On-line NMR imaging of a solid or liquid object undergoing continuous translational motion

Apparatus for gathering nuclear magnetic resonance imaging data comprising:

• a first field generating means for generating a spatially characterised, constant magnetic field B0 in an imaging unit volume having a redetermined length along a longitudinal axis thereof, the B0 field being substantially parallel to said longitudinal axis;
• a second field generating means for generating, in said imaging unit volume, a spatially characterised magnetic field gradient Gz substantially parallel to B0, and comprising a coil having adjacent loops thereof separated by a distance which increases as a function of the distance along the coil axis;
• a third field generating means for generating, within the imaging unit volume, radiofrequency field B1 pulses transverse to field B0, and comprising a cylindrical coil having a first series of loops in which the plane of each loop is tilted with respect to the cylinder axis so as to generate a field with a component perpendicular to the cylinder axis, and a second series of loops which generate a field which substantially eliminates a longitudinal component of the field generated by the first series of loops;
• receiver means for detecting nuclear magnetic resonance signals weighted with at least one selected nuclear magnetic resonance parameter from said object;
• wherein said first, second and third field generating means are all constructed to have mutually coaxial cylindrical geometry which construction can be generally extendable to an arbitrary length along said longitudinal axis.

Apparatus for gathering nuclear magnetic resonance imaging data comprising:

• a first field generating means for generating a spatially characterised, constant magnetic field B0 in an imaging unit volume having a predetermined length along a longitudinal axis thereof, the B0 field being parallel to said longitudinal axis;
• a second field generating means for generating, in said imaging unit volume, a spatially characterised magnetic field gradient Gz substantially parallel to B0;
• a third field generating means for generating, within the imaging unit volume, radiofrequency field B1 pulses transverse to field B0;
• receiver means for detecting nuclear magnetic resonance signals weighted with at least one selected nuclear magnetic resonance parameter from said object;
• wherein at least said second field generating means comprises a coil in which each successive adjacent loop along the longitudinal axis is separated from a preceding loop by a distance which increases along the longitudinal axis.

Apparatus for gathering nuclear magnetic resonance data for imaging comprising:

• a first field generating means for generating a spatially characterised, constant magnetic field B0, in an imaging unit volume having a predetermined length along a longitudinal axis thereof;
• conveyance means for conveying an object under analysis through said imaging unit volume at a predetermined velocity substantially along said longitudinal axis thereof;
• a second field generating means for generating, in said imaging unit volume, a spatially characterised, temporally constant magnetic field gradient Gz substantially parallel to the longitudinal axis;
• a third field generating means for generating, within the imaging unit volume, radiofrequency field B1 pulses transverse to field B0;
• receiver means for detecting nuclear magnetic resonance signals weighted with at least one selected nuclear magnetic resonance parameter from said object during a period in which said object is moving through said imaging unit volume at said predetermined velocity;
• and
• means for correcting said detected signals for a motional phase factor acquired from the movement of said object at said predetermined velocity through the imaging volume.