Abstract: A local magnetic resonance (MR) radio frequency (RF) coil (12, 70, 90) includes a fixed size coil housing (19, 72) with an internal opening (26) which receives a portion of a subject anatomy for imaging. The internal opening (26) includes a narrowed portion (28) and a divergent portion (30) which accommodates variable sizes of subject anatomy. A first size of antenna (84) is disposed in the housing (19, 72) adjacent the narrowed portion (28) of the opening and at least a second size of antenna (86) larger than the at least first sized antenna (84) adjacent the divergent portion of the opening.

Abstract: A magnetic resonance imaging apparatus includes: a radio frequency (RF) coil including an endring; a power source configured to respectively supply RF power to each of a first port and a second port of the endring; three probes arranged adjacent to the endring; a voltage detector configured to detect the amplitudes of respective voltages induced to each of the three probes; and a controller configured to estimate a current of the RF coil based on the detected amplitudes of the respective voltages.

Abstract: A magnetic resonance imaging apparatus includes: a radio frequency (RF) coil including an endring; a power source configured to respectively supply RF power to each of a first port and a second port of the endring; three probes arranged adjacent to the endring; a voltage detector configured to detect the amplitudes of respective voltages induced to each of the three probes; and a controller configured to estimate a current of the RF coil based on the detected amplitudes of the respective voltages.

Abstract: A magnetic resonance system includes a magnetic resonance scanner (8) and a magnetic resonance scan controller (24). A plurality of markers (40, 140) are attached to the subject to monitor motion of a portion of a subject within an examination region. A motion control unit receives motion data from the markers indicative of the motion and controls the magnetic scan controller to adjust scan parameters to compensate for the motion. In one embodiment, the marker (40) includes a substance (44) which resonates at a characteristic frequency in response to radio excitations by the magnetic resonance scanner. A controller (52) switches an inductive circuit (48, 50) disposed adjacent the substance between a tuned state and a detuned state.

Abstract: A local magnetic resonance (MR) radio frequency (RF) coil (12, 70, 90) includes a fixed size coil housing (19, 72) with an internal opening (26) which receives a portion of a subject anatomy for imaging. The internal opening (26) includes a narrowed portion (28) and a divergent portion (30) which accommodates variable sizes of subject anatomy. A first size of antenna (84) is disposed in the housing (19, 72) adjacent the narrowed portion (28) of the opening and at least a second size of antenna (86) larger than the at least first sized antenna (84) adjacent the divergent portion of the opening.

Abstract: A magnetic resonance system includes a magnetic resonance scanner (8) and a magnetic resonance scan controller (24). A plurality of markers (40, 140) are attached to the subject to monitor motion of a portion of a subject within an examination region. A motion control unit receives motion data from the markers indicative of the motion and controls the magnetic scan controller to adjust scan parameters to compensate for the motion. In one embodiment, the marker (40) includes a substance (44) which resonates at a characteristic frequency in response to radio excitations by the magnetic resonance scanner. A controller (52) switches an inductive circuit (48, 50) disposed adjacent the substance between a tuned state and a detuned state. In another embodiment, the motion sensor includes an accelerometer, a gyroscope, a motion sensor, or a Hall-effect element, and a controller (144) which gathers motion data generated by the element and provides temporary storage for the motion data.