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10 Cards in this Set
- Front
- Back
What are the 3 things that are required to know where a signal is coming from
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First of all, the desired slice must be selected
Then, spatial information is encoded along the rows Finally, spatial information is encoded along the columns |
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How is decoding of the MR signal done
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Decoding of spatial information, included in the NMR signal as modifications of frequency and phase, is performed by an inverse Fourier Transform
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What is used to determine the location of a slice
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slice selection gradient (GSS)
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Which in each slice selection gradient what is done to further pinpoint where the signal is coming from
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Within this volume, the position of each point will be encoded vertically and horizontally by applying a phase encoding gradient (GPE), and a frequency-encoding gradient (GFE).
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What is spatial encoding referring to
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slice selection gradient
phase encoding gradient frequency encoding gradient |
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What gradient is usually done first
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First of all, a slice selection gradient (GSS) is used to select the anatomical volume of interest
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How are the 3 different gradients the same and different
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The different gradients used to perform spatial localization have identical properties but are applied at distinct moments and in different directions.
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What is an example of a gradient in the Z-axis
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Slice selection gradient
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What is an example of a gradient in the X-axis
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Left to Right
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What is an example of a gradient in the Y direction
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anterior posterior (relative to axial image)
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