Systems and methods for volumetric acquisition in a single-sided MRI scanner
A method for performing magnetic resonance imaging is provided. The method includes providing a magnetic resonance imaging system comprising: a radio frequency receive system comprising a radio frequency receive coil, and a housing, wherein the housing comprises a permanent magnet for providing an inhomogeneous permanent gradient field, a radio frequency transmit system, and a single-sided gradient coil set. The method also includes placing the receive coil proximate a target subject; applying a sequence of chirped pulses via the transmit system; applying a multi-slice excitation along the inhomogeneous permanent gradient field; applying a plurality of gradient pulses via the gradient coil set orthogonal to the inhomogeneous permanent gradient field; acquiring a signal of the target subject via the receive system, wherein the signal comprises at least two chirped pulses; and forming a magnetic resonance image of the target subject.
1. A method for performing magnetic resonance imaging comprising:
projecting an inhomogeneous permanent gradient magnetic field to a target subject via a single-sided gradient coil set, wherein the gradient coil set is non-planar and oriented to partially surround the target subject;
placing a receive coil proximate the target subject;
applying a sequence of chirped pulses having a wide bandwidth;
selecting a slice selection gradient having the same wide bandwidth;
applying a multi-slice excitation technique along an axis of the inhomogeneous permanent gradient magnetic field;
applying a plurality of gradient pulses orthogonal to the inhomogeneous permanent gradient magnetic field;
acquiring a signal of the target subject via the receive coil; and
forming a magnetic resonance image of the target subject.
2. The method of claim 1 , wherein application of the sequence of chirped pulses, multi-slice excitation technique, and gradient pulses are each timed to refocus a magnetization of the inhomogeneous permanent gradient magnetic field at a time of acquisition of the signal.
3. The method of claim 2 , wherein each magnetization focuses in a region of interest, wherein the region of interest encompasses the target subject.
4. The method of claim 3 , wherein the region of interest has a diameter of 4 to 12 inches.
5. The method of claim 3 , wherein the imaging system further comprises a tuning box and a radio frequency transmit coil, wherein the tuning box is configured to alter frequency response of the transmit coil.
6. The method of claim 5 , wherein the transmit coil is non-planar and oriented to partially surround the region of interest.
7. The method of claim 3 , wherein the receive coil is a flexible coil configured to be affixed to an anatomical portion of a patient for imaging within the region of interest.
8. The method of claim 3 , wherein the receive coil is in one of a single-loop coil configuration, figure-8 coil configuration, or butterfly coil configuration, wherein the receive coil is smaller than the region of interest.
9. The method of claim 1 , wherein the sequence of chirped pulses comprise identical bandwidths and differing durations.
10. The method of claim 9 , wherein the sequence of chirped pulses have a bandwidth ranging from 1 kHz to 10 kHz, 10 kHz to 40 kHz, 40 kHz to 100 kHz, 100 kHz to 400 kHz, 400 kHz to 1 MHz, or any ranges of bandwidth thereof.
11. The method of claim 1 , wherein the sequence of chirped pulses are configured to produce a 1-dimensional signal along an axis of the permanent gradient field.
12. The method of claim 11 , wherein the 1-dimensional signal is a first 1-dimensional signal, and wherein the gradient pulses are configured to produce a second 1-dimensional signal and a third 1-dimensional signal that are orthogonal to each other and to the axis of the permanent gradient field.
13. The method of claim 1 , wherein the gradient pulses are configured for encoding spatial information to the signal.
14. The method of claim 1 , wherein the combination of the permanent gradient field and the sequence of chirped pulses are configured for slice selection in the permanent gradient and a frequency encoding gradient.
15. The method of claim 1 , wherein the target subject is an anatomical portion of a body.
16. The method of claim 1 , wherein the receive coil comprises an array of receive coils and each of the array of receive coils is configured for specific anatomical portion of a body.
17. The method of claim 1 , wherein the sequence of chirped pulses induce a signal in the target subject, and the signal is received by the receive coil.
18. The method of claim 1 , wherein the magnetic resonance imaging system further comprises a signal conditioning box and a control system, wherein the signal conditioning box is configured to turn the control system on and off with a blanking signal.
19. The method of claim 18 , wherein turning the system on and off with the blanking signal respectively enables and disables a radio frequency amplifier.