory compensation
-
None of the above
Questão 52
Questão
Which of the following is the conventional technique used to produce a
bright appearance in vascular structures
Responda
-
Pre-saturation pulse
-
Respiratory compensation
-
Gradient moment nulling
-
None of the above
Questão 53
Questão
The vascular imaging method that maximizes vascular contrast while also
suppressing stationary tissue is known as
Questão 54
Questão
Which of the following is a method used inMRAto suppress stationary
tissue
Questão 55
Questão
Which of the following is a method used in MRA to increase signal from
vascular structures
Questão 56
Questão
The type of MRA that uses gradient echo pulse sequences and gradient
moment nulling to enhance flow is known as
Responda
-
Digital subtraction
-
TOFMRA
-
PCMRA
-
Velocity encoding
Questão 57
Questão
In TOF MRA, which method is used to suppress signal from stationary
tissue?
Responda
-
Saturation
-
Subtraction
-
Gradient moment nulling
-
None of the above
Questão 58
Questão
TOF MRA is most sensitive to blood flow that flows in what direction in
relation to the slice
Questão 59
Questão
Which of the following is a disadvantage of TOF MRA
Responda
-
Parallel flow can be suppressed
-
Slow flow can be suppressed
-
Stationary tissue with short Tl relaxation times can produce signal
-
All of the above
Questão 60
Questão
Which of the following is an advantage of TOF MRA
Responda
-
Relatively short scan times
-
Increased sensitivity to flow
-
Decreased sensitivity to intra-voxel dephasing
-
All of the above
Questão 61
Questão
Which of the following TOF MRA sequences is most likely to saturate slow
flow
Questão 62
Questão
The type of MRA that produces image contrast based on the differences in
phase shifts between blood flow and stationary tissue is known as
Responda
-
TOFMRA
-
Velocity encoding
-
PCMRA
-
None ofthe above
Questão 63
Questão
Which of the following type of MRA uses a bipolar gradient to enhance
vascular structures
Responda
-
TOFMRA
-
Bright blood imaging
-
Phase contrast MRA
-
Black Blood imaging
Questão 64
Questão
Which of the following is a type of image that is produced by phase contrast
MRA?
Questão 65
Questão
Which of the following is an advantage of phase contrast MRA
Responda
-
Increased stationary tissue suppression
-
Sensitive to flow in all directions
-
Sensitive to flow with various velocities
-
All of the above
Questão 66
Questão
Which of the following is a disadvantage of phase contrast MRA
Responda
-
Long scan times
-
Reduced intra-voxel dephasing
-
Increased sensitivity to turbulence
-
Long scan times & Increased sensitivity to turbulence
Questão 67
Questão
Which of the following PC MRA techniques provides the highest signal to
noise ratio and spacial resolution
Questão 68
Questão
The method that is most commonly used to reduce artifact produced by
cardiac motion when scanning the chest is known as
Responda
-
Respiratory gating
-
Respiratory compensation
-
Cardiac gating
-
None of the above
Questão 69
Questão
Two types of cardiac gating that are most commonly used are known as
Responda
-
Respiratory gating, Respiratory compensation
-
ECG gating, Peripheral gating
-
Pseudo gating, Respiratory gating
-
None of the above
Questão 70
Questão
The P wave of the ECG represents which phase of the cardiac cycle
Responda
-
Atrial systole
-
Ventricular systole
-
Ventricular diastole
-
Atrial diastole
Questão 71
Questão
The QRS wave of the ECG represents which phase of the cardiac cycle?
Responda
-
Atrial systole
-
Ventricular systole
-
Ventricular diastole
-
Atrial diastole
Questão 72
Questão
The T wave of the ECG represents which phase of the cardiac cycle
Responda
-
Atrial systole
-
Ventricular systole
-
Ventricular diastole
-
Atrial diastole
Questão 73
Questão
During cardiac gating, which wave is used to trigger each pulse sequence
Responda
-
P wave
-
Q wave
-
R wave
-
T wave
Questão 74
Questão
During cardiac gating, the time between two consecutive R waves is known
as
Responda
-
Trigger window
-
Trigger delay
-
R-R interval
-
None of the above
Questão 75
Questão
The ECG wave with the highest electrical amplitude is known as the
Responda
-
R wave
-
Q wave
-
T wave
-
P wave
Questão 76
Questão
During cardiac gating, TR is dependent upon which factor(s)
Questão 77
Questão
During cardiac gating, which factors are affected by having an effective TR
Responda
-
Image weighting
-
Number of slices
-
Scan time
-
All of the above
Questão 78
Questão
During cardiac gating, the waiting time between the R wave and the start of
the data acquisition is known as
Responda
-
Repetition time
-
Inversion time
-
Trigger delay
-
Echo delay
Questão 79
Questão
During cardiac gating, the waiting time before each R wave is known as
Responda
-
Repetition time
-
Inversion time
-
Trigger delay
-
Trigger window
Questão 80
Questão
During cardiac gating, which of the following is the formula used to calculate
available imaging time
Questão 81
Questão
The type of cardiac gating that detects the increase in blood volume in the
capillary bed during systole is known as
Responda
-
ECG gating
-
Pseudo gating
-
Peripheral gating
-
None of the above
Questão 82
Questão
During cardiac gating, one R-R interval and a short TE is used to produce
what type of image
Responda
-
T1 weighting
-
T2 weighting
-
Proton density weighting
-
None of the above