Abstract: An apparatus for MRI having an RF birdcage coil and an RF shield is disclosed. The RF birdcage coil includes a coil axis, an end ring portion disposed about the axis, and a plurality of legs disposed parallel to the axis and in signal communication with the end ring portion. The RF shield is disposed about the coil and is in signal communication therewith. The shield includes a cylindrical conductive sheet having first and second ends, and a plurality of sets of discontinuous slots disposed about the cylindrical sheet and running between the first and second ends, wherein a region of discontinuity within a set of the slots is aligned with the end ring portion.

Abstract: A radio frequency space cooling system (11) for a magnetic resonance imager system (10) includes a thermal energy transfer device (78). The energy transfer device (78) reduces the temperature of a cooling fluid (86) within the cooling system (11). A cooling element (82) is coupled to the energy transfer device (78) and extends along a patient bore (15) between a radio frequency shield (22) and a radio frequency coil (20) of the magnetic resonance imager system (10). The cooling element (82) has a channel (90) for passage of the cooling fluid (86).

Abstract: An imaging coil (12) includes multiple end rings (52). A center ring (53) extends parallel to and is coupled between the end rings (52). Multiple legs (86) are coupled between the end rings (52) and the center ring (53). The end rings (52) may have a first radius (R1) that is greater than a second radius (R2) of the center ring (53). The imaging coil (12) may include more than 16 legs. The imaging coil (12) may include multiple capacitor groupings (98) coupled along the end rings (52), each capacitor grouping (98) has multiple capacitors (102) with a coverage area width (W) greater than 5.0 cm. The center ring (53) may be coupled to a ground reference (110) and has low impedance such that the center ring (53) is effectively shorted to the ground reference (110).

Abstract: An integrated quadrature splitter-combiner and balun comprising: a transmission line balun operably connected to a first port and a second port; a first capacitor operably connected across the transmission line balun; a second capacitor operably connected to the first port and said balun; and a third capacitor operably connected to the second port and the balun. The second capacitor, the third capacitor, and the transmission line balun combine to form an RF splitter-combiner to split a balanced RF signal received at the first port into a first and second unbalanced quadrature RF signal transmitted at the second port and combines the first and second unbalanced quadrature RF signals received at the second port into the balanced RF signal transmitted at the first port.

Abstract: An integrated quadrature splitter-combiner and balun comprising: a transmission line balun operably connected to a first port and a second port; a first capacitor operably connected across the transmission line balun; a second capacitor operably connected to the first port and said balun; and a third capacitor operably connected to the second port and the balun. The second capacitor, the third capacitor, and the transmission line balun combine to form an RF splitter-combiner to split a balanced RF signal received at the first port into a first and second unbalanced quadrature RF signal transmitted at the second port and combines the first and second unbalanced quadrature RF signals received at the second port into the balanced RF signal transmitted at the first port.