Abstract: Aspects of the invention relate to generating an emission activity image as well as an emission attenuation map using an iterative updation based on both the raw emission projection data and the raw radiography projection data, and an optimization function. The outputs include an optimized emission activity image, and at least one of an optimized emission attenuation map or an optimized radiography image. In some aspects an attenuated corrected emission activity image is obtained using the optimized emission activity image, and the optimized emission attenuation map.

Abstract: Systems and methods for determining electrical properties using Magnetic Resonance Imaging (MRI) are provided. One method includes applying an ultra-short echo time (TE) pulse sequence in a Magnetic Resonance Imaging (MRI) system and acquiring a complex B1+B1? quantity from an object following the application of the ultra-short TE pulse sequence, where B1+ is a complex amplitude of a transmit radio-frequency (RF) magnetic field and B1? is a complex amplitude of a receive RF magnetic field. The method also includes estimating, with a processor, one or more electrical properties of the object using the complex amplitudes of the transmit RF magnetic field and the receive RF magnetic field.

Abstract: Systems and methods of classifying component tissues of magnetic resonance images, where the method includes performing a proton density weighted, short echo-time magnetic resonance imaging measurement over a first volume field-of-view region of interest (ROI), repeating a series refining the first volume field-of-view ROI into a plurality of subsequent smaller ROI volumes having respective smaller resolutions, reconstructing a complex image from the plurality of magnetic resonance imaging measurements, performing a bias correction on at least one of the plurality of subsequent smaller ROI volumes, and classifying the ROI volumes by tissue type based on the bias-corrected image signal, wherein at least one tissue type is bone. A non-transitory medium containing processor instructions and a system are disclosed.

Abstract: A system and method for tracking temperature changes in tissue and bone is disclosed. In one aspect, the temperature changes are tracked simultaneously with high spatial encoding and temporal efficiency. The method is robust in terms of B0 and chemical shift off-resonance, as well as insensitive to eddy currents for accurate temperature mapping. Zero TE (ZTE) based MR thermometry is utilized herein to extract temperature changes from proton density and T1 weighted images. Additionally, T1 signal contamination is corrected for by calibrating T1 and B0 by using a variable flip angle method to achieve temperature mapping in bone, aqueous and adipose tissue simultaneously.

Abstract: According to some embodiments, emission projection data and second source scan data are received. A prior map and a prior weight map are generated from second source scan data. A penalty function calculates voxel-wise differences between the prior map and a given image, transforms the voxel-wise differences and calculates a weighted sum of the transformed differences, using weights based on the prior weight map. Joint reconstruction of an emission image and an attenuation map proceeds iteratively and uses the penalty function.

Abstract: Imaging system and method are presented. Emission scan (ES) and anatomical scan (AS) data corresponding to a target volume in a subject are received. One or more at least partial AS images are reconstructed using AS data. An image-space certainty (IC) map representing a confidence level (CL) for attenuation coefficients of selected voxels in AS images and a preliminary attenuation (PA) map based on AS images are generated. One or more of selected attenuation factors (AF) in projection-space are initialized based on PA map. A projection-space certainty (PC) map representing CL for the selected AF is generated based on IC map. An emission image of the target volume is initialized. The selected AF and emission image are iteratively updated based on the ES data, PC map, initial AF, and/or initial emission image. A desired emission image and/or AF values are determined based on the iteratively updated AF and/or emission image.

Abstract: Imaging system and method are presented. Emission scan (ES) and anatomical scan (AS) data corresponding to a target volume in a subject are received. One or more at least partial AS images are reconstructed using AS data. An image-space certainty (IC) map representing a confidence level (CL) for attenuation coefficients of selected voxels in AS images and a preliminary attenuation (PA) map based on AS images are generated. One or more of selected attenuation factors (AF) in projection-space are initialized based on PA map. A projection-space certainty (PC) map representing CL for the selected AF is generated based on IC map. An emission image of the target volume is initialized. The selected AF and emission image are iteratively updated based on the ES data, PC map, initial AF, and/or initial emission image. A desired emission image and/or AF values are determined based on the iteratively updated AF and/or emission image.

Abstract: A system and method for estimating image intensity bias and segmentation tissues is presented. The system and method includes obtaining a first image data set and at least a second image data set, wherein the first and second image data sets are representative of an anatomical region in a subject of interest. Furthermore, the system and method includes generating a baseline bias map by processing the first image data set. The system and method also includes determining a baseline body mask by processing the second image data set. In addition, the system and method includes estimating a bias map corresponding to a sub-region in the anatomical region based on the baseline body mask. Moreover, the system and method includes segmenting one or more tissues in the anatomical region based on the bias map.

Abstract: Exemplary embodiments of the present disclosure are directed to scheduling positron emission tomography (PET) scans for a combined PET-MRI scanner based on an acquisition of MR scout images of a subject. An anatomy and orientation of the subject can be determined based on the MR scout images and the schedule for acquiring PET scans of the subject can be determined from the anatomy of the subject. The schedule generated using exemplary embodiments of the present disclosure can specify a sequence of bed positions, scan durations at each bed position, and whether respiratory gating will be used at one or more of the bed positions.

Abstract: In one embodiment, a method includes performing a magnetic resonance (MR) imaging sequence to acquire MR image slices or volumes of a first station representative of a portion of a patient; applying a first phase field algorithm to the first station to determine a body contour of the patient in the first station; identifying a contour of a first anatomy of interest within the body contour of the first station using the first phase field algorithm or a second phase field algorithm; segmenting the first anatomy of interest based on the identified contour of the first anatomy of interest; correlating first attenuation information to the segmented first anatomy of interest; and modifying a positron emission tomography (PET) image based at least on the first correlated attenuation information.

Abstract: Systems and methods of classifying component tissues of magnetic resonance images, where the method includes performing a proton density weighted, short echo-time magnetic resonance imaging measurement over a first volume field-of-view region of interest (ROI), repeating a series refining the first volume field-of-view ROI into a plurality of subsequent smaller ROI volumes having respective smaller resolutions, reconstructing a complex image from the plurality of magnetic resonance imaging measurements, performing a bias correction on at least one of the plurality of subsequent smaller ROI volumes, and classifying the ROI volumes by tissue type based on the bias-corrected image signal, wherein at least one tissue type is bone. A non-transitory medium containing processor instructions and a system are disclosed.

Abstract: Systems and methods for determining electrical properties using Magnetic Resonance Imaging (MRI) are provided. One method includes applying an ultra-short echo time (TE) pulse sequence in a Magnetic Resonance Imaging (MRI) system and acquiring a complex B1+B1? quantity from an object following the application of the ultra-short TE pulse sequence, where B1+ is a complex amplitude of a transmit radio-frequency (RF) magnetic field and B1? is a complex amplitude of a receive RF magnetic field. The method also includes estimating, with a processor, one or more electrical properties of the object using the complex amplitudes of the transmit RF magnetic field and the receive RF magnetic field.

Abstract: Embodiments of a method, a tracking system, an MRI system, and a non-transitory computer readable medium that stores instructions for simultaneous imaging and tracking are presented. A designated signal and one or more characteristics corresponding to a plurality of imaging gradient waveforms are received. Further, a tracking pulse sequence is synchronized with an imaging pulse sequence at a determined point based on the designated signal. The tracking pulse sequence is then applied simultaneously with the imaging pulse sequence for acquiring corresponding response signals from an interventional device that includes at least one tracking coil and a tracking source configured to generate response signals at a tracking resonant frequency different from an imaging resonant frequency. A location of the tracking coil within or outside body of a subject is determined based on the response signals received from the tracking source and the characteristics corresponding to the imaging gradient waveforms.

Abstract: Exemplary embodiments of the present disclosure are directed to scheduling positron emission tomography (PET) scans for a combined PET-MRI scanner based on an acquisition of MR scout images of a subject. An anatomy and orientation of the subject can be determined based on the MR scout images and the schedule for acquiring PET scans of the subject can be determined from the anatomy of the subject. The schedule generated using exemplary embodiments of the present disclosure can specify a sequence of bed positions, scan durations at each bed position, and whether respiratory gating will be used at one or more of the bed positions.

Abstract: Embodiments of a method, a tracking system, an MRI system, and a non-transitory computer readable medium that stores instructions for simultaneous imaging and tracking are presented. A designated signal and one or more characteristics corresponding to a plurality of imaging gradient waveforms are received. Further, a tracking pulse sequence is synchronized with an imaging pulse sequence at a determined point based on the designated signal. The tracking pulse sequence is then applied simultaneously with the imaging pulse sequence for acquiring corresponding response signals from an interventional device that includes at least one tracking coil and a tracking source configured to generate response signals at a tracking resonant frequency different from an imaging resonant frequency. A location of the tracking coil within or outside body of a subject is determined based on the response signals received from the tracking source and the characteristics corresponding to the imaging gradient waveforms.

Abstract: In one embodiment, a method includes performing a magnetic resonance (MR) imaging sequence to acquire MR image slices or volumes of a first station representative of a portion of a patient; applying a first phase field algorithm to the first station to determine a body contour of the patient in the first station; identifying a contour of a first anatomy of interest within the body contour of the first station using the first phase field algorithm or a second phase field algorithm; segmenting the first anatomy of interest based on the identified contour of the first anatomy of interest; correlating first attenuation information to the segmented first anatomy of interest; and modifying a positron emission tomography (PET) image based at least on the first correlated attenuation information.

Abstract: An imaging system including an imaging apparatus having a plurality of coils, wherein an imaging target is at least partially disposed proximate the coils with at least one excitation source providing pulse sequences. A switch switchably connects the pulse sequences from the excitation source to the coils and switchably connecting to spatially encoded images from the coils during data acquisition. There is an amplified radiation damping feedback section providing amplified radiation damping feedback to the imaging target, wherein the amplified radiation damping feedback provides recovery of longitudinal magnetization subsequent to the data acquisition, and a receiver section for processing the spatially encoded images.

Abstract: An apparatus, system, and method including a magnetic resonance imaging (MRI) apparatus includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly to acquire MR images, and a computer. The computer is programmed to apply a first off-resonant radio frequency (RF) pulse at a first frequency different than the resonant frequency to a plurality of nuclei excited at a resonant frequency, acquire a first signal from the plurality of nuclei after application of the first off-resonant RF pulse, determine a phase shift from the first signal based on the first off-resonant RF pulse, determine a B1 field based on the phase shift, and store the B1 field on a computer readable storage medium.

Abstract: An imaging system including an imaging apparatus having a plurality of coils, wherein an imaging target is at least partially disposed proximate the coils with at least one excitation source providing pulse sequences. A switch switchably connects the pulse sequences from the excitation source to the coils and switchably connecting to spatially encoded images from the coils during data acquisition. There is an amplified radiation damping feedback section providing amplified radiation damping feedback to the imaging target, wherein the amplified radiation damping feedback provides recovery of longitudinal magnetization subsequent to the data acquisition, and a receiver section for processing the spatially encoded images.

Abstract: An apparatus, system, and method including a magnetic resonance imaging (MRI) apparatus includes a magnetic resonance imaging (MRI) system having a plurality of gradient coils positioned about a bore of a magnet, and an RF transceiver system and an RF switch controlled by a pulse module to transmit RF signals to an RF coil assembly to acquire MR images, and a computer. The computer is programmed to apply a first off-resonant radio frequency (RF) pulse at a first frequency different than the resonant frequency to a plurality of nuclei excited at a resonant frequency, acquire a first signal from the plurality of nuclei after application of the first off-resonant RF pulse, determine a phase shift from the first signal based on the first off-resonant RF pulse, determine a B1 field based on the phase shift, and store the B1 field on a computer readable storage medium.