Three-sided magnets for magnetic resonance imaging

The quest for open MRI magnets has so far been satisfied by designs that can be re-conduced to “C” or “H” configurations, whose cavities can be described as “two sided,” meaning that two surfaces only are actively generating the magnetic field in the region of interest. The low efficiency of these magnets can be increased giving an active role to the “third wall” of the cavity. We present here a configuration involving only planar coils. This layout avoids excessive folding and torsion of the wire and reduces the effect of the mechanical forces produced by the magnetic field.