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30 Cards in this Set
- Front
- Back
What are the advantages to an increase in TR?
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Increased SNR
Increased number of slices per acquisition |
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What are the disadvantages to an increase TR?
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Increased scan time
Decreased T1 weighting |
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What are the advantages to a decrease in TR?
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Decreased scan time
Increased T1 weighting |
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What are the disadvantages to a decrease in TR?
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Decreased SNR
Decreased number of slices per acquisition |
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What are the advantages of an increase in TE?
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Increased T2 weighting
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What are the disadvantages of an increase in TE?
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Decreased SNR
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What are the advantages of a decreased TE?
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Increased SNR
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What are the disadvantages of a decreased TE?
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Decreased T2 weighting
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What are the advantages of increased NEX?
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Increased SNR of all tissues
REduced flow artifact due to signal averaging |
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What are the disadvantages of increased NEX?
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Direct proportional increase in scan time
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What are the advantages of decreased NEX?
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Direct proportional decrease in scan time
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What are the disadvantages of decreased NEX?
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Decreased SNR in all tissues
Increased flow artifact due to less signal averaging |
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What are the advantages of increasing slice thickness?
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Increased SNR in all tissues
Increased coverage of anatomy |
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What are the disadvantages of increasing slice thickness?
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Decreased spatial resolution and partial voluming in slice select direction
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What are the advantages of decreasing slice thickness?
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Increased spatial resolution and reduced partial voluming in slice select direction
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What are the disadvantages of decreasing slice thickness?
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Decreased SNR in all tissues
Increased flow artifact due to less signal averaging |
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What are the advantages of increasing the FOV?
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Increased SNR
Increased coverage of anatomy |
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What are the disadvantages of increasing the FOV?
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Decreased spatial resolution
Decreased likelihood of aliasing |
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What are the advantages of decreasing the FOV?
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Decreased SNR in all tissues
Decreased coverage of anatomy |
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What are the disadvantages of decreasing the FOV?
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Increased spatial resolution
Increased likelihood of aliasing |
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What are the advantages of increasing the Matrix?
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Increased spatial resolution
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What are the disadvantages of increasing the matrix?
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Increased scan time
Decreased SNR if pixel size decreases. If pixel size remains the same, SNR will increase because more phase encodings are performed. |
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What are the advantages of decreasing the matrix?
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Decreased scan time
Increased SNR in all tissues if pixel size increases. If pixel size remains the same, SNR decreases as fewer phase encodings are performed. |
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What are the disadvantages of decreasing the matrix?
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Decreased spatial resolution
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What are the advantages of increasing receive bandwidth?
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Decrease of minimum TE
Decrease in chemical shift |
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What are the disadvantages of increasing receive bandwidth?
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Decreased SNR
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What are the advantages of decreasing receive bandwidth?
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Increased SNR
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What are the disadvantages of decreasing receive bandwidth?
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Increase in minimum TE
Increase in chemical shift |
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How could you increase SNR?
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Increase TR
Decrease TE Increase slice thickness Increase FOV Decrease Matrix (if pixel size increases) Decrease Bandwidth |
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How could you decrease scan time?
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Decrease TR
Decrease NEX Decrease Matrix |