Titlebook: MRI Physics for Radiologists; A Visual Approach Alfred L. Horowitz Book 1995Latest edition Springer Science+Business Media New York 1995 Ra

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Gradientsng how these different intensities are arranged in space to produce an image. There are a number of ways of doing this, but in this section, we will be concerned only with the most widely used method: two dimensional Fourier transform (“2DFT”) reconstruction.

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The Slice Select Gradientdient imposes a gradual change in the main magnetic field from the head to the foot end of the patient. If we graph the z gradient with the magnitude of the magnetic field on the y axis and the position along the long axis of the body on the x axis, then we obtain the straight line shown in the grap

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The Phase Encoding Gradiention just as we did for the x axis. However, if we did that, then we would not be able to uniquely specify whether a given frequency belonged to the x or the y axis, and the computer would get confused and render us an improper image reconstruction. So we must do something else, and in fact, all comm

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