Abstract: A method of compressed sensing for multi-shell magnetic resonance imaging includes obtaining magnetic resonance imaging data, the data being sampled along multi-shell spherical coordinates, the spherical coordinates coincident with a plurality of spokes that converge at an origin, constructing a symmetric shell for each respective sampled multi-shell to create a combined set of data, performing a three-dimensional Fourier transform on the combined set of data to reconstruct an image, and de-noising the reconstructed image by iteratively applying a sparsifying transform on non-sampled data points of neighboring shells. The method can also include randomly under-sampling the imaging data to create missing data points. A system configured to implement the method and a non-transitory computer readable medium are also disclosed.

Abstract: A method of designing quiet variable-rate MRI slice-select pulses includes creating discretized first slice-select constant-amplitude gradient and RF waveforms, associating discretized time points having a first constant time increment with the first waveforms, selecting a scaling function that smooths the gradient waveform when multiplied together, multiplying the gradient and RF waveforms by the corresponding value of the scaling function to create second gradient and RF waveforms, dividing the time increment between the discretized time points by the corresponding value of the scaling function to create a remapped time increment, cumulatively summing the remapped time increments to create a remapped time scale, interpolating the second gradient and RF waveforms along the remapped time scale to form final gradient and RF waveforms, and providing the final gradient and RF waveforms for incorporation into an MRI pulse sequence.

Abstract: Magnetic resonance imaging systems and methods are provided. A method includes applying a slice selection gradient perpendicular to a desired slice plane and applying, substantially simultaneously with the slice selection gradient, a radiofrequency nuclear magnetic resonance excitation pulse having a bandwidth corresponding to the desired slice plane and a frequency corresponding to the frequency of protons present in the desired slice plane. The method also includes applying, during an encoding period and in a first direction, a phase encoding gradient having a phase encoding portion and a shearing portion and applying, during the readout period and in a second direction perpendicular to the first direction, a frequency encoding gradient having a portion having substantially the same shape as the shearing portion of the phase encoding gradient.

Abstract: A magnetic field may be applied to a subject having a plurality of tissues, including first and second tissues, causing a net longitudinal magnetization in the tissues. An inversion radio frequency pulse may be generated to invert the longitudinal magnetization from the tissues. Heart-rate timing information associated with a current ECG of the subject may be measured, and an inversion time TI may be dynamically calculated based at least in part on the heart-rate timing information. An excitation radio frequency pulse may then be generated. The generation of the excitation radio frequency pulse may occur a period of time after the generation of the inversion radio frequency pulse, and the period of time may be based on the dynamically calculated inversion time TI. Magnetic resonance imaging data may then be acquired.

Abstract: Exemplary embodiments of the present disclosure are directed to correcting lung density variations in positron emission tomography (PET) images of a subject using a magnetic resonance (MR) image. A pulmonary vasculature and an outer extent of a lung cavity can be identified in a MR image corresponding to a thoracic region of the subject in response to an intensity associated with pixels in the MR image. The pixels within the outer extent of the lung cavity are classified as corresponding to the pulmonary vasculature or the lung tissue. Exemplary embodiments of the present disclosure can apply attenuation coefficients to a reconstruction of the PET image based on the classification of the pixels within the outer extent of the lung cavity.

Abstract: A magnetic resonance (MR) imaging method includes acquiring MR signals having phase and magnitude at q-space locations using a diffusion sensitizing pulse sequence performed on a tissue of interest, wherein the acquired signals each include a set of complex Fourier encodings representing a three-dimensional displacement distribution of the spins in a q-space location. The signals each include information relating to coherent motion and incoherent motion in the q-space location. The method also includes determining a contribution by coherent motion to the phase of the acquired MR signals; removing the phase contribution attributable to coherent motion from the acquired MR signals to produce a complex data set for each q-space location and an image of velocity components for each q-space location; and producing a three-dimensional velocity image from the image of the velocity components.

Abstract: Systems and methods for correcting magnetic resonance (MR) data are provided. One method includes receiving the MR data and correcting errors present in the MR data due to non-uniformities in magnetic field gradients used to generate the diffusion weighted MR signals. The method also includes correcting errors present in the MR data due to concomitant gradient fields present in the magnetic field gradients by using one or more gradient terms. At least one of the gradient terms is corrected based on the correction of errors present in the MR data due to the non-uniformities in the magnetic field gradients.

Abstract: A method includes obtaining a plurality of magnetic resonance (MR) coil images of a subject of interest, each MR coil image being generated from one of an array of MR receiving coils; combining the plurality of coil images to generate an image estimate of the subject of interest; performing a multichannel blind deconvolution (MBD) process including: deriving coil sensitivity information for every one of the array of MR receiving coils based on the image estimate or a filtered image estimate derived from the image estimate; updating the image estimate or the filtered image estimate using the derived coil sensitivity information to generate an updated image estimate; and applying a homomorphic filter to the image estimate to derive the filtered image estimate, or to the updated image estimate to derive a filtered updated image estimate, or a combination thereof.

Abstract: A photonic system and method for optical data transmission in medical imaging system are provided. One photonic system includes a plurality of optical modulators having different optical resonance wavelengths and configured to receive electrical signals representative of a set of data from a medical imaging device. The photonic system also includes an optical waveguide interfacing with the plurality of optical modulators and configured to transmit an amplitude modulated beam of light at different frequencies to selectively modulate the plurality of optical modulators to transmit an encoded beam of light. The photonic system further includes receiver opto-electronics in communication with the optical waveguide configured to decode the encoded beam of light and convert the decoded beam of light into the electrical signals representative of the set of data.

Abstract: A system for inductively communicating signals in a magnetic resonance imaging system is presented. The system in one embodiment includes a first array of primary coils disposed on a patient cradle of the imaging system, and configured to acquire data from a patient positioned on the patient cradle. Additionally, the system includes a second array of secondary coils disposed under the patient cradle, wherein a number of secondary coils is less than or equal to the number of primary coils, wherein the first array of primary coils is configured to inductively communicate the acquired data to the second array of secondary coils.

Abstract: A magnetic resonance (MR) imaging method includes acquiring MR signals having phase and magnitude at q-space locations using a diffusion sensitizing pulse sequence performed on a tissue of interest, wherein the acquired signals each include a set of complex Fourier encodings representing a three-dimensional displacement distribution of the spins in a q-space location. The signals each include information relating to coherent motion and incoherent motion in the q-space location. The method also includes determining a contribution by coherent motion to the phase of the acquired MR signals; removing the phase contribution attributable to coherent motion from the acquired MR signals to produce a complex data set for each q-space location and an image of velocity components for each q-space location; and producing a three-dimensional velocity image from the image of the velocity components.

Abstract: A signal processing method is provided. The signal processing method includes the steps of generating undersampled data corresponding to an object, determining a variable thresholding parameter based on a composition of the undersampled data, and iteratively determining thresholded coefficients to generate a plurality of coefficients by utilizing the undersampled data, a current solution and the variable thresholding parameter by updating the variable thresholding parameter and the current solution, and reconstructing a data signal using the plurality of coefficients.

Abstract: Systems and methods for generating a magnetic resonance (MR) image of a tissue are provided. A method includes acquiring MR raw data. The MR raw data corresponds to MR signals obtained at undersampled q-space locations for a plurality of q-space locations that is less than an entirety of the q-space locations and the MR signals at the q-space locations represent the three dimensional displacement distribution of the spins in the imaging voxel. The method also includes performing a joint image reconstruction technique on the MR raw data to exploit structural correlations in the MR signals to obtain a series of accelerated MR images and performing, for each image pixel in each accelerated MR image of the series of accelerated MR images, a compressed sensing reconstruction technique to exploit q-space signal sparsity to identify a plurality of diffusion maps.

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: A system and method is disclosed for tracking a moving object using magnetic resonance imaging. The technique includes acquiring a scout image scan having a number of image frames and extracting non-linear motion parameters from the number of image frames of the scout image scan. The technique includes prospectively shifting slice location using the non-linear motion parameters between slice locations while acquiring a series of MR images. The system and method are particularly useful in tracking coronary artery movement during the cardiac cycle to acquire the non-linear components of coronary artery movement during a diastolic portion of the R-R interval.

Abstract: A system for inductively communicating signals in a magnetic resonance imaging system is presented. The system includes first array of primary coils configured to acquire data from a patient positioned on a patient cradle. Furthermore, the system includes a second array of secondary coils operatively coupled to the first array of primary coils. Moreover, the system includes a third array of tertiary coils disposed at a determined distance from the second array of secondary coils. In addition, the system includes a tuning unit operatively coupled to the third array of tertiary coils by a cable having a quarter-wave electrical wavelength and configured to control the first array of primary coils through impedance transformation, where the second array of secondary coils is configured to inductively communicate the acquired data to the third array of tertiary coils.

Abstract: Exemplary embodiments of the present disclosure are directed to correcting lung density variations in positron emission tomography (PET) images of a subject using a magnetic resonance (MR) image. A pulmonary vasculature and an outer extent of a lung cavity can be identified in a MR image corresponding to a thoracic region of the subject in response to an intensity associated with pixels in the MR image. The pixels within the outer extent of the lung cavity are classified as corresponding to the pulmonary vasculature or the lung tissue. Exemplary embodiments of the present disclosure can apply attenuation coefficients to a reconstruction of the PET image based on the classification of the pixels within the outer extent of the lung cavity.

Abstract: Exemplary embodiments are directed to acquiring multiple sets of positron emission tomography (PET) data for different areas of a subject concurrently with acquiring portions of a single magnetic resonance field of view. Positron emission tomography (PET) images and magnetic resonance (MR) images can be acquired using a combined PET-MRI scanner, wherein, for example, a first portion of MR data from a MR field of view can be acquired concurrently with a first acquisition of PET data, a position of the MR field of view can be adjusted in response to a change in a location of a bed in the combined PET-MRI scanner, and a second portion of MR data from the MR field of view can be acquired concurrently with a second acquisition of PET data.

Abstract: An imaging system is presented. The imaging system includes a cradle, and a first sheet of coils disposed inside of the cradle such that a first end of the first sheet of coils protrudes out of the cradle and a second end of the first sheet of coils is coupled to a structure, wherein a requisite expanse of the first sheet of coils is flexibly pulled out from the cradle by pulling the first end.

Abstract: An imaging system is presented. The imaging system includes a storage structure that stores a first sheet of coils inside a cradle, wherein the storage structure includes a plurality of first set of rotatable bodies and a plurality of second set of rotatable bodies, and a plurality of springs that are coupled to one or more of the plurality of second set of rotatable bodies, wherein the first sheet of coils is disposed around the plurality of first set of rotatable bodies, the plurality of second set of rotatable bodies and the plurality of springs, and wherein a first end of the first sheet of coils protrudes out of the cradle.