Abstract: The present disclosure provides systems and methods for removing electromagnetic interference from low-field magnetic resonance images. In one aspect, a method can include projecting a low-field strength magnetic field toward an object of interest located within a field of view and transmitting a radio frequency pulse sequence to a radio frequency coil assembly configured to selectively excite magnetization in the object of interest within the field of view. The method can further include receiving an output signal from the radio frequency coil assembly during a signal acquisition period and receiving a sample signal from the radio frequency coil assembly during an interference period. The method can further include comparing the output signal and the sample signal to identify an interference component and adjusting the output signal based on the interference component.

Abstract: The present disclosure provides various devices, systems, and methods for active shimming for an MRI system. For example, an MRI system can a first gradient coil, a second gradient coil, a third gradient coil, and a permanent magnet. The permanent magnet is configured to generate a magnetic field B0 having a low field strength. A method for active shimming the MRI system can include a set of candidate shimming configurations with first current values associated with the first gradient coil, second current values associated with the second gradient coil, and third current values associated with the third gradient coil. The method further includes applying, for each candidate shimming configuration, a pulse sequence; acquiring, for each pulse sequence, a magnetic resonance (MR) signal; determining, for each MR signal, a signal bandwidth based on a frequency domain of the MR signal; and designating a shimming configuration for the MRI system.

Abstract: The present disclosure provides various devices, systems, and methods for iterative shimming in magnetic resonance imaging (MRI). In one aspect, a method of iterative shimming can include generating a field map of a magnetic field B0 from an MRI system. The MRI system can include a shim tray and an array of permanent magnets to generate the magnetic field B0. The shim tray can include slots to receive shim magnets. The method can further include shimming the MRI system by iteratively: applying the field map to a genetic algorithm to determine a set of slots to receive a set of shim magnets, installing the set of shim magnets in the set of slots, generating a next field map of the magnetic field B0, and either performing a next iteration based on the next field map or determining to not perform the next iteration based on the next field map.

Abstract: A system can include a magnetic resonance imaging (MRI) scanner and a surgical robot. The MRI scanner can include a permanent magnet array define a dome to surround an imaging region, or region of interest. The MRI scanner can be configured to generate an image of an anatomical structure (e.g. the head of a patient) positioned within the dome and imaging region thereof. The MRI scanner can include an opening for accessing the head of the patient. The surgical robot can include robotic arm. The surgical robot can be mounted to the MRI scanner. The surgical robot can be configured to pass through the opening to perform a surgical procedure on the patient.

Abstract: Various systems and methods for T2-weighted and/or diffusion weighted chirped-CPMG sequences are disclosed herein. In one aspect, a method can include projecting a magnetic field along a longitudinal axis and toward an object of interest and transmitting a radio frequency pulse sequence to a radio frequency coil assembly configured to selectively excite magnetization in the object of interest. The radio frequency pulse sequence can include a frequency-swept excitation pulse and a series of frequency-swept refocusing pulses following the excitation pulse. In some aspects, the radio frequency pulse sequence can include a frequency-swept recovery pulse following the series of refocusing pulses. In some aspects, the method can include transmitting a preparation radio frequency pulse sequence to the radio frequency coil assembly.

Abstract: The present disclosure provides various systems and methods for magnetic resonance imaging. In one aspect, a method for magnetic resonance imaging can include receiving k-space data sets acquired by radiofrequency (RF) coils. Each of the k-space data sets can correspond to a different one of the RF coils. Each of the k-space data sets can be truncated and/or under sampled. The method can further include generating partial images of a field of view based on the k-space data sets and generating an initial image based on the partial images. The initial image can be full image of the field of view. The method can further include applying an iterative image reconstruction technique to generate an updated image based on the initial image.

Abstract: The present disclosure provides systems and methods for deep learning super-resolution training and/or image generation for low-field and ultra-low field magnetic resonance imaging. In some aspects, a method includes obtaining a first image of a brain with a low-field strength magnetic resonance imaging system. The first image has a first resolution. The method further includes obtaining a deep learning brain model based on high-field strength images. The deep learning brain model can be configured to be applied by a neural network comprising a plurality of layers. The method further includes applying the deep learning brain model to the first image to generate a second image of the brain. The second image has a second resolution, and the second resolution is greater than the first resolution.

Abstract: The present disclosure provides systems and methods for magnetic resonance imaging using a radio frequency coil, such as, for example, an intracranial radio frequency coil. In at least one aspect, a system can include a surgical tool and a magnetic resonance imaging system. The surgical tool can include a distal end portion and a radio frequency reception coil attached to the distal end portion. The magnetic resonance imaging system can be configured to project a magnetic field within a field of view and intraoperatively image the radio frequency reception coil in the field of view.

Abstract: The present disclosure provides magnetic resonance phantom imaging phantoms and method of assembling thereof. In one aspect, a magnetic resonance imaging phantom can include a plurality of modular components. The plurality of modular components can include a first modular component, a second modular component, a shell, and a lid. The second modular component can be different than the first modular component. The shell can be structured to receive at least one modular component. The lid can be attachable to the shell to enclose the at least one modular component received within the shell.

Abstract: The present disclosure provides systems and methods for removing electromagnetic interference from low-field magnetic resonance images. In one aspect, a method can include projecting a low-field strength magnetic field toward an object of interest located within a field of view and transmitting a radio frequency pulse sequence to a radio frequency coil assembly configured to selectively excite magnetization in the object of interest within the field of view. The method can further include receiving an output signal from the radio frequency coil assembly during a signal acquisition period and receiving a sample signal from the radio frequency coil assembly during an interference period. The method can further include comparing the output signal and the sample signal to identify an interference component and adjusting the output signal based on the interference component.

Abstract: A magnetic resonance imaging (MRI) apparatus is disclosed. The MRI apparatus includes a plurality of magnetic elements affixed in a Halbach dome structure. The Halbach dome structure defines an access aperture configured to allow access to the patient's head to enable neural intervention and defines a patient opening configured to receive a patient's head. In various aspects, the Halbach dome comprises a plurality of access apertures and/or gaps that may be adjustable in size.