Surface coil for MR imaging with vertical magnetic field

Various surface coils are used in a horizontal magnetic field system. However, there is no surface coil in practical use for a vertical magnetic field system, because of difference of acquired signal direction. The basic configuration of a surface coil is an arrangement of two pair of loops with opposite electric current direction. The authors present a coil design that allows one to obtain a large field of view and high sensitivity. Optimization of coil geometry and size was decided by means f computer simulation. The authors have built a rectangular surface coil approximately 35 cm long, 25 cm wide, and 1 cm thick. The overall conducting pass length of the coil is less than 180 cm, with an inductance of approximately 1.2 μH at 8.5 MHz, and impedance of 800Ω The authors have developed a practical surface coil for a vertical magnetic field system. This coil has been clinically evaluated and obtained high image quality in the thoracic spine without motion artifacts