A planar magnetic resonance imaging (MRI) magnet having a superconductive coil assembly including a toroidal-shaped coil housing which surrounds a bore, has a longitudinal axis, and contains at least three concentric, annular-shaped superconductive coils coaxially aligned with the axis. The coils produce a magnetic resonance imaging volume having a center located outside the bore. Preferably, the bore is generally completely filled with magnetic material, and the magnetic resonance imaging volume is located completely outside the bore which provides for improved patient and physician access during MRI-guided biopsy as well as during MRI imaging.