Magnetic resonance imaging

Claim 3

The method of claim 1 including using a hook-like opposite going gradient pulse section integral to the beginning of said view gradient, said hook-like section covering a relatively small area.

Claim 4

The method of claim 2 wherein the step of generating a signal from the spins comprises using an echo producing scan sequence.

Claim 5

The method of claim 3 wherein said signal is truncated comprising most of the central portion of the signal and one wing of the usual two wings.

Claim 6

The method of claim 4 including the step of phase correcting said full image data.

Claim 7

The method of claim 5 including the steps of breaking a single side encoded signal into component parts comprising one wing and the central section and constructing the other wing by conjugation.

Claim 10

The method of claim 7 and the step of converting said method for providing motion insensitive scanning to a method of acquiring signals only from moving spins.

Claim 11

The method of claim 8 wherein said step of converting includes applying positive and negative motion encoding gradient pulses.

Claim 12

An arrangement for providing motion insensitive scanning in a magnetic resonance imaging system, said arrangement comprising: means for generating a large static magnetic field into which patient is inserted for aligning spins in the patient, means for subjecting the patient in the large static magnetic field to an RF pulse for tipping the aligned spins in the patient away from alignment, said tipped spins have at least a projection in a plane perpendicular to the direction of the aligned spins, said tipped spins rephasing in said plane perpendicular to the direction of the aligned spins, means for rephasing said dephasing spins to provide an echo signal, single-side encoding means for applying gradient pulses to the patient to localize the source of the echo signal in the patient, said echo signal including a leading wing having a relatively low magnitude a central section wherein the amplitude rises to an apex and the decays to a lagging wing also having a relatively low magnitude, said single-side encoding means for generating gradient pulses including means for applying a view gradient pulse that begins its maximum amplitude after said leading wing section and before the apex of the central portion of said signal, means for detecting the signal, and Fourier analysis means using said detected signal to reconstruct an image, and Fourier analysis means comprising half Fourier transform means, and means for conjugating the data resulting from the half-Fourier transform means to acquire full image data that is insensitive to motion thereby significantly reducing motion artifacts.

Claim 13

An arrangement for providing motion insensitive scanning in a magnetic resonance imaging system, said arrangement comprising: means for generating a large static magnetic field into which patient is inserted for aligning spins in the patient, means for subjecting the patient in the large static magnetic field to an RF pulse for tipping the aligned spins in the patient away from alignment, said tipped spins have at least a projection in a plane perpendicular to the direction of the aligned spins, said tipped spins rephasing in said plane perpendicular to the direction of the aligned spins, means for rephasing said dephasing spins to provide an echo signal, single-side encoding means for applying gradient pulses to the patient to localize the source of the echo signal in the patient, said echo signal including a leading wing having a relatively low magnitude a central section wherein the amplitude rises to an apex and the decays to a lagging wing also having a relatively low magnitude, said single-side encoding means for generating gradient pulses including means for applying a view gradient pulse that begins its maximum amplitude after said leading wing section and before the apex of the central portion of said signal, means for detecting the signal, and Fourier analysis means using said detected signal to reconstruct an image, and Fourier analysis means comprising half Fourier transform means, and means for conjugating the data resulting from the half-Fourier transform means to acquire full image data that is insensitive to motion thereby significantly reducing motion artifacts.

Claim 14

The system of claim 10 including means for applying a hook-like opposite going gradient pulse section integral to the beginning of said view gradient, said hook-like section covering a relatively small area.

Claim 15

The system of claim 10 wherein said detected signal is truncated comprising most of the central portion of the signal and one wing of the usual two wings.

Claim 16

The system of claim 12 including means for phase correcting said full image data.

Claim 17

The system of claim 13 including means for breaking a single side encoded signal into component parts comprising one wing section and the central section and means for constructing the other wing section by conjugating the measured portion.

Claim 18

The system of claim 10 and means for converting said motion insensitive scanning which acquires signals from moving spins and stationary spins to moving spin scanning which acquires signals only from moving spins.

Claim 19

The system of claim 15 wherein means for converting includes means for applying positive and negative motion encoding gradient pulses.

Claim 22

The system of claim 17 wherein said view gradient has a small area negative hook-like section followed by a positive mesa like section, half of a center portion of the signal and the lagging wing section being acquired during said positive mesa like section.