Patent ID: 6316941
Filing Date: 2001-11-13
Classification: G01R

Abstract:
A magnetic resonance apparatus having a main magnet which generates a main magnetic field along a main magnetic field axis through an examination region, a radio frequency (RF) transmitter and an RF coil assembly which performs at least one of exciting magnetic resonance dipoles within the examination region and receiving magnetic resonance signals from the resonating dipoles, and a receiver which receives and demodulates the magnetic resonance signals, the RF coil assembly comprising:a pair of end rings interrupted by a plurality of reactive elements, said end rings disposed in displaced parallel planes along a coil axis, said coil axis being orthogonal to the main magnetic field axis;a plurality of spaced rungs electrically interconnecting said end rings to define a generally cylindrical volume, the rungs supporting a first resonance mode and the end rings supporting an end ring resonant mode, the first resonance mode and the end ring resonance mode being a common RF frequency and the end ring mode being sensitive to RF components that are parallel to the coil axis and perpendicular to the main magnetic field axis and the first resonance mode being sensitive to RF components that are perpendicular to the coil axis and the main magnetic field axis;said end rings and said rungs being supported by a dielectric former;a conductive loop inductively coupled to both end rings;a first sampling port for sampling the first resonance mode; anda second sampling port for sampling the end ring resonance mode.