Switched array coils.

Switched array coils (SACs) are a useful tool in local coil imaging since they allow in a user-friendly manner one to make the best choice in the trade-off between field of view and signal-to-noise ratio. This is done by selecting the current path within a conductor array equipped with suitable switches. Since the switching can be controlled by the system, this allows changing of the coil dimensions within multislice sequences. Thus image quality can be improved due to smaller coil dimensions for a given slice and a larger area can be covered by electronically shifting this sensitive area. The principle can be applied to surface--as well as volume--coil designs.