armrit study guide questions with complete
solutions
At any one time, human body tissue, in general, is made up of 50 - 90% of what
| | | | | | | | | | | | | | | | | |
substance?
a. C13
|
b. NA 23
| |
c. H²O
|
d. H
|
H²O
Tissues that are very efficient at spin-lattice interactions near the Larmor
| | | | | | | | | | |
frequency, such as fatty tissues, should have:
| | | | | |
Low T1 values and produces hyperintense signals.
| | | | | |
High T1 values and produce hyperintense signals.
| | | | | |
High T1 values and produce hypointense signals.
| | | | | |
Low T1 values and produce hypointense signals.
| | | | | |
Low T1 values and produces hyperintense signals.
| | | | | |
The Larmor frequency of hydrogen protons in a 1.5 Tesla magnetic field is:
| | | | | | | | | | | |
6.4 MHz/Tesla.
|
MHz/Tesla.
25.5 MHz/Tesla. |
63.9 MHz/Tesla. |
,63.9 MHz/Tesla.
|
In clinical MR imaging of the human body, the substance of interest is:
| | | | | | | | | | | |
H.
NA23.
P31.
H²O.
H. (hydrogen)
|
The main magnetic field of the MRI system is described as constant and always
| | | | | | | | | | | | | |
oriented in one set direction, either horizontal or vertical (dependent on type of
| | | | | | | | | | | | |
magnet). The transmitted radio-frequency, in comparison, is described as:
| | | | | | | |
Constant and always parallel to Bo.
| | | | |
Oscillating and always parallel to Bo.| | | | |
Constant and always perpendicular to Bo.
| | | | |
Oscillating and always perpendicular to Bo.
| | | | |
Oscillating and always perpendicular to Bo.
| | | | |
The component Mxy is most associated with:
| | | | | |
Anti-parallel to Bo; T1 relaxation; net magnetization.
| | | | | |
Transverse to Bo; T2 relaxation; transverse magnetization.
| | | | | |
Parallel to Bo; T1 relaxation; longitudinal magnetization.
| | | | | |
Perpendicular to B1; T1 decay; FID. | | | | |
Transverse to Bo; | |
T2 relaxation;
|
transverse magnetization. |
The T2 process is also known as:
| | | | | |
,Spin-Spin.
Spin density.
|
Spin-Lattice.
Spin-warp.
Spin-Spin.
Magnetic fields have strength and direction, which are represented by a:
| | | | | | | | | |
Field line.
|
Axis.
Vector.
Gauss line. |
Vector.
Once in the main magnetic field, a majority of hydrogen protons will align
| | | | | | | | | | | | |
themselves:
Anti-parallel to Bo. | |
Orthogonal to Bo. | |
Parallel to Bo. | |
Randomly in Bo | |
Parallel to Bo. | |
Because of the spinning motion of the hydrogen proton it has the same
| | | | | | | | | | | | |
properties as a bar magnet. The hydrogen proton's spinning motion gives it a:
| | | | | | | | | | | |
Magnetic charge. |
Magnetic spin. |
Magnetic moment. |
Magnetic precession. |
, Magnetic moment. |
The effects of main magnetic field inhomogeneities on the FID signal are
| | | | | | | | | | | |
corrected for in a Spin-echo sequence by applying a second radio-frequency pulse.
| | | | | | | | | | |
The flip angle of this radio-frequency pulse is:
| | | | | | | |
45 degrees.
|
60 degrees.
|
90 degrees.
|
180 degrees.|
180 degrees.|
MRI terms and symbols which are oriented with and superimposed on the symbol
| | | | | | | | | | | |
of Bo are:
| | |
-Transverse magnetization, Mxy, X axis, Y axis.
| | | | | |
-Net magnetization, antiparallel, high energy level.
| | | | |
-Equilibrium, parallel, longitudinal magnetization, Mz, Z axis.
| | | | | |
Equilibrium, parallel, longitudinal magnetization, Mz, Z axis.
| | | | | |
In a large main magnetic field such as those employed in MRI, the motion of a
| | | | | | | | | | | | | | | |
hydrogen proton has been described as wobbling like a spinning top. This motion
| | | | | | | | | | | | |
is called:
|
A.Precession.
B.Resonance.
C.Frequency.
D.Angular momentum. |
A.Precession.
solutions
At any one time, human body tissue, in general, is made up of 50 - 90% of what
| | | | | | | | | | | | | | | | | |
substance?
a. C13
|
b. NA 23
| |
c. H²O
|
d. H
|
H²O
Tissues that are very efficient at spin-lattice interactions near the Larmor
| | | | | | | | | | |
frequency, such as fatty tissues, should have:
| | | | | |
Low T1 values and produces hyperintense signals.
| | | | | |
High T1 values and produce hyperintense signals.
| | | | | |
High T1 values and produce hypointense signals.
| | | | | |
Low T1 values and produce hypointense signals.
| | | | | |
Low T1 values and produces hyperintense signals.
| | | | | |
The Larmor frequency of hydrogen protons in a 1.5 Tesla magnetic field is:
| | | | | | | | | | | |
6.4 MHz/Tesla.
|
MHz/Tesla.
25.5 MHz/Tesla. |
63.9 MHz/Tesla. |
,63.9 MHz/Tesla.
|
In clinical MR imaging of the human body, the substance of interest is:
| | | | | | | | | | | |
H.
NA23.
P31.
H²O.
H. (hydrogen)
|
The main magnetic field of the MRI system is described as constant and always
| | | | | | | | | | | | | |
oriented in one set direction, either horizontal or vertical (dependent on type of
| | | | | | | | | | | | |
magnet). The transmitted radio-frequency, in comparison, is described as:
| | | | | | | |
Constant and always parallel to Bo.
| | | | |
Oscillating and always parallel to Bo.| | | | |
Constant and always perpendicular to Bo.
| | | | |
Oscillating and always perpendicular to Bo.
| | | | |
Oscillating and always perpendicular to Bo.
| | | | |
The component Mxy is most associated with:
| | | | | |
Anti-parallel to Bo; T1 relaxation; net magnetization.
| | | | | |
Transverse to Bo; T2 relaxation; transverse magnetization.
| | | | | |
Parallel to Bo; T1 relaxation; longitudinal magnetization.
| | | | | |
Perpendicular to B1; T1 decay; FID. | | | | |
Transverse to Bo; | |
T2 relaxation;
|
transverse magnetization. |
The T2 process is also known as:
| | | | | |
,Spin-Spin.
Spin density.
|
Spin-Lattice.
Spin-warp.
Spin-Spin.
Magnetic fields have strength and direction, which are represented by a:
| | | | | | | | | |
Field line.
|
Axis.
Vector.
Gauss line. |
Vector.
Once in the main magnetic field, a majority of hydrogen protons will align
| | | | | | | | | | | | |
themselves:
Anti-parallel to Bo. | |
Orthogonal to Bo. | |
Parallel to Bo. | |
Randomly in Bo | |
Parallel to Bo. | |
Because of the spinning motion of the hydrogen proton it has the same
| | | | | | | | | | | | |
properties as a bar magnet. The hydrogen proton's spinning motion gives it a:
| | | | | | | | | | | |
Magnetic charge. |
Magnetic spin. |
Magnetic moment. |
Magnetic precession. |
, Magnetic moment. |
The effects of main magnetic field inhomogeneities on the FID signal are
| | | | | | | | | | | |
corrected for in a Spin-echo sequence by applying a second radio-frequency pulse.
| | | | | | | | | | |
The flip angle of this radio-frequency pulse is:
| | | | | | | |
45 degrees.
|
60 degrees.
|
90 degrees.
|
180 degrees.|
180 degrees.|
MRI terms and symbols which are oriented with and superimposed on the symbol
| | | | | | | | | | | |
of Bo are:
| | |
-Transverse magnetization, Mxy, X axis, Y axis.
| | | | | |
-Net magnetization, antiparallel, high energy level.
| | | | |
-Equilibrium, parallel, longitudinal magnetization, Mz, Z axis.
| | | | | |
Equilibrium, parallel, longitudinal magnetization, Mz, Z axis.
| | | | | |
In a large main magnetic field such as those employed in MRI, the motion of a
| | | | | | | | | | | | | | | |
hydrogen proton has been described as wobbling like a spinning top. This motion
| | | | | | | | | | | | |
is called:
|
A.Precession.
B.Resonance.
C.Frequency.
D.Angular momentum. |
A.Precession.
