Slice Orientation
CORRECT. Usually the slice selection gradient is applied in the z-axis—the head-foot direction in the scanner. But because a gradient magnetic field may be applied in any orientation, slices may be acquired at literally any angle or orientation in the patient. This is one strength of MRI. (The theoretical freedom of orientation is complicated in practice by other considerations such as image aliasing.)
Additional gradient magnetic fields are created by a number of shaped coil windings within the scanner housing. Specifically, the z-gradient is produced by coils based on a Maxwell pair and x- and y-gradients are produced by coils based on Golay-pair coil design. Oblique magnetic field gradients are produced by applying more than one physical gradient at a time. (Additionally, the main magnetic field is produced by coils based on Helmholtz pair design.)
INCORRECT. The ability of MRI to acquire oblique slices is one of its strengths.
Try again.
INCORRECT. The ability of MRI to acquire oblique slices is one of its strengths.
Try again.
Further reading on this topic:
Books: MRI From Picture to Proton p115
Online: Medcyclopaedia