MRI Artifacts and Troubleshooting
Exam Questions with Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which artifact occurs when anatomy outside the selected field of view is
incorrectly displayed within the image?
A. Chemical-shift artifact
B. Susceptibility artifact
C. Wrap-around artifact
D. Zipper artifact
Answer: C. Wrap-around artifact
Wrap-around, or aliasing, occurs when the anatomy extends beyond the sampled
field of view. The unwanted anatomy is mapped into the image, typically along
the phase-encoding direction.
2. In a conventional MRI acquisition, in which direction does wrap-around most
commonly occur?
A. Slice-select direction
B. Phase-encoding direction
C. Frequency-encoding direction
D. Gradient-coil direction
Answer: B. Phase-encoding direction
Aliasing most commonly occurs in the phase-encoding direction because spatial
information in this direction is encoded through discrete phase steps. Increasing
the phase field of view or using phase oversampling can help reduce the artifact.
,3. Which adjustment can reduce phase-direction wrap-around without changing
the anatomy being scanned?
A. Decrease the phase field of view
B. Increase echo time
C. Increase the phase field of view
D. Decrease the number of phase-encoding steps
Answer: C. Increase the phase field of view
Increasing the phase field of view provides greater spatial coverage and reduces
the likelihood that anatomy outside the prescribed area will be mapped into the
image.
4. A repeated image of a patient's motion appears at regular intervals along the
phase-encoding direction. Which artifact is most likely present?
A. Chemical shift
B. Motion ghosting
C. Gibbs ringing
D. Dielectric shading
Answer: B. Motion ghosting
Periodic motion can introduce phase inconsistencies between acquisitions. These
inconsistencies produce repeated displaced signals, or ghosts, commonly along the
phase-encoding direction.
5. Which patient action is most likely to produce respiratory ghosting during an
upper-abdominal MRI?
A. Remaining still
B. Holding the breath as instructed
C. Irregular respiratory motion during acquisition
D. Wearing hearing protection
Answer: C. Irregular respiratory motion during acquisition
,Respiratory motion changes the position and phase of abdominal structures
during acquisition. The resulting inconsistencies can create ghosting and blurring.
6. Which technique can reduce respiratory motion artifacts during abdominal
MRI?
A. Increasing patient movement
B. Respiratory gating or breath-hold imaging
C. Increasing slice thickness in every sequence
D. Removing phase encoding
Answer: B. Respiratory gating or breath-hold imaging
Respiratory gating coordinates acquisition with a selected portion of the breathing
cycle, while breath-hold techniques acquire data during a period of reduced
respiratory motion.
7. Which artifact appears as alternating bright and dark lines near a sharp tissue
boundary?
A. Zipper artifact
B. Gibbs artifact
C. Wrap-around artifact
D. RF interference artifact
Answer: B. Gibbs artifact
Gibbs, or truncation, artifact results from incomplete sampling of high spatial
frequencies. It commonly appears as ringing near high-contrast interfaces.
8. Which change can reduce Gibbs artifact?
A. Reduce the acquisition matrix
B. Increase voxel size
C. Increase spatial sampling
D. Increase patient motion
, Answer: C. Increase spatial sampling
Increasing the matrix or otherwise acquiring additional high-spatial-frequency
information can reduce truncation effects and make Gibbs ringing less prominent.
9. What is the primary cause of chemical-shift artifact between fat and water?
A. Patient motion
B. Gradient failure
C. Different resonance frequencies of fat and water
D. Inadequate slice thickness
Answer: C. Different resonance frequencies of fat and water
Fat and water resonate at slightly different frequencies in a magnetic field. Their
frequency difference can cause spatial misregistration along the frequency-
encoding direction.
10. Which adjustment generally decreases the amount of chemical-shift
displacement?
A. Decrease receiver bandwidth
B. Increase TE only
C. Increase slice thickness
D. Increase receiver bandwidth
Answer: D. Increase receiver bandwidth
Increasing receiver bandwidth reduces the amount of spatial displacement
associated with the frequency difference between fat and water.
11. Which artifact is particularly pronounced around metallic implants?
A. Gibbs artifact
B. Susceptibility artifact
C. Respiratory artifact
D. Wrap-around artifact
Exam Questions with Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which artifact occurs when anatomy outside the selected field of view is
incorrectly displayed within the image?
A. Chemical-shift artifact
B. Susceptibility artifact
C. Wrap-around artifact
D. Zipper artifact
Answer: C. Wrap-around artifact
Wrap-around, or aliasing, occurs when the anatomy extends beyond the sampled
field of view. The unwanted anatomy is mapped into the image, typically along
the phase-encoding direction.
2. In a conventional MRI acquisition, in which direction does wrap-around most
commonly occur?
A. Slice-select direction
B. Phase-encoding direction
C. Frequency-encoding direction
D. Gradient-coil direction
Answer: B. Phase-encoding direction
Aliasing most commonly occurs in the phase-encoding direction because spatial
information in this direction is encoded through discrete phase steps. Increasing
the phase field of view or using phase oversampling can help reduce the artifact.
,3. Which adjustment can reduce phase-direction wrap-around without changing
the anatomy being scanned?
A. Decrease the phase field of view
B. Increase echo time
C. Increase the phase field of view
D. Decrease the number of phase-encoding steps
Answer: C. Increase the phase field of view
Increasing the phase field of view provides greater spatial coverage and reduces
the likelihood that anatomy outside the prescribed area will be mapped into the
image.
4. A repeated image of a patient's motion appears at regular intervals along the
phase-encoding direction. Which artifact is most likely present?
A. Chemical shift
B. Motion ghosting
C. Gibbs ringing
D. Dielectric shading
Answer: B. Motion ghosting
Periodic motion can introduce phase inconsistencies between acquisitions. These
inconsistencies produce repeated displaced signals, or ghosts, commonly along the
phase-encoding direction.
5. Which patient action is most likely to produce respiratory ghosting during an
upper-abdominal MRI?
A. Remaining still
B. Holding the breath as instructed
C. Irregular respiratory motion during acquisition
D. Wearing hearing protection
Answer: C. Irregular respiratory motion during acquisition
,Respiratory motion changes the position and phase of abdominal structures
during acquisition. The resulting inconsistencies can create ghosting and blurring.
6. Which technique can reduce respiratory motion artifacts during abdominal
MRI?
A. Increasing patient movement
B. Respiratory gating or breath-hold imaging
C. Increasing slice thickness in every sequence
D. Removing phase encoding
Answer: B. Respiratory gating or breath-hold imaging
Respiratory gating coordinates acquisition with a selected portion of the breathing
cycle, while breath-hold techniques acquire data during a period of reduced
respiratory motion.
7. Which artifact appears as alternating bright and dark lines near a sharp tissue
boundary?
A. Zipper artifact
B. Gibbs artifact
C. Wrap-around artifact
D. RF interference artifact
Answer: B. Gibbs artifact
Gibbs, or truncation, artifact results from incomplete sampling of high spatial
frequencies. It commonly appears as ringing near high-contrast interfaces.
8. Which change can reduce Gibbs artifact?
A. Reduce the acquisition matrix
B. Increase voxel size
C. Increase spatial sampling
D. Increase patient motion
, Answer: C. Increase spatial sampling
Increasing the matrix or otherwise acquiring additional high-spatial-frequency
information can reduce truncation effects and make Gibbs ringing less prominent.
9. What is the primary cause of chemical-shift artifact between fat and water?
A. Patient motion
B. Gradient failure
C. Different resonance frequencies of fat and water
D. Inadequate slice thickness
Answer: C. Different resonance frequencies of fat and water
Fat and water resonate at slightly different frequencies in a magnetic field. Their
frequency difference can cause spatial misregistration along the frequency-
encoding direction.
10. Which adjustment generally decreases the amount of chemical-shift
displacement?
A. Decrease receiver bandwidth
B. Increase TE only
C. Increase slice thickness
D. Increase receiver bandwidth
Answer: D. Increase receiver bandwidth
Increasing receiver bandwidth reduces the amount of spatial displacement
associated with the frequency difference between fat and water.
11. Which artifact is particularly pronounced around metallic implants?
A. Gibbs artifact
B. Susceptibility artifact
C. Respiratory artifact
D. Wrap-around artifact
