Beth Israel Deaconess Medical Center, Inc.

University of Pennsylvania

General Electric Company

David C Alsop

Li Zhao

Ananth J Madhuranthakam

Gopal Varma

Aaron K Grant

Huanzhou Yu

Elena Vinogradov

Robert E Lenkinski

Manuel Taso

Rachel Scheidegger

Neil M Rofsky

Systems and methods are provided for producing an image of a subject using a magnetic resonance imaging (MRI) system. The method includes designing a saturation-based labeling pulse sequence for an MRI process that includes radio-frequency (RF) pulses and gradients forming a ratio of RF slice-selection gradient to time-averaged gradient that maintains multiple aliased labeling planes within an envelope of the RF pulses. The method also includes performing the MRI process to acquire image data from the subject using the saturation-based labeling pulse sequence and reconstructing a saturation-based spin labeled images of the subject using image data.

Systems and methods for spin labeling in magnetic resonance imaging

Systems and methods are provided for producing hyperpolarized materials for use during a magnetic resonance imaging (MRI) or nuclear magnetic resonance (NMR) process. The system and methods include the use of microfluidic and/or microreactor methods in one or more of the stages of parahydrogen production, enriched substrate production, and spin order transfer from the parahydrogen to a substrate.

System and method for microfluidic parahydrogen induced polarization hyperpolarizer for magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) applications

Systems and methods for acquiring magnetic resonance imaging (MRI) images of a subject are provided. The method includes performing a pulse sequence to elicit spin echoes, wherein the pulse sequence includes a radio frequency (RF) excitation pulse and a series of RF refocusing pulses that refocus echoes with flip angles in the series of RF refocusing pulses that are varied. The method also includes scaling MRI data associated with each echo by a correction factor that is determined for each echo to create scaled MRI data and that is not the same for all echoes. The method then includes reconstructing an image of the subject using the scaled MRI data.

System and method for improved spin-echo-based magnetic resonance imaging

A magnetic resonance imaging (MRI) system is provided that is controlled by a computer. The computer is programmed to control a plurality of gradient coils and radio frequency (RF) system of the MRI system to perform at least one pulse sequence that includes applying RF energy at least at two frequencies to manipulate exchangeable magnetization from protons in a subject. The computer is also programmed to control the plurality of gradient coils and RF system to acquire imaging data including magnetization transfer information from the exchangeable magnetization from protons in the subject in response to the pulse sequence. The computer is further programmed to, using frequency information associated with the imaging data, generate a report pertaining to inhomogeneous magnetization transfer occurring in the subject in response to the pulse sequence.

System and method for inhomogeneous magnetization transfer magnetic resonance imaging

A system and methods for improved homogeneous and inhomegeneous magnetic transfer imaging are provided. In some aspects, a plurality of gradient coils and an RF system of a magnetic resonance imaging ('MRI') system are controlled, using a computer, to perform, at least one pulse sequence that includes a preparation module followed by an imaging module, wherein the preparation module comprises a plurality of radio frequency ('RF') saturation pulses applied according to a concentrated pulse cycle to manipulate exchangeable magnetization from protons in the subject, and the imaging module is configured to acquire image data. The computer is also configured to analyze the image data acquired to generate frequency information indicative of the exchangeable magnetization from protons in the subject, and generate a report, using the frequency information, pertaining to inhomogeneous or homogeneous magnetization transfer occurring in the subject.

System and method for improved homogeneous and inhomogeneous magnetization transfer magnetic resonance imaging

Systems and methods for generating a medical image of a subject that includes functional information. First, two medical images are acquired. One is weighted based on functional information reflecting physiological functions of the subject and the other weighted based on anatomic information of the subject. A difference image between the two images are generated. By subjecting the difference image and the second image to a localized kernel, a local similarity image is generated. Using the local similarity image, an improved difference image is generated. Lastly, by subtracting the improved difference image from the first image, an enhanced medical image that retains the functional information reflecting physiological functions of the subject is generated.

System and method for enhancing functional medical images

A system and method for producing a report about a subject from data collected from the subject using a magnetic resonance imaging (MRI] system. The method includes directing the MRI system to perform a pulse sequence to manipulate exchangeable magnetization in the subject and acquiring, with the MRI system, imaging data from the subject in response to the pulse sequence. The method also includes analyzing the effects of the frequencies of applied RF energy on the imaging data to identify inhomogeneous lines formed by a summation of multiple sublines centered at multiple different frequencies. The method further includes generating a report pertaining to inhomogeneous magnetization transfer occurring in the subject in response to the pulse sequence.

System and method for magnetic resonance imaging using exchange time reflective of motion restriction or spin diffusion of protons bound to macromolecules

A method for chemical exchange saturation transfer ('CEST') imaging that is more insensitive to off-resonance and magnetization transfer effects than other CEST methods is provided. Sn general, three different images are obtained: one obtained with radio frequency ('RF') saturation about a labeling frequency, one obtained with RF saturation about a reference frequency, and one obtained with RF saturation about both the labeling and reference frequencies. This method, termed saturation with frequency alternating radiofrequency irradiation (&#x201c;SAFARI&#x201d;), is also very robust to magnetic field inhomogeneities. The three images, referred to as a labeled image, reference image, and dual frequency image, are selectively combined to produce an image of the subject in which CEST contrast is present, but errors arising from off-resonance and magnetization transfer effects are substantially suppressed.

Method for measuring magnetization transfer between molecules with magnetic resonance imaging

A system and method for double inversion recovery for reduction of T1 contribution to fluid-attenuated inversion recovery imaging include a computer programmed to prepare a double inversion recovery (DIR) sequence comprising a pair of inversion pulses and an excitation pulse, execute the DIR sequence to acquire MR data from an imaging subject, and reconstruct an image based on the acquired MR data. The preparation of the DIR sequence comprises optimizing a first inversion time (TI) between the pair of inversion pulses and a second inversion time (TI) between one of the pair of inversion pulses and the excitation pulse to cause a first tissue of the imaging subject to be suppressed in the image and to reduce a T1 contrast between a second tissue and a third tissue of the imaging subject in the image.

[object Object]

An MRI apparatus is disclosed, the MRI apparatus comprising a computer programmed to apply a fluid suppression technique prior to an imaging pulse-gradient sequence, wherein the fluid suppression technique is configured to suppress signals from fluids having long longitudinal relaxation times, and apply a fat suppression technique after the fluid suppression technique and prior to the imaging pulse-gradient sequence, wherein the fat suppression technique is configured to suppress fat signals. The computer is further programmed to apply a flow suppression preparation sequence after the fat suppression technique and prior to the imaging pulse-gradient sequence, wherein the flow suppression preparation sequence is configured to suppress moving tissue signals. The computer is also programmed to apply the imaging pulse-gradient sequence, cause the RF transceiver system to acquire MR signals during the imaging pulse-gradient sequence, and reconstruct an image from the acquired MR signals.

System and method of high signal-to-noise ratio magnetic resonance imaging screening

In one aspect, a method of imaging blood flow in a region of interest of a subject using magnetic resonance imaging (MRI) is provided. The method includes introducing an imaging agent into the subject, the imaging agent including a compound having at least one hyperpolarized nucleus having a T.sub.1 greater than 15 seconds and a water-octanol partition coefficient between &#x2212;1 and 1, providing at least one excitation signal to the region of interest, the at least one excitation signal configured to invoke a nuclear magnetic resonance (NMR) effect at least in the introduced imaging agent, and detecting an NMR signal emitted by the region of interest in response to the at least one excitation signal. In another aspect, the imaging agent includes a carbon-13 enriched alcohol.

Imaging agents for use in magnetic resonance blood flow/perfusion imaging

An apparatus and method for separating the NMR signal contributions from a plurality of different species having different chemical shifts is disclosed. The apparatus acquires MR image data sets including a first species signal and a second species signal, generates a first species image from the acquired MR image data, and generates a second species image from the acquired MR image data. The apparatus also identifies voxels in the second species image representative of only the second species and, for voxels identified as being representative of only the second species, calculates a fraction of the second species signal appearing in the first species image. The apparatus generates a modified first species image based on the fraction of the second species signal appearing in the first species image, with the modified first species image having a different fraction of the second species as compared to the first species image.

System and method for fat suppression in chemical shift based water-fat separated MR imaging

This invention is a method for multi-slice CBF imaging using continuous arterial spin labeling (CASL) with an amplitude modulated control which is both highly effective at controlling for off resonance effects, and efficient at doubly inverting inflow spins, thus retaining the signal advantages of CASL versus pulsed ASL techniques.

Multi-slice cerebral blood flow imaging with continuous arterial spin labeling MRI

In one aspect, a method for imaging fluid flow and/or perfusion using spin labeling is provided. The method comprises applying a first magnetic gradient sequence at least to a labeling region, applying a first pulsed radio frequency (RF) sequence to the labeling region to label the fluid, the first pulsed RF sequence comprising a first plurality of pulses wherein an amplitude envelope is non-zero, the first plurality of pulses each separated by a respective first plurality of intervals wherein the amplitude envelope is substantially zero, and acquiring at least one first signal emitted from an imaging region a predetermined delay after applying the first pulsed RF sequence.

Growing community of inventors

Boston, MA, United States of America

David C Alsop