Steering resonance along a trajectory

1. A method for generating a magnetic resonance image, the method including:

applying a radio frequency (RF) pulse to a specimen;

modulating a spatially varying magnetic field to move an isolated region of resonance along a rotational trajectory relative to the specimen;

acquiring data corresponding to the at least one region of resonance, wherein the data are spatiotemporally encoded data that are encoded with spatial coordinates in a spatial domain in a temporally dependent manner; and

reconstructing a representation of the specimen based on the spatiotemporally encoded data.

2. The method of claim 1 wherein reconstructing the representation of the specimen includes accessing data corresponding to experimental parameters.

3. The method of claim 1 wherein reconstructing the representation of the specimen includes accessing data corresponding to time and position.

4. The method of claim 1 wherein reconstructing the representation of the specimen includes using a transfer function.

5. The method of claim 1 wherein applying the radio frequency pulse includes applying a gapped pulse.

6. The method of claim 1 wherein applying the radio frequency pulse occurs simultaneously with acquiring data.

7. The method of claim 1 wherein applying the radio frequency pulse includes applying a pulse using multiple transmit channels.

8. The method of claim 7 wherein applying the pulse using multiple transmit channels includes applying a plurality of magnitude and phase values.

9. The method of claim 1 wherein acquiring data includes acquiring data corresponding to a plurality of trajectories.

10. The method of claim 1 further including modulating a parameter to spatially alter the trajectory.

11. The method of claim 1 further including modulating a parameter to temporally alter the trajectory.

12. The method of claim 1 further including modulating a second magnetic field.

13. The method of claim 1 further including modulating the radio frequency pulse.

14. The method of claim 1 wherein reconstructing includes solving an inverse problem.

15. The method of claim 1 wherein applying the radio frequency pulse includes applying a multiband pulse.

16. The method of claim 1 wherein acquiring data includes acquiring using multiple receiver channels.

17. The method of claim 1 wherein modulating the spatially varying magnetic field entails controlling the trajectory to have an angular velocity.

18. A method for generating a magnetic resonance image, the method including:

applying a radio frequency (RF) pulse to a specimen;

selecting a spatially varying magnetic field to position an isolated region of resonance along a rotational trajectory relative to the specimen;

acquiring data corresponding to the region of resonance, wherein the data are spatiotemporally encoded data that are encoded with spatial coordinates in a spatial domain in a temporally dependent manner; and

reconstructing a representation of the specimen based on the spatiotemporally encoded data.

19. A method of generating a magnetic resonance image, the method comprising:

selecting a rotational pathway relative to a specimen;

applying a radio frequency (RF) pulse to the specimen;

modulating a spatially varying magnetic field to move an isolated region of resonance along the rotational pathway;

acquiring data corresponding to the region of resonance, wherein the data are spatiotemporally encoded data that are encoded with spatial coordinates in a spatial domain in a temporally dependent manner; and

reconstructing a representation of the specimen based on the spatiotemporally encoded data.

20. The method of claim 19 further including modulating excitation to the specimen.

21. The method of claim 19 wherein acquiring data includes using a plurality of receiver coils to acquire data using a parallel imaging algorithm.

22. The method of claim 19 wherein acquiring data includes calculating a pseudoinverse of a magnetic transfer function.

23. The method of claim 19 further including compensating for B0 magnetic field inhomogeneity by adjusting at least one of RF amplitude, frequency, and a spatially varying magnetic field.

24. The method of claim 19 further including compensating for B1 magnetic field inhomogeneity by adjusting at least one of RF amplitude, frequency, and a spatially varying magnetic field.

25. A method of generating a magnetic resonance image, the method comprising:

identifying a rotational pathway relative to a specimen;

applying a radio frequency (RF) pulse to the specimen;

selecting a spatially varying magnetic field to position an isolated region of resonance along the pathway;

acquiring data corresponding to the region of resonance, wherein the data are spatiotemporally encoded data that are encoded with spatial coordinates in a spatial domain in a temporally dependent manner; and

reconstructing a representation of the specimen based on the spatiotemporally encoded data.

26. A system comprising:

a magnet configured to generate a magnetic field;

a spatially varying magnetic field generator configured to impose a controllable gradation within the magnetic field;

a pulse generator configured to provide radio frequency excitation to a region of interest within the magnetic field, the excitation configured to enable calculation of a magnetic resonance image;

a processor coupled to the spatially varying magnetic field generator and the pulse generator, the processor configured to generate an isolated region of resonance within the region of interest, the processor configured to control the spatially varying magnetic field generator and control the pulse generator to cause the region of resonance to move along a rotary trajectory; and

wherein the processor is configured to acquire spatiotemporally encoded data from the isolated region of resonance and to reconstruct an image from the spatiotemporally encoded data, wherein the spatiotemporally encoded data are encoded with spatial coordinates in a spatial domain in a temporally dependent manner.

27. The system of claim 26 wherein the processor is configured to manipulate a B0 field within the magnet.

28. The system of claim 26 wherein the processor is configured to manipulate a B1 field within the magnet.

29. The system of claim 26 wherein the region of resonance includes a stationary point.

30. The system of claim 26 wherein the region of resonance includes a point traversing the region of interest.