Magnetic field shimming of a permanent magnet using a combination of pieces of permanent magnets and a single-channel shim coil for skeletal age assessment of children

► Active shimming using a single-channel (SC) shim coil was combined with passive shimming. ► Easy to design and fabricate the SC shim coil. ► Further correction beyond the limit of passive shimming was obtained by using the SC shim coil. ► The system design was applied to image extremities of humans, in particular a child's hand.