ARMRIT FINAL EXAM ACTUAL QUESTIONS AND
SOLUTIONS GRADED A+
✔✔the component Mz is most associated with:
A) anti-parallel to B0; T2 relaxation; net magnetization
B) transverse to B0; T2 relaxation; transverse magnetization
C) parallel to B0; T1 relaxation; longitudinal magnetization
D) perpendicular to B0; T2 decay; FID - ✔✔parallel to B0; T1 relaxation; longitudinal
magnetization
✔✔the component Mxy is most associated with:
A) anti-parallel to B0; T1 relaxation; net magnetization
B) transverse to B0; T2 relaxation; transverse magnetization
C) parallel to B0; T1 relaxation; longitudinal magnetization
D) perpendicular to B0; T2 decay; FID - ✔✔transverse to B0; T2 relaxation; transverse
magnetization
✔✔in the USA, MRI systems in clinical use have main magnetic field strengths that
range from:
A) 2T to 6T
B) 0.06T to 3T
C) 2 Gauss to 6 Gauss
D) 0.006T to 0.03T - ✔✔0.06T to 3T
✔✔On a very basic level, the 3 basic components required to attain MR signals are:
A) Magnetic field, proton, ionizing radiation
B) magnetic field, electron, ionizing radiation
C) magnetic field, electron, radio wave
D) magnetic field, proton, radio wave - ✔✔magnetic field, proton, radio wave
✔✔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 the type of
magnet). the transmitted radio frequency, in comparison, is described as:
A) constant and always parallel to B0
B) oscillating and always parallel to B0
C) constant and always perpendicular to B0
D) oscillating and always perpendicular to B0 - ✔✔oscillating and always perpendicular
to B0
✔✔which of the following parameters controls the amount of contrast seen in an image
due to T2 relaxation
A) T1
B) TE
C) TR
,D) None of these - ✔✔TE
✔✔a magnetic field strength of 0.5T is equivalent to:
A) 1500 G
B) 5000 G
C) 1 G
D) 10000 G - ✔✔5000 G
✔✔an example of a dipole is:
A) a hydrogen nucleus
B) a bar magnet
C) the earth
D) all of the above - ✔✔all of the above
✔✔hydrogen nuclei have a magnetic moment because they poses a property called:
A) inversion
B) flux
C) spin
D) resonance - ✔✔spin
✔✔protons that align in an anti-parallel direction are in:
A) an expanded energy state
B) a resonant condition
C) a high energy state
D) in constant state of flux - ✔✔a high energy state
✔✔the formula that described the relationship between the static magnetic field and the
precessional frequencyof the hydrogen proton is the:
A) Hemholtz relationship
B) nyquist theorem
C) larmor equation
D) bloch equation - ✔✔larmor equation
✔✔to calculate the precessional frequency, the strength of the static magnetic field is
multiplied by the constant known as:
A) the gyromagnetic ratio
B) Tau
C) Alpha 1
D) linear attenuation coefficient - ✔✔the gyromagnetic ratio
✔✔the field strength of an MR imaging magnet as measured within the bore is most
typically expressed in terms of:
A) tesla
B) gauss
, C) Megahertz
D) magneto-gyric ratio - ✔✔tesla
✔✔the larmor, precessional or resonance frequency of hydrogen proton in a statc
magnetic field of .5T is approximately:
A) 42.576 MHz
B) 63.864 MHz
C) 25.5456 MHz
D) 21.288 MHz - ✔✔21.288 MHz
✔✔following RF excitation, as transverse magnetization (Mxy) decays to zero, the MR
signal ___________.
A) increases exponentially
B) becomes saturated
C) decays to zero
D) in phase coherent - ✔✔decays to zero
✔✔RF pulses are identified according to the:
A) gradient
B) intensity
C) duration
D) flip angle - ✔✔flip angle
✔✔following the excitation pulse, the FID decays ____________.
A) along the z axis
B) exponentially
C) during the 180 degree RF pulse
D) linearly - ✔✔exponentially
✔✔of the following tissues, which has the longest T2 value?
A) fat
B) muscle
C) CSF
D) white matter - ✔✔CSF
✔✔of the following tissues, which has the shortest T1 value
A) fat
B) muscle
C) liver
D) white matter - ✔✔fat
✔✔MRI magnets that require a steady current of electricity passed through coils
wrapped around an iron or air core are:
A) high field
SOLUTIONS GRADED A+
✔✔the component Mz is most associated with:
A) anti-parallel to B0; T2 relaxation; net magnetization
B) transverse to B0; T2 relaxation; transverse magnetization
C) parallel to B0; T1 relaxation; longitudinal magnetization
D) perpendicular to B0; T2 decay; FID - ✔✔parallel to B0; T1 relaxation; longitudinal
magnetization
✔✔the component Mxy is most associated with:
A) anti-parallel to B0; T1 relaxation; net magnetization
B) transverse to B0; T2 relaxation; transverse magnetization
C) parallel to B0; T1 relaxation; longitudinal magnetization
D) perpendicular to B0; T2 decay; FID - ✔✔transverse to B0; T2 relaxation; transverse
magnetization
✔✔in the USA, MRI systems in clinical use have main magnetic field strengths that
range from:
A) 2T to 6T
B) 0.06T to 3T
C) 2 Gauss to 6 Gauss
D) 0.006T to 0.03T - ✔✔0.06T to 3T
✔✔On a very basic level, the 3 basic components required to attain MR signals are:
A) Magnetic field, proton, ionizing radiation
B) magnetic field, electron, ionizing radiation
C) magnetic field, electron, radio wave
D) magnetic field, proton, radio wave - ✔✔magnetic field, proton, radio wave
✔✔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 the type of
magnet). the transmitted radio frequency, in comparison, is described as:
A) constant and always parallel to B0
B) oscillating and always parallel to B0
C) constant and always perpendicular to B0
D) oscillating and always perpendicular to B0 - ✔✔oscillating and always perpendicular
to B0
✔✔which of the following parameters controls the amount of contrast seen in an image
due to T2 relaxation
A) T1
B) TE
C) TR
,D) None of these - ✔✔TE
✔✔a magnetic field strength of 0.5T is equivalent to:
A) 1500 G
B) 5000 G
C) 1 G
D) 10000 G - ✔✔5000 G
✔✔an example of a dipole is:
A) a hydrogen nucleus
B) a bar magnet
C) the earth
D) all of the above - ✔✔all of the above
✔✔hydrogen nuclei have a magnetic moment because they poses a property called:
A) inversion
B) flux
C) spin
D) resonance - ✔✔spin
✔✔protons that align in an anti-parallel direction are in:
A) an expanded energy state
B) a resonant condition
C) a high energy state
D) in constant state of flux - ✔✔a high energy state
✔✔the formula that described the relationship between the static magnetic field and the
precessional frequencyof the hydrogen proton is the:
A) Hemholtz relationship
B) nyquist theorem
C) larmor equation
D) bloch equation - ✔✔larmor equation
✔✔to calculate the precessional frequency, the strength of the static magnetic field is
multiplied by the constant known as:
A) the gyromagnetic ratio
B) Tau
C) Alpha 1
D) linear attenuation coefficient - ✔✔the gyromagnetic ratio
✔✔the field strength of an MR imaging magnet as measured within the bore is most
typically expressed in terms of:
A) tesla
B) gauss
, C) Megahertz
D) magneto-gyric ratio - ✔✔tesla
✔✔the larmor, precessional or resonance frequency of hydrogen proton in a statc
magnetic field of .5T is approximately:
A) 42.576 MHz
B) 63.864 MHz
C) 25.5456 MHz
D) 21.288 MHz - ✔✔21.288 MHz
✔✔following RF excitation, as transverse magnetization (Mxy) decays to zero, the MR
signal ___________.
A) increases exponentially
B) becomes saturated
C) decays to zero
D) in phase coherent - ✔✔decays to zero
✔✔RF pulses are identified according to the:
A) gradient
B) intensity
C) duration
D) flip angle - ✔✔flip angle
✔✔following the excitation pulse, the FID decays ____________.
A) along the z axis
B) exponentially
C) during the 180 degree RF pulse
D) linearly - ✔✔exponentially
✔✔of the following tissues, which has the longest T2 value?
A) fat
B) muscle
C) CSF
D) white matter - ✔✔CSF
✔✔of the following tissues, which has the shortest T1 value
A) fat
B) muscle
C) liver
D) white matter - ✔✔fat
✔✔MRI magnets that require a steady current of electricity passed through coils
wrapped around an iron or air core are:
A) high field
