Titlebook: Cardiovascular MR Manual; Sven Plein,John Greenwood,John Phillip Ridgway Book 20111st edition Springer-Verlag London Limited 2011 Diagnost

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Image Space and k-Spacepoints in the signal and those in the image. A single data point in an MR signal contributes a particular attribute to the whole image. Conversely, a single pixel in the image may have contributions from all of the MR signals collected. Just as each pixel occupies a unique location in image space, e

FAWN

Imaging Parameters and Image Attributesthickness of the selected 2D image slice, also determine the voxel dimensions and hence the . (Fig.8.1). The voxel volume determines the number of protons that contribute to each pixel location. This strongly influences the size of the signal and is consequently a major determinant of ..

Systemic

Improving SNR with Surface Coils and Array Coils smaller region of interest, it is much more appropriate to use a smaller, more tailored, . (Fig. 9.1b). This has two advantages: 1. It is closer to the origin of the signal from the region of interest. 2. It detects less of the noise originating from outside of the region of interest.

Culmination

zonules

Gradient Echo Versus Spin EchoGradient Echo and Spin Echo pulse sequences (Fig. 11.1). In the case of spin echo, a 180° refocusing pulse is applied at a time equal to half the echo time. This reverses the effect of the field inhomogeneities and the amplitude of the transverse magnetization at the echo times dependent on the pure

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Black Blood Versus Bright Blood Imagingo produce the spin echo signal (Fig. 12.1). Both of these pulses are slice-selective but are separated by a time equal to half the echo time. The transverse magnetization of blood flowing through the slice that moves out of the slice between the two pulses is not refocused by the 180° pulse and does

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Evocative

Common Artifacts encoding process: While the number of phase encoding steps used to complete the image acquisition is sufficient to uniquely encode all the locations within the field of view, locations outside the field of view are not uniquely encoded (Fig.17.1). At the edge of the field of view, the phase increme