The General Hospital Corporation

Ouri Cohen

Matthew Scot Rosen

Mathieu Sarracanie

Bo Zhu

Christian T Farrar

Shuning Huang

Lionel Broche

Disclosed is a system and method for estimating quantitative parameters of a subject using a magnetic resonance ('MR') system using a dictionary. The dictionary may include a plurality of signal templates that sparsely sample acquisition parameters used when acquiring data. The acquired data is compared with the dictionary using a neural network. Thus, systems and methods are provided that are more computationally efficient, and have reduced data storage requirements than traditional MRF reconstruction systems and methods.

System and method for magnetic resonance fingerprinting using neural networks trained with sparsely sampled dictionaries

A system and method of use includes (a) directing a magnetic resonance (MR) system to perform a pulse sequences block in which radio frequency (RF) energy is applied to the subject to substantially saturate magnetization corresponding to an exchangeable proton. The method includes (b), following step (a), acquiring data from the subject with the MR system and (c) repeating step (a) a plurality of times where parameters of the pulse sequence sub-block differ in at least some pulse sequence sub-blocks by at least an amount of RF energy applied to saturate the magnetization. The method further includes (d), after each repetition of step (a), repeating step (b) to acquire data representing signal evolutions from the subject. Additionally, the method includes (e) comparing the signal evolutions with a dictionary database comprising a plurality of different signal evolution templates to determine quantitative chemical exchange or exchangeable proton information of the subject.

System and method for chemical exchange saturation transfer (CEST) magnetic resonance fingerprinting

Provided is a system and method for performing a magnetic resonance fingerprinting imaging process. The process includes determining acquisition parameters including at least one of repetition time (TR) or flip angle (FA), selected to control one of a duration and a number of repetitions of for a pulse sequence that samples k-space in a Cartesian acquisition pattern by acquiring an echo train. The process also includes controlling a magnetic resonance imaging (MRI) system to perform the pulse sequence a plurality of times to acquire magnetic resonance fingerprinting (MRF) data corresponding to signals from the subject excited by the pulse sequence. The process also includes estimating quantitative tissue properties of the subject by comparing the MRF data to a database and reconstructing, from the MRF data, at least one image of the subject indicating the estimated quantitative tissue properties.

3D balanced EPI magnetic resonance fingerprinting

A system and method is provided for estimating quantitative parameters of a subject using a magnetic resonance system. The method includes using a neural network, estimating acquisition parameters that are selected to direct a magnetic resonance system to generate a plurality of different signal evolutions that elicit discrimination between different quantitative parameters in a desired number of repetition time (TR) periods. The method also includes acquiring data with the magnetic resonance system by performing a plurality of pulse sequences using the estimated acquisition parameters, where the acquired data representing the plurality of different signal evolutions that elicit discrimination between different quantitative parameters. The method further includes estimating quantitative parameters of the subject by comparing the acquired data with a dictionary database comprising a plurality of different signal templates and generating a report indicating the quantitative parameters.

Systems and methods for efficient magnetic resonance fingerprinting scheduling

Systems and methods for estimating quantitative parameters of a subject from data acquired using a magnetic resonance imaging (MRI) system. MR data acquired with an MRI system is provided, which represents a plurality of different signal evolutions acquired using different acquisition parameter settings. An initial dictionary comprising a plurality of signal templates is generated that coarsely sample acquisition parameters used when acquiring the provided MR data. The MR data is compared with the initial dictionary. The quantitative parameters associated with an entry in the initial dictionary are stored as the estimated quantitative parameters when the comparison satisfies a threshold criterion and the initial dictionary is updated when the comparison does not satisfy the threshold criterion.

System and method for adaptive dictionary matching in magnetic resonance fingerprinting

Systems and methods for multislice magnetic resonance fingerprinting ('MRF') are provided. Data are acquired from multiple different slices, either simultaneously or sequentially, using a schedule of acquisition parameters that are optimized or otherwise selected for each different slice. Dictionary matching techniques are then used to estimate quantitative parameters from the acquired data. The methods can provide both in-plane and through-plane acceleration without the use of multi-channel radio frequency coils.

Systems and methods for multislice magetic resonance fingerprinting

Systems and methods for acquiring magnetic resonance fingerprinting (MRF) data includes performing a schedule optimization that sequentially selects discrimination at each trajectory to yield an optimal trajectory and controlling a magnetic resonance imaging (MRI) system to perform a pulse sequence using the optimal trajectory to acquire MRF data. The process also includes estimating quantitative parameters of the subject using the MRF data by comparing the MRF data to a dictionary database and generating a map of quantitative parameters of the subject using the estimated quantitative parameters of the subject and the MRF data.

Systems and methods for efficient trajectory optimization in magnetic resonance fingerprinting

Described here are systems and methods for generating quantitative perfusion parameter maps based on different longitudinal relaxation parameter maps that are produced from images acquired using non-selective and selective magnetic resonance imaging ('MRI') data acquisition techniques.

Rapid measurement of perfusion using optimized magnetic resonance fingerprinting

Quantitative perfusion parameter maps can be generated based on multiple different relaxation parameter maps that are simultaneously produced from images acquired using contrast-enhanced magnetic resonance imaging ('MRI') techniques.

Simultaneous dynamic contrast enhanced and dynamic susceptibility magnetic resonance imaging using magnetic resonance fingerprinting

Systems and methods for accelerating magnetic resonance fingerprinting ('MRF') acquisitions are described. The method includes controlling the MRI system to acquire magnetic resonance fingerprinting (MRF) data from the subject by performing a gradient-echo pulse sequence. The pulse sequence includes maintaining residual transverse magnetization through a delay period performed between successive cycles of the pulse sequence. The delay period is selected to allow spins of different tissue types within the subject to evolve differently as a function of tissue parameters within the different tissue types during the delay period.

Systems and methods for steady-state magnetic resonance fingerprinting

Systems and methods for magnetic resonance fingerprinting ('MRF') using highly differentiated trajectories that optimize differentiation between magnetic resonance signal patterns as a function of relaxation time(s) and static magnetic field homogeneity are described. Using the optimized acquisition parameters, MRF can be performed in the presence of inhomogeneous magnetic fields. Flip angle homogeneity can also be incorporated into the dictionary matching process to simultaneously estimate quantitative parameters of the subject and radio frequency coil transmission homogeneity profiles.

System and method for magnetic resonance fingerprinting in the presence of inhomogeneous magnetic fields

Systems and methods for accelerating magnetic resonance fingerprinting ('MRF'} acquisitions are described. Acquisition parameters can be optimized to reduce the number of acquisitions necessary while maximizing the discrimination between the physical parameters to be estimated. The systems and methods may also include implementing pulse sequences that rapidly acquire large volumes of k-space data, including echo-planar imaging ('EPI'} and segmented EPI sequences.

Systems and methods for acceleration magnetic resonance fingerprinting

Systems and methods for estimating quantitative parameters of a subject from data acquired using a magnetic resonance imaging (MRI) system. The system includes a computer system configured to control the MRI system to acquire MR fingerprinting (MRF) data representing a plurality of different signal evolutions acquired using different acquisition parameter settings and reconstruct the MRF data into at least one image composed of a plurality of pixels or voxels formed of multiple compartments per pixel or voxel. The computer system is further configured to, on a compartment-by-compartment basis, compare a signal associated with each compartment to an initial dictionary comprising a plurality of signal templates that coarsely sample different acquisition parameters used to acquire the MRF data to determine quantitative parameters for each compartment. The computer system is further configured to generate a quantitative parameter map that indicates the quantitative parameters for each compartment.

System and method for controlling partial volume effects in magnetic resonance fingerprinting

Systems and methods for producing a quantitative parameter map using a magnetic resonance imaging (MRI) system includes providing magnetic resonance fingerprinting (MRF) data acquired with an MRI system from a subject. The MRF data represents a plurality of different signal evolutions acquired using different acquisition parameter settings. The method also includes providing a database comprising a plurality of sub-dictionaries, each sub-dictionary including a plurality of signal templates, sequentially comparing the MRF data to each of the sub-dictionaries to estimate quantitative parameters, and generating a quantitative parameter map of the subject using the estimate quantitative parameters.

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Teaneck, NJ, United States of America

Ouri Cohen