Systems and methods for performing magnetic resonance imaging with reduced operator interaction
Techniques are provided for imaging a subject. A magnetic resonance imaging (MRI) system may use at least one RF coil to generate an initial MR data set for an initial image of the subject. The MRI system may use the initial MR image to determine a difference in orientation between a current orientation of the subject in the initial MR image and a target orientation of the subject. The MRI system may use the determined difference in orientation to determine an adjustment to a gradient pulse sequence for controlling at least one gradient coil. The MRI system may apply the determined adjustment to the gradient pulse sequence to obtain an adjusted gradient pulse sequence. The MRI system may generate an adjusted MR data set using the adjusted gradient pulse sequence, and a second MR image of the subject using the adjusted MR data set.
1 . A low-field magnetic resonance (MR) imaging (MRI) system for imaging a subject, the MRI system comprising:
at least one gradient coil;
at least one radio-frequency (RF) coil; and
at least one controller configured to:
generate, using the at least one RF coil, an initial MR data set of the subject; and
determine, based at least on the initial MR data set of the subject, whether a percentage of slices of the initial MR data set that contain signal is below a threshold for use in assessing subject positioning;
wherein a strength of a B 0 magnetic field generated by the MRI system is greater than or equal to 50 mT and less than or equal to 0.1 T.
2 . At least one non-transitory computer-readable storage medium having encoded thereon executable instructions that, when executed by at least one computer hardware processor, cause the at least one computer hardware processor to perform a method for imaging a subject using a low-field magnetic resonance (MR) imaging (MRI) system, the low-field MRI system comprising at least one gradient coil, at least one radio-frequency (RF) coil, and at least one controller, the method comprising:
generating, using the at least one RF coil, an initial MR data set of the subject; and
determining, based at least on the initial MR data set of the subject, whether a percentage of slices of the initial MR data set that contain signal is below a threshold for use in assessing subject positioning;
wherein a strength of a B0 magnetic field generated by the MRI system is greater than or equal to 50 mT and less than or equal to 0.1 T.
3 . The MRI system of claim 1 , wherein the at least one controller is further configured to determine, based at least on the initial MR data set, a difference in orientation between a current orientation of the subject and a target orientation of the subject.
4 . The MRI system of claim 1 , wherein the at least one controller is further configured to:
based at least on the initial MR data set and/or an anatomy that the subject comprises, identify one or more candidate pulse sequences for controlling the at least one RF coil, and
generate MR data using the identified one or more candidate pulse sequences.
5 . The MRI system of claim 1 , wherein the threshold percentage is about 75%.
6 . The MRI system of claim 1 , wherein the at least one controller is further configured to, when the percentage of slices is below the threshold, determine that the subject is improperly positioned.
7 . The MRI system of claim 1 , wherein the at least one controller is further configured to, when the percentage of slices is below the threshold, generate an indication to a user that the subject is improperly positioned.
8 . The MRI system of claim 1 , wherein the at least one controller is further configured to, when the percentage of slices is below the threshold, generate instructions for repositioning the subject.
9 . The MRI system of claim 1 , wherein the at least one controller is further configured to, when the percentage of slices is below the threshold, recommend repositioning of the subject.
10 . The non-transitory computer-readable storage medium of claim 2 , the method further comprising, when the percentage of slices is below the threshold, performing one or more of:
determining that the subject is improperly positioned;
generating an indication to a user that the subject is improperly positioned;
generating instructions for repositioning the subject; or
recommending repositioning of the subject.
11 . The MRI system of claim 3 , wherein the at least one controller is further configured to generate an initial MR image based at least on the initial MR data set, wherein determining the difference in orientation between the current orientation of the subject and the target orientation of the subject at least in part comprises comparing the initial MR image of the subject to a template MR image having the target orientation.