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Summary: EPI
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Many benefits
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Single-shot EPI prevents motion corrupted images
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Very efficient acquisition scheme (fast!)
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Longer readout = more image artifacts
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Image distortions occur along the slow (Phase Encode)
direction, because the effective gradient strength is low
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Dealing with distortions
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Shimming (homogenize the magnetic field)
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Acquire a field-map (measure the field to correct distortions)
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Reduce readout length (high BW, parallel imaging)