Patent ID: 6452394
Filing Date: 2002-09-17
Classification: G01R

Abstract:
A magnetic resonance imaging apparatus in which a main magnetic field through an imaging region sets a resonance frequency of dipoles in the imaging region, the apparatus comprising:at least one radio frequency transmit coil which selectively transmits RF pulses into the imaging region during an RF transmit phase, the at least one radio frequency transmitter coil being tuned to a first frequency that is different from the resonance frequency; the transmit coil including a tuning circuit which shifts a tuned frequency of the transmit coil between the resonance frequency during the transmit phase and the first frequency, during an RF receive phase; at least one radio frequency receive coil tuned to the resonance frequency to detect magnetic resonance signals from resonating dipoles of a subject located in the imaging region; a gradient coil assembly which spatially encodes resonating dipoles in the imaging region with magnetic field gradients superimposed on the main magnetic field; at least one receiver which demodulates the received resonance signals from the at least one radio frequency receive coil; and, a reconstruction processor which reconstructs the received resonance signals into electronic image representation.