Magnetic Resonance Imaging (MRI) Board Practice Exam

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• Among common MRI pulse sequences, which should be used least in a patient with implanted metallic hardware?
• The visual stimulation described as of seeing stars during MRI is known as
• The relaxation process that describes decay of transverse magnetization due to dephasing is called:
• The first documented human MR image was obtained on a 15 MHz RF system. What field strength did it operate at?
• What term denotes loss of spatial resolution due to excessively large voxels, typically from thick slices?
• According to the Larmor equation, the precessional frequency is proportional to what quantity?
• If the field of view is doubled while the matrix remains constant, the pixel size will:
• What is true about the use of shielding in MR facilities?
• In a 3D MRI acquisition with a 240 mm field of view and a 272 x 272 matrix, what is the approximate in-plane pixel size?
• Which parameter is most associated with image blur in fast spin-echo sequences?
• What is the designation for the static main magnetic field of an MR scanner?
• Which two parameters primarily determine the in-plane pixel size of an MRI image?
• T1 weighting is achieved by using a short TE and short TR.
• Assuming all other parameters are the same, which TR value provides the best signal-to-noise ratio?
• Gadolinium-enhanced MRI is most directly used to indicate what pathology?
• Letter A in Image 101 points to which MR artifact?
• Which artifact occurs because of chemical misregistration?
• What is the Larmor frequency for Hydrogen at 0.5 Tesla?
• 2D acquisitions usually require which of the following?
• Calculate the pixel area for the following sequence: TR 450, TE 12, FOV 18 cm, 224 x 256 matrix, 4 NEX.
• Column B in Image 111 corresponds to which MRI pulse sequence?
• Which MR technique quantitatively assesses the mechanical properties of tissues based on the propagation of shear waves?
• Which MR angiography method uses intravenously injected gadolinium to shorten T1 and highlight vessels?
• The SI unit of magnetic field strength is named after which scientist?
• In which year did Schering's Magnevist IV Gadolinium contrast gain FDA approval?
• When acquiring ACR QA data, the slice correlating to Image 213 requires what visual discernment?
• IV gadolinium contrast administration is indicated for which system?
• T2 FLAIR sequences are particularly helpful because they suppress which signal?
• Lowering the receiver bandwidth lengthens the minimum TR and TE.
• Which stage of disease is characterized by the absence of symptoms?
• Who discovered that a current flowing through a wire could produce a magnetic field?
• Which MRA technique relies on flow-related enhancement to distinguish stationary spins from flowing spins?
• Proton Density weighting emphasizes which tissue property?
• Fat suppression in STIR imaging with TI of 160 ms is achieved optimally at which field strength?
• If you keep thickness and gap fixed but increase the number of slices, what happens to total anatomical coverage?
• Which combination of flip angle and TR would produce a T2 weighted gradient echo?
• Which statement correctly defines repetition time (TR)?
• Which axis gradient corresponds to encoding along the left-right direction?
• Which MRI parameter primarily controls T1 relaxation contrast?
• Increasing the receiver bandwidth decreases chemical shift artifacts.
• A FID is produced from:
• What formula is used to calculate the size of the pixel?
• Who discovered and developed the first rotating magnetic field?
• Enteral routes of drug administration include all of the following EXCEPT:
• In one T1 relaxation time, what percent of longitudinal magnetization has recovered?
• Which term denotes the static magnetic field strength that defines the MR system's baseline field?
• In an inversion recovery sequence, which RF pulse inverts the magnetization?
• In magnetic resonance imaging, which relaxation times are commonly used to distinguish tissue types?
• The statement “An example of a parenteral method of drug delivery is taking a drug by mouth” is true or false?
• The time during which the frequency encoding gradient is on increases with a reduction in receiver bandwidth.
• What is the correct scan time for a spin echo sequence with TR 500 ms, TE 30 ms, matrix 208 x 208, 2 NEX, FOV 200 mm?
• In acquiring ACR QA data, Image 210 is used to evaluate for what quality measure?
• Which of the following parameter combinations would yield the most T2 weighted image?
• Which parameter is NOT affected by changing the slice thickness?
• Gadolinium-based contrast agents primarily shorten which MR relaxation time, enabling enhancement on T1-weighted images?
• TE in MRI stands for which term?
• When thermal equilibrium is reached, there are more hydrogen protons in which energy state?
• A T2 weighted image will have a repetition time (TR) in the range of:
• Which factor does not affect voxel volume?
• In Proton Density weighting, TR is chosen to minimize which type of contrast?
• A more accurate method for detecting small intra-ocular ferrous foreign bodies is
• What uncharged neutral particle located in the nucleus of most atoms serves as a stabilizer?
• Which artifact arises from the interference of aliased signals at different phase-encoding steps?
• What does the maximum intensity projection (MIP) algorithm do?
• To maximize T1 weighting, you should use a short TE and short TR.
• In a 3D volume acquisition, SNR would increase with an increase in which of the following?
• Through which vessel does the Sylvian fissure have a key arterial course?
• Which statement best describes how Larmor frequency relates to magnetic field strength?
• For a recFOV twice as tall as wide and phase encoding along the smaller width dimension, which relationship between phase steps and frequency steps yields square pixels?
• T1 time is EXTRINSIC or INTRINSIC
• During dissection, which artery is found traversing the Sylvian fissure?
• T2-weighted sequences yield hyperintense signal from which type of tissue change?
• For sedated patients during MRI, which monitoring method is essential to assess oxygenation?
• What signal characteristic does an FDA-approved oral contrast agent for MRI typically produce in bowel imaging?
• Decreasing the slice selection gradient strength will ________ of the resulting slice.
• How well a material attracts the imaginary lines of the magnetic field is defined as:
• What is the primary signal detected in MRI called?
• If a sagittal slice plane is selected, which gradient is enabled to alter the magnetic field around the patient's body?
• VoLumen is a contrast agent used for which purpose?
• Which column in Image 112 corresponds to the same sequence as Column A in Image 111?
• Which slice orientation results from applying two gradient axes during slice selection?
• What is the name of the resonant frequency that equals the magnetic field multiplied by the gyromagnetic ratio?
• A decrease in the voxel volume yields:
• Who developed the equation showing precession of nuclear spins being proportional to magnetic field strength?
• The term for disease-causing agents is most accurately described as?
• Which doctrine is described as 'the thing speaks for itself' and permits the presumption of negligence without direct evidence of behavior?
• The artifact that arises when tissue signals are misregistered along fat and water is called:
• The timing of RF pulses in an MRI pulse sequence controls:
• In what year did Damadian and his team construct the first superconducting NMR scanner and produce the first image of the human thorax?
• SNR increases with all the following adjustments, EXCEPT:
• The artifact in Image 101 is caused by?
• Which weighting is best suited to highlight edema as bright signal?
• LPM stands for which of the following?
• What determines the amount of T1 weighting in an image?
• Which artifact is most closely associated with coil channels outside the imaging field of view and can be mitigated by de-selecting those channels?
• Letter C in Image 73 represents which component?
• __________ is defined as a small change in the magnetic field along a particular axis.
• TE in MR imaging stands for which parameter?
• Which statement best defines the Ernst angle?
• In MRI terminology, TE stands for which of the following?
• The cause or origin of a disease is defined as what?
• What is the per kilogram dose used in the example to derive the 16 mL total for an 80 kg patient?
• The magnetohydrodynamic effect is associated with changes in which ECG waveform?
• Which sequence is explicitly described as having fat suppression through inversion recovery?
• Partial saturation yields T1 weighting; occurs when NMV is 180°
• Doubling the magnetic field strength will:
• If the receiver bandwidth is decreased, the sampling rate
• In Image 76, Letter E corresponds to which signal type?
• Which tissue property leads to brightness on a T1-weighted spin echo image?
• A field strength of 1.5 Tesla is typically categorized as which level of field strength in MRI?
• In a spin echo pulse sequence, an echo is produced from which of the following?
• A technique utilized to reduce the MRI scan time which requires the use of an array coil is
• Which sequence provides proton density contrast?
• A magic angle artifact occurs when a tendon or ligament is oriented approximately what angle to the main magnetic field, typically with a short TE sequence?
• The readout gradient is typically activated during sampling of the peak echo and also during which process?
• Which substance is NOT ferromagnetic?
• Increasing TE in a spin-echo sequence primarily increases which type of contrast?
• K-space is typically filled:
• What would NOT compensate for the change in signal-to-noise as a result of decreasing the FOV?
• Which expression represents the calculation for anatomic slice coverage?
• Multiple coil elements combined with multiple receiver channels make a:
• Damadian and his team produced the first MRI image of the human thorax using what device?
• The 180º RF pulse used for refocusing spins is described as which?
• Which statement about SAR risk factors is accurate?
• The artifact described as dielectric effects is best seen as shading or signal changes due to RF field inhomogeneity. Which artifact is this?
• Which MR technique provides a spectrum of metabolites within a voxel rather than an image?
• In a spin echo sequence, the 180° RF refocusing pulse serves to:
• What is the clinical-use static field limit stated by the FDA for patients older than one month?
• Chemical shift artifacts occur along which encoding axis?
• High-contrast spatial resolution QA imaging is used to evaluate which quality measure?
• Which of the following is NOT a non-ferrous substance?
• Post-contrast imaging is typically performed with which type of sequence to assess enhancement?
• T1 is useful for __________, whereas T2 is utilized for depicting __________.
• The ______________ is the speed rate of ascent or descent of a gradient from zero to its maximum amplitude, either positive or negative
• In a Fast Spin Echo sequence, the effective TE are the echoes that are encoded:
• The Ernst angle is defined as the optimal ___________ that yields the ____________ signal for a particular spin in the least amount of time.
• When moving blood enters a magnetic field during MRI, which ECG phenomenon may occur?
• Which set of images is produced to map diffusion properties in tissues by using diffusion weighted imaging with multiple b-values?
• The coil construction in an MR system, from the innermost aspect to the outer:
• Image 87 displays which type of artifact?
• Which patients are most likely to have a potentially serious reaction to gadolinium?
• Which sequence provides primarily T1-weighted contrast?
• Which column in Image 109 corresponds to the same sequence as Column A in Image 112?
• A T1 weighted image will have a repetition time (TR) in the range of:
• Which MRI sequence suppresses fat signal and bone marrow with bright fluid?
• Which sequence uses inversion recovery to suppress fat signal?
• Which type of material aligns readily with an external magnetic field due to unpaired electrons and exhibits strong magnetization?
• In MRI, what primarily controls image contrast in a given pulse sequence?
• As the TR is increased, which of the following statements are true?
• An isotropic voxel has equal measurements in all three dimensions. Given FOV divided by matrix equals 1.25 mm, which statement is true?
• What occurs after the initial RF pulse that causes phase dispersion among spins and decay of transverse magnetization?
• Which parameter is used in routine QA to verify coil tuning and magnetic field consistency?
• In Proton Density weighting, TE is chosen to minimize which type of contrast?
• Decreasing the field of view (FOV) will have which effect on spatial resolution?
• Which technique reduces MRI scan time by using an array coil and is commonly employed in modern scanners?
• Which column in Image 111 corresponds to the same sequence as Column C in Image 112?
• What term is defined as the magnitude and direction of the magnetization resulting from the collection of atomic nuclei?
• The ____________ is responsible for the knocking noise the system makes while the sequence is in progress.
• The signal produced immediately following an RF pulse is:
• Which gradient is used to select a specific slice during acquisition?
• Which process describes the decay of transverse magnetization due to phase dispersion after RF excitation?
• The 2D NMR technique introduced in 1975 uses phase and frequency encoding and which mathematical transform?
• As the number of excitations (NEX) increases from 1 to 3, which of the following does NOT occur?
• FDA's intensity limit for the static magnetic field for the entire population is:
• The 90º RF excitation pulse is used to do what in MRI sequences?
• Increasing the TE has which effects?
• DCE refers to:
• If the matrix is increased from 256 x 256 to 512 x 512 while keeping FOV constant, what happens to the pixel size?
• _________ is a file on the computer where the collected echoes are stored prior to being processed into an image by the Fourier Transform.
• Which of the following's primary biological effect is tissue heating/deposition?
• In Image 76, Letter C corresponds to which gradient?
• Which statement about signal depth with a 6 inch surface coil is consistent with the provided data?
• NSA stands for which of the following?
• Which MR technique uses the propagation of shear waves to assess tissue mechanical properties?
• To reduce chemical shift artifacts in MRI, which parameter should be increased?
• Narrowing the receiver bandwidth tends to worsen which artifact most notably?
• If the slice thickness is reduced, what is the expected effect on SNR?
• In gradient echo sequences, what is the effect of reducing the flip angle while TR is fixed?
• Which major cerebral artery is closely associated with the Sylvian fissure?
• The strength of the gradient magnetic fields are measured in which units?
• The _____ is located within an equipment room.
• In Image 76, Letter A corresponds to which component in the MRI sequence diagram?
• After one T1 relaxation time, what percent of longitudinal magnetization remains unrecovered?
• Which parameter will provide the better spatial resolution?
• In order to produce an echo in a gradient echo pulse sequence, a ___________ is used.
• In one T2 relaxation time, what percent of transverse magnetization decays?
• After one T2 relaxation time, what percent of transverse magnetization remains?
• A magnetic vector possesses attributes of both:
• If the main field strength is doubled, what is the expected impact on SAR potential?
• Given a TR of 32 ms, TE 4 ms, Flip Angle 15°, FOV 18 cm, 2 mm slices, 96 slices, 192 x 256 matrix, and 1 NEX, what is the approximate 3D scan time?
• In a spin echo sequence, the time between the 90° RF pulse and the 180° RF pulse is known as the:
• FDA's intensity limit for the static magnetic field in clinical use for patients older than one month is:
• During a quench, patients and staff should be evacuated to prevent which hazards?
• A remedy for Gibbs truncation artifact would be to increase which parameter?
• Presaturation pulses typically are found in MRI sequences at which location?
• Which MR sequence uses long TE and long TI to suppress fluids?
• Per-slice anatomic coverage equals the sum of slice thickness and interslice gap. If thickness is 4 mm and gap is 1 mm, per-slice coverage is:
• Which term defines the range of frequencies encompassed by a pulse sequence as processed by the RF system?
• Which of the following is not a parenteral route of drug delivery?
• Contrast reactions are very rare in MRI injections; which is the most commonly reported contrast reaction?
• In emergency situations, a physician can order a procedure under what form of consent if the patient is unconscious?
• Which term can mean something that hinders or disadvantages an individual or group, or something someone is responsible for, or something that increases the likelihood of an event?
• When gradient moment nulling is used as an imaging option in MR sequences:
• In slice selection, the Larmor frequency is used together with which parameter to obtain a thin slice?
• What determines the amount of T2 weighting in an image?
• What QA/QC indicator tests the accuracy of the magnetic field for coil tuning and consistent magnetic field strength?
• In a spin echo sequence, the time between the 90° and 180° pulses is commonly referred to as:
• Which of the following is NOT a magnetic field associated with MR imaging?
• Which gradient encodes information along the phase-encoding direction?
• Who developed equations describing how electric and magnetic fields are generated and altered by each other?
• Enabling Driven Equilibrium will enable the operator to:
• Letter A in Image 73 represents which component?
• Which combination of T1 and T2 relaxation times does water typically have?
• Which materials, including iron, contain unpaired electrons that align readily with an external field?
• Which statement is true regarding TE and slice availability?
• MRI uses how many separate magnetic fields to perform routine image acquisition?
• The duty cycle can be viewed as the:
• Which mathematical operation converts frequency-domain data into a displayable image in MRI?
• Reducing the TR:
• TR is INTRINSIC or EXTRINSIC
• A T2 weighted image will have an echo time (TE) in the range of:
• Which gradient is used for slice selection during the excitation in an MRI pulse sequence?
• The FDA sets static magnetic field clinical use limits of what values for the entire population and for those over 1 month of age, respectively?
• Aliasing occurs because tissue outside the selected FOV is:
• Assuming all other parameters are the same, an echo time of ___________ ms provides the best Signal-to-Noise Ratio.
• At 1.5 Tesla, the fat-water chemical shift difference is approximately how many Hz?
• Edema appears hyperintense on which MRI weighting?
• Which sequence would be described as T2 weighted with fat suppression?
• In general, as TR increases, what happens to T1-weighted contrast?
• In k-space, which lines contain signal and contrast information?
• To increase voxel volume, which parameters would you adjust?
• Which sequence combines T2 weighting with fat suppression to improve lesion detection?
• Which sequence would be more at risk for the effects that time varying magnetic fields can cause?
• High amplitude signals are stored in which portion of k-space?
• Which material and shielding type pair is most commonly used to reduce the fringe field in MR facilities?
• In Image 77, Letter E represents which parameter?
• Which MR technique is used to image flowing blood and vascular structures?
• FDA safety guidelines address patient comfort by regulating which of the following MRI-related factors?
• What term describes a medical or psychological treatment guideline that specifies appropriate treatment based on scientific evidence and collaboration among medical professionals?
• Who coined the word "electricity" and was the first to realize that the Earth is a giant magnet?
• A T1 weighted image will have an echo time (TE) in the range of:
• How does increasing magnetic field strength affect chemical shift artifacts?
• The timing of the RF pulses in an MRI pulse sequence controls which aspect of the image?
• The CPU used to plot and adjust slices in an MR sequence is located in which area?
• Which term describes the data collected by the MR receiver before image reconstruction, stored as a function of time?
• Water is dark and fat is bright in:
• The central lines of k-space are associated with what type of information in a fast spin echo sequence?
• Which scientist published the first MRI image of a living human body part, specifically a finger?
• The gradient that is on during the production of the echo is the:
• Each train of echoes in a fast spin echo sequence has what effect on the sequence?
• To correct the artifact shown in Image 172, the technologist would?
• Image 79 is an example of which MR system?
• Aside from the center frequency, what indicator in Image 82 signifies it was acquired at 1.5 Tesla?
• Which setting is most directly altered to enhance T1 contrast in a spin-echo image?
• Which field strength would yield more chemical shift artifacts?
• Which TR range is most typical for proton density weighting?
• Which term defines a patient's permission to undergo a medical procedure after being advised of relevant facts and risks?
• In acquiring ACR QA data, Image 211 is used to evaluate for what quality measure?
• Which setting is most directly altered to enhance T2 contrast in a spin-echo image?
• Which artery courses within the Sylvian fissure to supply portions of the cerebral cortex?
• Which metal is ferromagnetic at room temperature?
• Which MRI sequence suppresses fluids by using a long echo time and a long inversion time?
• The Larmor frequency is defined as gamma times the magnetic field.
• In a gradient-echo sequence, which element is not typically used?
• The level-of-concern guidelines tie heating risk to which physiological change?
• Which of the following aspects is regulated by the FDA in MRI safety?
• If a sequence with a matrix of 256 x 512 is adjusted to 512 x 512, the SNR will decrease and the scan time will increase.
• What is the name of the SI unit used to express magnetic field strength?
• Which techniques should be avoided in metal artifact reduction sequences because they require a gradient-echo based coil calibration sequence prior to implementation?
• The minimum acceptable method for detection of intra-ocular ferrous foreign bodies is
• Which body parts require particular caution due to slow heat dissipation from SAR exposure?
• A Free Induction Decay (FID) is produced from a which of the following?
• Which artery travels through the Sylvian fissure as it reaches the lateral aspect of the brain?
• Which statement best describes Proton Density weighting?
• Which change specifically reduces chemical shift artifacts without changing geometry?
• In a dual-echo spin-echo sequence, TE1 is shorter than TE2.
• The RF system frequency used for the first MR image was approximately what?
• Partial or fractional echo describes what phenomenon in k-space data acquisition?
• What is the general term for any deviation in an MR image that does not reflect true tissue characteristics?
• In the Image 73 diagram, which option labels the Slice select gradient?
• Column A in Image 112 corresponds to which MRI pulse sequence?
• In an inversion recovery sequence, image contrast is controlled by:
• For a 1.0 Tesla MR system, the center frequency is approximately which value?
• Presaturation pulses typically occur:
• The measurement of radiofrequency absorption is delineated as which unit?
• Maintaining room temperature, humidity, and airflow in the MR scan room is recommended to reduce which risk?
• The term 'echo train' refers to what in MRI terminology?
• After a 90-degree RF pulse, in which plane is the magnetization primarily oriented?
• Passive shielding in an MR room is typically accomplished by lining the room with which material?
• A coil that is not properly tuned to the correct magnetic field strength will result in:
• Which gradient is used to encode information along the frequency-encoding (readout) axis?
• Which of the following has been documented to cause muscle contractions, cardiac arrhythmias, mild cutaneous sensations and visual light flashes?
• Which term describes the linear change in the magnetic field along a given orientation?
• Tissues with ______ are bright on T1 weighted spin echo scans and tissues with _________ are bright on T2 weighted spin echo scans.
• The intensity limit for a static magnetic field in clinical use is limited by the FDA to:
• Why are fast spin echo sequences fast?
• If the field of view is reduced, what happens to SNR?
• The mathematical process that converts raw MRI data into an image is called:
• If per-slice coverage is 5 mm and there are 24 slices, total coverage is 12 cm. Which option is correct?
• Image 76 depicts which MRI pulse sequence?
• Which slice thickness should be chosen to create an isotropic voxel given TR 2000, TE 90, matrix 256 x 256, and FOV 32 cm?
• Which gradient is used to slice-select the imaging plane in a 2D MRI acquisition?
• Which factor does not contribute to the magnetic force on an object in a static magnetic environment?
• Which artifact is minimized by increasing interslice gap?
• In Image 76, Letter D corresponds to which gradient?
• What safety-related physiological response defines the FDA guidance for time-varying magnetic fields in MRI safety?
• An abbreviation for a Latin word that means nothing by mouth?
• The energy populations at thermal equilibrium cause the net magnetization to align with which direction relative to the main magnetic field?
• In acquiring ACR QA data, Image 212 is used to evaluate which quality measure?
• Which statement best describes the effect of TE on contrast and SNR?
• Which term may be defined as a personal injury or as "a civil action other than a breach of contract"?
• Where is the patient image display with sequence parameter visualization located?
• Which implant would be considered acceptable for an MRI scan at 1.5 Tesla?
• Which artifact mimics a syrinx in the spine?
• Transmit gain is a QA measure evaluating for which of the following?
• As the TE is increased, which statement is true?
• Which MRI sequence is most useful for evaluating demyelinating disease?
• How many radiofrequency pulses produce a FID?
• Increasing diffusion weighting in diffusion weighted imaging is achieved by increasing which parameter?
• Echoes in gradient-echo sequences are formed primarily by what mechanism?
• If the maximum number of slices per TR is 10 and 26 slices are needed for coverage, how many acquisitions (packages) are required?
• Which combination correctly identifies a material and shielding type used to reduce the fringe field in MR rooms?
• What is the echo produced by switching a pair of dephasing and rephasing gradients without a 180° refocusing pulse called?
• Who discovered that moving a magnet inside a coil of copper wire induces an electric current?
• Which mathematical transform is primarily used by the array processor to reconstruct MR images?
• In order to maximize T2 weighting, which parameter would you adjust?
• Echo Planar Imaging is best described as what?
• Which discovery is associated with distinguishing tissue types in MRI using NMR relaxation times?
• Which phenomenon occurs when a ferromagnetic object becomes magnetized in the presence of the MRI's main static field?
• The statement 'RF converts FID into an echo' is:
• Image 82 was acquired at which field strength?
• Field strength at magnet isocenter is measured in units of:
• In STIR sequences, which parameter is adjusted to null fat signal?
• Another name for a picture element is a:
• If a transverse/axial slice plane is selected, which gradient is enabled to alter the magnetic field around the patient's body?
• Image 92 was acquired at what field strength?
• _____________ occurs after initial RF application, causing phase differences to appear between precessing spins, resulting in decay of transverse magnetization.
• Who discovered that a charged particle spinning around its own axis has a magnetic moment?
• If 24 slices of 4 mm thickness are planned with a 1 mm interslice gap, the total anatomic coverage is how many centimeters?
• A proton density weighted image will have a repetition time (TR) in the range of:
• Which parameter is not included in the scan time formula TR × Phase Matrix × NEX ÷ ETL = total ms?
• The fringe magnetic field can cause what effect on nearby medical devices?
• The effects of time varying magnetic fields can include all of the following EXCEPT which one?
• Which tissue is typically hyperintense on T2-weighted imaging?
• The strength of the gradient over a specific distance is known as the:
• Which of the following statements best describes the purpose of shielding in MR environments?
• The artifact in Image 99 is caused by?
• The coil construction in an MR system, from the innermost aspect to the outer, is which sequence?
• As the flip angle is increased, SNR increases up to which point?
• Which agent is used as an anti-peristalsis agent in MR Enterography procedures?
• The distance between echoes is called:
• The artifact described as FID crushing/ fine line is a type of what artifact?
• The duty cycle in MRI sequences is best described as which of the following?
• Which term describes the component of magnetization that remains aligned with the main magnetic field before excitation?
• Which component is responsible for exciting spins in most MRI sequences?
• The net magnetization vector (NMV), when aligned with the magnetic field direction, is aligned __________.
• Which term describes the relative differences in signal intensity between neighboring tissues?
• Which imaging modality offers higher sensitivity for detecting small intra-ocular ferrous foreign bodies?
• What quantity is defined as the ratio of the magnetic moment to angular momentum for a rotating charged particle?
• Applying two gradients simultaneously during slice selection would:
• Increasing NSA will
• Which sequence is best described as fat-suppressed edema detection in musculoskeletal imaging?
• Which statement about surface coils is incorrect?
• Geometric accuracy in ACR QA data is primarily concerned with which feature?
• In SPGR sequence spoiling, what magnetization is spoiled?
• In what anatomical region would you expect to see chemical misregistration the least?
• What term describes the interval between successive echoes in an MRI sequence?
• A pediatric patient undergoing an MRI with conscious sedation should be given nothing by mouth (NPO) for how many hours before sedation?
• Which statement best describes fast spin echo trains?
• FDA guidelines dictate a level of concern when RF energy absorption produces an increase in body temperature of how many degrees Celsius?
• Which quantity is intrinsic to tissue?
• The unit of measurement of the magnetic field surrounding the periphery of the MR scanner is expressed as:
• Which column in Image 109 corresponds to the same sequence as Column B in Image 111?
• To convert total anatomic coverage from millimeters to centimeters, you divide by 10. Which option matches this conversion?
• __________ are caused by local eddy currents due to the increased conductivity of body tissue, and are identified by areas of shading or signal loss.
• Which type of magnet can be shut off the quickest in an emergency?
• Column A in Image 111 corresponds to which MRI pulse sequence?
• Lengthening the repetition time (TR) while using a short echo time (TE) in a spin echo sequence increases which type of weighting?
• Which artery is linked to the Sylvian fissure by its anatomical path?
• Regions of the body that do not rapidly dissipate heat from SAR during MR procedures are the
• Which tort doctrine holds an employer liable for the actions of its employees?
• Fat suppression techniques suppress fat signal based on which property of fat?
• Which law states that a changing magnetic field will induce a voltage?
• Magnetic field inhomogeneity is expressed in
• ADC stands for:
• To maximize T2 weighting while maintaining signal, which combination is most appropriate?
• What term describes any disease-producing agent, such as a virus or bacterium?
• Gradient moment nulling is used to compensate for which motions or flow? I. First order motion II. Second order motion III. Slow flowing vessels IV. Fast flowing vessels.
• What term defines the extent to which a material becomes magnetized in an external magnetic field?
• Which material is used to contain the RF energy in an MR magnet room?
• Image 73 is a diagram of which pulse sequence?
• The process that digitizes the MR signals is known as:
• An array processor in MRI is best described as which of the following?
• Which metal is non-ferrous?
• An isotropic voxel refers to a ______ shaped voxel.
• The fat-water chemical shift difference is approximately which value in ppm?
• If a coronal slice plane is selected, which gradient is enabled to alter the magnetic field around the patient's body?
• Which of the following is short for 3 times/daily?
• A STIR sequence with a TI time of 160 ms will null signal from fat at what field strength?
• Which orientation describes the direction of the magnetic field in Image 79?
• The 1.5T fat-water frequency difference is an example of which MR phenomenon?
• Which component is closest to the patient in the typical MRI coil assembly?
• Raising the receiver bandwidth has what effect on SNR?
• If TR is increased, which statements become true?
• Which MR protocol commonly uses an anti-peristalsis agent to reduce bowel motion?
• CSF suppression is performed with which type of imaging technique?
• Which MRI sequence suppresses CSF signal to better detect white matter lesions?
• To reduce susceptibility artifacts in diffusion-weighted imaging near air-tissue interfaces, which strategy is recommended?
• In a dual-contrast spin-echo sequence with echo times of 25 ms and 90 ms, the second echo image has which characteristics compared to the first?
• Which contrast-enhanced MR technique is used to visualize vessels after gadolinium administration?
• In MR coil configurations, which component is described as the innermost layer?
• An MR sequence that begins with a 180° inversion pulse, followed by a 90° excitation pulse, then a 180° refocusing pulse is known as:
• Active shielding in MRI is defined as which mechanism?
• FDA limits for whole body SAR is ______ over 15 minutes of scanning.
• To produce an image based on differences in T1, the time interval between 90° excitation pulses should be:
• The net magnetization vector aligned with the magnetic field lies along which axis?
• Column A in Image 109 corresponds to which MRI pulse sequence?
• High-field MRI scanners are typically greater than or equal to which field strength?
• Increasing the TE in a spin echo pulse sequence:
• Which statement about T2-weighted sequences is correct?
• Column D in Image 111 corresponds to which MRI pulse sequence?
• In 1975, which scientist introduced 2D NMR using phase and frequency encoding, and the Fourier Transform?
• What conversion factor is used to convert pounds to kilograms in the dosing example?
• Which nucleus corresponds to the gyromagnetic ratio value of approximately 42.57 MHz per Tesla?
• Increasing field strength generally has what effect on chemical shift artifacts?
• In a 3D acquisition with a matrix of 192 x 256, which value represents the phase-encoding steps?
• What condition would lead to poor fat suppression?
• In acquiring ACR QA data, Image 213 is used in evaluating what quality measure?
• Reducing the TE:
• Which scientist is associated with developing the equation for the precession of nuclear spins in a magnetic field?
• Which arteries join together to form the basilar artery?
• Which artifact is caused by local magnetic field distortions due to metal or strong susceptibilities in the imaging region?
• In the context of the Image 73 diagram, which option labels the Radiofrequency (RF) component?
• Lowering the receiver bandwidth increases readout time.
• A sequence with a long TR and a short TE will exhibit PD weighting.
• Normal blood pressure is which of the following values?
• Which of the following is NOT a risk factor for SAR absorption during an MR pulse sequence?
• If the NEX is increased from 2 to 6, the SNR increase would be approximately:
• Which formula represents the 3D scan time?
• SSFP is an abbreviation for:
• Which symptom is most commonly reported as a contrast reaction in MRI procedures?
• When TR is increased, which of the following is true?
• Increasing the field of view (FOV) would have what effect on image quality?
• Which abbreviation means 'twice daily'?
• Which sequence is best suited for edema assessment due to fat suppression?
• VoLumen is primarily used to enhance which anatomical region in MR imaging?
• Which pulse sequence transmits the most RF to the patient and may have more SAR restrictions?
• RBW is an abbreviation for:
• Which abbreviation represents a twice-daily dosing schedule?
• Which pulse sequence parameter combination would yield the image with the most blurring?
• The diastolic component of normal blood pressure, as cited, is which value?
• In gradient echo imaging, which mechanism is used to generate the echo?
• Which gradient encodes phase information perpendicular to the slice plane?
• If a sequence has a TR of about 500 ms and a TE of about 15 ms, what weighting is most likely?
• The phase encoding gradient is used to encode which spatial dimension?
• The Larmor frequency is proportional to which combination of variables?
• Which term refers to a medical or psychological treatment guideline that can be general or specific?
• A sequence with a short TR and a short TE will exhibit which weighting?
• Susceptibility artifacts are more prominent with which MRI sequence type?
• Immediately after a 90-degree RF pulse, the net magnetization:
• Which parameter describes the RF transmit field in MR imaging?
• Which axis gradient corresponds to encoding along the anterior-posterior direction?
• The MRI system that uses liquid cryogens to achieve superconductivity is the:
• The location order of the coils installed in the MRI scanner, from the inner point closest to the patient to the outermost edge, is which sequence?
• Which gradient defines the thickness of the excited slice?
• Who conceived the idea of echo planar imaging, enabling rapid whole-brain scanning?
• The purpose of shimming the magnet is to:
• What is true about the effect of a 90° RF pulse on magnetization components?
• What type of magnet is used with most systems currently manufactured?
• In diffusion weighted imaging, what parameter directly controls the strength of diffusion weighting?
• Removing or killing all microorganisms completely refers to which concept?
• Which sequence type is associated with multiple echo trains and potential tissue heating due to RF exposure?
• The frequency difference between fat and water at 1 Tesla is approximately:
• What term is defined as a volume element with three-dimensional characteristics?
• What is the primary purpose of the maximum intensity projection (MIP) algorithm in MRI?
• Calculate the voxel volume for the following pulse sequence: TR 2000, TE 85, FOV 28 cm, Matrix 272 x 320, 5 mm slice thickness, 3 NSA.
• In inversion recovery, what is the role of the 180° inversion pulse?
• Reducing the field of view (FOV) only will result in which change to the signal-to-noise ratio?
• Using a steep slice select slope and/or narrow bandwidth affects slice thickness by:
• Which pair won the Nobel Prize in 1952 for their invention of equipment which could measure magnetic resonance in solids and fluids?
• What happens when TR is reduced?
• ROI stands for which phrase?
• What term describes a voxel that has uneven measurements with regards to the phase, frequency and slice thickness dimensions?
• If the repetition time is doubled, the scan time will:
• In order to generate an MR image, the slice select gradient must be turned on during:
• Which term describes the containment of the static magnetic field through the use of secondary coils around the MRI scanner?
• The general public is limited to a magnetic field of
• Decreasing the receiver bandwidth increases SNR and lengthens readout time.
• Who discovered the spin echo phenomenon for nuclear magnetic resonance measurements?
• In emergencies, implied consent applies in which scenario?
• Where is the array processor that reconstructs MR images typically located?
• The diagram depicts which MRI pulse sequence?
• To obtain a thin slice thickness, which method is used?
• The liquid cryogens most often used to maintain field strength in a superconducting MR system are:
• TI in inversion recovery stands for which parameter?
• Inversion recovery imaging, which parameter primarily controls tissue contrast by nulling certain tissues?
• Which technique reduces scan time by not filling as many lines of k-space in the phase direction while maintaining spatial resolution?
• Which of the following best defines repetition time (TR)?
• Hydrogen precesses at approximately how many MHz per tesla?
• Which statement best describes T1 recovery?
• The signal reaches its peak at which timing parameter?
• To minimize cross talk artifact in multi-slice imaging, which adjustment should be made?
• Gibbs truncation artifact can be mitigated by increasing which parameter?
• Which statement best describes the effect of using a narrow receiver bandwidth in MRI?
• An intramuscular injection of Glucagon for MR Enterography is an example of a parenteral method of drug delivery.
• In a 3D MRI scan time equation, what does the '# slices' term represent?
• The medical term used to describe vomiting is which of the following?
• Image 77 is a diagram of which pulse sequence?
• ROI stands for which of the following?
• In the event of severe bronchospasms after contrast injection, which medication would likely be administered by the radiologist or nurse?
• DSC refers to:
• A fast spin echo sequence is faster than a conventional spin echo sequence because:
• Column C in Image 112 corresponds to which MRI pulse sequence?
• For a given number of slices, which pulse sequence uses the most 180° RF pulses during each TR period?
• The NSA abbreviation stands for which phrase?
• In T1 weighted images, which tissue tends to appear bright?
• Which term describes the degree of magnetization of an object?
• Which gradient is applied during the moment when the MR echo is formed?
• Which parameter determines the timing between the inversion pulse and data acquisition in inversion recovery imaging?
• Which scientist is credited with discovering that electricity and magnetism are linked by showing that a current in a wire produces a magnetic field?
• What phenomenon causes the chemical shift artifact described for Image 101?
• To reduce chemical shift artifacts, which adjustment should be made?
• Which artery passes beneath the operculum within the Sylvian fissure?
• When performing a gradient echo pulse sequence, what is used to refocus the protons and create the echo?
• In Image 76, Letter B corresponds to which gradient?
• Gradient moment nulling is used to compensate for: I. First order motion II. Second order motion III. Slow flowing vessels IV. Fast flowing vessels.
• FDA safety levels for RF exposure during MR use SAR restrictions to reduce risk of what?
• DCE refers to:
• Which pulse sequence is commonly used to suppress fat while highlighting fluid on T2-weighted images?
• As the TR is increased, which statements are true?
• At 1 Tesla, the frequency difference between fat and water is approximately:
• Which of the following best defines echo time (TE)?
• Which component of the MR system serves as a transceiver coil with broad field of view but typically lower SNR compared with localized coils?
• Metastatic lesions enhance after gadolinium injection due to what mechanism?
• Which corrective measure is suggested for the artifact shown in Image 172?
• Decreasing the receiver bandwidth by a factor of two has what effect on SNR?
• The magnetic field to which MR technologists are most exposed is the:
• If the radiologist requires 3 mm slices axially acquired through the IAC, with a slice gap of 0.5 mm, and requires 4.2 cm total coverage, how many slices must be selected?
• Which MRI pulse sequence provides proton density contrast?
• Motion appears as smearing along which encoding direction in MRI?
• Which term describes a voxel with nonuniform dimensions along the three spatial axes?
• The array processor is responsible for:
• What instrument allows a patient to appoint an agent to make health care decisions if the patient is unable to do so?
• In 3D volume imaging, the overall SNR will increase when there is an increase in either the Field of View (FOV) and/or the number of slices or partitions (chunks). Which option best describes this relationship?
• Which sequence uses the most 180° RF pulses during each TR period?
• Tid stands for which of the following?
• The liquid cryogens are cooled in a superconducting MRI magnet at what temperature (in Kelvin)?
• If you increase the flip angle toward the Ernst angle, what happens to SNR?
• Calculate the pixel area for the following sequence: TR 4000, TE 120, FOV 28 cm, 304 x 304 matrix, 2 NEX, ETL 12.
• Which term describes the effect of introducing a substance with negative magnetic susceptibility that slightly weakens the magnetic field?
• A proton density weighted image will have an echo time (TE) in the range of:
• Which material is commonly used for RF shielding in MR rooms?
• Which intracranial artery passes through the Sylvian fissure?
• According to the FDA, a severe reaction to MR contrast would be described as which of the following?
• Increasing TR generally has which effect on T1 contrast?
• Hydrogen protons in the anti-parallel state are described as which of the following?
• To correct the artifact in Image 85, which parameter should be increased?
• Narrowing the receiver bandwidth decreases the number of slices available.
• Which artery is commonly described as running inside the lateral sulcus?
• In MR safety, SAR restrictions are primarily intended to prevent what type of injury?
• Letter D in Image 73 represents which component?
• Which modality is typically used first to screen for intra-ocular ferrous foreign bodies?
• In a 1.5 Tesla MRI, the inversion time TI for a T2 STIR sequence is typically in which range?
• Which RF pulse is always absent in a gradient echo sequence?
• What combination of TR and TE characterizes a T2-weighted sequence?
• Which parameter combination would yield the most T1 weighting?
• What is the primary function of the 180-degree refocusing RF pulse in a spin-echo sequence?
• In a fast spin echo pulse sequence, if the TSE factor (echo train length) is increased by a factor of 3, the scan time will be:
• In MRI hardware, which component is responsible for converting the received MR signal into a digital representation?
• Hydrogen is used in MR imaging because of:
• Which artery is the primary course along the Sylvian fissure?
• An MR signal generated by an RF or a gradient pulse is called a(n):
• In a cross-sectional view of MR magnet design, which coils are closest to the patient?
• The difference in chemical shift is approximately ______ parts-per-million
• The Magnevist MRI contrast agent is based on which element?
• Hydrogen gyromagnetic ratio in frequency units per Tesla is approximately:
• Which column in Image 111 corresponds to the same sequence as Column A in Image 109?
• Which sequence is most insensitive to magnetic field inhomogeneity?
• Which pair won the 2003 Nobel Prize in Medicine for their work in MR imaging techniques and capabilities in the 1970s?
• For a T2 weighted, fast spin echo image with TR 1.1 s and TE 90 ms, what's wrong?
• Which statement best describes the role of the 90º RF excitation pulse in the sequence described?
• The range of transmitted frequencies at each slice position must _____ to maintain slice thickness.
• A 6 inch surface coil is able to receive signal:
• The Larmor equation relates precession frequency to magnetic field as:
• RF shielding can be achieved by lining the scanner room walls with which material?
• NEX stands for which of the following?
• The scan time for a fast spin echo sequence with TR 3500 ms, TE 90 ms, 256x256 matrix, NSA 1, FOV 220 mm, and ETL 5 is approximately how many minutes?
• Which parameter, when increased, is most likely to improve the signal-to-noise ratio (SNR)?
• To correct the artifact shown, the MRI technologist would:
• Which organization regulates the maximum clinically allowed static magnetic field strength?
• A sign that a patient may be in cardiac arrest is Not having a pulse. Which of the following is most consistent with this sign?
• What is the effect of using a narrow receiver bandwidth in MRI?
• Which technique compensates for motion due to heartbeats and pulsatile flow by synchronizing acquisition with movement?
• The pituitary stalk is also known as which structure?
• Column C in Image 109 corresponds to which MRI pulse sequence?
• What is the term used to measure the magnetic field strength in the periphery of the MRI scan room?
• NEX stands for which term?
• Artifacts primarily arising from active RF coil channels or elements outside the scanning field of view can be corrected by de-selecting which elements?
• What metric is used to quantify RF energy absorption in tissue during MRI safety guidelines?
• What term describes the components of the magnetization in the imaging object after excitation that are sampled from the receiver coil and stored as a function of time during data acquisition?
• Fat generally has which combination of T1 and T2 relaxation times?
• The precessional frequency of hydrogen at 3 Tesla is approximately:**
• When moving blood enters a magnetic field and alters the ECG, producing a T-wave change described as swelling or a spike, this is called the
• What term refers to the RF transmit field generated within the transceiver coil?
• Which statement best defines echo time (TE) in MRI?
• Which arterial pathway is associated with the Sylvian fissure in neuroanatomy?
• Which contrast agent is used intravenously to enhance CNS imaging?
• In sagittal cervical spine MRI, CSF flow artifacts can be mitigated by which technique?
• Who discovered that tumors and normal tissue can be distinguished by NMR because of their relaxation times?
• In an inversion recovery sequence, the time interval between the 180° RF pulse and the 90° RF pulse is the:
• Water is hyperintense and fat is typically dark in:
• In 3D MRI, increasing Field of View (FOV) has what effect on SNR?
• The units used to express gradient strength include Gauss per centimeter and Millitesla per meter; these are examples of what measurement?
• VoLumen would be selected for which MR procedure?
• An example of a parenteral drug delivery method is:
• Which weighting uses a long echo time (TE) to emphasize differences in T2 relaxation?
• Column C in Image 111 corresponds to which MRI pulse sequence?
• In a sagittal cervical spine MRI, what could be done to compensate for CSF flow artifacts?
• Which statement about repetition time is true?
• Which is TRUE regarding spin echo sequences?
• The angle to which the longitudinal magnetization is tipped into the transverse plane after the initial RF excitation is called the:
• In k-space, which lines primarily contain high-resolution data?
• Increasing ETL (echo train length) while keeping TR, Phase Matrix, and NEX constant will have what effect on scan time?
• T1 weighting is adjusted with short TE's?
• A pulse sequence that begins with a 180° RF pulse, followed by a 90° RF excitation pulse, would be a(n):
• The gradient rise time is defined as the
• A T2 weighted gradient echo image is obtained with which parameter combination?
• Which cryogen is used to maintain superconductivity in MR systems?
• The orientation of the main magnetic field in a high field, superconducting, short bore magnet is:
• Which technique can eliminate FID crushing artifacts?
• The relaxation process associated with recovery of magnetization along the main field is called:
• RF heating is more of a concern in ________ sequences.
• What term refers to signal misrepresentations that do not correspond to the spatial location of the tissue imaged?
• What is defined as a picture element and has two-dimensional characteristics?
• Potential risk factors for SAR thermal absorption during an MR pulse sequence EXCEPT:
• Which statement best describes the relationship between magnetic field strength and SNR in MR imaging?
• In a typical MR coil assembly, which element is outermost?
• LPM stands for which term in measurements?
• Which TR and TE combination would most likely show edema as hyperintense?
• A Proton Density weighted image is characterized by which combination of TR and TE?
• Presaturation pulses are often used to
• In a Fast Spin Echo sequence, the TSE factor is synonymous with which term?
• Which statement correctly describes the commonality of MRI contrast reactions?
• Which display mode presents the sequence of images to resemble motion such as CSF flow or cardiac movement over time?
• The Sylvian fissure is traversed by which major cerebral artery?
• Which has a higher precessional frequency?
• The yellow arrows indicate what type of MRI artifact?
• Which method reduces MRI scan time by not filling as many lines of k-space in the phase direction while maintaining spatial resolution?
• In an inversion recovery sequence, which RF pulse inverts the longitudinal magnetization?
• What unit is used to measure the magnetic field strength at the edge of the MRI environment?
• In a multi-channel MR receive system, which term describes the combination of multiple coil elements?
• Compared to water, fat generally has what combination of T1 and T2 relaxation times?
• Which images are reconstructed from diffusion weighted images with multiple b-values and correspond to the spatially distributed diffusion coefficients of the tissues?
• Which artifact results from averaging signal across tissues within a thick slice?
• Which MR technique generates a spectrum of metabolites in a specific volume of interest?
• Immediately after a 90° RF pulse, the transverse magnetization is which of the following?
• Calculate the voxel volume for the following pulse sequence: TR 450, TE 20, FOV 24 cm, 320 x 320 matrix, 3 mm slice thickness.
• The RF energy transmitted to produce a slice at 0.995 T would be approximately how many MHz?
• The time between the excitation pulse and the resulting echo is known as:
• Which quantity is defined as the Z component of the net magnetization vector in the direction of the static magnetic field?
• Which of the following statements is true about passive shielding for MRI rooms?
• Which gradient encodes spatial information along the readout axis?
• Which statement about water relaxation times is true?
• Column B in Image 109 corresponds to which MRI pulse sequence?
• Which factors influence the force on an object in a magnetic environment?
• Which statement about the use of surface coils is NOT correct?
• Reducing the slice thickness will result in which change to SNR?
• Calculate the dose for a patient weighing 176 pounds with a 0.2 mL/kg protocol (answer given is 16 mL). What is the correct total volume?
• In MR shielding discussions, which material is associated with RF energy containment?
• In diffusion-weighted imaging, susceptibility artifacts near air-tissue interfaces can be reduced by increasing which parameter?
• The fastest sequence commonly and currently available is:
• Which term describes the phase encoding step in MRI data acquisition?
• Reducing the number of lines filled in k-space will produce an image:
• In Image 76, Letter G represents which element?
• The magnetic and thermal environment through which nuclei exchange energy in longitudinal relaxation is called:
• A 180-degree RF pulse is most characteristic of which sequence?
• Gradient echo sequences use flip angles for which purpose?
• Functional MRI (fMRI) was developed in which year?
• What is the term used to describe the adjustment of the current within the shim coils on a per patient or per sequence basis?
• At 1.5 Tesla, the chemical shift between fat and water is which value in Hz?
• Which of the following best describes the relationship between RF energy and tissue heating in MRI safety?
• Which parameter change is most likely to increase image blur in a fast spin-echo sequence?
• NPO is an abbreviation used to denote what?
• In MRI, what is the function of gadolinium?
• Which gradient is used to encode the frequency-encoded (readout) axis?
• Which term refers to professional negligence by a health care provider that falls below the accepted standard and causes injury or death?
• RF energy in MRI is best described as what type of radiation?
• Letter B in Image 73 represents which component?
• As the flip angle is doubled, RF absorption increases by a factor of
• The FDA limit on time-varying magnetic fields is determined by the onset of which physiological response?
• The lateral sulcus is traversed by which intracranial artery?
• In 3D volume imaging, increasing FOV or increasing the number of slices increases SNR. Which statement best describes this relationship?
• An increase in repetition time (TR) will produce all of the following EXCEPT:
• In MRI, energy transfer between a transmitter and receiver requires the two to be at the same:
• Which combination of TR and TE best produces proton density weighting?
• Which weighting is typically used to depict pathology?
• Which data unit represents a three-dimensional portion of the image volume?
• Which fundamental property relates a nucleus's magnetic moment to its angular momentum?
• To ensure efficient energy transfer in an MRI system, transmitter and receiver must share the same:
• What term describes the failure to exercise the care that a reasonably prudent person would exercise?
• Who developed the mathematical equation to analyze the heat transfer between solid bodies, later becoming the basis for rapid processing of MRI phase and frequency signals?
• Which of the following is a safe unit for expressing FDA's whole-body SAR limit?
• In a gradient echo sequence, reducing the flip angle while maintaining the TR reduces:
• Presaturation pulses are commonly used to reduce which type of artifact?
• The arrows in Image 85 indicate which kind of artifact?
• The smallest resolvable object for an image with a 20 cm FOV and a 224 x 224 matrix is approximately how many millimeters?
• Which change would increase voxel volume?
• What does NEX stand for in MRI terminology?
• Complete saturation is defined as which condition?
• Which sequence is T2 weighted with fat suppression?
• Which phenomenon arises after RF excitation as spins precess at different rates, leading to a decay of transverse magnetization?
• In Image 76, Letter F corresponds to which timing parameter?
• A reduction in field of view (FOV) will result in which change to SNR?
• Column D in Image 109 corresponds to which MRI pulse sequence?
• Dielectric effects in MRI are caused by what mechanism?
• The technique that times MR data collection to physiological motion to minimize motion artifacts is known as:
• The duty cycle is defined as the
• Where is the local RF coil used to image a human brain typically located?
• Which adjustment would NOT increase signal-to-noise ratio?
• Narrowing the receiver bandwidth increases susceptibility artifacts.
• The primary biological effect of radiofrequency fields in MRI is
• Which echo type is produced without using a 180-degree refocusing pulse?
• Which gradient defines each line of k-space?
• NMV is short for:
• Which artery passes through the Sylvian fissure to vascularize the lateral brain surface?
• What is the term for the resonance frequency of a nucleus that scales directly with magnetic field strength?
• In terms of anatomy, which artery runs along the lateral cerebral sulcus known as the Sylvian fissure?
• A sequence with a long TR and a long TE will exhibit T2 weighting.
• After administering IV gadolinium contrast, what is recommended?
• Which expression correctly computes the scan time for a fast spin echo sequence given TR, Phase Matrix, NEX, and ETL?
• Which phenomenon involves a visual sensation described as seeing stars during MR procedures?
• In Short TI Inversion Recovery, the inversion time is set to approximately what fraction of the T1 of fat to null fat signal?
• A Free Induction Decay (FID) is characterized by which type of signal?
• The stage of disease with no symptoms is the:
• Which route would be considered enteral?
• What is the name of the technique that acquires slightly more than half of the phase-encoding samples and fills the remainder with zeros?
• Which factors affect the flip angle in MRI?
• In a dual-echo spin-echo sequence, TE1 refers to which parameter?
• What is defined as the excess number of hydrogen protons aligned with the static magnetic field direction (B0)?
• The quantity defined as the number of times a periodic function or vibration repeats itself in a specified time, usually measured in hertz, is:
• When the TE is lowered, what happens to susceptibility artifact?
• When going from a linear coil to a quadrature coil:
• Which artifact is most likely seen as motion or ghosting in the phase-encoding direction?
• The __________ magnetic field poses risks to patients and staff due to the torpedo effect when a ferromagnetic object becomes magnetized and attracts to the large magnet.
• Which parameter defines the time from the RF excitation pulse to the detected echo?
• Tau (1/2 TE) represents what timing concept?
• TE stands for Time to Echo.
• Who detected and measured single states of rotation of atoms and molecules in the 1930s, determining the magnetic moments of nuclei?
• For a protocol of 0.1 mmol/kg, what is the mmol dose for an 80 kg patient?
• Which MRI sequence is a fat-suppressed, inversion-recovery technique?
• If hydrogen precesses at about 42.57 MHz per tesla, what is the approximate precession frequency at 2 Tesla?
• Which term is defined as a civil action for personal injury not arising from contract?
• A system operating at 30,000 Gauss has a field strength of approximately how many Tesla?
• To convert a scan time computed in milliseconds to seconds, which operation should be performed?
• Low-contrast spatial resolution QA assesses the system's ability to differentiate objects with similar intensities.
• The analog-to-digital converter (ADC) is a component of the computer system responsible for what function?
• T1 recovery refers to:
• The chemical shift artifact occurs because fat and water precess at different frequencies. Which option best describes this phenomenon?
• Sedated patients must always be monitored with which device?
• Which sequence is purely proton density imaging with no suppression?