MRI method apparatus for imaging a field of view which is larger than a magnetic field
AssigneeThe Board of Trustees of the Leland Stanford Junior University
InventorsNorbert Joseph Pelc, Marcus Tedrow Alley
Life of this patent
Estimating the term…
Abstract
In a magnetic resonance imaging system, an extended field of view through an object is realized with a magnet having a smaller homogeneous field of view by translating the object through the homogeneous field while exciting nuclear spins within the object and detecting MRI signals with a plurality of coils which translate through the homogeneous field with the object. In a preferred embodiment, the plurality of receiver coils overlap. The table and object can continuously move through the homogeneous volume during nuclear excitation and MRI signal detection. A computer adjusts the MRI signals for the effect of changes in table position between signal acquisitions and compensate for phase shift in received signals.
Claims11
Apparatus for magnetic resonance imaging comprising:
- a) a magnet for establishing a static magnetic field in a first volume,
- b) a plurality of coils for establishing magnetic gradients in the first volume,
- c) RF coils for continually applying pulses to excite nuclear spins in the first volume while an object is translated through the first volume,
- d) a table for supporting an object,
- e) a plurality of receiver coils, each sensitive to a subvolume of the object, and
- f) means for translating the table through the first volume for imaging a plurality of subvolumes in the object as the plurality of subvolumes pass through the first volume, the plurality of receiver coils being translated with the table and detecting MRI signals for a subvolume at a plurality of times and at a plurality of table positions within the first volume, and the sum of the subvolumes being larger than the first volume.
A method of obtaining MRI signals from an extended field of view through an object where the extended field of view is larger than the homogenous volume of the magnetic field in a MRI system, the method comprising the steps of:
- a) placing the object to be imaged on a table which is translatable through the volume of magnetic field,
- b) providing a plurality of receiver coils, each sensitive to a subvolume of the object, which are translatable with the table whereby MRI signals can be detected by each receiver coil when in the volume of magnetic field,
- c) exciting nuclear spins in the plurality of volumes in the object while the object is translated through the volume of magnetic field,
- d) translating the object through the volume of magnetic field for imaging a plurality of subvolumes in the object, and
- e) detecting MRI signals for each subvolume at a plurality of table positions within the first volume.
Dependencies are inferred from the claim text.