ARRT review - MRI registry review program
|QUESTIONS AND ANSWERS| LATEST UPDATE
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Terms in this set (396)
An RF pulse of what flip angle will c.
maximize the component of the net
magnetization projected into the
transverse plane?
a. 180
b. 120
c. 90
d. 45
T1 relaxation refers to ____ relaxation. b.
a. spin-spin
b. longitudinal
c. phase
d. transverse
,Which of the following statements is c.
false?
a. T1 relaxation refers to longitudinal
recovery of magnetization while T2
relaxation refers to the transverse
decay of magnetization
b. T1 relaxation and T2 relaxation
occur simultaneously
c. echoes collected in the transverse
plane demonstrate only T2 relaxation
differences
d. T2 relaxation occurs much more
quickly than T1 relaxation
If the precessional frequency of the Larmor frequency equation
patient's protons is approximately 21
MHz, what magnetic field strength is W0= B0 x Y
being experienced by the patients
protons? 21= 42.6 x (X)
21/42.6 = .4929 (round) = 0.5T
Which of the following is the a.
definition of T1 relaxation?
a. the time is takes the net
longitudinal magnetization of
protons to grow 63% of its final
amplitude
b. the time at which is takes the
transverse magnetization has
decayed 63% of its full value
,Based on the graph of longitudinal a.
relaxation shown above, which of the
following would have the brightest
signal intensity on T1 image?
a. bone marrow
b. intervertebral disk
c. CSF
d. muscle
(post test 1; page 1)
Based on the graph of longitudinal a.
relaxation shown above, which of the
following would have the shortest T1
relaxation time?
a. bone marrow
b. intervertebral disk
c. CSF
d. muscle
(post test 1; page 1)
, The edema associated with d.
pathology in the brain has a much
longer T2 relaxation time than
surrounding normal brain tissue. On a
T2 image, what does this result in?
a. isointense between edema and
surrounding normal brain tissue
b. a low signal intensity in the area of
edema
c. a signal void in the area of edema
d. a high signal intensity in the area of
edema
Which of the following dephasing d.
mechanisms affects the size of the
resulting spin echo?
a. magnetic field inhomogenities
b. phase effects of chemical shift
c. magnetic susceptibility
d. spin-spin interactions
After a 90 RF pulse, if three 180 RF d.
pulses are applied to generate three
echoes, which of the following is
responsible for the third echo being
much smaller than the first echo?
a. magnetic field inhomogenities
b. phase effects of chemical shift
c. magnetic susceptibility
d. spin-spin interactions
|QUESTIONS AND ANSWERS| LATEST UPDATE
Save
Terms in this set (396)
An RF pulse of what flip angle will c.
maximize the component of the net
magnetization projected into the
transverse plane?
a. 180
b. 120
c. 90
d. 45
T1 relaxation refers to ____ relaxation. b.
a. spin-spin
b. longitudinal
c. phase
d. transverse
,Which of the following statements is c.
false?
a. T1 relaxation refers to longitudinal
recovery of magnetization while T2
relaxation refers to the transverse
decay of magnetization
b. T1 relaxation and T2 relaxation
occur simultaneously
c. echoes collected in the transverse
plane demonstrate only T2 relaxation
differences
d. T2 relaxation occurs much more
quickly than T1 relaxation
If the precessional frequency of the Larmor frequency equation
patient's protons is approximately 21
MHz, what magnetic field strength is W0= B0 x Y
being experienced by the patients
protons? 21= 42.6 x (X)
21/42.6 = .4929 (round) = 0.5T
Which of the following is the a.
definition of T1 relaxation?
a. the time is takes the net
longitudinal magnetization of
protons to grow 63% of its final
amplitude
b. the time at which is takes the
transverse magnetization has
decayed 63% of its full value
,Based on the graph of longitudinal a.
relaxation shown above, which of the
following would have the brightest
signal intensity on T1 image?
a. bone marrow
b. intervertebral disk
c. CSF
d. muscle
(post test 1; page 1)
Based on the graph of longitudinal a.
relaxation shown above, which of the
following would have the shortest T1
relaxation time?
a. bone marrow
b. intervertebral disk
c. CSF
d. muscle
(post test 1; page 1)
, The edema associated with d.
pathology in the brain has a much
longer T2 relaxation time than
surrounding normal brain tissue. On a
T2 image, what does this result in?
a. isointense between edema and
surrounding normal brain tissue
b. a low signal intensity in the area of
edema
c. a signal void in the area of edema
d. a high signal intensity in the area of
edema
Which of the following dephasing d.
mechanisms affects the size of the
resulting spin echo?
a. magnetic field inhomogenities
b. phase effects of chemical shift
c. magnetic susceptibility
d. spin-spin interactions
After a 90 RF pulse, if three 180 RF d.
pulses are applied to generate three
echoes, which of the following is
responsible for the third echo being
much smaller than the first echo?
a. magnetic field inhomogenities
b. phase effects of chemical shift
c. magnetic susceptibility
d. spin-spin interactions
