Which parameter combination will yield the best spatial resolution?

Spatial resolution in MRI is determined by several factors, including slice thickness and the matrix size. A smaller slice thickness allows for thinner sections of anatomy to be imaged, leading to improved clarity and detail. In conjunction with this, a larger matrix size means that the image is composed of more pixels, resulting in finer detail representation.

In this particular question, the combination that yields the best spatial resolution is characterized by a slice thickness of 3mm along with a 256 x 256 matrix. This matrix size not only supports a greater number of pixels but also enhances the ability to differentiate between closely spaced structures. The utilization of a smaller slice thickness of 3mm minimizes partial volume effects, whereby adjacent tissues can blend into a single pixel, further contributing to enhanced detail.

Therefore, the combination of a 3mm slice thickness and a 256 x 256 matrix is optimal for achieving the highest level of spatial resolution, allowing for precise imaging of anatomical structures.