Final answer:
In MRI, the placement of the signal collected in k-space depends on the data acquisition sequence. This mathematical representation of signal information corresponds to spatial locations in the image. Different sampling schemes result in different patterns of signal placement in k-space.
Step-by-step explanation:
In the context of k-space, the placement of the signal collected depends on the type of data acquisition sequence used. In MRI (Magnetic Resonance Imaging), k-space is a mathematical representation of the signal information obtained during scanning. Each point in k-space corresponds to a specific frequency and phase shift, which corresponds to a spatial location in the image.
For example, in MRI using a Cartesian sampling scheme, the collected signal is placed on a grid in k-space, with the low frequency components near the center and the high frequency components towards the edges. In other acquisition schemes, such as radial or spiral, the placement of the collected signal in k-space follows a different pattern.
These different patterns of signal placement in k-space allow for different imaging techniques, such as contrast weighting and parallel imaging, to be applied during image reconstruction.