Abstract: Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.

Abstract: Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.

Abstract: Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.

Abstract: Systems and methods for generating a numerical model of the human head are provided. A numerical model may be created by generating a data array in a magnetic resonance modeling system, each cell of the array corresponding to a location in the head. The cells may be grouped into one or more regions, each group corresponding to a segment of the head. The cells of the array may be populated with values corresponding to tissue properties relevant to MR imaging. Tissue property values may be selected for each region based on one or more probability distributions. For each region and each tissue property, a value may be selected based on a corresponding probability distribution. Selected tissue property values may be input into cells in the array corresponding to the region with which the probability distribution is associated. The numerical model may be used as an input to an MRI simulator.

Abstract: Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.

Abstract: Systems and methods for estimating magnetic susceptibility of a patient through continuous motion in an MRI scanner are provided herein. In one or more examples, during the collection of data, the patient can be instructed to move their head or other part of the body in a continuous manner and for a fixed duration of time. During the fixed duration of time, magnitude a data from the RF signal can be received by one or more RF coils can be collected. The received and undersampled magnitude data can be converted to phase data which can then be converted to magnetic susceptibility. Thus magnetic susceptibility can be determined while allowing for continuous motion during the MRI scan, which can be more comfortable and feasible for the patient in contrast to techniques that require the patient to hold their body at a particular orientation in the scanner for a fixed duration of time.

Abstract: A gun lock has a user manipulatable proximate end and a distal end for insertion into a barrel of a firearm. The distal end is spaced from the proximate end by a distance sufficient to allow the distal end to enter the chamber of the firearm when the proximate end is adjacent to but spaced from the barrel of the firearm. The distal end has elements which respond to user manipulation to transit from a first state allowing the distal end to enter and withdraw from the chamber of the firearm and a second state which prevents the distal end from withdrawing from the chamber. With the distal end of the gun lock inserted into the chamber and then transiting to the second state the inability to withdraw the gun lock from the firearm prevents the firearm from normal use.

Abstract: A gun lock has a user manipulatable proximate end and a distal end for insertion into a barrel of a firearm. The distal end is spaced from the proximate end by a distance sufficient to allow the distal end to enter the chamber of the firearm when the proximate end is adjacent to but spaced from the barrel of the firearm. The distal end has elements which respond to user manipulation to transit from a first state allowing the distal end to enter and withdraw from the chamber of the firearm and a second state which prevents the distal end from withdrawing from the chamber. With the distal end of the gun lock inserted into the chamber and then transiting to the second state the inability to withdraw the gun lock from the firearm prevents the firearm from normal use.

Abstract: Systems and methods for generating a numerical model of the human head are provided. A numerical model may be created by generating a data array in a magnetic resonance modeling system, each cell of the array corresponding to a location in the head. The cells may be grouped into one or more regions, each group corresponding to a segment of the head. The cells of the array may be populated with values corresponding to tissue properties relevant to MR imaging. Tissue property values may be selected for each region based on one or more probability distributions. For each region and each tissue property, a value may be selected based on a corresponding probability distribution. Selected tissue property values may be input into cells in the array corresponding to the region with which the probability distribution is associated. The numerical model may be used as an input to an MRI simulator.

Abstract: A method for magnetic resonance (MR) phase imaging of a subject includes: (i) for each channel of a multi-channel MRI scanner, acquiring MR measurements at a plurality of voxels of the subject using a pulse sequence that reduces MR measurement phase error; and (ii) for each voxel, determining reconstructed MR phase from the MR measurements of each channel to form an MR phase image of the subject. The step of determining reconstructed MR phase may be performed for each of the voxels independently.

Abstract: Described here are systems and methods for estimating phase measurements obtained using a magnetic resonance imaging (MRI) system such that phase ambiguities in the measurements are significantly mitigated. Echo time spacings are determined by optimizing phase ambiguity functions associated with the echo time spacings. Data is then acquired using a multi-echo pulse sequence that utilizes the determined echo spacings. Phase measurements are then estimated and images are reconstructed using a reconstruction technique that disambiguates the phase ambiguities in the phase measurements.

Abstract: A method for magnetic resonance (MR) phase imaging of a subject includes: (i) for each channel of a multi-channel MRI scanner, acquiring MR measurements at a plurality of voxels of the subject using a pulse sequence that reduces MR measurement phase error; and (ii) for each voxel, determining reconstructed MR phase from the MR measurements of each channel to form an MR phase image of the subject. The step of determining reconstructed MR phase may be performed for each of the voxels independently.

Abstract: Described here are systems and methods for estimating phase measurements obtained using a magnetic resonance imaging (MRI) system such that phase ambiguities in the measurements are significantly mitigated. Echo time spacings are determined by optimizing phase ambiguity functions associated with the echo time spacings. Data is then acquired using a multi-echo pulse sequence that utilizes the determined echo spacings. Phase measurements are then estimated and images are reconstructed using a reconstruction technique that disambiguates the phase ambiguities in the phase measurements.

Abstract: A magnetic resonance imaging (MRT) method for jointly estimating an image degradation and reconstructing an image of a subject in which that image degradation is mitigated is provided. The MRI system is operated to acquire multiple different k-space data sets that are acquired with different acquisition parameters so as to modulate the image degradation to be estimated. Using an iterative process, the image degradation is estimated while jointly reconstructing an image in which the estimated image degradation is mitigated.

Abstract: A magnetic resonance imaging (MRT) method for jointly estimating an image degradation and reconstructing an image of a subject in which that image degradation is mitigated is provided. The MRI system is operated to acquire multiple different k-space data sets that are acquired with different acquisition parameters so as to modulate the image degradation to be estimated. Using an iterative process, the image degradation is estimated while jointly reconstructing an image in which the estimated image degradation is mitigated.

Abstract: A protective mask comprising an imperforate, transparent shield mounted on the brow and extending over the face of a person wearing the mask. The shield includes an anteriorly protruding portion spaced sufficiently away from the wearer's face to enable spectacles or other optical devices to be worn by the user. The anteriorly protruding portion includes an outwardly flaring upper portion and a downwardly flaring lower portion, with the junction between the upper and lower portions being a non-sharp, gradually curved section which minimizes the amount of visual distortion experienced by the user. Attached in a longitudinal fashion, adjacent each side edge of the shield, is a malleable, form-adjusting strip, the bending of which foreshortens the shield, causing it to bow-out anteriorally to accommodate the use of a variety of sized eyegear to be worn with the mask.