Abstract: The invention relates to a method and an apparatus for measuring the position and the orientation of an interventional device within a magnetic resonance imaging apparatus, the magnetic resonance image apparatus providing a static magnetic field B0 and magnetic field gradients with known magnetic flux densities and directions. The invention includes attaching a Faraday sensor to the interventional device, the Faraday sensor being connected to an optical measuring device. The method also includes using the optical measuring device for measuring the rotation of the plane of polarization of linearly polarized light in the Faraday sensor, while exposing the interventional device: (i) to the static magnetic field B0, and (ii) to the field gradients in all three directions of space in addition to the static magnetic field B0.

Abstract: The invention relates to a method and an apparatus for measuring the position and the orientation of an interventional device within a magnetic resonance imaging apparatus, the magnetic resonance image apparatus providing a static magnetic field B0 and magnetic field gradients with known magnetic flux densities and directions. The invention includes attaching a Faraday sensor to the interventional device, the Faraday sensor being connected to an optical measuring device. The method also includes using the optical measuring device for measuring the rotation of the plane of polarization of linearly polarized light in the Faraday sensor, while exposing the interventional device: (i) to the static magnetic field B0, and (ii) to the field gradients in all three directions of space in addition to the static magnetic field B0.

Abstract: An intervivo probe for a nuclear magnetic resonance tomographic apparatus has a measuring coil carried at one end of a thin plastic carrier, the coil having a cross-sectional area in the range of approximately a few square millimeters and a length of approximately 10 to 20 mm. The measuring probe is inserted in body organs, such as the brain, liver and kidney by means of cannulae or channels which have been surgically or otherwise inserted in the organ for other purposes.

Abstract: A local coil for detecting nuclear magnetic resonance signals from an examination subject, for spectroscopic analysis or image construction, has a coaxial conductor member shaped to form a first turn of the coil, with the inner conductor of the coaxial member exiting the jacket upon the completion of the first turn, and the unshielded inner conductor forming a second turn of the coil in the same winding direction as the first turn, and being connected to the jacket upon completion of the second turn. The coil is thus symmetrical with respect to ground, independent of frequency, and is balanced so that it can be directly connected to an asymmetrical coaxial cable.