Part D: Fundamentals

Question 1

43. In the equation associated with Larmor Equation, B₀ stands for:
    a. Static magnetic field
    b. Frequency
    c. Gyromagnetic ratio
    d. Voltage

Answer 1

a. Static magnetic field

Question 2

44. In the equation associated with Larmor Equation, ω₀ stands for:
    a. Static magnetic field
    b. Frequency
    c. Gyromagnetic ratio
    d. voltage

Answer 2

b. Frequency

Question 3

45. In the equation associated with Larmor Equation, y stands for:
    a. Static magnetic field
    b. Frequency
    c. Gyromagnetic ratio
    d. voltage

Answer 3

c. Gyromagnetic ratio

Question 4

46. A magnetic field strength of 0.5T is equivalent to:
    a. 15 000 G
    b. 5 000 G
    c. 1 G
    d. 10 000G

Answer 4

b. 5 000 G

Question 5

47. A condition whereby there are MORE spins ‘in line’ with the magnetic field than ‘opposed’ is known as:
    a. Low energy
    b. High energy
    c. Thermal equilibrium
    d. Excitation

Answer 5

c. Thermal equilibrium

Question 6

48. During thermal equilibrium there are:
    a. More spins in the low energy state
    b. More spins in the high energy state
    c. Equal number spins in the low and high energy state
    d. Less spins in the low energy state

Answer 6

a. More spins in the low energy state

Question 7

49. Proton spins that are ‘in line’ with the static magnetic field (B₀) are referred to as all of the following EXCEPT:
    a. Spin up
    b. Parallel
    c. Low energy spins
    d. High energy spins

Answer 7

d. High energy spins

Question 8

50. The microscopic magnetic field associated with the proton within the magnetic field is known as the:
    a. Free induction decay (FID)
    b. Magnetic moment (μ)
    c. Signal echo (SE)
    d. Field of view (FOV)

Answer 8

b. Magnetic moment (μ)

Question 9

51. During thermal equilibrium, the vector that represents the ‘spin excess’ is known as the:
    a. Free induction decay (FID)
    b. Net magnetisation vector (NMV)
    c. Signal echo (SE)
    d. Field of view (FOV)

Answer 9

b. Net magnetisation vector (NMV)

Question 10

52. The RF pulse is applied to achieve a condition known as:
    a. Thermal equilibrium
    b. Excitation
    c. Relaxation
    d. Scan timing

Answer 10

b. Excitation

Question 11

53. During excitation, all of the following occur EXCEPT:
    a. Low energy spins enter the high energy state
    b. Spins begin to precess ‘in phase’
    c. The net magnetisation is transferred into the transverse (x/y) plane
    d. High energy spins return to the low energy state

Answer 11

d. High energy spins return to the low energy state

Question 12

54. During relaxation, all of the following occur EXCEPT:
    a. Low energy spins enter the high energy state
    b. High energy spins return to the low energy state
    c. Spins begin to precess ‘out of phase’ or lose phase coherence
    d. The net magnetisation recovers longitudinally

Answer 12

a. Low energy spins enter the high energy state

Question 13

55. T1 relaxation is also known as all of the following EXCEPT:
    a. T1 recovery
    b. Spin lattice
    c. Longitudinal recovery or relaxation
    d. Spin-spin

Answer 13

d. Spin-spin

Question 14

56. T2 relaxation is also known as:
    a. T1 recovery
    b. Spin lattice
    c. Longitudinal recovery or relaxation
    d. Spin-spin

Answer 14

d. Spin-spin

Question 15

57. T2 relaxation is also known as all of the following EXCEPT:
    a. T2 decay
    b. Spin lattice
    c. Spin-spin
    d. Transverse relaxation

Answer 15

b. Spin lattice

Question 16

58. T1 relaxation tim eis define as when:
    a. 76% of the longitudinal magnetisation has regrown
    b. 63% of the longitudinal magnetisation has regrown
    c. 63% of the transverse magnetisation has regrown
    d. 76% of the transverse magnetisation has regrown

Answer 16

b. 63% of the longitudinal magnetisation has regrown

Question 17

59. T2 relaxation tim ei sdefined as when:
    a. 76% of the longitudinal magnetisation has regrown
    b. 63% of the longitudinal magnetisation has regrown
    c. 63% of the transverse magnetisation has regrown
    d. 76% of the transverse magnetisation has regrown

Answer 17

c. 63% of the transverse magnetisation has regrown

Question 18

60. Images acquired with a spin echo pulse sequence having a SHORT TR and TE values yield images known as (Figure D.1):
    a. T1W1
    b. T2WI
    c. PDWI
    d. Diffusion images

Answer 18

a. T1W1

(Figure D.1):

Question 19

61. Images acquired with a spin echo pulse sequence having LONG TR and TE values yield image known as (Figure D.1):
    a. T1W1
    b. T2WI
    c. PDWI
    d. Diffusion images

Answer 19

b. T2WI

(Figure D.1):

Question 20

62. Images acquired with a spin echo pulse sequence having LONG TR an SHORT TE values yield images known as (Figure D.1):
    a. T1W1
    b. T2WI
    c. PDWI
    d. Diffusion images

Answer 20

c. PDWI

(Figure D.1):

Question 21

63. Spin density is another term for (Figure D.1):
    a. Nuclear density
    b. Spin density
    c. Proton density
    d. b and c

Answer 21

b. Spin density

(Figure D.1):

Question 22

64. Spin density is determined by the (Figure D.1):
    a. Amount of excess spins in the low energy state at equilibrium
    b. Amount of transverse magnetisation at the time the echo is sampled
    c. T1/T2
    d. Amount of excess spins in the high energy state equilibrium

Answer 22

a. Amount of excess spins in the low energy state at equilibrium

(Figure D.1):

Question 23

65. Gradient echo (steady-state) sequences acquired with short TR and flip angle combinations along with a moderately long TE yield images with (Figure D.1):
    a. T1 contrast
    b. T2 contrast
    c. PF contrast
    d. T2* contrast

Answer 23

d. T2* contrast

Question 24

66. T2 + T2’ equals (Figure D.1):
    a. T1
    b. T2
    c. PD
    d. T2*

Answer 24

d. T2*

Question 25

67. The LOGICAL gradient that is used for slice selection for the acquisition of an axial slice is the: a. x b. y c. z d. A combination of gradients

Answer 25

c. z

Question 26

68. The PHYSICAL gradient that is used for slice selection for the acquisition of an axial slice is the: a. x b. y c. z d. A combination of gradients

Answer 26

c. z

Question 27

69. The LOGICAL gradient that is used for the lice selection for the acquisition of a sagittal slice is the: a. x b. y c. z d. A combination of gradients

Answer 27

c. z

Question 28

70. The PHYSICAL gradient that is used for slice selection for the acquisition of a sagittal slice is the: a. x b. y c. z d. A combination of gradients

Answer 28

a. x

Question 29

71. The LOGICAL gradient that is used for phase encoding for the acquisition of an axial slice of the abdomen is the: a. x b. y c. z d. A combination of gradients

Answer 29

b. y

Question 30

72. The LOGICAL gradient that is used for phase encoding for the acquisition of an axial slice of the head is the: a. x b. y c. z d. A combination of gradients

Answer 30

b. y

Question 31

73. The PHYSCIAL gradient that is sued for phase encoding for the acquisition of an axial slice of the abdomen is the: a. x b. y c. z d. A combination of gradients

Answer 31

b. y

Question 32

74. The PHYSICAL gradient that is used for phase encoding for the acquisition of an axial slice of the head is: a. x b. y c. z d. A combination of gradients

Answer 32

a. x

Question 33

75. The receiver bandwidth is related to the slope of the: a. Frequency-encoding gradient b. Phase-encoding gradient c. Slice-selecting gradient d. Transmitting gradient

Answer 33

a. Frequency-encoding gradient

Question 34

76. Following a 90° RF pulse, the signal that is created is called: a. Spin echo b. Gradient echo c. Free induction decay d. FRE

Answer 34

c. Free induction decay

Question 35

77. T2* is a result of dephasing due to a tissue's T2 time and: a. T1 b. Susceptibility, inhomogeneities, and chemical shift c. Molecular weight d. a and b

Answer 35

b. Susceptibility, inhomogeneities, and chemical shift

Question 36

78. The peak signal strength of a spin echo is less than the initial signal strength of the free induction decay because of: a. T1 relaxation b. T2* decay c. Spin density changes d. T2 relaxation

Answer 36

d. T2 relaxation

Question 37

79. An example of a dipole is: a. A hydrogen nucleus b. A bar magnet c. The earth d. a, b, and c

Answer 37

d. a, b, and c

Question 38

80. A vector has both direction and: a. Purpose b. Current c. Magnitude d. A fractional equivalent force

Answer 38

c. Magnitude

Question 39

81. Hydrogen nuclei have a magnetic moment because they possess a property called: a. Inversion b. Flux c. Spin d. Resonance

Answer 39

c. Spin

Question 40

82. When placed in a large static magnetic field, hydrogen nuclei: a. Align with the magnetic field b. Align in either a parallel or antiparallel position c. Oscillate d. Relax

Answer 40

b. Align in either a parallel or antiparallel position

Question 41

83. Spins aligned in the antiparallel direction are in: a. An expanded energy state b. A resonant condition c. A high-energy state d. A constant sate of flux

Answer 41

c. A high-energy state

Question 42

84. During thermal equilibrium, the spin excesses of individual hydrogen nuclei add to form: a. A rotating vector b. An oscillating vector c. A varying vector d. A net magnetisation vector

Answer 42

d. A net magnetisation vector

Question 43

85. The formula that describes the relationship between the static magnetic field and the precessional frequency of the hydrogen protons is the: a. Helholtz relationship b. Nyquist theorem c. Larmor equation d. Bloch equation

Answer 43

c. Larmor equation

Question 44

86. To calculate the precessional frequency, the strength of the static magnetic field is multiplied by a constant known as the: a. Gyromagnetic ratio b. Tau c. Alpha- 1 d. Linear attenuation coefficient

Answer 44

a. Gyromagnetic ratio

Question 45

87. The condition reached within a few seconds of hydrogen being paced in a magnetic field is described as: a. Resonance b. Free induction decay c. Phase coherence d. Thermal equilibrium

Answer 45

d. Thermal equilibrium

Question 46

88. During thermal equilibrium, the individual protons precess: a. At the same frequency b. In phase c. Out of phase d. Slower

Answer 46

c. Out of phase

Question 47

89. In order for energy to transfer between systems, the two systems must be at the same: a. Phase location b. Energy level c. Mass d. Resonant frequency

Answer 47

d. Resonant frequency

Question 48

90. Assuming a TR sufficient for full recovery of longitudinal magnetisation, maximum signal is produced in the receiver coil when the net magnetisation is tipped: a. 180° b. 90° c. Away from the z axis d. Through the transverse plane

Answer 48

b. 90°

Question 49

91. In relation to the static magnetic field (B₀), the RF field (B₁), is orientated: a. Parallel b. Perpendicular c. At 180° d. At 45°

Answer 49

b. Perpendicular

Question 50

92. The RF energy used in MRI is classified as: a. Electromagnetic radiation b. Ionising radiation c. Nonradiation energy d. Investigational

Answer 50

a. Electromagnetic radiation

Question 51

93. Immediately on the application of the 90° pulse, the precessing protons: a. All flip to the high energy state b. Tip into the transverse plane c. Begin to precess in phase d. a and b

Answer 51

c. Begin to precess in phase

Question 52

94. The MR signal is produced by magnetisation: a. Out of phase b. In the longitudinal direction c. Decayed d. In the transverse plane

Answer 52

d. In the transverse plane

Question 53

95. Frequency can be defined by the: a. Rate of phase change per unit time b. Phase/2 c. Fourier equation d. Amplitude of the signal

Answer 53

a. Rate of phase change per unit time

Question 54

96. Gradient magnetic fields are used to: a. Improve the SNR b. Spatially encode the data c. Transmit the RF pulse d. Control the image contrast

Answer 54

b. Spatially encode the data

Question 55

97. Slice thickness is controlled by: a. Length of the gradient field b. Slope of the gradient c. Receiver bandwidth d. a and b

Answer 55

b. Slope of the gradient

Question 56

98. The physical gradient along the bore of a superconducting magnet is the: a. x gradient b. x, y gradient c. y gradient d. z gradient

Answer 56

d. z gradient

Question 57

99. To produce a sagittal slice, the physical gradient used during the excitation pulse is the: a. z gradient b. y gradient c. x gradient d. a and b

Answer 57

c. x gradient

Question 58

100. The gyromagnetic ratio for hydrogen is: a. 63.86 MHz/T b. 42.6 MHz/T c. 1 G/cm d. 4 W/kg

Answer 58

b. 42.6 MHz/T

Question 59

101. In a 0.5-T imager, the precessional frequency of hydrogen is approximately: a. 63.86 MHz b. 42.6 MHz c. 21.3 MHz d. 0.5 MHz

Answer 59

c. 21.3 MHz

Question 60

102. The amount of RF energy necessary to produce a 45° flip angle is determined by the: a. Coil being used b. Amplitude (power) and duration of the RF pulse c. Strength of the external magnetic field d. All of the above

Answer 60

d. All of the above

Question 61

103. The gradient that varies in amplitude with each TR is the: a. Phase-encoding gradient b. Frequency-encoding gradient c. Slice selecting gradient d. a and b

Answer 61

a. Phase-encoding gradient

Question 62

104. The gradient that is on during the sampling of the echo is the: a. Phase-encoding gradient b. Frequency-encoding gradient c. Slice selecting gradient d. a and b

Answer 62

b. Frequency-encoding gradient

Question 63

105. K-space is: a. The image in its natural state b. A negative of an MR image c. The raw data from which an MR image is created d. What comes after J space

Answer 63

c. The raw data from which an MR image is created

Question 64

106. Multiple coil elements combined with multiple receiver channels is a: a. Quadrature coil b. Surface coil c. Linear coil d. Phased array coil

Answer 64

d. Phased array coil