MRI of extremities using perforated single-turn solenoids

A class of single-turn solenoids that permits magnetic imaging of the extremities in horizontal bore magnets with improved coupling between the imaged anatomy and the rf section of the imager is described and demonstrated. These devices differ from more conventional designs primarily by the placement of one or more access holes in the side of the generally cylindrical resonant structure to permit extremity insertion. The image quality is excellent, rf efficiency and homogeneity are good, and signal-to-noise is high, permitting rapid acquisition of magnetic images with small fields of view.