NMR scanner with motion zeugmatography

Claim 2

A gyromagnetic resonance instrument which performs a measurement cycle by applying a transverse excitation signal to a gyromagnetic material and to thereby impart a transverse magnetic moment thereto, and which produces a FID signal responsive to emissions by the transversely magnetized gyromagnetic material, charaterized by means (10, 11, 12, 16 to 20) for motion sensitizing a FID signal in which a motion sensitizing magnetic field gradient F is applied to the gyromagnetic material for a period of time 2T after its transverse excitation and prior to the production of the FID signal, and wherein the motion sensitizing magnetic field gradient F has alternating polarity with respect to the gyromagnetic material such that its integral over the time period 2T is substantially zero.

Claim 3

The instrument as recited in claim 1 in which the motion sensitizing magnetic field gradient F is substantially anti-symmetrical with respect to time T during the time period 2T.

Claim 4

The instrument as recited in claim 1 or 2 which includes means (10, 11, 12, 16 to 20) for applying a magnetic field gradient G to the gyromagnetic material such that the FID signals which are emitted from a selected location therein are frequency encoded during each measurement cycle and the motion sensitized FID signals are thereby also position sensitized.

Claim 5

The instrument as recited in claim 3 in which the means for generating said field gradients G and F both employ the same set of gradient coils (10, 11, 12) which are positioned around the gyromagnetic material.

Claim 6

The instrument as recited in anyone of the preceding claims which includes: processor means (20) for performing an inverse Fourier transform on the motion sensitized FID signals to produce data indicative of motion intensity in the direction of the magnetic field gradient F.

Claim 7

The instrument as recited in anyone of the claims 1 to 5 in which the direction and magnitude of the motion sensitizing magnetic field gradient F is altered for successive measurement cycles to produce a corresponding set of motion sensitized FID signals, and which includes: processor means (20) for receiving the set of motion sensitized FID signals and performing an inverse Fourier transform thereon to produce a corresponding set of output data indicative of motion intensity in the directions of the magnetic field gradient F; and display means (27) connected to receive the output data and produce an image.

Claim 10

The method as recited in claim 7 in which a posi- tion sensitizing magnetic field gradient G is applied to the gyromagnetic material while the FID signal is being produced.

Claim 11

The method as recited in claim 7 which includes: processing the FID signal by performing an inverse Fourier transform thereon; and displaying the processed FID signal.

Claim 12

An NMR scanner comprising: means (1, 15, 20) for generating a polarizing magnetic field B within a gyromagnetic material; means (7, 21, 22) for generating an excitation magnetic field B 1 which produces a transverse magnetic moment in the gyromagnetic material; means (7, 22, 23) for sensing a FID signal produced by the gyromagnetic material excited by said excitation magnetic field B 1 ; and means (10, 11, 12, 16 to 20) for generating a position magnetic field gradient G in the gyromagnetic material to position sensitize the sensed FID signal and to thereby link the sensed FID signal to a location within the gyromagnetic material; characterized by means (10, 11, 12, 16 to 20) for generating a motion magnetic field gradient F in the gyromagnetic material to motion sensitize the sensed FID signal and to thereby link the sensed FID signal to the motion of the gyromagnetic material at said location; and processor means (20) for receiving sensed FID signals and producing an image which is modulated by the motion of the gyromagnetic material.

Claim 13

An NMR scanner comprising: means (1, 15, 20) for generating a polarizing magnetic field B within a gyromagnetic material; means (7, 21, 22) for generating an excitation magnetic field B 1 which produces a transverse magnetic moment in the gyromagnetic material; means (7, 22, 23) for sensing a FID signal produced by the gyromagnetic material excited by said excitation magnetic field B 1 ; and means (10, 11, 12, 16 to 20) for generating a position magnetic field gradient G in the gyromagnetic material to position sensitize the sensed FID signal and to thereby link the sensed FID signal to a location within the gyromagnetic material; characterized by means (10, 11, 12, 16 to 20) for generating a motion magnetic field gradient F in the gyromagnetic material to motion sensitize the sensed FID signal and to thereby link the sensed FID signal to the motion of the gyromagnetic material at said location; and processor means (20) for receiving sensed FID signals and producing an image which is modulated by the motion of the gyromagnetic material.

Claim 14

The NMR scanner as recited in claim 10 which includes control means (20) for cyclically generating a series of said FID signals, said control means including: means for altering the position magnetic field gradient G during successive cycles to link the series of FID signals with a succession of different locations in the gyromagnetic material.

Claim 15

The NMR scanner as recited in claim 11 in which the control means (20) alters the motion sensitizing magnetic field gradient F during successive cycles to link a series of FID signals at a specific location in the gyromagnetic material to a succession of different motion directions.

Claim 16

The NMR scanner as recited in claim 10 in which the means (10, 11, 12, 16 to 20) for generating the motion sensitizing magnetic field gradient F includes control means (20) for producing the field F during each measurement cycle over a period of time 2T with alternating polarity such that the integral of F over the time period 2T is substantially zero.

Claim 17

An NMR scanner which produces images related to the density distribution of a gyromagnetic phenomena in a gyromagnetic material, characterized by means (10, 11, 12, 16 to 20) for motion sensitizing NMR signals produced by the gyromagnetic material, such sensitizing including the application of a magnetic field gradient F of alternating polarity; and means (7, 20, 22 to 27) for receiving the motion sensitized NMR signals and producing image data which is related to the density distribution of the gyromagnetic phenomena in the material and which is modulated by the motion of the gyromagnetic material.

Claim 18

An NMR scanner which produces images related to the density distribution of a gyromagnetic phenomena in a gyromagnetic material, characterized by means (10, 11, 12, 16 to 20) for motion sensitizing NMR signals produced by the gyromagnetic material, such sensitizing including the application of a magnetic field gradient F of alternating polarity; and means (7, 20, 22 to 27) for receiving the motion sensitized NMR signals and producing image data which is related to the density distribution of the gyromagnetic phenomena in the material and which is modulated by the motion of the gyromagnetic material.

Claim 19

The NMR scanner as recited in claim 14 which includes processor means (20) for receiving said image data and producing an image which is related to the motion of the gyromagnetic material, but which is substantially independent of the density distribution of the gyromagnetic phenomena.