Design of a Four-Coil Surface Array for in Vivo Magnetic Resonance Microscopy at 600

ABSTRACT: The design and construction of a four-coil surface array for operation at 600 MHz is described. A capacitor-segmented single loop is used as the transmit coil. Novel features of the coil design include the use of varactor diodes in the transmit and receive coils for coil isolation and impedance matching. Isolation of greater than 20 dB between individual coils in the array was achieved without the use of low/high input impedance preamplifiers, and greater than 25 dB isolation was realized between the transmit coil and each element of the array. High-resolution in vivo images of mouse spinal cord using thi