MRI Physics and Clinical Applications Practice Exam

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• Which of the following is commonly considered an intrinsic MR contrast mechanism?
• In a strong magnetic field, the net magnetization of protons tends to align with the external field along which axis?
• A receive-only coil is primarily used to do what?
• What is the greatest risk associated with an uncontrolled magnet quench?
• The application of an RF pulse causing resonance to occur is known as?
• Which is NOT considered intrinsic MR contrast?
• The complete elimination of all pathogens and microorganisms is referred to as which term?
• Which would cause a phase mismapping artifact?
• As phase encoding steps increase, spatial resolution increases due to?
• What is the best strategy for reducing chemical shift artifacts?
• Which is the primary MR signal resulting from a 90 degree excitation RF pulse?
• Which contrast agent is most commonly used in MRI?
• Compared to iodinated CT contrast, gadolinium adverse reactions are?
• Increasing phase encoding steps changes voxel size by causing voxels to?
• Cardiac CINE MRI relies primarily on high:
• The 180-90-180 pulse sequence is most commonly associated with which pulse sequence type?
• When using a receive-only or phased-array coil, which transmits the RF pulse?
• Increasing slice thickness generally leads to what change in SNR?
• Which three parameters control voxel size and image spatial resolution?
• Which pulse sequence is NOT typically used in MR Neurography?
• Which pillow handling measure aligns with reducing infection risk for pillows in the MRI suite?
• Which statement about NEX and scan time is true?
• Which patient may be left unattended during an MRI procedure according to standard safety guidelines?
• If voxel size decreases, spatial resolution
• Protocol for allowing a family member to accompany a patient into the scan room?
• Which ETL would theoretically produce the shortest scan time?
• The plane perpendicular to the main magnetic field is called the
• Increasing slice thickness by 50% has what effect on SNR?
• The direction perpendicular to the main magnetic field is designated as?
• Zipper artifact is caused by which environmental condition during acquisition?
• What is another name for phase mismapping artifact?
• Which parameter would NOT increase SNR?
• Which zone is associated with the projectile effect in MRI safety zoning?
• What is the primary role of an MR safety officer when a patient has a questionable implant?
• Increased TE has what direct effect on total scan time?
• An extension of breast tissue into the axilla is known as which term?
• In the event of a suspected anaphylactic reaction to gadolinium-based contrast, what should be the first-line treatment?
• MR Neurography fat suppression sequence: Which sequence is commonly used?
• What is the role of an MR MD when implants are questionable?
• T2* contrast arises from the combination of T2 decay and which additional effect?
• Which parameter has a direct effect on scan time?
• Hazards of cryogens in the MRI environment do NOT include?
• FDA guidelines indicate gadolinium should be avoided when GFR is less than what value?
• Voxel size is determined by which combination of parameters?
• What happens to T1 recovery times of tissues as magnetic field strength increases?
• If the field of view increases and other imaging parameters remain the same, what happens to the pixel size?
• Which combination would likely yield the highest SNR?
• Motion artifacts are identified by which feature?
• SAR measures the delivery of which to the body during an MRI exam?
• What is the primary role of shim coils in MRI?
• Decreasing field of view increases spatial resolution but decreases which of the following?
• Which MRI area is considered a general public area?
• Which constant relates Larmor frequency to magnetic field strength?
• Which coil would yield the smallest transmit RF field?
• Which parameter will influence T1 contrast in a GRE pulse sequence?
• The projectile effect is witnessed in which zone?
• Which is NOT a short-term effect caused by gadolinium contrast injections?
• Which course of action is best when scanning an anxious claustrophobic patient?
• In k-space, the phase encoding direction is?
• T1 relaxation time is best described as recovery of?
• What is the formula for calculating scan time in a basic spin echo pulse sequence?
• The immediate decay of an RF signal in the transverse plane after excitation is referred to as?
• What is the magnetic field created by the nuclear alignment of hydrogen called?
• Decreasing the matrix from 512x512 to 320x320 yields what effect?
• The center of k-space corresponds to which gradient amplitude?
• RF-induced echo signals (spin echo) correct for which type of decay?
• Aliasing artifacts are caused by?
• In a 3D pulse sequence, slice encoding is accomplished by what method?
• For the human eye to detect an increase in SNR, minimum increase required?
• In a fast spin echo sequence, the series of echoes is produced by what kind of pulses?
• Image reconstruction in MRI is accomplished through which mathematical process?
• When should patients with an ICD be scanned?
• If energy is applied at a frequency higher than the precise resonance frequency, what is the expected outcome?
• Which is NOT an advantage of permanent magnets?
• According to the ACR, which class of gadolinium-based contrast agents does NOT require obtaining a patient's eGFR?
• SNR is proportional to voxel volume. If you want to increase SNR by adjusting only one parameter, which change increases voxel volume?
• In a spin echo pulse sequence, which eliminates T2 effects by rephasing transverse magnetization?
• What happens to the precessional frequency when the magnetic field strength increases?
• Which relaxation time is associated with the decay of transverse magnetization due to dephasing?
• Which parameter is primarily responsible for diffusion sensitivity in diffusion-weighted imaging?
• Which laboratory value is essential to assess renal function before gadolinium administration?
• As slice thickness increases, spatial resolution decreases due to corresponding increases of what?
• Which unit is used to express gradient amplitude?
• In the Larmor equation, what does w0 represent?
• In the event of a magnet quench, which environmental effect is most concerning?
• What must be confirmed before scanning a patient with an ICD?
• To increase spatial resolution without affecting scan time, an MRI tech can do?
• Which MRI parameter, when increased, does NOT increase SAR according to common guidance?
• Which artifact is most common in MRI?
• Which condition is necessary for energy to be most efficiently transferred from one system to another?
• Which parameter combination provides the highest SNR (all else equal)?
• How is the homogeneity of the main magnetic field quantified?
• FDA maximum SAR limits?
• Longitudinal magnetization occurs when protons align with which direction of the magnetic field?
• Increasing TR results in which effect on scan time?
• Which protocols would be included in an emergency plan for an outpatient MRI facility?
• Doubling the NSA/NEX results in what percentage increase of SNR?
• Which area does NOT require a screening form to gain access?
• Slice excitation pulses that excite protons in an adjacent slice causing artifactual contrast changes are known as?
• Higher ETL in a fast spin-echo sequence primarily affects which attribute?
• A nucleus with a net spin is described as having which property?
• What blood test results are necessary prior to administering contrast?
• In the scan time formula, which term represents the phase encoding component?
• Which has the longest T1 relaxation time?
• Shim coils are best characterized by?
• The primary objective of the MRI receiver system is to convert analog signals into?
• Which type of magnet can produce field strength greater than 3T?
• In an inversion recovery pulse sequence, the initial excitation pulse drives longitudinal magnetization from +Z to which orientation?
• As voxel size decreases, how is image quality affected?
• Phase encoding in a 2D spin echo is performed after the first slice excitation pulse and before which component?
• What does a moving magnetic field induce in a conductor?
• For unresponsive patients, screening is performed in consultation with?
• As TE increases, which statement best describes T2 contrast?
• Which best describes temporal resolution?
• Which best describes T2 relaxation time?
• As magnetic field strength increases, what happens to T1 relaxation time?
• Perfusion is best described as flow through which type of vessel?
• In an emergency, who is responsible for deciding who enters the magnet room?
• What is the effect on SNR when reducing receiver bandwidth?
• In MRI, which mathematical process converts a dataset in the spatial frequency domain into an image?
• Motion artifacts appear in which direction?
• Which coil provides the most uniform transmit field for body imaging?
• Which characteristic determines if an atom is suitable for use in MRI?
• Which statement best describes the purpose of categorizing gadolinium-based contrast agents into groups by the ACR?
• Gadolinium-based contrast agents primarily shorten T1 relaxation time, resulting in increased signal on which type of images?
• Gloves and gowns should be worn by MRI staff if a patient presents which condition?
• Per FDA guidance, peripheral nerve stimulation is categorized as what type of concern?
• In an emergency, an MRI technologist should take which action?
• Which of the following is NOT a short-term effect of gadolinium injection?
• The center of k-space corresponds to gradient amplitude value of zero. Which option accurately states this gradient amplitude?
• Per the FDA, gadolinium should be avoided for patients with a GFR of?
• Among the following, which field strength is presented as most suitable for high-resolution MR Neurography?
• In the MRI environment, which factor poses the greatest risk for spreading infectious disease?
• Large voxels produce higher SNR than small voxels due to?
• Which hardware is responsible for correcting B0 inhomogeneities?
• During an MRI, what monitoring approach is essential to ensure patient safety by detecting difficulty in real time?
• For imaging a small region like the knee with high SNR, which coil configuration is commonly used?
• A phased array surface coil utilizes several individual coils, each connected directly to a dedicated?
• Which action completes MRI safety protocol for implanted devices?
• One tesla is equal to how many gauss?
• What is the approximate precessional frequency of hydrogen in a 3.0T magnet?
• Which statement is true about gadolinium-based contrast agents?
• MRCP is utilized for which anatomical areas?
• The Larmor equation is:
• What happens to SNR if FOV is decreased?
• Which gradient is responsible for encoding spatial information along the phase-encoding direction in k-space?
• In the context of questionable implants, who has the final decision-making authority regarding MRI eligibility?
• A patient develops hives after gadolinium administration. Which medication should be used?
• Which factor determines the number of lines in k-space that must be filled with data?
• Materials with which component have the highest degree of magnetic susceptibility?
• In safety screening, what is the essential action before MRI entry?
• Why does a 3.0T magnet have inherently higher SNR than 1.5T?
• Below critical temperature, superconducting magnet coils exhibit what type of resistance?
• Which is a unit of measurement for peak amplitude of a gradient magnetic field?
• Increasing slice thickness increases SNR by which method?
• Which symbol represents the oscillating magnetic field (RF)?
• Which imaging technique uses accelerated k-space filling to decrease scan time?
• Anaphylaxis refers to?
• In a 2D spin echo pulse sequence, when does phase encoding occur?
• When placed in a strong magnetic field, protons of a water molecule will align in which direction?
• Motion artifacts can be identified by?
• Which technique is commonly used to minimize motion in cardiac MRI?
• Per the ACR, a pregnant patient may safely undergo MRI at which stage of gestation?
• In MRI, which gradient is used for phase encoding?
• Conductive copper windings that alter the main magnetic field along a strict coordinate are known as?
• What is the cryogen in a superconducting magnet?
• Which component in a spin echo sequence rephases transverse magnetization to form an echo?
• Which artifact results from excitations in adjacent slices due to imperfect slice selection?
• In which order would the following gradients be switched on and off for a standard pulse sequence?
• Which term describes the process that completely destroys all microorganisms, including spores?
• Which is NOT an advantage of superconducting magnets?
• What magnet type is used to achieve field strengths above 3T in clinical MRI?
• In MRI, spatial resolution is defined by?
• In MRI facility zoning, which zone corresponds to general public access?
• What energy does SAR measure as being deposited in tissue?
• Increasing NEX/NSA yields which effects?
• Gadolinium-based contrast agents are primarily used for?
• Which statement best reflects the MRI safety monitoring emphasis on communication?
• What is the time constant of the precessional frequency at 1 Tesla in units of MHz/T?
• What field strength is recommended for MR Neurography according to the source?
• Which is the highest field strength among those listed that is included as a potential option for MR systems in the material?
• To form a chelate, a gadolinium ion is chemically bonded with?
• What effect does increasing TR have on SNR?
• In MRI, which type of material has the highest magnetic susceptibility?
• Which condition puts a patient at greatest risk for developing NSF?
• Perfusion refers to the rate of blood flow through which component of the vascular system?
• Increasing receiver bandwidth reduces which type of artifact?
• The direction of the main magnetic field is designated as?
• Per CDC, what is the leading cause of hospital-acquired infections?
• Which imaging application requires knowledge of temporal resolution?
• The primary route of administration of gadolinium is?
• Which statement best describes the overarching goal of infection control measures in MRI facilities?
• Selecting a larger coil for use on a smaller FOV will increase sensitivity to?
• In an axial MR image, which gradient is responsible for slice encoding?
• In diffusion-weighted imaging, which parameter is primarily responsible for diffusion weighting, differentiating tissues?
• Which condition is necessary for resonance to occur?
• Which causes thermal injuries in the MRI suite?
• A patient indicates having a metallic implant — what are the necessary next steps?
• In MRI safety, SAR units are expressed as?
• What is most likely to cause zipper artifacts?
• Why is administering gadolinium to a pregnant patient considered high risk?
• In a permanent magnet design, the direction of the main magnetic field is?
• Which is an advantage of permanent magnets?
• Inversion recovery orientation after inversion pulse?
• Which is a known adverse reaction (not a side effect) of gadolinium?
• Which artifact results from VENC in phase contrast MRA being lower than the velocity of flow?
• Before administering gadolinium-based contrast in a patient with unknown renal function, what should be checked?
• In diffusion-weighted imaging, which parameter is adjusted to set diffusion weighting?
• Cross excitation artifact arises when slice excitation pulses excite protons in an adjacent slice.
• Which type uses several small surface coils linked together for improved SNR and larger coverage?
• In MRI terminology, what does NMV stand for?
• Which nucleus is most commonly used in MRI to generate a net magnetization in the human body?
• An increase of which does NOT increase SAR?
• What is the correct gadolinium dose for a patient weighing 100 lbs?
• Which statement about phase encoding steps and SNR is true?
• To reduce infection risk in the magnet room, a pillow should be equipped with which feature?
• In a fast (turbo) spin echo pulse sequence, the initial slice excitation pulse is followed by a series of?
• Reducing FOV with a fixed matrix results in what change to SNR?
• Patient screening forms must be completed before a patient enters which zone?
• Which concept best describes why energy transfer is most efficient only when the driving frequency matches the system's natural frequency?
• What is the primary route of administration for gadolinium in MRI?
• Compared to iodinated CT contrast, gadolinium's risk of immediate adverse reactions is?
• Perfusion is most closely associated with flow through which part of the circulatory system?
• The primary advantage of a phased array coil — provides coverage of a larger coil and which characteristic of a smaller coil?
• In a spin echo pulse sequence, the 180 degree RF refocusing pulse produces a signal echo and?
• T2* (T2 star) contrast is a combination of T2 contrast and?
• Free Induction Decay (FID) is defined as?
• Which anatomical term describes the extension of breast tissue into the armpit area?
• Which best describes gradient slew rate?
• When does patient screening begin?
• The use of a phased-array coil in clinical practice is mainly to improve what aspect across a larger region?
• IV contrast agents use which type of ion as the primary contrast mechanism?
• When evaluating a questionable implant for MRI, the MR safety officer's ultimate responsibility is to
• Superconducting magnet coils exhibit what type of resistance at or below critical temperature?
• Which component provides spatial encoding by varying the magnetic field with position?
• Which method reduces cardiac motion artifacts in MRI?
• Which field strength has the highest inherent SNR?
• Which sequence provides high-resolution three-dimensional imaging suitable for visualizing nerve pathways in MR Neurography?