MRI board review
In a gradient echo pulse sequence, blood flow that receives the initial RF pulse produces what type of signal? A. High B. Low C. No signal
A. High
The X gradient alters the magnetic field strength along which axis? A. Horizontal axis B. Vertical axis C. Long axis D. Short axis
A. Horizontal axis
As blood flow velocity increases, the effects of time of flight phenomenon ____________. A. Increases B. Decreases C. Stays the same
A. Increases
As slice thickness decreases, the effects of time of flight phenomenon ___________. A. Increases B. Decreases C. Stays the same
A. Increases
As the echo time increases, the effects of time of flight phenomenon _______________. A. Increases B. Decreases C. Stays the same
A. Increases
The precessional frequency of hydrogen nuclei that experience increased magnetic field strength due to gradient coils __________. A. Increases B. Decreases C. Stays the same
A. Increases
When TR is increased, the effects of entry slice phenomenon ____________. A. Increases B. Decreases C. Stays the same
A. Increases
When slice thickness is decreases, the effects of entry slice phenomenon __________. A. Increases B. Decreases C. Stays the same
A. Increases
When the velocity of flow increases, the effects of entry slice phenomenon _____________. A. Increases B. Decreases C. Stays the same
A. Increases
Gradient echo pulse sequences that eliminate leftover transverse magnetization are said to be ______. A. incoherent B. coherent C. consistent D. inconsistent
A. incoherent
When the direction of blood flow is opposite the direction in which slices are acquired, the effects of entry slice phenomenon ___________. A. increase B. decrease C. stay the same
A. increase
As bandwidth decreases, sampling time _________. A. increases B. decreases C. stays the same
A. increases
When TR is increased, acquisition time ________. A. increases B. decreases C. stays the same
A. increases
When field of view decreases, spacial resolution _____. A. increases B. decreases C. stays the same
A. increases
When field of view is increased, signal to noise ratio _____. A. increases B. decreases C. stays the same
A. increases
When image matrix increases, acquisition time ______. A. increases B. decreases C. stays the same
A. increases
When image matrix is increased, spacial resolution ___________. A. increases B. decreases C. stays the same
A. increases
When magnetic field strength increases, signal to noise ratio ________. A. increases B. decreases C. stays the same
A. increases
When pixel size increases, signal to noise ratio ________. A. increases B. decreases C. stays the same
A. increases
When repetition time is increased, signal to noise ratio ____________. A. increases B. decreases C. stays the same
A. increases
When slice spacing increases, signal to noise ratio ________. A. increases B. decreases C. stays the same
A. increases
When slice thickness is increased, signal to noise ratio ___________. A. increases B. decreases C. stays the same
A. increases
When the amplitude of the phase encoding gradient increases, the amount of phase shift along the gradient ___________. A. increases B. decreases C. stays the same D. none of the above
A. increases
Gibbs artifact can be decreased by ___________ the number of phase encoding steps. A. increasing B. decreasing
A. increasing
The type of neoplasms in the head that enhance primarily due to the breakdown of the blood brain barrier are known as _______. A. intra axial neoplasms B. extra axial neoplasms C. acoustic neuromas D. none of the above
A. intra axial neoplasms
Neoplasms within the spinal cord are said to be located in which of the following locations? A. intramedullary B. extramedullary intradural C. extradural D. none of the above
A. intramedullary
Gadopentetate dimeglumine, also known as Magnevist, is based on what type of molecular structure? A. linear ionic B. linear nonionic C. macrocyclic ionic D. macrocyclic nonionic
A. linear ionic
In a T2 weighted image, CSF has a ________________ T2 relaxation time and therefore appears _______________. A. long, bright B. long, dark C. short, dark D. short, bright
A. long, bright
In a T2 weighted image, a long TE is used to _____________. A. maximize T2 effects B. minimize T2 effects C. maximize T1 effects D. minimize T1 effects
A. maximize T2 effects
Image data with high spatial resolution is stored in which area of k space? A. outer lines B. central lines C. negative lines only D. positive lines only
A. outer lines
In water, the hydrogen atom is bound with what other type of atom? A. oxygen B. nitrogen C. helium D. carbon
A. oxygen
When placed in an external magnetic field, low energy hydrogen nuclei point in which direction? A. parallel B. anti-paired C. anti-parallel D. perpendicular
A. parallel
Figure 5-1 is a diagram showing what type of pulse sequence? A. partial saturation B. spin echo C. inversion recovery D. gradient echo
A. partial saturation
The first whole body MRI scanner was a superconductive magnet with a field strength of __________. A. 3,000 gauss B. 5,000 gauss C. 10,000 gauss D. 15,000 gauss
B. 5,000 gauss
At a field strength of 1.0 tesla, the approximate T2 relaxation time of liver tissue is ________. A. 40 ms B. 50 ms C. 60 ms D. 70 ms
B. 50 ms
The precessional frequency of hydrogen at 1.5 Tesla is _____________. A. 42.6 MHz B. 63.86 MHz C. 63.86 KHz D. 21.28 KHz
B. 63.86 MHz
Gadolinium has how many unpaired electrons in its outermost orbit? A. 5 B. 7 C. 9 D. 11
B. 7
At a field strength of 1.0 tesla, the approximate T2 relaxation time for spleen tissue is _________. A. 60 ms B. 80 ms C. 90 ms D. 100 ms
B. 80 ms
At a field strength of 1.0 tesla, the approximate T2 relaxation time for white matter is ___________. A. 80 ms B. 90 ms C. 100 ms D. 140 ms
B. 90 ms
During slice selection, the Z gradient is used to select slices in which plane? A. Coronal B. Axial C. Sagittal D. None of the above
B. Axial
The chemical compounds used to bind the metallic ion in MRI contrast agents are known as ______. A. Hydrophilies B. Chelates C. Macrophanges D. None of the above
B. Chelates
To exist, magnets must have two poles, therefore they are commonly called _____________. A. vectors B. dipoles C. axis D. both A and C
B. dipoles
The number of picture elements used to make up an image is known as _________. A. contrast B. matrix C. signal to noise D. none of the above
B. matrix
In a T1 weighted image, a short TE is used to ______________. A. maximize T2 effects B. minimize T2 effects C. maximize T1 effects D. minimize T1 effects
B. minimize T2 effects
Contrast agents that stay electrically neutral in water and do not separate into ions are said to be ________. A. hydrophilic B. nonionic C. ionic D. none of the above
B. nonionic
The theorem that states that a frequency must be sampled at least twice in order to reproduce it reliably is known as the _____________. A. pathagarum theorem B. nyquist theorem C. larmor theorem D. fourier theorem
B. nyquist theorem
Image data along both the phase and frequency axis with the lowest signal amplitude is stored in which area of the K space? A. central lines B. outer lines C. positive lines only D. none of the above
B. outer lines
The area of K space that is filled with the steepest phase encoding gradient slopes is known as ________. A. central lines B. outer lines C. positive lines only D. none of the above
B. outer lines
Material that is weakly attracted to a magnetic field is said to be _______. A. electromagnetic B. paramagnetic C. ferromagnetic D. diamagnetic
B. paramagnetic
The homogeneity of the external magnetic field is measured in what type of unit? A. tesla per cm B. part per million C. gauss per meter D. megahertz
B. part per million
Figure 6-7 displays an example of what type of artifact? A. aliasing B. truncation C. chemical shift D. phase mismapping
B. truncation
In an echo planar pulse sequence, proton density weighting can be produced by which of the following techniques? A. applying a 180 degree RF pulse to pre-invert tissue before excitation B. using a short TE C. using a long TE D. using a 180 degree rephasing pulse
B. using a short TE
The QRS wave of the ECG represents which phase of the cardiac cycle? A. atrial systole B. ventricular systole C. ventricular diastole D. atrial diastole
B. ventricular systole
An artifact that is caused by an external radio frequency leak is known as _________. A. shading artifact B. zipper artifact C. starring artifact D. herringbone
B. zipper
The wire used in the main magnetic field of a superconducting magnet has its resistance removed by cooling it to a temp of ________. A. -452 degrees Fahrenheit B. 0 degrees Celsius C. 269 degrees Kelvin D. none of the above
A. -452 degrees Fahrenheit
In clinical MRI, permanent magnets can be produced to operate up to what field strength? A. .3 tesla B. .5 tesla C. 1.0 tesla D. 1.5 tesla
A. .3 tesla
The recommended whole body SAR limit for MR imaging is __________. A. 0.4 watts/kg B. 3.2 watts/kg C. 8 watts/kg D. 4 watts/kg
A. 0.4 watts/kg
In conventional spin echo pulse sequences, how many lines of k space are filled per TR? A. 1 B. 2 C. 4 D. 6
A. 1
In conventional spin echo pulse sequences, how many phase encoding steps are achieved per TR? A. 1 B. 128 C. 192 D. 256
A. 1
Typical peak velocities of the ascending aorta are usually within what range? A. 150-175 cm/sec B. 100-160 cm/sec C. 80-120 cm/sec D. 40-70 cm/sec
A. 150-175 cm/sec
At a field strength of 1.0 tesla, the approximate T1 relaxation time of fat is ________. A. 180 ms B. 270 ms C. 360 ms D. 390 ms
A. 180 ms
Which of the following TOF MRA sequences is most likely to saturate slow flow? A. 3D TOF B. 2D TOF
A. 3D TOF
At a field strength of 1.0 tesla, the approximate T2 relaxation time for muscle tissue is _________. A. 40 ms B. 70 ms C. 80 ms D. 100 ms
A. 40 ms
The precessional frequency of hydrogen at 1.0 Tesla is _______________. A. 42.6 MHz B. 63.86 MHz C. 25.48 MHz D. 21.28 KHz
A. 42.6 MHz
Which of the following vessels has the highest peak velocity? A. Ascending aorta B. Distal aorta C. Proximal carotid D. Basilar artery
A. Ascending aorta
Gd DTPA-BMA, also known as Omniscan, is bound by what chelate? A. Bismethylamide B. Diethylenetriamine pentaacetic acid C. Tertraazacyclododecane tetraacetic acid D. none of the above
A. Bismethylamide
Peripheral gating is a technique used to decrease what type of motion artifact? A. CSF pulsation motion B. Cardiac motion C. Swallowing D. Respiratory motion
A. CSF pulsation motion
During slice selection, the Y gradient is used to select slices in which plane? A. Coronal B. Axial C. Sagittal D. None of the above
A. Coronal
The inversion recovery pulse sequence that is used to suppress CSF in proton density and T2 weighted images is known as _____________. A. FLAIR B. STIR C. SSFP D. FISP
A. FLAIR
The amplitude of the phase and frequency encoding gradients determines the dimensions of what parameter? A. FOV B. TR C. TE D. NEX
A. FOV
The first magnetic resonance experiments with liquids were conducted by a group of scientists from Stanford University led by which of the following people? A. Felix Bloch B. Edward Purcell C. Otto Stern D. Paul Lauterbur
A. Felix Bloch
Entry slice phenomenon is most prominent in what slice of the area scanned? A. First slice B. Middle slice C. Last slice D. Affects all the same
A. First slice
What is another name for phase mismapping artifact? A. Ringing B. Aliasing C. Ghosting D. Truncation
C. Ghosting
Hazards to patients and technologists due to ferromagnetic objects within the scan room include which of the following? A. Metal projectiles B. Tissue burns C. Image artifacts D. None of the above
A. Metal projectiles
Which of the following patient injuries can be caused by improper placement of cardiac leads? A. Patient burns B. Temporary hearing loss C. Short term memory loss D. None of the above
A. Patient burns
MRI contrast agents known as T1 agents produce what type of contrast on T1 weighted images? A. Positive B. Negative
A. Positive
The ECG wave with the highest electrical amplitude is known as the _________. A. R wave B. Q wave C. T wave D. P wave
A. R wave
Coils that are used to transmit and receive radio frequencies are known as __________. A. RF coils B. shim coils C. gradient coils D. surface coils
A. RF coils
The calibration of transmit gain during the prescan process determines which factor? A. RF output necessary to produce a 90 degree flip angle B. the exact resonant frequency C. the necessary amount of signal needed to create an image D. none of the above
A. RF output necessary to produce a 90 degree flip angle
Figure 3-1 displays which type of relaxation curve? A. T1 relaxation curve B. T2 relaxation curve C. inversion recovery curve
A. T1 relaxation curve
The time it takes for a tissue's bulk longitudinal magnetization to return to 63% of its original value is known as ________________. A. T1 relaxation time B. T2 relaxation time C. T2* relaxation time D. none of the above
A. T1 relaxation time
A spin echo image with a short TR and a short TE is known as what type of image? A. T1 weighted image B. T2 weighted image C. proton density weighted image D. none of the above
A. T1 weighted image
MRI images that are based on the differences in longitudinal relaxation characteristics of tissues are known as _________. A. T1 weighted images B. T2 weighted images C. proton density weighted images D. transitional images
A. T1 weighted images
During cardiac gating, one R-R interval and a short TE is used to produce what type of image? A. T1 weighting B. T2 weighting C. proton density weighting D. none of the above
A. T1 weighting
In an echo planar pulse sequence, pre-inverting tissue with a 180 degree RF pulse before excitation produces what type of image weighting? A. T1 weighting B. T2 weighting C. proton density weighting D. none of the above
A. T1 weighting
Which of the following is the formula for determining scan time for a 3D FT pulse sequence? A. TR x NEX x phase steps x # of slices B. TR x NEX x phase steps C. NEX x TR x # of slices D. TR x phase steps x # of slices
A. TR x NEX x phase steps x # of slices
The speed at which blood flows through an excited slice and only receives one RF pulse is known as what type of phenomenon? A. Time of flight phenomenon B. Entry slice phenomenon C. Intra-voxel D. None of the above
A. Time of flight phenomenon
The direction of blood flow is an important factor in determining the effects of entry slice phenomenon. A. True B. False
A. True
To produce signal in a spin echo pulse sequence, blood flow must receive both the 90 degree and 180 degree RF pulse. A. True B. False
A. True
Blood flow that has randomly different velocities is known as what type of flow? A. Turbulent flow B. Laminar flow C. Vortex flow D. Stagnant flow
A. Turbulent flow
Which of the following is the formula that is used to calculate blood flow velocity? A. Velocity = flow volume / vessel area B. Velocity = vessel area / flow volume C. Velocity = flow volume + vessel area D. Velocity = vessel area - flow volume
A. Velocity = flow volume / vessel area
Possible biological effects associated with exposure to gradient magnetic fields at levels higher than that used in MRI include which of the following? A. Voltage produced in conductive tissue B. Hypertension C. Tissue burns D. None of the above
A. Voltage produced in conductive tissue
Specific absorption rate is expressed in units of what? A. Watts/kg B. Ohms/kg C. Amps/kg D. Watts/lb
A. Watts/kg
During the acquisition of axial images of the body with the phase direction A/P, frequency encoding is performed by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
A. X gradient
During the acquisition of axial images of the brain with the frequency direction A/P, phase encoding is conducted by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
A. X gradient
During the acquisition of coronal images with the frequency direction S/I, phase encoding is conducted by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
A. X gradient
Which of the following logical gradients is known as the frequency encoding gradient? A. X gradient B. Y gradient C. Z gradient
A. X gradient
The computer that performs the complex calculations necessary to reconstruct MRI images is known as the ___________. A. array processor B. RF amplifier C. gradient amplifier D. shim cabinet
A. array processor
The P wave of the ECG represents which phase of the cardiac cycle? A. atrial systole B. ventricular systole C. ventricular diastole D. atrial diastole
A. atrial systole
In clinical MRI, resistive magnets usually operate at what field strength? A. between 0.15-0.25 tesla B. between 0.5-1.5 tesla C. between 1.5-2 tesla D. over 2 tesla
A. between 0.15-0.25 tesla
The process during prescan that fine tunes the resonant frequency is known as __________. A. center frequency adjustment B. transmit gain adjustment C. receive attenuation adjustment D. impedance matching
A. center frequency adjustment
During a fast spin echo pulse sequence, which lines of k space are filled by the gradients performed closest to the effective TE? A. central lines B. outer lines C. negative lines only D. positive lines only
A. central lines
Image data along both the phase and frequency axis with the highest signal amplitude is stored in which area of K space? A. central lines B. outer lines C. positive lines only D. none of the above
A. central lines
The area of K space filled with the shallowest phase encoding slopes is known as _______________. A. central lines B. outer lines C. negative lines only D. none of the above
A. central lines
In clinical MRI, what method is used to prevent external radio frequency from affecting the MRI image? A. copper shielded room B. iron shielded magnet C. passive shimming D. none of the above
A. copper shielded room
Blood flow that travels in the opposite direction in which the slices are acquired is known as what type of flow? A. counter current flow B. vortex flow C. stagnant flow D. co-current flow
A. counter current flow
The artifact that is produced by overlapping radio frequency pulses in adjacent slices is known as ______. A. cross excitation artifact B. aliasing artifact C. truncation artifact D. phase mismapping artifact
A. cross excitation artifact
The magnitude of intra-voxel dephasing is dependent upon which factor(s)? A. degree of disruption in the flow B. echo time C. repetition time D. none of the above
A. degree of disruption in the flow
In a gradient echo pulse sequence, the use of an RF pulse to eliminate residual transverse magnetization is known as __________. A. digital RF spoiling B. frequency spoiling C. gradient spoiling D. none of the above
A. digital RF spoiling
In plane pixel size can be determined by which of the following methods? A. dividing the FOV by the number phase and frequency steps B. dividing the NEX by the FOV C. dividing the TR by the NEX D. dividing the TR by the slice thickness
A. dividing the FOV by the number phase and frequency steps
The image parameter that primarily affects T2 weighting is _____________. A. echo time B. inversion time C. repetition time D. none of the above
A. echo time
The time between the 90 degree RF pusle and the spin echo signal in a spin echo pulse sequence is known as ___________. A. echo time B. repetition time C. inversion time D. relaxation time
A. echo time
The series of 180 degree rephasing pulses in a fast spin echo pulse sequence is known as _________. A. echo train B. inversion train C. echo plane D. none of the above
A. echo train
The negatively charged component of an atom is called the ___________. A. electron B. proton C. negatron D. neutron
A. electron
Structures that are outside the blood brain barrier are said to be ___________. A. extra axial B. intra axial C. para axial D. none of the above
A. extra axial
The process that uses mathematical conversions to calculate the amplitude of individual frequencies is known as __________. A. fast fourier transformation B. free induction decay C. larmor equation D. none of the above
A. fast fourier transformation
The size of the area being displayed on an MR image is known as ________. A. field of view B. voxel size C. pixel size D. none of the above
A. field of view
The lines that represent the field of a magnet are known as __________. A. flux lines B. intensity lines C. induction lines D. faraday lines
A. flux lines
In a T1 weighted image, tissues with short T1 relaxation times produce what type of signal? A. high B. low C. intermediate D. none of the above
A. high
When the phase encoding gradient is activated, shallow slopes produce what type of signal amplitude? A. high B. low C. medium D. none of the above
A. high
When the phase encoding gradient is activated, steep slopes produce data with what type of spatial resolution? A. high B. low C. medium D. none of the above
A. high
Which of the following is an advantage of using a spin echo pulse sequence? A. high signal to noise ratio B. decreased resolution C. long scan times D. none of the above
A. high signal to noise ratio
In a T2 weighted image, tissues with long T2 relaxation time appear __________. A. hyperintense B. hypointense C. isointense D. none of the above
A. hyperintense
In a proton density weighted image, tissues with a high number of hydrogen nuclei appear __________. A. hyperintense B. hypointense C. isointense D. none of the above
A. hyperintense
On a T1 weighted image of the brain, fat appears _________ to white matter. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T1 weighted image of the brain, grey matter appears __________ to CSF. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T1 weighted image of the brain, white matter appears _______ to grey matter. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T1 weighted image of the knee, bone marrow appears _________ to meniscal tissues. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T2 weighted image of the brain, CSF appears _____________ to grey matter. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T2 weighted image of the brain, grey matter appears ___________ to white matter. A. hyperintense B. hypointense C. isointense
A. hyperintense
On a T2 weighted image of the spine, the intervertebral disk appears _____________ to the spinal cord. A. hyperintense B. hypointense C. isointense
A. hyperintense
The type of shimming that is achieved by placing a ferrous material around the main part of the magnet is known as ___________. A. passive shimming B. passive shielding C. active shimming D. active shielding
A. passive shimming
The time that both fat and water are in phase with each other is known as ____________. A. periodicity B. repetition time C. inversion time D. none of the above
A. periodicity
The horizontal axis of K space represents which axis of the image? A. phase encoding B. frequency encoding C. slice selection D. none of the above
A. phase encoding
Chemical misregistration artifact most commonly occurs in which direction of the MR image? A. phase encoding direction B. frequency encoding direction C. slice selection direction D. none of the above
A. phase encoding direction
Truncation artifact occurs in which direction of the MRI image? A. phase encoding direction B. frequency encoding direction C. slice selection direction D. none of the above
A. phase encoding direction
Foldover artifact caused by undersampling of signal in the phase encoding direction is known as _______. A. phase wrap B. frequency wrap C. Gibbs wrap D. none of the above
A. phase wrap
The speed at which protons rotate in an external magnetic field is known as ______________. A. precessional frequency B. hydromagnetic frequency C. external magnetic frequency D. none of the above
A. precessional frequency
The range of frequencies that is sampled during frequency encoding is known as the _________. A. receive bandwidth B. transmit bandwidth C. gradient slope D. none of the above
A. receive bandwidth
Which of the following methods can reduce blurring in a fast spin echo pulse sequence? A. reduce echo train length B. reduce resolution C. reduce TR D. reduce effect TE
A. reduce echo train length
In a gradient echo pulse sequence, transverse magnetization that is leftover from a previous excitation pulse is known as __________. A. residual transverse magnetization B. magnetization transfer C. chemical misregistration D. none of the above
A. residual transverse magnetization
Which of the following types of MRI magnet is known as the Classical electromagnet? A. resistive magnet B. superconducting magnet C. permanent magnet D. distractive magnet
A. resistive magnet
The RF pulse used to move nuclei into a higher energy state is at a frequency known as __________. A. resonance frequency B. fourier frequency C. transverse frequency D. none of the above
A. resonance frequency
In TOF MRA, which method is used to suppress signal from stationary tissue? A. saturation B. subtraction C. gradient moment nulling D. none of the above
A. saturation
Which method of image acquisition acquires all of the data from one slice before acquiring data from the next slice? A. sequential B. 2D volumetric C. 3D volumetric D. none of the above
A. sequential
In MRI, thick slices are achieved by applying a ________ gradient slope or a ______ bandwidth A. shallow, broad B. steep, narrow C. shallow, narrow D. none of the above
A. shallow, broad
Which of the following is the conventional technique used to produce a black appearance in vascular structures? A. short TE, short TR, pre-saturation pulse B. long TE, short TR, gradient moment nulling C. long TE, long TR, respiratory compensation D. none of the above
A. short TE, short TR, pre-saturation pulse
The gradient that is turned on during the application of the 90 degree excitation pulse and the 180 degree RF pulse is known as ________. A. slice selection gradient B. phase encoding gradient C. frequency encoding gradient D. none of the above
A. slice selection gradient
The ability to distinguish one structure from another on an image is known as _______. A. spatial resolution B. contrast to noise C. signal to noise D. none of the above
A. spatial resolution
The external magnetic field in a superconducting magnet is said to be what type of magnetic field? A. static B. kinetic C. gradient D. resistive
A. static
The type of RF configuration that is used to image anatomical structures close to the surface of the patient is known as __________. A. surface coil B. quadrature coil C. phased array coil D. shim coil
A. surface coil
In a gradient coil, the amplitude of the gradient slope is determined by what factor? A. the amount of current passing through the coil B. transmit bandwidth C. the strength of the external magnetic field D. none of the above
A. the amount of current passing through the coil
With the parameters given, which protocol gives the highest signal to noise ratio? A. thick slice/low TE/large FOV B. thin slice/high TE/small FOV C. thick slice/high TE/small FOV D. thin slice/low TE/small FOV
A. thick slice/low TE/large FOV
In figure 3-4, at a TR of 200, which of the following tissues has the greatest signal intensity? A. tissue A B. tissue B C. tissue C
A. tissue A
During a conventional spin echo pulse sequence, each slice is selected, phase encoded, and frequency encoded once per TR. A. true B. false
A. true
Each shim coil requires its own power supply. A. true B. false
A. true
The higher the number of excitations that are acquired the more K space that is filled. A. true B. false
A. true
The precessional frequency of hydrogen is influenced by its chemical environment. A. true B. false
A. true
The term "trade-off parameters" is used to describe parameters that affect each other inversely. A. true B. false
A. true
Longitudinal relaxation occurs more efficiently in which types of tissues? A. water B. fat C. muscle D. cortical bone
A. water
The effective clinical dosage of gadolinium is how many millimoles per kilogram of body weight? A. 1.0 mmol/kg B. 0.1 mmol/kg C. 10 mmol/kg D. 20 mmol/kg
B. 0.1 mmol/kg
In clinical MRI, superconducting magnets usually operate at field strengths from _________. A. 0.15 - 0.3 tesla B. 0.5 - 2 tesla C. 2.5 - 4 tesla D. over 4 tesla
B. 0.5 - 2 tesla
In clinical MRI, the homogeneity of the magnet should be at least __________. A. 1 tesla per cm B. 10 parts per million C. .5 gauss per meter D. 32 megahertz
B. 10 parts per million
Typical peak velocities of the distal aorta and iliac vessels are usually within what range? A. 150-175 cm/sec B. 100-160 cm/sec C. 80-120 cm/sec D. 40-70 cm/sec
B. 100-160 cm/sec
In conventional spin echo sequences, how many phase encoding steps must be selected to fill 128 lines of K space? A. 64 B. 128 C. 192 D. 256
B. 128
In a 1.0 tesla magnet, the difference in precessional frequency between fat and water is _________. A. 130 MHz B. 147 Hz C. 200 Hz D. 220 Hz
B. 147 Hz
At a field strength of 1.0 tesla, the approximate T2 relaxation time for blood is ___________. A. 140 ms B. 180 ms C. 240 ms D. 300 ms
B. 180 ms
The first MRI images of a human were obtained in what year? A. 1929 B. 1977 C. 1983 D. 1944
B. 1977
The first use of a paramagnetic agent on a human subject was in what year? A. 1976 B. 1981 C. 1946 D. 1973
B. 1981
At a field strength of 1.0 tesla, the approximate T1 relaxation time of liver tissue is ________. A. 180 ms B. 270 ms C. 360 ms D. 390 ms
B. 270 ms
Which method of image acquisition fills one line of k space for each slice in the sequence before it moves to the second line of k space? A. sequential B. 2D volumetric C. 3D volumetric D. none of the above
B. 2D volumetric
The recommended SAR limit for safely imaging the head is ___________. A. 0.4 watts/kg B. 3.2 watts/kg C. 8 watts/kg D. 4 watts/kg
B. 3.2 watts/kg
Which of the following PC MRA techniques provides the highest signal to noise ratio and spacial resolution? A. 2D PC MRA B. 3D PC MRA
B. 3D PC MRA
At 1.5 tesla, to reduce chemical misregistration artifact, the TE should be a multiple of what time? A. 3.1 ms B. 4.2 ms C. 6.6 ms D. 7.3 ms
B. 4.2 ms
Contrast agents presently used in MRI have what type of effect on tissue? A. Increase T2 relaxation times B. Decrease T1 relaxation times C. Increase T1 relaxation times D. None of the above
B. Decrease T1 relaxation times
As blood flow velocity decreases, the effects of time of flight phenomenon _____________. A. Increases B. Decreases C. Stays the same
B. Decreases
As slice thickness increases, the effects of time of flight phenomenon _____________
B. Decreases
As the echo time decreases, the effects of time of flight phenomenon _________________. A. Increases B. Decreases C. Stays the same
B. Decreases
The precessional frequency of hydrogen nuclei that experience decreased magnetic field strength due to gradient coils _______________. A. Increases B. Decreases C. Stays the same
B. Decreases
When TR is decreased, the effects of entry slice phenomenon _________. A. Increases B. Decreases C. Stays the same
B. Decreases
When slice thickness is increased, the effects of entry slice phenomenon ________. A. Increases B. Decreases C. Stays the same
B. Decreases
When the velocity of flow decreases, the effects of entry slice phenomenon ____________. A. Increases B. Decreases C. Stays the same
B. Decreases
Gd DTPA, also known as Magnevist, is bound by which chelate? A. Bismethylamide B. Diethylenetriamine pentaacetic acid C. Tertraazacyclododecane tetraacetic acid D. none of the above
B. Diethylenetriamine pentaacetic acid
Two types of cardiac gating that are most commonly used are known as _____________. A. respiratory gating, respiratory compensation B. ECG gating, peripheral gating C. pseudo gating, respiratory gating D. none of the above
B. ECG gating, peripheral gating
The first magnetic resonance experiments with solids were conducted by a group of scientists from Harvard University led by which of the following people? A. Felix Bloch B. Edward Purcell C. Otto Stern D. Paul Lauterbur
B. Edward Purcell
The flow phenomenon that is characterized by the contrast differences between fresh flowing nuclei entering a slice and stationary tissue within that slice is known as _________. A. Time of flight phenomenon B. Entry slice phenomenon C. Intra-voxel dephasing D. None of the above
B. Entry slice phenomenon
RF coils should be looped during scanning to improve signal to noise A. True B. False
B. False
The first oral MRI contrast agent used in a human subject was known as ________. A. Niobium-titanium B. Ferric chloride C. Ferric nitrate D. Gadopentetate dimeglumine
B. Ferric chloride
The center of the magnet where the magnetic field strength remains unchanged even during the application of gradient magnetic fields is known as the _____________. A. Pericenter B. Isocenter C. Monocenter D. None of the above
B. Isocenter
Blood flow that has consistent velocities within a vessel is known as what type of flow? A. Turbulent flow B. Laminar flow C. Vortex flow D. Stagnant flow
B. Laminar flow
The magnet's ability to attract and repel objects was first described by which of the following people? A. Alexander Necham B. Lucretius Cerus C. Hoang-ti D. None of the above
B. Lucretius Cerus
The area in Asia Minor that first discovered magnets is known as ________________. A. Rumania B. Magnesia C. Magnomia D. None of the above
B. Magnesia
The law of magnetic induction that is used in MRI today was developed by which of the following? A. Wilhelm Weber B. Michael Faraday C. Hans Christian D. Albert Einstein
B. Michael Faraday
Which of the following is a biological effect unique to echo planar imaging? A. Visual phosphenes B. Muscular twitches in face and back C. Tissue burns D. None of the above
B. Muscular twitches in face and back
For centuries, sailors used magnets for which of the following purposes? A. Lift heavy objects B. Navigate the seas C. Pull up anchors D. None of the above
B. Navigate the seas
MRI contrast agents known as T2 agents produce what type of contrast on T2 weighted images? A. Positive B. Negative
B. Negative
Which of the following people developed the most effective way to generate and transmit alternating current and has a magnetic unit of measurement named after him? A. Michael Faraday B. Nikola Tesla C. Niels Bohr D. Jean Baptiste Joseph Fourier
B. Nikola Tesla
The law that is used to determine the amount of resistance in a conductor is known as ___________. A. Newton's law B. Ohm's law C. Faraday's law D. Murphy's law
B. Ohm's law
Phase mismapping artifact always occurs in which direction of the MR image? A. Frequency direction B. Phase direction C. Slice selection direction D. Readout direction
B. Phase direction
Blood flow velocity at a given point is dependent upon which factor? A. Patient sex B. Phase of patients cardiac cycle C. Patients weight D. None of the above
B. Phase of patients cardiac cycle
The device in the MRI system that supplies power to the RF transmitter coils is known as the ______________. A. array processor B. RF amplifier C. gradient amplifier D. none of the above
B. RF amplifier
Which of the following people produced the first crude MRI image showing a rat tumor, which later appeared on the cover of Science magazine? A. Paul Lauterbur B. Raymond Damadian C. Felix Bloch D. Edward Purcell
B. Raymond Damadian
The effect of MRI contrast media on tissue relaxation rates is known as _________. A. Relaxation B. Relativity C. Realization D. None of the above
B. Relativity
The inversion recovery pulse sequence that is used to suppress fat in a T1 weighted image is known as ________. A. FLAIR B. STIR C. SSFP D. FLASH
B. STIR
The rate at which a patient can safely dissipate excess heat caused by RF energy is known as ____________. A. Specific absorption time B. Specific absorption rate C. Signal absorption rate D. None of the above
B. Specific absorption rate
Figure 3-2 displays which type of relaxation curve? A. T1 relaxation curve B. T2 relaxation curve C. inversion recovery curve
B. T2 relaxation curve
The time it takes for transverse magnetization to decay to 37% of its original value is known as ___________. A. T1 relaxation time B. T2 relaxation time C. T2* relaxation time
B. T2 relaxation time
MRI images that are based on the differences in the transverse relaxation characteristics of tissues are known as _____________. A. T1 weighted images B. T2 weighted images C. Proton density weighted images D. spin density weighted images
B. T2 weighted images
In an echo planar pulse sequence, using a long TE produces what type of weighting? A. T1 weighting B. T2 weighting C. proton density weighting D. none of the above
B. T2 weighting
In biological tissue, which type of relaxation occurs the quickest? A. T2 relaxation B. T2* relaxation C. T1 relaxation D. none of the above
B. T2* relaxation
Gradient echo pulse sequences that have coherent residual transverse magnetization produce what type of image weighting? A. T1 weighting B. T2* weighting C. proton density weighting D. both A and C
B. T2* weighting
The type of MRA that uses gradient echo pulse sequences and gradient moment nulling to enhance flow is known as _________________. A. digital subtraction B. TOF MRA C. PC MRA D. velocity encoding
B. TOF MRA
During cardiac gating, which of the following is the formula used to calculate available imaging time? A. F = y Bo B. Time = R-R interval - (trigger window + trigger delay) C. Time = R-R interval + (trigger window + trigger delay) D. none of the above
B. Time = R-R interval - (trigger window + trigger delay)
The word lodestone was derived from which of the following meanings? A. Attraction B. To find one's way C. Heavy D. None of the above
B. To find one's way
The Y gradient alters the magnetic field strength along which axis? A. Horizontal axis B. Vertical axis C. Long axis D. Short axis
B. Vertical axis
Blood flow velocity is greatest near which area of the vessel? A. Vessel walls B. Vessel center C. None of the above
B. Vessel center
During the acquisition of axial images of the body with the frequency direction L/R, phase encoding is performed by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
B. Y gradient
During the acquisition of axial images of the brain with the phase direction L/R, frequency encoding is performed by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
B. Y gradient
During the acquisition of sagittal images with the frequency direction S/I, phase encoding is conducted by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
B. Y gradient
Which of the following logical gradients is known as the phase encoding gradient? A. X gradient B. Y gradient C. Z gradient
B. Y gradient
A spin echo pulse sequence is characterized by which of the following? A. a 180 degree excitation pulse followed by a 90 degree rephasing pulse B. a 90 degree excitation pulse followed by a 180 degree rephasing pulse C. a 90 degree excitation pulse followed by a 90 degree rephasing pulse D. none of the above
B. a 90 degree excitation pulse followed by a 180 degree rephasing pulse
The artifact that is produced when anatomy that is outside the FOV is mapped within the FOV is known as __________. A. phase mismapping B. aliasing C. partial volume averaging D. magnetic susceptibility
B. aliasing
Image data with low spatial resolution is stored in which area of k space? A. outer lines B. central lines C. negative lines only D. positive lines only
B. central lines
The artifact that is caused due to the difference in precessional frequencies between fat and water is called __________. A. magnetic susceptibility B. chemical shift C. truncation D. aliasing
B. chemical shift
Gradient echo pulse sequences that preserve left over transverse magnetization are said to be ________. A. incoherent B. coherent C. consistent D. inconsistent
B. coherent
When the direction of blood flow is the same as the direction in which slices are acquired, the effects of entry slice phenomenon __________. A. increase B. decrease C. stay the same
B. decrease
As bandwidth increases, sampling time _____________. A. increases B. decreases C. stays the same
B. decreases
When bandwidth is increased, signal to noise ratio _______. A. increases B. decreases C. stays the same
B. decreases
When echo time is increased, signal to noise ratio ________. A. increases B. decreases C. stays the same
B. decreases
When image matrix is decreased, spacial resolution _______. A. increases B. decreases C. stays the same
B. decreases
When the number of excitations is decreased, acquisition time __________. A. increases B. decreases C. stays the same
B. decreases
When voxel size decreases, signal to noise ratio ________. A. increases B. decreases C. stays the same
B. decreases
Volume averaging artifact can be reduced by which of the following methods? A. increasing slice thickness B. decreasing slice thickness C. increasing NEX D. decreasing NEX
B. decreasing slice thickness
The device used to store and transport cryogenic liquids is known as a _________. A. thermos B. dewar C. barrel D. none of the above
B. dewar
The type of neoplasms in the head that enhance primarily due to their increase in vascularity are known as _________. A. intra axial neoplasms B. extra axial neoplasms C. metastatic neoplasms D. none of the above
B. extra axial neoplasms
Neoplasms outside the spinal cord but within the CSF space are said to be located in which of the following locations? A. intramedullary B. extramedullary intradural C. extradural D. none of the above
B. extramedullary intradural
The letters FID in and FID signal stand for __________. A. field image dimensions B. free induction decay C. field induction direction D. free image direction
B. free induction decay
The vertical axis of K space represents which axis of the image? A. phase encoding B. frequency encoding C. slice selection D. none of the above
B. frequency encoding
Chemical shift artifact occurs in which direction of the MR image? A. phase encoding direction B. frequency encoding direction C. slice selection direction D. none of the above
B. frequency encoding direction
Wraparound artifact caused by undersampling of frequencies in the readout direction is known as __________. A. phase wrap B. frequency wrap C. Gibbs wrap D. truncation
B. frequency wrap
The type of signal that is created after a gradient is used to refocus the dephasing net vector is known as __________. A. spin echo signal B. gradient echo signal C. FID signal D. none of the above
B. gradient echo signal
Bright pixels on an MRI image represent what type of signal? A. low B. high C. weak D. none of the above
B. high
The stronger the magnetic field the ____________ the precessional frequency A. stronger B. higher C. longer D. shorter
B. higher
In a T2 weighted image, tissues with short T2 relaxation times appear __________. A. hyperintense B. hypointense C. isointense D. none of the above
B. hypointense
In a proton density weighted image, tissues with a low number of hydrogen nuclei appear ___________. A. hyperintense B. hypointense C. isointense D. none of the above
B. hypointense
On a T1 weighted image of the brain, CSF appears ____________ to fat. A. hyperintense B. hypointense C. isointense
B. hypointense
On a T1 weighted image of the knee, cortical bone appears ____________ to all other tissues. A. hyperintense B. hypointense C. isointense
B. hypointense
On a T1 weighted image of the spine, the intervertebral disk appears __________ to spinal cord. A. hyperintense B. hypointense C. isointense
B. hypointense
On a proton density weighted image of the brain, CSF appears _________ to grey matter. A. hyperintense B. hypointense C. isointense
B. hypointense
On a proton density weighted image of the brain, white matter appears __________ to grey matter. A. hyperintense B. hypointense C. isointense
B. hypointense
The difference in brightness between two regions of an image is known as __________. A. signal to noise B. image contrast C. spacial resolution D. none of the above
B. image contrast
The technique used to eliminate cross excitation artifact that acquired data in two separate acquisitions from alternating slices is known as _________. A. aliasing B. interleaving C. spin warping D. none of the above
B. interleaving
Three types of ferromagnetic material are ____________________. A. copper, titanium, aluminum B. iron, cobalt, nickel C. bronze, niobium, tin D. none of the above
B. iron, cobalt, nickel
A volume element that has the same height, width, and depth is known as _____________. A. rectangular B. isotropic C. triangular D. anisotropic
B. isotropic
Gadodiamide, also known as Omniscan, is based on what type of molecular structure? A. linear ionic B. linear nonionic C. macrocyclic ionic D. macrocyclic nonionic
B. linear nonionic
In a T1 weighted image, CSF has a ________________ T1 relaxation time and therefore appears _____________. A. long, bright B. long, dark C. short, dark D. short, bright
B. long, dark
Another name for T1 relaxation is ___________. A. dephasing B. longitudinal relaxation C. spin-spin relaxation D. transverse relaxation
B. longitudinal relaxation
In a T1 weighted image, tissues with long T1 relaxation times produce what type of signal? A. high B. low C. intermediate D. none of the above
B. low
When the phase encoding gradient is activated, steep slopes produce what type of signal amplitude? A. high B. low C. medium D. none of the above
B. low
Which of the following is an advantage of using a resistive magnet for clinical MRI? A. high power consumption B. low capital cost C. low field strength D. none of the above
B. low capital cost
Which of the following is an advantage of a permanent magnet MRI system? A. very heavy B. low operating cost C. fixed field strength
B. low operating costs
Which of the following is an advantage of a permanent magnet MRI system? A. very heavy B. low operating costs C. fixed field strength D. limited field strength
B. low operating costs
An image with a grainy appearance usually represents an image with _____. A. high resolution B. low signal to noise C. high signal to noise D. low resolution
B. low signal to noise
Because the nucleus of the hydrogen atom acts much like a bar magnet it is said to have a _________. A. magnetic ratio B. magnetic moment C. larmor ratio D. frequency ratio
B. magnetic moment
The vascular imaging method that maximizes vascular contrast while also suppressing stationary tissue is known as ___________. A. magnetic resonance mammography B. magnetic resonance angiography C. black blood imaging D. zeugmatography
B. magnetic resonance angiography
The process of filling only a percentage of k space with acquired data and filling the rest with zeros is known as _________. A. partial saturation B. partial averaging C. partial voluming D. partial echo
B. partial averaging
The method of MRI field containment that uses steel lining in the walls of the magnetic room is known as ___. A. active shimming B. passive shielding C. active shielding D. passive shimming
B. passive shielding
TOF MRA is most sensitive to blood flow that flows in what direction in relation to the slice? A. parallel B. perpendicular
B. perpendicular
The spacial location of signal according to its precessional phase is known as __________. A. slice selection B. phase encoding C. frequency encoding D. readout
B. phase encoding
The gradient that is turned on just before the 180 degree rephasing pulse is known as the ________. A. slice selection gradient B. phase encoding gradient C. frequency encoding gradient D. none of the above
B. phase encoding gradient
Figure 6-3 displays an example of what type of artifact? A. ringing B. phase wrap C. chemical shift D. cross talk
B. phase wrap
The type of RF coil configuration that uses a series of independent coils to create one image is known as ___________. A. surface coil B. phased array coil C. quadrature coil D. gradient coil
B. phased array coil
The term used to describe a picture element is known as a ____________. A. image element B. pixel C. voxel D. volume element
B. pixel
The effects of time of flight and entry slice phenomena can be minimized by which method? A. gradient moment nulling B. pre-saturation RF pulse C. respiratory compensation D. none of the above
B. pre-saturation RF pulse
The positively charged component of an atom is called the ___________. A. electron B. proton C. positron D. neutron
B. proton
Noise that generally degrades overall quality of an MRI image is known as ___________. A. inherent noise interference B. random noise interference C. discrete noise interference D. none of the above
B. random noise interference
During the sampling of signal, the sampling rate is directly proportional to the __________. A. sampling time B. receive bandwidth C. transmit bandwidth D. none of the above.
B. receive bandwidth
The time between two successive 90 degree RF pulses is known as ___________. A. echo time B. repetition time C. inversion time D. relaxation time
B. repetition time
Three characteristics commonly used to define the quality of an MRI image are ________. A. contrast, resolution, matrix B. resolution, contrast, signal to noise C. signal to noise, excitations, contrast D. resolution, matrix, signal to noise
B. resolution, contrast, signal to noise
The rule that is used to determine the direction of the magnetic field in an electromagnet is known as _______. A. Ohm's law B. right hand thumb rule C. left hand thumb rule D. none of the above
B. right hand thumb rule
The method used to contain the main magnetic field within the scan room is known as ________. A. shimming B. shielding C. fringing D. none of the above
B. shielding
The proportion of signal actually used to construct an image relative to the amount of background noise is known as __________. A. spacial resolution B. signal to noise ratio C. image contrast D. none of the above
B. signal to noise ratio
The magnitude of the phase shifts between two points within a patient is determined by which factor? A. slope of the frequency encoding gradient B. slope of the phase encoding gradient C. strength of the RF pulse D. none of the above
B. slope of the phase encoding gradient
Figure 5-2 is a diagram showing what type of pulse sequence? A. partial saturation B. spin echo C. inversion recovery D. gradient echo
B. spin echo
The signal produced after the 180 degree RF pulse is applied is known as a _______________. A. gradient echo signal B. spin echo signal C. spin spin signal D. FID signal
B. spin echo signal
In a gradient echo pulse sequence, the process of eliminating residual transverse magnetization is known as ___________. A. warping B. spoiling C. rewinding D. none of the above
B. spoiling
The condition that occurs in a gradient echo pulse sequence when the TR is short than the T1 and T2 relaxation times of tissue is known as __________. A. chemical shift B. steady state C. frequency shift D. phase shift
B. steady state
The gradient echo pulse sequence that is characterized by an echo time that is longer than its repetition time is known as __________. A. echo planar B. steady state free precession C. spin echo D. fast spin echo
B. steady state free precession
In MRI, thin slices are achieved by applying a ________ gradient slope or a __________ bandwidth. A. shallow, broad B. steep, narrow C. shallow, narrow D. none of the above
B. steep, narrow
The larger the net magnetic vector in the transverse plane the __________ the signal that is produced. A. smaller B. stronger C. weaker D. none of the above
B. stronger
The type of MRI magnet that allows the highest field strengths is a __________. A. resistive magnet B. superconducting magnet C. iron core magnet D. permanent magnet
B. superconducting magnet
Within a perfect magnetic field all protons rotate at __________. A. different frequencies B. the same frequency C. Undetermined frequencies D. none of the above
B. the same frequency
In figure 3-5, at a TE of 90, which of the following tissues has the greatest signal intensity? A. tissue A B. tissue B C. tissue C
B. tissue B
The range of frequencies that is transmitted by the RF pulse is known as the ___________. A. receive bandwidth B. transmit bandwidth C. gradient slope D. none of the above
B. transmit bandwidth
The amount of a drug required to cause death in half of a sample of lab mice is known as ______. A. LD50 B. LR50 C. Median lethal dose D. Both A and C
Both A and C
The magnetic field that surrounds the Earth has what field strength? A. 0.5 Tesla B. 0.6 Tesla C. 0.5 gauss D. 1.5 tesla
C. 0.5 gauss
10,000 gauss is equal to ________. A. 1.0 amp B. 1.0 ohm C. 1.0 tesla D. 10 tesla
C. 1.0 Tesla
15,000 gauss is equal to _____________. A. 1.5 amps B. 1.5 ohms C. 1.5 tesla D. 15 tesla
C. 1.5 tesla
At a field strength of 1.0 tesla, the approximate T2 relaxation time for renal medulla tissue is ________. A. 90 ms B. 100 ms C. 140 ms D. 300 ms
C. 140 ms
At a field strength of 1.0 tesla, the approximate T1 relaxation time for CSF is ______. A. 800 ms B. 1000 ms C. 2000 ms D. 2500 ms
C. 2000 ms
How many gradient coils are there in a clinical MRI system? A. 1 pair B. 2 pairs C. 3 pairs D. 4 pairs
C. 3 pairs
There are how many pairs of gradient coils in a standard MRI system? A. 1 pair B. 2 pairs C. 3 pairs D. 4 pairs
C. 3 pairs
To decrease the chances of cross excitation there should be at least what percentage of interslice gap? A. 10% B. 15% C. 30% D. 50%
C. 30%
Typical peak velocities of the vertebral and basilar arteries are usually within what range? A. 80-120 cm/sec B. 50-70 cm/sec C. 30-50 cm/sec D. Under 20 cm/sec
C. 30-50 cm/sec
At a field strength of 1.0 tesla, the approximate T1 relaxation time for renal cortex tissue is ________. A. 180 ms B. 270 ms C. 360 ms D. 390 ms
C. 360 ms
Which method of image acquisition acquires data from an entire volume of tissue, then uses a method called slice encoding to separate the images? A. sequential B. 2D volumetric C. 3D volumetric
C. 3D volumetric
Typical peak velocities of the middle and anterior cerebral arteries are usually within what range? A. 150-175 cm/sec B. 100-150 cm/sec C. 40-70 cm/sec D. 30-50 cm/sec
C. 40-70 cm/sec
At a field strength of 1.0 tesla, the approximate T1 relaxation time for grey matter is ____________. A. 390 ms B. 450 ms C. 520 ms D. 620 ms
C. 520 ms
At a field strength of 1.0 tesla, the approximate T1 relaxation time for muscle tissue is ____________________. A. 270 ms B. 480 ms C. 600 ms D. 680 ms
C. 600 ms
At a field strength of 1.0 tesla, the approximate T1 relaxation time for renal medulla tissue is ________. A. 520 ms B. 600 ms C. 680 ms D. 800 ms
C. 680 ms
The recommended SAR limit for safely imaging small volumes is _________. A. 0.4 watts/kg B. 3.2 watts/kg C. 8 watts/kg D. 4 watts/kg
C. 8 watts/kg
Typical peak velocities of the proximal carotid, brachial and superficial femoral arteries are usually within what range? A. 150-175 cm/sec B. 100-160 cm/sec C. 80-120 cm/sec D. 40-70 cm/sec
C. 80-120 cm/sec
At a field strength of 1.0 tesla, the approximate T1 relaxation time for blood is __________. A. 540 ms B. 680 ms C. 800 ms D. 1000 ms
C. 800 ms
Ghosting artifact on an MR image caused by the heart can be decreased by which of the following methods? A. Decreasing bandwidth B. Peripheral compensation C. Cardiac gating D. Respiratory compensation
C. Cardiac gating
MRI contrast agents known as T2 agents have what type of effect on tissue? A. Increase T2 relaxation times B. Increase T1 relaxation times C. Decrease T2 relaxation times D. None of the above
C. Decrease T2 relaxation times
The first material used by Felix Bloch to change magnetic relaxation times was known as __________. A. Niobium-titanium B. Gadopentetate dimeglumine C. Ferric nitrate D. Nickel-cadmium
C. Ferric nitrate
Motion artifact on an MR image caused by flowing blood or CSF can be decreased by which of the following methods? A. Respiratory compensation B. Patient education C. Gradient moment nulling D. Respiratory gating
C. Gradient moment nulling
The first whole body MRI scanner used by Dr. Raymond Damadian was known as the ______________. A. Signa B. Gyroscan C. Indomitable D. Abominable
C. Indomitable
The Z gradient alters the magnetic field strength along which axis? A. Horizontal axis B. Vertical axis C. Long axis D. Short axis
C. Long axis
The first magnets were called Magnetites because the people that lived in the area where they were found were known as ________. A. Magnesians B. Magnomians C. Magnetes D. None of the above
C. Magnetes
Which of the following people received the 1922 Nobel prize in physics for his theory of the atomic structure? A. Michael Faraday B. Nikola Tesla C. Niels Bohr D. Otto Stern
C. Niels Bohr
Blood flow that receives a 180 degree rephasing pulse but not a 90 degree excitation pulse produces what type of signal? A. High signal B. Low signal C. No signal
C. No signal
Blood flow that receives a 90 degree excitation pulse but not a 180 degree rephasing pulse produces what type of signal? A. High signal B. Low signal C. No signal
C. No signal
Which of following people received the 1943 Nobel prize in physics for his development of a method to study the magnetic moments of atoms by directing atomic beams through magnetic fields? A. Nikola Tesla B. Thomas Edison C. Otto Stern D. Niels Bohr
C. Otto Stern
The type of MRA that produces image contrast based on the differences in phase shifts between blood flow and stationary tissue is known as _________. A. TOF MRA B. Velocity encoding C. PC MRA D. None of the above
C. PC MRA
Which of the following patients should be absolutely excluded from having an MRI exam? A. Patients with hip replacements B. Patients with titanium aneurysm clips C. Patients with cardiac pacemakers D. Patients with cornea implants
C. Patients with cardiac pacemakers
Which of the following people named the ends of a magnet north and south poles? A. Louis Faraday B. Alexander Necham C. Petrus Peregtinus de Maricourt D. Hans Christian
C. Petrus Peregtinus de Maricourt
During cardiac gating, which wave is used to trigger each pulse sequence? A. P wave B. Q wave C. R wave D. T wave
C. R wave
During cardiac gating, the time between two consecutive R waves is known as _________. A. trigger window B. trigger delay C. R-R interval D. none of the above
C. R-R interval
During slice selection, the X gradient is used to select slices in which plane? A. Coronal B. Axial C. Sagittal D. None of the above
C. Sagittal
The 3 primary functions that gradients perform during MR scanning are ___________. A. Slice selection, RF application, frequency encoding B. Phase encoding, frequency encoding, RF application C. Slice selection, phase encoding, frequency encoding D. None of the above
C. Slice selection, phase encoding, frequency encoding
A spin echo image with a long TR and a long TE is known as what type of image? A. T1 weighted image B. proton density weighted image C. T2 weighted image D. spin density weighted image
C. T2 weighted image
Which imaging parameter affects the amount of chemical misregistration that will be seen on an image? A. TR B. TI C. TE D. NEX
C. TE
Gd DOTA, also known as Dotarem, is bound by what chelate? A. Bismethylamide B. Diethylenetriamine pentaacetic acid C. Tertraazacyclododecane tetraacetic acid D. none of the above
C. Tertraazacyclododecane tetraacetic acid
Blood flow that has high velocities in the center of the vessel but spirals near walls of the vessel due to a stricture is known as what type of flow? A. Turbulent flow B. Laminar flow C. Vortex flow D. Stagnant flow
C. Vortex flow
During the acquisition of coronal images with the phase direction L/R, frequency encoding is conducted by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
C. Z gradient
During the acquisition of sagittal images with the phase direction, A/P, frequency encoding is performed by which physical gradient? A. X gradient B. Y gradient C. Z gradient D. None of the above
C. Z gradient
Which of the following logical gradients is known as the slice selection gradient? A. X gradient B. Y gradient C. Z gradient
C. Z gradient
Scientist Paul Lauterbur described an NMR imaging technique called _____________. A. Magnetography B. Positron Tomography C. Zeugmatography D. Computed Tomography
C. Zeugmatography
The method of MRI field containment that uses additional magnets outside the cryogenic area of the magnet is known as _________. A. active shimming B. passive shielding C. active shielding D. passive shimming
C. active shielding
The type of shimming that is achieved by adjusting the electrical current in specialized coils is known as __________. A. passive shimming B. passive shielding C. active shimming D. active shielding
C. active shimming
Which of the following materials is most commonly used to produce a permanent magnet? A. niobium-titanium alloy B. copper-gadolinium alloy C. aluminum-nickel-colbalt alloy D. iron
C. aluminum-nickel-colbalt alloy
After being placed in an external magnetic field, high energy hydrogen nuclei point in which direction? A. parallel B. anti-paired C. anti-parallel D. perpendicular
C. anti-parallel
Which of the following is an example of an intra axial neoplasm? A. acoustic neuroma B. meningioma C. astrocytoma D. both A and B
C. astrocytoma
When placed in an external magnetic field, hydrogen nuclei ______________. A. resonate B. become excited C. become aligned D. repel each other
C. become aligned
The method that is most commonly used to reduce artifact produced by cardiac motion when scanning the chest is known as _________. A. respiratory gating B. respiratory compensation C. cardiac gating D. none of the above
C. cardiac gating
The artifact that is caused by the phase differences between fat and water is known as ___________. A. chemical shift B. phase wrap C. chemical misregistration D. ringing
C. chemical misregistration
Figure 6-4 displays an example of what type of artifact? A. phase mismapping B. aliasing C. chemical shift D. cross excitation
C. chemical shift
Blood flow velocity is measured in what type of unit? A. Gauss/sec B. mm/sec C. cm/sec D. Inches/sec
C. cm/sec
Mutual induction between the RF transmitter and the RF receiver is known as __________. A. isolation B. deisolation C. coupling D. decoupling
C. coupling
The artifact produced by the transfer of spin lattice energy from one slice to its adjacent slice is known as ____________. A. wraparound artifact B. ringing artifact C. cross talk artifact D. magnetic susceptibility
C. cross talk artifact
The liquids used to cool the wire in the main magnetic field of a superconducting magnet are known as __________. A. neon gases B. plasma C. cryogens D. none of the above
C. cryogens
An artifact caused by faulty receiver attenuation settings during prescan is known as ____________. A. herringbone B. shading C. data clipping D. aliasing
C. data clipping
Because the spinning nucleus of the hydrogen atom has both a North and South pole it is commonly called a __________. A. electromagnet B. bar magnet C. dipole
C. dipole
Noise that degrades image quality in a specific location within an MRI image is known as __________. A. inherent noise interference B. random noise interference C. discrete noise interference D. none of the above
C. discrete noise interference
The type of pulse sequence that fills all lines of k space per TR is known as _____________. A. fast spin echo B. steady state free precession C. echo planar D. spin echo
C. echo planar
In a RARE pulse sequence, the multiple number of echo times that create image weighting are averaged together to produce what is known as the __________. A. effective TR B. effective TI C. effective TE D. none of the above
C. effective TE
In 1825, the British scientist, William Surgeon, constructed the first ______________. A. Superconducting magnet B. Permanent magnet C. Electromagnet D. None of the above
C. electromagnet
The method of acquiring more than one echo that are multiples of each other to reduce intra-voxel dephasing is known as _____________. A. gradient moment nulling B. pre-saturation RF pulse C. even echo rephasing D. none of the above
C. even echo rephasing
Neoplasms of the spine that are outside the spinal cord and outside the CSF space are said to be located in which of the following locations? A. intramedullary B. extramedullary intradural C. extradural D. none of the above
C. extradural
The pulse sequence that performs a series of 180 degree rephasing pulses and echos is known as ____. A. echo planar B. inversion recovery C. fast spin echo D. conventional spin echo
C. fast spin echo
Material that is strongly attracted to a magnetic field is said to be __________. A. electromagnetic B. paramagnetic C. ferromagnetic D. diamagnetic
C. ferromagnetic
When a patient is placed in an external magnetic field, the number of unmatched hydrogen protons usually equals _________. A. one billion B. one million C. few per million D. few per billion
C. few per million
In a gradient echo pulse sequence, which parameter directly affects image weighting? A. NEX B. field of view C. flip angle D. matrix
C. flip angle
The strength of a magnet is measured by its __________. A. signal intensity B. induction ability C. flux density D. none of the above
C. flux density
The spacial location of signal according to its precessional frequency is known as __________. A. slice selection B. phase encoding C. frequency encoding D. spoiling
C. frequency encoding
In a gradient echo pulse sequence, which gradient is used to dephase and rephase nuclei? A. slice select gradient B. phase encoding gradient C. frequency encoding gradient D. none of the above
C. frequency encoding gradient
The gradient that is turned on during signal sampling is known as the ____________. A. slice selection gradient B. phase encoding gradient C. frequency encoding gradient D. none of the above
C. frequency encoding gradient
In an MRI system, the magnetic field that extends outside the bore of the magnet is known as _________. A. extended field B. outer field C. fringe field D. in field
C. fringe field
The device in the MRI system that supplies power to the gradient coils is known as the __________. A. array processor B. RF amplifier C. gradient amplifier D. none of the above
C. gradient amplifier
Magnetic susceptibility artifact is most prominent in what type of pulse sequence? A. spin echo B. inversion recovery C. gradient echo D. none of the above
C. gradient echo
Chemical misregistration artifact is most likely to affect which type of pulse sequence? A. spin echo pulse sequences B. inversion recovery pulse sequences C. gradient echo pulse sequences D. none of the above
C. gradient echo pulse sequences
Cross excitation artifact is less likely to occur with which pulse sequence? A. spin echo, 90 degree flip angle, 10% interslice gap B. spin echo, 90 degree flip angle, 50% interslice gap C. gradient echo, 15 degree flip angle, 30% interslice gap D. dual echo, 90 degree flip angle, 25% interslice gap
C. gradient echo, 15 degree flip angle, 30% interslice gap
Which of the following is the conventional technique used to produce a bright appearance in vascular structures? A. pre-saturation pulse B. respiratory compensation C. gradient moment nulling D. none of the above
C. gradient moment nulling
In a gradient echo pulse sequence, the use of a gradient to eliminate residual transverse magnetization is known as ______________. A. digital RF spoiling B. frequency spoiling C. gradient spoiling D. none of the above
C. gradient spoiling
Which of the following is a disadvantage of a resistive magnet MRI system? A. easy coil maintenance B. low cost C. high power consumption D. none of the above
C. high power consumption
Dephasing of the net vector in the transverse plane is caused by two factors, imperfections in the external magnetic field and ________________. A. the application of the 180 degree RF pulse B. the application of a 90 degree RF pulse C. interaction between surrounding nuclei D. none of the above
C. interaction between surrounding nuclei
The flow phenomenon that is characterized by phase differences between flowing and stationary nuclei within a voxel is known as ________. A. time of flight phenomenon B. entry slice phenomenon C. intra-voxel dephasing D. none of the above
C. intra-voxel dephasing
Figure 5-3 is a diagram showing what type of pulse sequence? A. partial saturation B. spin echo C. inversion recovery D. gradient echo
C. inversion recovery
The type of spin echo pulse sequence that begins with a 180 degree inversion RF pulse and is followed by a 90 degree excitation pulse is known as ________. A. echo planar B. gradient echo C. inversion recovery D. gradient reversal
C. inversion recovery
Figure 3-3 displays which type of relaxation curve? A. T1 relaxation curve B. T2 relaxation curve C. inversion recovery curve
C. inversion recovery curve
During an inversion recovery pulse sequence, the time between the 180 degree inversion pulse and the 90 degree excitation pulse is known as ___________. A. echo time B. repetition time C. inversion time D. reversion time
C. inversion time
In an inversion recovery pulse sequence, the time between the 180 degree RF pulse and the 90 degree RF pulse is known as __________. A. echo time B. repetition time C. inversion time D. relaxation time
C. inversion time
Contrast agents that separate into charged ions in water are said to be ___________. A. hydrophilic B. nonionic C. ionic D. none of the above
C. ionic
Which of the following is a disadvantage of using a permanent magnet in clinical MRI? A. low fringe field B. low operating costs C. low field strength D. both A and B
C. low field strength
Gadoterate meglumine, also known as Dotarem, is based on what type of molecular structure? A. linear ionic B. linear nonionic C. macrocyclic ionic D. macrocyclic nonionic
C. macrocyclic ionic
In a T1 weighted image, a short TR is used to _____________. A. maximize T2 effects B. minimize T2 effects C. maximize T1 effects D. minimize T1 effects
C. maximize T1 effects
When the phase encoding gradient is activated, medium slopes produce what type of signal amplitudes? A. high B. low C. medium D. none of the above
C. medium
The neutral component of an atom is called the _______. A. electron B. proton C. neutron D. photon
C. neutron
The diffusion of fluid thorough a semipermeable membrane such as the wall of a living cell is known as _________. A. hydrosis B. ionization C. osmosis D. none of the above
C. osmosis
When placed in an external magnetic field, the hydrogen nuclei that are of clinical interest are ______________. A. parallel paired B. anti-parallel paired C. parallel unpaired D. perpendicular paired
C. parallel unpaired
The artifact that is produced when many structures with different signal intensities are averaged together within a pixel is known as _________. A. cross talk artifact B. truncation artifact C. partial volume averaging D. aliasing artifact
C. partial volume averaging
The type of cardiac gating that detects the increase in blood volume in the capillary bed during systole is known as _________. A. ECG gating B. pseudo gating C. peripheral gating D. none of the above
C. peripheral gating
Which of the following type of MRA uses bipolar gradient to enhance vascular structures? A. TOF MRA B. bright blood imaging C. phase contrast MRA D. black blood imaging
C. phase contrast MRA
The nucleus of the hydrogen atom carries what type of charge? A. negative B. neutral C. positive
C. positive
The type of rotation that is displayed by hydrogen nuclei in an external magnetic field is known as ___________. A. magnetization B. relaxation C. precession D. resonance
C. precession
MRI images that are based on the differences in the amount of hydrogen nuclei in tissues are known as _________. A. T1 weighted images B. T2 weighted images C. Proton density weighted images D. transitional images
C. proton density weighted images
The type of RF coil configuration that uses a pair of coils perpendicular to each other to transmit and receive signal is known as ___________. A. surface coil B. phased array coil C. quadrature coil D. shim coil
C. quadrature coil
The frequency encoding gradient is also known as the ___________ because it is turned on during the sampling of signal. A. refocusing gradient B. spoiler gradient C. readout gradient D. phase encoding gradient
C. readout gradient
The process during the prescan that determines the amount of signal that is received is known as ________. A. center frequency adjustment B. transmit gain adjustment C. receive attenuation adjustment D. impedance matching
C. receive attenuation adjustment
The image parameter that primarily affects T1 weighting is ______________. A. echo time B. inversion time C. repetition time D. none of the above
C. repetition time
In a gradient echo pulse sequence, the process of reversing the slope of the phase encoding gradient after readout to preserve residual transverse magnetization is known as _________. A. warping B. spoiling C. rewinding D. none of the above
C. rewinding
The time it takes for a gradient coil to reach its peak strength is known as its __________. A. repetition time B. echo time C. rise time D. inversion time
C. rise time
The rate at which signal samples are taken during frequency encoding is known as the ___________. A. readout rate B. frequency rate C. sampling rate D. none of the above
C. sampling rate
The artifact that is characterized by a loss of signal intensity in one area of an image is known as __________. A. aliasing artifact B. ringing artifact C. shading artifact D. none of the above
C. shading artifact
In a T2 weighted image, fat has a ___________ T2 relaxation time and therefore appears ______________. A. long, bright B. long, dark C. short, dark D. short, bright
C. short, dark
Gradient moment nulling is most effective on which type of flow? A. slow turbulent flow B. fast laminar flow C. slow laminar flow D. fast vortex flow
C. slow laminar flow
The clarity with which different areas of an image are distinguished is known as _______. A. image contrast B. signal to noise C. spacial resolution D. none of the above
C. spacial resolution
Which of the following is the pulse sequence that is used most commonly? A. inversion recovery B. gradient echo C. spin echo D. echo planar
C. spin echo
Another name for transverse relaxation is __________. A. spin-lattice relaxation B. T1 relaxation C. spin-spin relaxation D. longitudinal relaxation
C. spin-spin relaxation
When TE is decreased, the spacial resolution ________. A. increases B. decreases C. stays the same
C. stays the same
When the number of excitations is increased, spacial resolution ________. A. increases B. decreases C. stays the same
C. stays the same
The strength of an MRI magnet is most commonly represented by a unit of measurement called __________. A. amps B. kilogauss C. tesla D. ohms
C. tesla
Hydrogen nuclei begin to precess in phase when which of the following occurs? A. the proper RF is turned off B. the patient is placed into the external magnet C. the proper RF is turned on D. none of the above
C. the proper RF is turned on
Magnetization in the XY plane is known as ___________. A. equilibrium B. longitudinal magnetization C. transverse magnetization D. spin-lattice magnetization
C. transverse magnetization
During cardiac gating, the waiting time between the R wave and the start of the data acquisition is known as ____________. A. repetition time B. inversion time C. trigger delay D. echo delay
C. trigger delay
The T wave of the ECG represents which phase of the cardiac cycle? A. atrial systole B. ventricular systole C. ventricular diastole D. atrial diastole
C. ventricular diastole
The type of RF coil that encompasses the entire anatomy to be scanned is known as ____________. A. surface coil B. phased array coil C. volume coil D. gradient coil
C. volume coil
The term used to describe a volume element is known as _________. A. pixel B. pixie C. voxel D. picture element
C. voxel
What type of molecule makes up 50% to 90% of a person's total body weight? A. fat B. oxygen C. water D. nitrogen
C. water
The smaller the net magnetic vector in the transverse plane the ___________ the signal that is produced. A. larger B. stronger C. weaker D. none of the above
C. weaker
Heating that is directly associated with the RF pulse sequence should not increase the core body temp greater than ________. A. 1 degree Fahrenheit B. 1 degree kelvin C. 10 degree Celsius D. 1 degree Celsius
D. 1 degree Celsius
Which of the following is the median lethal dose of Gadopentetate dimeglumine? A. 0.5 mmol/kg B. 5 mmol/kg C. 1 mmol/kg D. 10-20 mmol/kg
D. 10-20 mmol/kg
At a field strength of 1.0 tesla, the approximate T2 relaxation time for grey matter is _________. A. 70 ms B. 80 ms C. 90 ms D. 100 ms
D. 100 ms
Dr. Raymond Damadian was inducted into the National Inventors Hall of Fame for his invention of the first human scanner in what year? A. 1974 B. 1978 C. 1982 D. 1989
D. 1989
The precessional frequency of hydrogen at .5 Tesla is ______________. A. 42.6 MHz B. 63.86 MHz C. 25.48 MHz D. 21.28 MHz
D. 21.28 MHz
In a 1.5 tesla magnet, the difference in precessional frequency between fat and water is __________. A. 250 MHz B. 210 MHz C. 220 watts D. 220 Hz
D. 220 Hz
At a field strength of 1.0 tesla, the approximate T1 relaxation time for water is ___________. A. 800 ms B. 1000 ms C. 2000 ms D. 2500 ms
D. 2500 ms
At a field strength of 1.0 tesla, the approximate T2 relaxation time for water is _________. A. 800 ms B. 1000 ms C. 2000 ms D. 2500 ms
D. 2500 ms
In conventional spin echo sequences, how many phase encoding steps must be selected to fill 256 lines of K space? A. 64 B. 128 C. 192 D. 256
D. 256
At a field strength of 1.0 tesla, the approximate T2 relaxation time for CSF is __________. A. 70 ms B. 100 ms C. 180 ms D. 300 ms
D. 300 ms
At a field strength of 1.0 tesla, the approximate T1 relaxation time for white matter is ________. A. 180 ms B. 270 ms C. 360 ms D. 390 ms
D. 390 ms
At a field strength of 1.0 tesla, the approximate T1 relaxation time for spleen tissue is ________. A. 360 ms B. 380 ms C. 400 ms D. 480 ms
D. 480 ms
How many miliseconds are there in a minute? A. 60 B. 600 C. 6,000 D. 60,000
D. 60,000
At .5 tesla, to reduce chemical misregistration artifact, the TE should be a multiple of what time? A. 3.1 ms B. 4.2 ms C. 6.6 ms D. 7.0 ms
D. 7.0 ms
At a field strength of 1.0 tesla, the approximate T2 relaxation time for renal cortex tissue is ______________. A. 45 ms B. 50 ms C. 60 ms D. 70 ms
D. 70 ms
At a field strength of 1.0 tesla, the approximate T2 relaxation time of fat is ________. A. 40 ms B. 50 ms C. 80 ms D. 90 ms
D. 90 ms
A saturation pulse is a technique used to reduce what type of motion artifact? A. Blood flow motion B. Respiratory motion C. Swallowing motion D. All of the above
D. All of the above
Ancillary equipment that should be excluded from the magnetic room includes which of the following? A. Ferrous oxygen tanks B. Battery powered IV pumps C. Ferrous scissors, pens, and hemostats D. All of the above
D. All of the above
Ancillary equipment that should be included in an MRI department includes which of the following? A. Non-ferrous wheelchair or stretcher B. Proper monitoring equipment for sedated patients C. A crash cart for emergency situations D. All of the above
D. All of the above
Biological effects associated with exposure to static magnetic fields above 2 Tesla include which of the following? A. Fatigue B. Headaches C. Hypotension D. All of the above
D. All of the above
Complete medical history should include which of the following? A. Patient age, sex, and weight B. Current physical symptoms C. Previous surgeries and associated medical problems D. All of the above
D. All of the above
During peak systolic phase of the cardiac cycle, blood flow velocities are dependent upon what factor(s)? A. Patients age B. Cardiac output C. Anatomical site D. All of the above
D. All of the above
Metal implants within the body, depending on the location, can pose what type of problems during the MRI exam? A. Torque B. Heating C. Artifacts D. All of the above
D. All of the above
Phase mismapping artifact caused by respiratory motion can be decreased by which method? A. Presaturation pulse B. Swapping phase and frequency direction C. Respiratory compensation D. All of the above
D. All of the above
Proper patient screening should include which of the following? A. The elimination of any loose metal objects and personal items B. The identification of any possible contraindications C. The identification of any biomedical implants D. All of the above
D. All of the above
Specific absorption rate is dependent upon which factor(s)? A. Induced electrical field and tissue density B. Patient size and pulse duty cycle C. Tissue conductivity D. All of the above
D. All of the above
The effects of entry slice phenomenon are dependent upon which factor(s)? A. Repetition time B. Slice thickness C. Velocity of flow D. All of the above
D. All of the above
The force on a ferromagnetic object placed in a magnetic field is dependent upon which of the following factors? A. The mass of the object B. The distance from the magnet C. The objects orientation to the magnet D. All of the above
D. All of the above
The magnitude of time of flight phenomenon effects is dependent upon which factor(s)? A. Velocity of flow B. TE C. Slice thickness D. All of the above
D. All of the above
Thorough patient preparation should include which of the following? A. Proper patient screening B. Complete patient medical history C. Adequate patient education D. All of the above
D. All of the above
What is an example of phase mismapping artifact? A. Cardiac motion B. Flow motion C. Respiratory motion D. All of the above
D. All of the above
Which of the following ancillary staff should be trained in the safety procedures of the MRI department? A. Janitorial staff B. Nursing staff C. MRI department clerical staff D. All of the above
D. All of the above
Which of the following hazards can occur due to an improperly ventilated quench? A. Frostbite due to decrease room temp B. Hearing loss due to increased air pressure in the scan room C. Patient suffocation due to loss of oxygen D. All of the above
D. All of the above
Which of the following objects should not be permitted past the 5 gauss line? A. Cardiac pacemaker B. Hearing aids C. Neuro stimulators D. All of the above
D. All of the above
Which of the following objects will be affected by a magnetic field of 10 gauss or higher? A. Video cameras B. Monitors C. Cameras D. All of the above
D. All of the above
Which of the following patients should be monitored with a pulse oximeter during an MRI procedure? A. Sedated patients B. Unconscious patients C. Patients with weak voices or hearing problems D. All of the above
D. All of the above
Which of the following pieces of equipment should be used and or available when sedating patients for an MRI exam? A. Pulse oximeter B. Blood pressure monitor C. Crash cart D. All of the above
D. All of the above
Biological effects associated with exposure to radio frequency include which of the following? A. Induction of electrical currents in tissue B. Heating due to tissue resistance C. Radiation poisoning D. Both A and B
D. Both A and B
To minimize MRI contrast agent's toxicity, the agent should be ________. A. Excreted intact by the kidneys B. Excreted intact by the gallbladder and intestines C. Released within the body D. Both A and B
D. Both A and B
Adequate patient education should include which of the following? A. Thorough description of the procedure B. Complete physics review C. The importance of remaining still D. Both A and C
D. Both A and C
Biological effects associated with exposure to static magnetic fields below 2 Tesla include which of the following? A. Increased amplitude at the T wave on an EKG B. Nausea and vomiting C. Minimal increase in body temperature D. Both A and C
D. Both A and C
Which of the following is a requirement for a chemical before it can be used as an MRI contrast medium? A. It must decrease magnetic relaxation times B. Must be non-ionic C. Must be biologically compatible with the human body D. Both A and C
D. Both A and C
Which of the following is an important environmental consideration necessary to maintain proper computer and gradient function? A. Temperature B. Barometric pressure C. Humidity D. Both A and C
D. Both A and C
Which of the following people won the 1952 Nobel Prize for their NMR research? A. Felix Bloch B. I.I. Rabi C. Edward Purcell D. Both A and C
D. Both A and C Felix Bloch and Edward Purcell
The first whole body MRI scanner was constructed at which of the following facilities? A. Harvard University Medical Center B. Stanford University Medical Center C. Yale University Medical Center D. Downstate Medical Center, New York
D. Downstate Medical Center, New York
The signal created after applying a 90 degree RF pulse is known as a ____________. A. gradient echo signal B. spin echo signal C. spin spin signal D. FID signal
D. FID signal
The first intravenous MRI contrast agent that was used on a human subject was known as ______. A. Niobium-titanium B. Ferric chloride C. Ferric nitrate D. Gadopentetate dimeglumine
D. Gadopentetate dimeglumine
The coils used to alter the magnetic field during scanning are known as the ________________. A. RF receive coils B. RF transmit coils C. Shim coils D. Gradient coils
D. Gradient coils
Which of the following people was attributed in 1967 with producing the first MR signals from a live animal? A. Edward Purcell B. Felix Bloch C. Paul Lauterbur D. Jasper Jackson
D. Jasper Jackson
Which of the following people developed the complex mathematical formulas used in MRI to reconstruct signals into images? A. Michael Faraday B. Nikola Tesla C. Niels Bohr D. Jean Baptiste Joseph Fourier
D. Jean Baptiste Joseph Fourier
The area within the array processor where spatially located information is stored is known as __________. A. interspace B. array space C. fourier space D. K space
D. K space
What is an example of aperiodic motion? A. Cardiac motion B. Flow motion C. Respiratory motion D. Peristalsis motion
D. Peristalsis motion
An image artifact caused by anatomical motion along a gradient is known as what type of artifact? A. Ringing B. Aliasing C. Volume averaging D. Phase mapping
D. Phase mapping
Blood flow that slows to a point of immobility is known as what type of flow? A. Turbulent flow B. Laminar flow C. Vortex flow D. Stagnant flow
D. Stagnant flow
Figure 3-6 displays which type of relaxation curve? A. T1 relaxation curve B. inversion recovery curve C. T2 relaxation curve D. T2* relaxation curve
D. T2* relaxation curve
Which of the following vessels has the slowest peak velocity? A. Ascending aorta B. Middle cerebral arteries C. Proximal carotid arteries D. Venous vessels
D. Venous vessels
The magnetic properties of the nucleus of atoms were discovered in 1924 by which of the following people? A. Edward Purcell B. Raymond Damadian C. Joseph Henry D. Wolfgang Pauli
D. Wolfgang Pauli
Chemical shift artifact can be minimized by which of the following methods? A. minimizing the FOV B. increasing the receive bandwidth C. utilizing chemical saturation D. all of the above
D. all of the above
Cross excitation artifact can be eliminated by which of the following methods? A. increasing interslice gap B. using a sinc RF pulse C. interleaving D. all of the above
D. all of the above
During cardiac gating, which factors are affected by having an effective TR? A. image weighting B. number of slices C. scan time D. all of the above
D. all of the above
Foldover artifact in the phase direction can be corrected by which of the following methods? A. oversampling signal outside the FOV B. increasing FOV C. using saturation pulses outside the FOV D. all of the above
D. all of the above
In an MR image, the degree of chemical shift artifact depends upon which parameter? A. receive bandwidth B. size of the FOV C. magnetic field strength D. all of the above
D. all of the above
In clinical MRI, which of the following is a disadvantage of using a superconducting magnet? A. high capital costs B. high fringe field C. high cryogenic costs D. all of the above
D. all of the above
In clinical MRI, which of the following is an advantage of using a superconducting magnet? A. high field strength B. short scan times C. low power consumption D. all of the above
D. all of the above
Prior to each scan, the process of prescanning performs which type of calibration? A. adjusts the transmit gain B. adjusts the receive attenuation C. sets the center frequency D. all of the above
D. all of the above
The artifact that appears as a low intensity band in areas of high intensity due to undersampling is known as _________. A. Gibbs artifact B. truncation artifact C. ringing artifact D. all of the above
D. all of the above
The gradient echo pulse sequence that produces true T2 image weighting is known as ____________. A. SSFP B. T2 FFE C. PSIF D. all of the above
D. all of the above
The height and width of a picture element is determined by what parameter(s)? A. size of the FOV B. number of phase encoding steps C. number of frequency encoding steps D. all of the above
D. all of the above
The number of times each signal is sampled with the same value of the phase encoding gradient is known as ___________. A. number of signal averages B. number of excitations C. number of signal quotients D. all of the above
D. all of the above
The return of longitudinal magnetization to equilibrium is known as ___________. A. T1 relaxation B. spin-lattice relaxation C. longitudinal relaxation D. all of the above
D. all of the above
When the radio frequency is turned off, precessing nuclei begin to ________________. A. relax B. lose energy C. dephase D. all of the above
D. all of the above
Which area outside the blood brain barrier shows normal enhancement with the injection of gadolinium? A. choroid plexus B. pineal gland C. pituitary gland D. all of the above
D. all of the above
Which of the following is a clinical indication for the use of MRI contrast agents? A. CNS tumors B. post surgical lumbar discs C. infection D. all of the above
D. all of the above
Which of the following is a disadvantage of TOF MRA? A. parallel flow can be suppressed B. slow flow can be suppressed C. stationary tissue with short T1 relaxation times can produce signal D. all of the above
D. all of the above
Which of the following is a disadvantage of a gradient echo pulse sequence? A. decreased signal to noise ratio B. increased sensitivity to magnetic susceptibility artifacts C. increased gradient noise D. all of the above
D. all of the above
Which of the following is a parameter that directly affects signal to noise ratio? A. voxel size B. number of excitations C. repetition time D. all of the above
D. all of the above
Which of the following is a possible side effect of gadopentetate dimeglumine? A. mild, temporary headaches B. nausea C. vomiting D. all of the above
D. all of the above
Which of the following is a precaution for the use of gadolinium? A. patients with sickle cell anemia B. patients with a history of grand mal seizures C. patients with a history of asthma D. all of the above
D. all of the above
Which of the following is an advantage of TOF MRA? A. Relatively short scan times B. increased sensitivity to flow C. decreased sensitivity to intra-voxel dephasing D. all of the above
D. all of the above
Which of the following is an advantage of a fast spin echo pulse sequence? A. reduced scan times B. improved quality C. increased T2 weighting D. all of the above
D. all of the above
Which of the following is an advantage of gradient echo pulse sequences? A. decreased scan time B. increased sensitivity to flow C. volume acquisitions possible D. all of the above
D. all of the above
Which of the following is an advantage of phase contrast MRA? A. increased stationary tissue suppression B. sensitive to flow in all directions C. sensitive to flow with various velocities D. all of the above
D. all of the above
Which of the following is an example of a non-neoplastic disease of the brain that enhances with the injection of gadolinium? A. meningitis B. demyelinating disease C. cerebral infection D. all of the above
D. all of the above
Which of the following pathologies of the spine is an indication for the use of an MRI contrast agent? A. spinal cord infection B. recurrent disc herniation C. intramedullary neoplasm D. all of the above
D. all of the above
Which parameter(s) effect total scan time? A. repetition time B. number of phase encoding steps C. number of excitations D. all of the above
D. all of the above
The spin of the proton of the hydrogen atom is known as _____________. A. nuclear spin B. axial momentum C. hydraulic spin D. angular momentum
D. angular momentum
A voxel that is unequal in height, width, and depth is known as ____________. A. isotropic B. triangular C. square D. anisotropic
D. anisotropic
Another name for a proton density weighted image is ___________. A. spin density B. intermediate C. inversion recovery D. both A and B
D. both A and B
During cardiac gating, TR is dependent upon which factor(s)? A. the patient's heart rate B. the R-R interval C. the Q-R interval D. both A and B
D. both A and B
In MR imaging, the interslice gap is determined by which factor(s)? A. slice selection gradient slope B. slice thickness C. external magnetic field strength D. both A and B
D. both A and B
Magnetization in the longitudinal plane can also be known as ____________. A. Mz B. equilibrium C. Mxy D. both A and B
D. both A and B
The osmolality of a contrast agent is measured in what unit? A. osmoles per kilogram of water (Osm/kg) B. milliosmoles per kilogram of water (mOsm/kg) C. milliliters per kiloliter (ml/kl) D. both A and B
D. both A and B
The type of pulse sequence that uses only 90 degree RF pulses is known as _________. A. partial saturation pulse sequence B. gradient echo pulse sequence C. saturation recovery pulse sequence D. both A and B
D. both A and B
Which of the following is a disadvantage of fast spin echo pulse sequences? A. increased effects of flow motion B. bright fat on T2 weighted images C. increased resolution D. both A and B
D. both A and B
Which of the following is a method used in MRA to suppress stationary tissue? A. tissue subtraction B. tissue saturation C. bipolar gradient D. both A and B
D. both A and B
Wraparound artifact occurs in which direction of an MR image? A. phase direction B. frequency direction C. slice selection direction D. both A and B
D. both A and B
Another name for aliasing artifact is ____________. A. foldover artifact B. ringing artifact C. wraparound artifact D. both A and C
D. both A and C
During the sampling of signal, the sampling time is inversely proportional to __________. A. sampling rate B. transmit bandwidth C. receive bandwidth D. both A and C
D. both A and C
Figure 6-2 displays an example of what type of artifact? A. magnetic susceptibility B. phase wrap C. RF zipper D. both A and C
D. both A and C
Gradient echo pulse sequence that have incoherent residual transverse magnetization are primarily used to create what type of image weighting? A. T1 weighting B. T2 weighting C. proton density weighting D. both A and C
D. both A and C
Gradient moment nulling is most effective in reducing flow related motion in which type of flow? A. slow flow B. fast flow C. inplane flow D. both A and C
D. both A and C
Shading artifact can be caused by what factor(s)? A. inhomogeneity of the external magnetic field B. undersampling of phase encoding steps C. inhomogeneity of the RF pulse D. both A and C
D. both A and C
The number of 180 degree rephasing pulses performed in a fast spin echo pulse sequence is known as its __________. A. turbo factor B. inversion factor C. echo train length D. both A and C
D. both A and C
The precessional frequency of magnetic nuclei is determined by which of the following? A. the strength of the external magnetic field B. the magnetogyric frequency C. the gyromagnetic ratio of the specific nuclei D. both A and C
D. both A and C
The process of filling k space by sampling only half of the echo and interpolating the rest is known as _______. A. fractional echo B. gradient echo C. partial echo D. both A and C
D. both A and C
The thickness of an MRI image can be changed by which of the following methods? A. altering the gradient slope B. changing the number of excitations C. altering the RF bandwidth D. both A and C
D. both A and C
The use of an additional gradient to correct the effects of intra-voxel dephasing is a technique known as ___________. A. gradient moment rephasing B. intra-voxel misregistration C. gradient moment nulling D. both A and C
D. both A and C
Which of the following conventional MRI techniques can be used to produce contrast differences between vascular structures and stationary structures? A. gradient moment nulling B. respiratory compensation C. pre-saturation pulse D. both A and C
D. both A and C
Which of the following is a disadvantage of phase contrast MRA? A. long scan times B. reduced intra-voxel dephasing C. increased sensitivity to turbulence D. both A and C
D. both A and C
Which of the following is a method of eliminating residual transverse magnetization? A. digital RF spoiling B. gradient rewinding C. gradient spoiling D. both A and C
D. both A and C
Which of the following is a method used in MRA to increase signal from vascular structures? A. gradient moment nulling B. subtraction C. bipolar gradient D. both A and C
D. both A and C
Which of the following is a type of image that is produced by phase contrast MRA? A. magnitude image B. frequency image C. phase image D. both A and C
D. both A and C
Which of the following is an example of an extra axial neoplasm? A. meningioma B. astrocytoma C. acoustic neuroma D. both A and C
D. both A and C
Which of the following is the equation that is used to determine precessional frequencies? A. Wo=yBo B. Bo=yWo C. F=yBo D. Both A and C
D. both A and C
A spin echo image with a long TR and a short TE is known as what type of image? A. T1 weighted image B. proton density weighted image C. spin density weighted image D. both B and C
D. both B and C
Alignment of the net magnetic vector in the direction of the external magnetic field is known as ______________. A. transverse magnetization B. longitudinal magnetization C. equilibrium D. both B and C
D. both B and C
Another name for truncation artifact is ___________. A. foldover artifact B. Gibbs artifact C. ringing artifact D. both B and C
D. both B and C
Gradient strength is measured in what form of unit? A. megahertz B. gauss per cm C. millitesla per meter D. both B and C
D. both B and C
In MR imaging, slice thickness is determined by which factor(s)? A. magnet field strength B. gradient slope slice select C. transmit bandwidth D. Both B and C
D. both B and C
MRI signals can only be detected in which of the following planes? A. Z plane B. XY plane C. transverse plane D. both B and C
D. both B and C
Magnetization in the transverse plane can also be known as _________________. A. Mz B. Mxy C. Mo D. Both B and C
D. both B and C
The ratio that describes the constant at which any magnetic nucleus will precess in a 1 tesla magnet is known as ___________. A. precessional ratio B. magnetogyric ratio C. gyromagnetic ratio D. both B and C
D. both B and C
The spin echo pulse sequence that performs more than one phase encoding step per TR is known as ______. A. conventional spin echo B. fast spin echo C. RARE D. both B and C
D. both B and C
The type of magnet that is produced by passing an electrical current through a conductor is known as _____. A. permanent magnet B. resistive magnet C. electromagnet D. both B and C
D. both B and C
In fat, the hydrogen atom is bound with what other type of atom? A. oxygen B. nitrogen C. helium D. carbon
D. carbon
Blood flow that travels in the same direction in which the slices are acquired is known as what type of flow? A. counter current flow B. vortex flow C. stagnant flow D. co-current flow
D. co-current flow
Figure 6-5 displays an example of what type of artifact? A. truncation B. aliasing C. cross excitation D. chemical shift
D. cross excitation
Isolating the RF transmitter from the RF receiver is known as __________. A. deisolation B. isolation C. coupling D. decoupling
D. decoupling
Material that is slightly repelled from a magnetic field is said to be ________. A. resistive B. paramagnetic C. ferromagnetic D. diamagnetic
D. diamagnetic
Materials reach their highest magnetic potential when their atoms are grouped in areas known as _________. A. regions B. fields C. fringes D. domains
D. domains
The law that is used in MRI to describe how a magnetic field is induced by flowing current is known as ____________. A. damadian's law B. murphy's law C. newton's law D. faraday's law
D. faraday's law
Aliasing artifact in the frequency direction can be corrected by which of the following methods? A. decreasing FOV B. increasing matrix C. filtering the frequencies outside the FOV in the phase direction D. filtering the frequencies outside the FOV in the frequency direction
D. filtering the frequencies outside the FOV in the frequency direction
The type of coils used to change the strength of the magnetic field inside the bore of the magnet are known as __________. A. RF coils B. shim coils C. surface coils D. gradient coils
D. gradient coils
Figure 5-4 is a diagram showing what type of pulse sequence? A. partial saturation B. spin echo C. inversion recovery D. gradient echo
D. gradient echo
The type of pulse sequence that uses a gradient instead of a 180 degree RF pulse to rephase dephasing nuclei is known as ___________. A. spin echo B. inversion recovery C. fast spin echo D. gradient echo
D. gradient echo
The specific liquids used to maintain low temps in the superconducting magnet wire are __________. A. titanium, niobium B. hydrogen, neon C. halon, oxygen D. helium, nitrogen
D. helium and nitrogen
Magnetic susceptibility artifact can be used to help diagnose what pathology? A. torn meniscus B. herniated nucleus pulposis C. pituitary adenoma D. hemorrhage
D. hemorrhage
Data loss due to gradient instability, excessive noise, or tuning errors can cause an artifact with what type of appearance? A. zippering B. shading C. staring D. herringbone
D. herringbone
Clinical MRI is based on the generation of signal from the nucleus of which atom? A. helium B. nitrogen C. oxygen D. hydrogen
D. hydrogen
In which of the following types of flow can intra-voxel dephasing be compensated for? A. turbulent flow B. vortex flow C. stagnant flow D. laminar flow
D. laminar flow
The equation that is used to determine the precessional frequency of magnetic nuclei is known as __________. A. faraday's equation B. fast fourier transformations C. damadian's equation D. larmor equation
D. larmor equation
With the parameters given, which protocol has the longest acquisition time? A. long TR/low NEX/low matrix B. short TR/high NEX/low matrix C. short TR/low NEX/high matrix D. long TR/high NEX/high matrix
D. long TR/high NEX/high matrix
With the parameters given, which protocols gives the highest signal to noise ratio? A. long TR/short TE/high matrix B. short TR/long TE/low matrix C. long TR/long TE/high matrix D. long TR/short TE/low matrix
D. long TR/short TE/low matrix
Gadoteridol, also known as ProHance, is based on what type of molecular structure? A. linear ionic B. linear nonionic C. macrocyclic ionic D. macrocyclic nonionic
D. macrocyclic nonionic
Figure 6-1 displays an example of what type of artifact? A. aliasing B. truncation C. foldover D. magnetic susceptibility
D. magnetic susceptibility
Metal in the patient, in the area that is being scanned, will most likely create what type of artifact? A. foldover artifact B. chemical shift artifact C. truncation artifact D. magnetic susceptibility
D. magnetic susceptibility
In a T2 weighted image, a long TR is used to __________. A. maximize T2 effects B. minimize T2 effects C. maximize T1 effects D. minimize T1 effects
D. minimize T1 effects
The sum of all of the unmatched parallel protons in an external magnetic field makes up what is called the ________. A. external magnetization B. internal magnetization C. resonant magnetization D. net magnetic vector
D. net magnetic vector
With the exception of hydrogen, all matter is composed of three components. They are _____________. A. electrons, photons, protons B. electrons, neutrons, photons C. protons, neutrons, photons D. neutrons, electrons, protons
D. neutrons, electrons, protons
The wire used to create the main magnetic field in a superconducting magnet is known as ____________. A. aluminum-tiobium B. iron sulfite C. copper-tungsten D. niobium-titanium
D. niobium-titanium
Which of the following is a contraindication for the use of gadolinium? A. patients with a history of metastatic cancer B. patients with history of asthma C. patients with history of metal implants D. no known contraindications
D. no known contraindications
The type of magnet that is produced by permanently magnetizing a ferromagnetic substance is known as a ___________. A. resistive magnet B. electromagnet C. superconducting magnet D. permanent magnet
D. permanent magnet
Figure 6-6 displays an example of what type of artifact? A. aliasing B. truncation C. chemical shift D. phase mismapping
D. phase mismapping
The nucleus of the hydrogen atom is made up of one _______. A. neutron B. electron C. photon D. proton
D. proton
In a superconducting magnet, the sudden loss of superconductivity is known as ___________. A. squelch B. slouch C. screech D. quench
D. quench
A 180 degree RF pulse is used to ___________ the dephasing net vector in the transverse plane. A. magnetize B. decay C. delay D. refocus
D. refocus
When the proper radio frequency is applied, the precessing hydrogen nuclei begin to ___________. A. dephase B. rephase C. relax D. resonate
D. resonate
Coils used to correct imperfections in the magnetic fields are known as __________. A. RF coils B. surface coils C. gradient coils D. shim coils
D. shim coils
The process of adjusting coils to improve the homogeneity of the external magnetic fields is known as __________. A. strengthening B. fringing C. shielding D. shimming
D. shimming
In a T1 weighted image, fat has a ____________ T1 relaxation time and therefore appears __________. A. long, bright B. long, dark C. short, dark D. short, bright
D. short, bright
The depth of a volume element is determined by what parameter? A. matrix B. NEX C. repetition time D. slice thickness
D. slice thickness
Dephasing of the net vector in the transverse plane is known as _____________. A. T1 relaxation B. spin-lattice relaxation C. longitudinal relaxation D. spin-spin relaxation
D. spin-spin relaxation
The type of MRI magnet that is produced by cooling a current down to 4 degrees Kelvin is known as ______. A. distractive magnet B. permanent magnet C. resistive magnet D. superconducting magnet
D. superconducting magnet
The type of magnet that is produced by removing resistance from a conductive wire is known as _______. A. resistive magnet B. reactive magnet C. permanent magnet D. superconducting magnet
D. superconducting magnet
With the parameters given, which protocol gives the highest spacial resolution? A. thick slice/large FOV/high matrix B. thin slice/large FOV/high matrix C. thin slice/small FOV/ low matrix D. thin slice/small FOV/high matrix
D. thin slice/small FOV/ high matrix
During cardiac gating, the waiting time before each R wave is known as _____________. A. repetition time B. inversion time C. trigger delay D. trigger window
D. trigger window
