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MRI Flashcards

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1
Q

Spectroscopic study of the magnetic properties of nucleus of the atom

A

Nuclear magnetic resonance

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2
Q

Energy coupling that causes the individual nuclei, when placed in a strong external magnetic field, to selectively absorb and later release energy unique to those nuclei and their surrounding environment

A

Resonance

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3
Q

Fundamental property of matter; it is generated by moving charges, usually electrons

A

Magnetism

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4
Q

Magnetic properties of materials result from the

A

Organization and motion of the electrons in either a random or a nonrandom alignment of magnetic “domains” which are the smallest entities of magnetism

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5
Q

Origin of the magnetic field lines

A

North pole

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6
Q

Return of magnetic field lines

A

South pole

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7
Q

Can be conceptualized as the number of magnetic lines of force per unit area, which decreases roughly as the inverse square of the distance from the source

A

Magnetic field strength/magnetic flux density

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8
Q

Earth’s magnetic field is

A

0.05 mT

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9
Q

magnetic field strength and field density are dependent in the

A

Amplitude of current and number of coil turns

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10
Q

Magnetic field lines extending beyond the concentrated field are known as

A

Fringe fields

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11
Q

Performance criteria for magnet type

A

Field strength, temporal stability, field homogeneity

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12
Q

Characteristic of certain metals that when maintained at extremely low temperatures, exhibit no resistance to electric current

A

Superconductivity

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13
Q

Replenishment of the liquid helium must occur continuously, because if the temperature rises above a critical value, the loss of superconductivity will occur and resistance heating of wires will boil the helium, resulting in a

A

Quench

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14
Q

Common superconductive magnets have field strengths of

A

1.5 to 3 T

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15
Q

Magnetic field strength used for research application

A

4-7 T

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16
Q

Interact with the main magnetic field to improve homogeneity (minimal variation of the magnetic flux density) over the volume used for patient imaging

A

Shim coils

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17
Q

Exist within the main bore of the magnet to transmit energy to the patient as well as to receive returning signals

A

Radiofrequency coils

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18
Q

Contained within the main bore to produce linear variation if the magnetic field strength across the useful magnet volume

A

Gradient coils

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19
Q

Describes the extent to which a material becomes magnetized when placed in a magnetic field

A

Magnetic susceptibility

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20
Q

Have slightly negative susceptibility and oppose the applied magnetic field, because of paired electrons in the surrounding electron orbitals

A

Diamagnetic elements

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21
Q

calcium, water and most organic materials are examples of

A

Diamagnetic materials

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22
Q

With unpaired electrons, have slightly positive susceptibility and enhance the local magnetic field, but they have no measurable self magnetism

A

Paramagnetic materials

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23
Q

Molecular oxygen, deoxyhemoglobin, methemoglbin and gadolinium -based contrast agents are examples of

A

Paramagnetic materials

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24
Q

Superparamagnetic materials that augment the external magnetic field substantially. Exhibits self-magnetism

A

Ferromagnetic

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25
Q

Iron, cobalt and nickel are examples of

A

Ferromagnetic materials

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26
Q

Depleting magnetic materials

A

Diamagnetic

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27
Q

Augmenting magnetic materials

A

Paramagnetic materials

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28
Q

If there are equal number of protons and neutrons in the nucleus, the nuclear magnetic moment is

A

Essentially zero

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29
Q

If the number of protons and neutrons are unequal, the nuclear magnetic moment is

A

Generated

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30
Q

Principal focus for generating MR signals

A

Nucleus of hydrogen atom, the proton

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31
Q

Under the influence of an applied external magnetic field, the protons assume a nonrandom alignment in 2 possible orientations

A

Parallel and antiparallel

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32
Q

Between parallel and antiparallel directions, at equilibrium, a slight majority exists in the

A

Low energy parallel direction

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33
Q

Protons also experience a torque in a perpendicular direction from the applied magnetic field that causes

A

Precession

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34
Q

Precession occurs at what direction of frequency

A

Angular frequency

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35
Q

Describes the dependence between the magnetic field and the angular precessional frequency

A

Larmor equation

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36
Q

Two frames of reference in the applied magnetic field

A

Laboratory frame and rotating frame

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37
Q

Stationary reference frame from the observer’s point of view

A

Laboratory frame

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38
Q

A spinning axis system whereby the x-y axes rotate at an angular frequency equal to the Larmor frequency

A

Rotating frame

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39
Q

Slightly higher precessional frequency is observed as a slow ______ rotation

A

Clockwise rotation

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40
Q

Slightly lower precessional frequency is observed as a slow _______ rotation

A

Counterclockwise

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41
Q

Component of the magnetic moment parallel to the applied magnetic field

A

Longitudinal magnetization

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42
Q

Component of the magnetic moment perpendicular to x-y plane

A

Transverse magnetization

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43
Q

Corresponds to the energy separation between the protons in the parallel and antiparallel directions

A

Resonance frequency

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44
Q

Considers the RF energy as photons (quanta) instead of waves

A

Quantum mechanics model

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45
Q

Result of angular displacement of the longitudinal magnetisation vector from the equilibrium position

A

Flip angles

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46
Q

Term describing the release of energy back to lattice

A

Spin-lattice relaxation

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47
Q

T1 time is strongly dependent on the

A

Physical characteristics of the tissues and their associated hydration layers

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48
Q

Longer T1 relaxation time is taken from

A

Solid organs, unstructured tissues and fluids in bulk water

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49
Q

Shorter T1 relaxation time is achieved with

A

Structures and moderately sized proteins and fatty tissues

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50
Q

What influences T1 and T2 relaxation

A

Molecular motion, size and interactions

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51
Q

T1 values are _______ for higher field strength magnets while T2 values are unaffected

A

Longer

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52
Q

Period between B1 excitation pulses

A

Time of repetition (TR)

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53
Q

Time between excitation pulse and the appearance of the peak amplitude of an induced echo, which is determined by applying a 180 degree RF inversion pulse or gradient pplariry reversal at a time equal to TE/2

A

Time of echo

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54
Q

Time between an initial inversion/excitation (180 degrees) RF pulse that produces maximum tissue saturation and a 90-degree readout pulse

A

Time of inversion

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55
Q

Produced damped sinusoidal electronic signal from rotating at the Larmor frequency

A

Free induction decay

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56
Q

State of tissue magnetization from equilibrium conditions

A

Saturation

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57
Q

At equilibrium, the protons in a material are saturated or unsaturated?

A

Unsaturated

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58
Q

Occurs because the repetition time between excitation pulses does not allow for full return to equilibrium, therefore the Mz amplitude for the next RF pulse is reduced

A

Partial saturation

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59
Q

Describes the excitation of the magnetized protons in a sample with a 90 degree pulse converts Mz into Mzy and creates the largest phase coherent transverse magnetization that immediately begins to decay at a rate described by T2* relaxation

A

Spin echo

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60
Q

It is proportional to the difference in signal intensity between adjacent pixels in an image, corresponding to different voxels in the patient

A

Contrast

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61
Q

Sequence designed to produce contrast chiefly based on the T1 characteristic of tissues with de-emphasis of T2 and proton density contributions to the signal

A

T1-weighted SE sequence

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62
Q

Most intense signal in T1

A

Fat

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63
Q

Relies mainly on differences in the number of magnetized protons per unit volume of tissue

A

Proton density contrast weighting

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64
Q

Sequence that achieves the highest overall signal intensity and the largest signal to noise ratio; however, the image contrast is relatively low and therefore the contrast-to-noise ratio is not necessarily larger than achievable with T1 or T2 contrast weighting

A

Proton density weighting

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65
Q

Generated from the second echo produced by a second 180 degree pulse of a long TR spin echo pulse sequence, where the first echo is proton density weighted with short TE

A

T2 weighting

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66
Q

Emphasizes T1 relaxation times of the tissues by extending the amplitude of the longitudinal recovery by a factor of two

A

Inversion recovery

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67
Q

Delay between the excitation pulse and conversion to transverse magnetization of the recovered longitudinal magnetization

A

Inversion recovery

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68
Q

Pulse sequence that uses a very short T1 and magnitude signal processing, where Mz signal amplitude is always positive

A

Short tau inversion recovery

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69
Q

Reduces distracting fat signals and chemical shift artifacts

A

Short tau inversion recovery

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70
Q

Reduces CSF signal and other water-bound anatomy in the MR image by using a T1 selected at or near bounce point of CSF to permit better evaluation of the surrounding anatomy

A

Fluid attenuating inversion recovery

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71
Q

Downsides of spin echo and inversion recovery SE sequences

A

Less sensitive to magnetic field inhomogeneities, magnetic susceptibilities and generally gives high SNR and CNR, relatively long TR and corresponding long acquisition times

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72
Q

Uses a magnetic field gradient applied in one direction and then reversed to induce the formation of an echo, instead of 180 degree inverse pulse

A

Gradient echo

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73
Q

Not a true spin echo but a purposeful dephasing and rephasing of the FID

A

Gradient echo

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74
Q

Magnetic field inhomogeneities and tissue susceptibilities caused by paramagnetic or diamagnetic tissues or contrast agents are emphasized in

A

Gradient echo imaging

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75
Q

Magnetic field gradient induces the formation of an _____ Instead of 180-degree RF pulse

A

Echo

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76
Q

Transverse magnetization spins are ______ with an applied gradient of one polarity

A

Dephased

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77
Q

Transverse magnetization spins are _____ with the gradient reversed in polarity

A

Rephased

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78
Q

Transverse magnetization is higher/lower? For small flip angles compared to larger flip angles

A

Higher

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79
Q

A relatively long TE tends to emphasize the differences between

A

T2* and T2

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80
Q

Indicates the timing of the RF pulse with the dephasing and rephasing implemented by reversal of gradient polarity to generate an echi at a selectable time TE for the frequency encode gradient, where identification of proton position based upon frequency is performed

A

Coherent GE

81
Q

Applied and incrementally changed for each TR to identify proton position in the direction perpendicular to the frequency encode gradient based upon phase changes of the protons after the PEG is turned off

A

Phase encode gradient

82
Q

Gradient that generates the echo from the free induction decay plus the stimulated echo from the previous RF pulse

A

Frequency encode gradient

83
Q

T2* influence can be reduced by using a long TR, or by

A

Incoherent, “spoiled” gradient echo techniques

84
Q

Downsides of spoiled GE techniques

A

Increased sensitivity to other artifacts such as chemical shift and magnetic field inhomogeneities as well as lower SNR

85
Q

Sequence that emphasizes acquisition of only the stimulated echo, which arises from the previous RF pulse and appears during the next RF pulse at a time equal to 3 x TR

A

Steady state free precession

86
Q

In steady state free precession, there are two TE values

A

Actual TE and Effective TE

87
Q

Time between the peak stimulated echo and the next excitation pulse in ssfp

A

Actual TE

88
Q

Time from the echo and RF pulse that creates its free induction decay

A

Effective TE

89
Q

For GE acquisition in the realm of short TR, persistent transverse magnetization produces two signals

A
  • FID produced from the RV pulse just applied and

- Stimulated echo from the residual transverse magnetization

90
Q

Uses both gradient and stimulated echo to produce a T2/T1 weighing with symmetrically applied gradients in 3 directions

A

Balanced SSFP

91
Q

2 important properties of magnetic gradients are:

A

Gradient field strength

Slew rate

92
Q

Determined by its peak amplitude and slope (change over distance), and typically range 1 to 50 Tm/m

A

Gradient field strength

93
Q

Time to achieve the peak magnetic field amplitude

A

Slew rate

94
Q

Typical slew rates of gradient fields are from

A

5-250 mT/m/ms

95
Q

Induced in nearby conductors such as adjacent RF coils and the patient, which produce magnetic fields that oppose the gradient field and limit the achievable slew rate

A

Eddy currents

96
Q

Middle of the gradient is called _____, where there is no change in the field strength or precessional frequency

A

Null

97
Q

It is the range of frequencies over the FOV

A

Frequency bandwidth

98
Q

Frequency BW per pixel is BW divided by the

A

Number of discrete samples

99
Q

Relationship of gradient strength and frequency BW across the FOV is dependent/independent of the main magnet field strength

A

Independent

100
Q

Determines the slice location of protons in the tissues that absorb energy

A

Slice select gradient

101
Q

SNR is inversely proportional to the receiver BW, therefore _____ are preferred

A

Narrow BW and low gradient strength

102
Q

It is applied simultaneously with s RF pulse of a known BW to create proton excitation in a single plane with a known slice thickness, and to localize signals orthogonal to the gradient

A

Slice select gradient

103
Q

Applied in a direction perpendicular to the SSG, along the logical x-axis, during the evolution and decay of the induced echo

A

Frequency encode gradient

104
Q

Applied before frequency encode gradient and slice select gradient. It produces a spatially dependent variation in angular frequency of the excited spins for a brief duration, and generates a spatially dependent variation in phase when the spins return to the Larmor frequency

A

Phase encode gradient

105
Q

MR Data are initially stored in the _____ matrix, the “frequency domain” repository

A

K-space

106
Q

It describes a 2 dimensional matrix of positive and negative spatial frequency values, encoded as complex numbers

A

K-space

107
Q

K-space matrix is divided into 4 quadrants, with the origin at the center representing frequency= 0. Frequency domain data are encoded in the kx direction by

A

Frequency encode gradient

108
Q

Frequency domain data are encoded in ky direction by _____ in most image sequences

A

Phase encode gradient

109
Q

Maximal useful frequency

A

Nyquist frequency

110
Q

A 90 degree flip angle produces the largest

A

Transverse magnetization

111
Q

Spatial domain representation are produced by

A

Inverse Fourier Transform decodes

112
Q

Axial uses what coils

A

Z-axis coils

113
Q

Coronal uses what coils

A

Y-axis coil

114
Q

Sagittal uses what coils

A

X-axis coils

115
Q

For a standard spin echo sequence, the relevant parameters are the

A

TR, number of excitations (NEX)

used for averaging identical repeat cycles

116
Q

Tecniques that use multiple PEG steps in conjunction with multiple 180 degree refocusing RF pulses to produce an echo train length with corresponding digital data acquisitions per TR interval

A

Fast pulse sequences

117
Q

Determined when the central views in k-space are acquired, which are usually the first echoes and subsequent echoes are usually spaced apart via increased PEG strength with the same echo spacing time

A

Effective echo time

118
Q

Optimizes SNR by acquiring rhe low-frequency information with the early echoes (lowest amount of T2 decay) and the high-frequency, peripheral information with late echoes, where the impact on overall image SNR is lower

A

Phase re-ordering

119
Q

Technique that has the advantage of spin echo image acquisition, namely immunity from external magnetic field inhomogeneities, with faster acquisition time

A

Fast pulse sequences

120
Q

Also known as turbo spin echo or “RARE” (rapid acquisition with refocused echoes)

A

Fast spin echo

121
Q

Pulse sequence that is similar to a standard echo sequence with a readout gradient reversal substituting for the 180 degree pulse

A

Gradient echo acquisition

122
Q

Technique that provides extremely fast imaging time

A

Echo planar image aquisition

123
Q

Sequence that combines the initial spin echo with a series of GEs, followed by an RF rephasing (180 degrees) pulse, and the pattern is repeated until k-space is filled

A

GRASE (gradient and spin echo)

124
Q

Another method of k-space filling where the lower strength phase encode gradients are applied first, filling the center of k-space when the echoes have their highest amplitude. This type of filling is also important for fast GE techniques

A

Centric k-space filling

125
Q

Method that fill k-space similarly to centric filling, except the central lines are filled when important events occur during the sequence, in situations such as contrast-enhanced angiography

A

Keyhole filling

126
Q

An alternate method of filling the k-space radially, which involves the simultaneous oscillation of equivalent encoding gradients to sample data points during echo formation in a spiral, starting at the origin (the center of k-space) and spiraling outward to the periphery in the prescribed acquisition plane

A

Spiral filling

127
Q

Technique that fills k-space by using the response of multiple recieve RF coils that are couples together with independent channels, so that data can be acquired simultaneously

A

Parallel imaging

128
Q

Requires the use of a broadband, non-selective or slab-selective RF pulse to excite a large volume of protons simultaneously

A

Three-dimensional image acquisition (volume imaging)

129
Q

Also known as the number of excitations

A

Signal averaging

130
Q

Defines the range of frequencies to which the detector is tuned during the application of the readout gradient

A

Receiver bandwidth

131
Q

Often a result of high-velocity signal loss, in which protons in the flowing blood move out of the slice during echo reformation, causing a lower signal

A

Low signal intensities (flow voids)

132
Q

This causes flow voids by causing a dephasing of protons in the blood with a resulting loss of tissue magnetization in area turbulence

A

Flow turbulence

133
Q

Pulse sequences to produce “black blood” can be very useful in

A

Cardiac and vascular imaging

134
Q

A typical black blood pulse sequence uses a ______ method whereby a non-selective 180 degree RF pulse is initially applied, inverting all protons in the body, and is followed by a selective 180-degree RF pulse that restores the magnetization in the selected slice

A

Double inversion recovery method

135
Q

A process that causes increased signal intensity due to flowing protons; it occurs during imaging of a volume of tissues

A

Flow-related enhancement

136
Q

A phenomenon that causes flow to exhibit increased signal on even echoes in a multiple-echo image acquisition

A

Even-echo rephasing

137
Q

Unsaturated blood exhibits the greatest signal if the blood velocity is increased or decreased?

A

Increased

138
Q

Undesirable Flow-related enhancement and motion artifacts are eliminated with the use of

A

Presaturation pulses

139
Q

MRA technique that relies on tagging of blood in one region of the body and detecting it in another

A

Time-of-flight technique

140
Q

MR angiography techniques to create images of vascular anatomy include what 2 techniques

A

Time-of-flight and phase contrast angiography

141
Q

Often used for two-dimensional image acquisition is ______ that produces relatively poor anatomic contrast, yet provides a high-contrast “bright blood” signal

A

GRASS or FISP

142
Q

Detects the largest signal along a given ray thru the volume and places this value in the image

A

Maximum intensity projection algorithm

143
Q

Relies on the phase change that occurs in moving protons such as blood

A

Phase contrast angiography

144
Q

Degree of phase shift in phase contrast angiography is directly related to the

A

Velocity encoding time

145
Q

Moving protons are subjected to gradients, the amount of phase dispersion is not compensated. This phase dispersal can cause ghosting in images. Rephasing of photons is done by

A

Gradient moment nulling

146
Q

Produces multiple T2*- weighted images of the head before the application of the stimulus

A

Blood oxygen level dependent (BOLD)

147
Q

Relates to the random motion of water molecules in tissues

A

Diffusion

148
Q

Use strong MR gradients applied symmetrically about the refocusing pulse to produce signal differences based on the mobility and directionality of water diffusion

A

Diffusion weighted imaging sequences

149
Q

Sensitive indicator for early detection of ischemic injury

A

Diffusion weighted imaging

150
Q

Areas of stroke in DWI show

A

Drastic reduction in the diffusion coefficient compared with nonischemic tissues

151
Q

Challenges in DWI include

A

Extreme sensitivity to motion

Eddy currents

152
Q

Result of selective observation of the interaction between protons in free water molecules and protons contained in the macromolecules of a protein

A

Magnetization transfer contrast

153
Q

This technique is used for anatomic MRI of the heart, eye, multiple sclerosis, knee cartilage and general MRA

A

Magnetization transfer contrast

154
Q

Artifacts caused by nonferromagnetic conducting materials produce field distortions that disturb the local magnetic field, this pulse sequence reduces these artifacts

A

Partial compensation by spin echo

155
Q

This echo sequence accentuates the artifacts caused by nonferromagnetic materials

A

Gradient refocused echo sequence

156
Q

Ratio of the induced internal magnetization in a tissue to the external magnetic field

A

Susceptibility artifacts

157
Q

Most common susceptibility changes occur at

A

Tissue-air-interfaces

158
Q

Causes image distortions by mis-mapping anatomy

A

Gradient field artifacts

159
Q

Produces variations in uniformity across the image caused by RF excitation variability, attenuation, mismatching and sensitivity falloff with distance

A

RF surface coils

160
Q

Technique to mitigate cross-excitation by reordering slices into two groups with gaps

A

Slice interleaving

161
Q

This artifact mostly occurs along the phase encode direction, as adjacent phase encoding measurement in k-space are separated by a TR Interval that can last 3000ms or longer

A

Motion artifacts

162
Q

Motion compensation method that signal acquisition at a particular cyclic location synchronizes the phase changes applied across the anatomy

A

Cardiac and respiratory gating

163
Q

Motion compensation method that reduce artifacts of random motion by making displaced signals less conspicuous relative to stationary anatomy

A

Signal averaging

164
Q

What is more susceptible to motion, short or long TE spin echo sequence?

A

Long TE sequence

165
Q

Motion artifact compensation that help rephase protons that are dephased due to motion

A

Gradient moment nulling

166
Q

Helps reduce flow artifacts from inflowing protons, as well as other patient motions that occur in the periphery

A

Presaturation pulses applied outside the imaging region

167
Q

To identify and remove those sequences contributing to motion, without deleteriously affecting the image

A

Multiple redundant sampling in the center of k-space

168
Q

Refers to the resonance frequency variations resulting from intrinsic magnetic shielding of anatomic structures

A

Chemical shift artifacts

169
Q

Chemical shift artifact is more severe for higher or lower field strength magnets?

A

Higher field strength magnets

170
Q

Chemical shift occurrence is more severe for lower or higher gradient strengths?

A

Lower gradient strengths

171
Q

Occur when data is acquired without consideration of physiologic periodicity

A

Motion artifact

172
Q

Artifacts that occur with the GE images, resulting from rephasing and dephasing of the echo in the same direction relative to the main magnetic field

A

Chemical shift artifacts of the second kind

173
Q

Also known as Gibbs phenomenon, occurs near sharp boundaries and high-contrast transitions in the image, and appears as multiple, regularly spaced parallel bands of alternating bright and dark signal that slowly fades with distance

A

Ringing artifacts

174
Q

Artifacts that are more likely for smaller digital matrix sizes. Commonly occurs at skull/brain interfaces, where there is a large transition in signal amplitude

A

Ring artifact

175
Q

Artifact that results from the mismapping of anatomy that lies outside of the FOV but within the slice volume

A

Wraparound artifacts

176
Q

Artifact that arise from the finite size of the voxel over which the signal is averaged. It results in a loss of detail and spatial resolution

A

Partial volume artifacts

177
Q

Method to measure tissue chemistry by recording and evaluating signals from metabolites by identifying metabolic peaks caused by frequency shifts (in parts per million) relative to a frequency standard

A

Magnetic resonance spectroscopy

178
Q

Used to evaluate serial evaluation of biochemical changes in tumors, analyzing metabolic disorders, infections and diseases, as well as evaluation of therapeutic oncology treatments for tumor recurrence versus radiation damage

A

MR spectroscopy

179
Q

Single voxel MRS sampling areas, covering a volume of about 1cm3 are delineated by

A

Stimulated echo acquisiton mode (STEAM) or

Point Resolved Spectroscopy (PRESS)

180
Q

Method that uses a 90 degree excitation pulse and 90 degree refocusing pulse to collect the signal in conjunction with gradients to define each dimension of voxel

A

STEAM (stimulated echo acquisition mode)

181
Q

Sequence that uses a 90-degree excitation and 180-degree refocusing pulse in each direction

A

Point resolved spectroscopy (PRESS)

182
Q

Active or passive magnetic field devices that are used to adjust the main magnetic field and to improve the homogeneity in the sensitive central volume of the scanner

A

Shim coils

183
Q

Wire conductors that produce a linear superimposed gradient magnetic field on the main magnetic target

A

Gradient coils

184
Q

Creates an oscillating secondary magnetic field formed by passing an alternating current thru a loop of wire

A

RF transmitter coils

185
Q

Encompass the total area of the anatomy of interest and yield uniform excitation and SNR over the entire imaging volume

A

volume coils

186
Q

Enhanced performance is obtained with a process known as _______, which enables the energy to be transmitted with the signals to be received by two pairs of coils oriented at right angles, either electronically or physically

A

Quadrature excitation and detection

187
Q

Used to achieve high SNR and high resolution when imaging anatomy near the surface of the patient, such as the spine

A

Surface coils

188
Q

Consisting of multiple coils and receivers are made of several overlapping loops, which extend the imaging FOV in one direction

A

Phased array coils

189
Q

With as many as N=32 elements allow for detection and encoding based upon the detection of a sensitivity map of the signals near the coil. There are used in parallel imaging

A

Multi-channel encoding coils

190
Q

Patients with pacemakers or ferromagnetic aneurysm clips must avoid fringe fields above ____ mT

A

0.5 mT

191
Q

Room containing the MRI system is typically lined by

A

Copper sheet walls and mesh windows

192
Q

Achieved by manipulating the main field peripherally with passive and active “shim” coils which exist in proximity to the main magnetic field

A

Field uniformity

193
Q

Area freely accessible to the general public, in essence everywhere outside the MR magnet area and building

A

Zone 1

194
Q

Represents the interface between zone 1 and zone 3— typically the reception area, where the patients are registered and MR screening questions take place

A

Zone 2

195
Q

Typically the reception area, comprised of the MR control room and computer room that only specific personnel can access, namely those specifically trained as MR personnel

A

Zone 3

196
Q

Represents the MR magnet room, and is always located within the confines of zone 3

A

Zone 4

197
Q

Have passed minimal safety and education training on MR safety issues and have a basic understanding of the effects of MR magnets, dangers of projectiles, effects of strong magnetic fields, etc

A

Level 1 MR personnel

198
Q

More extensively trained in the broader aspects of MR safety issues, for example, understanding the potential for thermal loading, burns, neuromuscular excitation and induced currents from gradients

A

Level 2 MR personnel

Physics (7 decks)

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