Spatial resolution MRI
Spatial resolution determines how "sharp" the image looks. Low resolution will give either fuzzy edges, or a pixelly appearance to the image.
In MRI, spatial resolution is defined by the size of the imaging voxels. Since voxels are three dimensional rectangular solids, the resolution is frequently different in the three different directions. The size of the voxel and therefore the resolution depends on matrix size, the fieldofview (FOV), and the slice thickness. The matrix size is the number of frequency encoding steps, in one direction; and the number of phase encoding steps, in the other direction of the image plane. Assuming everything else is constant, increasing the number of frequency encodings or the number of phase steps results in improved resolution. The frequency encoding depends on of how rapidly the FID signal is sampled by the scanner. Increasing the sampling rate results in no time penalty. Increasing the number of phase steps increases the time of the acquisition proportionately. This is why images that have fewer phase encodings than frequency encodings, e.g., 128x256 or 192x256 will be used.
The FOV is the size of the area that the matrix of phase and frequency encoding cover. Dividing the FOV by the matrix size gives you the inplane voxel size; hence, increasing the FOV in either direction increases the size of the voxels and decreases the resolution. Decreasing the FOV improves the resolution.
The slice thickness determines the depth of the voxel. This is almost always the largest dimension of the voxel in 2D imaging. Therefore, the resolution perpendicular to the image plane is the poorest. This is related to the maximum strength of the zgradient coils as well as time restraints limiting the number of slices available. 3D imaging utilising phase encoding in the z direction is capable of smaller slice thickness than 2D imaging but carries a time penalty proportional to the number of slices.
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Physics and Imaging Technology: MRI
 MRI (introduction)
 MRI physics
 MRI hardware
 signal processing

MRI pulse sequences (basics  abbreviations  parameters)
 spin echo sequences
 inversion recovery sequences
 gradient echo sequences
 fatsuppressed imaging sequences
 diffusion weighted sequences (DWI)

perfusionweighted imaging
 techniques
 derived values
 CSF flow studies
 susceptibilityweighted imaging (SWI)
 saturation recovery sequences
 echoplanar pulse sequences
 metal artifact reduction sequence (MARS)
 T1 rho
 spiral pulse sequences
 MR angiography (and venography)

MR spectroscopy (MRS)
 Hunter's angle
 lactate peak: resonates at 1.3 ppm
 lipids peak: resonate at 1.3 ppm
 alanine peak: resonates at 1.48 ppm
 Nacetylaspartate (NAA) peak: resonates at 2.0 ppm
 glutamineglutamate peak: resonate at 2.22.4 ppm
 gammaaminobutyric acid (GABA) peak: resonates at 2.22.4 ppm
 2hydroxyglutarate peak: resonates at 2.25 ppm
 citrate peak: resonates at 2.6 ppm
 creatine peak: resonates at 3.0 ppm
 choline peak: resonates at 3.2 ppm
 myoinositol peak: resonates at 3.5 ppm
 functional MRI (fMRI)
 MR fingerprinting

MRI artifacts
 MRI hardware and room shielding
 MRI software
 patient and physiologic motion
 tissue heterogeneity and foreign bodies
 Fourier transform and Nyqvist sampling theorem
 MRI contrast agents
 MRI safety