Mayo Foundation for Medical Education and Research

General Electric Company

Siemens Healthcare Gmbh

Joel P Felmlee

Richard L Ehman

Kiaran P McGee

Armando Manduca

Vibhas S Deshpande

Phillip J Rossman

Josef P Debbins

Bradley J Erickson

Peter Kollasch

Venkata Veerendranadh Chebrolu

John William Grinstead

Matthew C Murphy

Russell Edward Bruhnke

Kimberly K Amrami

Ramesh Avula

William Ryan

Brian C Goss

James P Potter, Sr

Stephanie K Carlson

Tao Wu

Matthew A Frick

Systems and methods for generating images with a magnetic resonance imaging ('MRI') system, in which the images have been corrected for receive coil nonuniformities are described. Improved data acquisition schemes for fat saturation are also described.

Method for uniform reconstruction of multi-channel surface-coil magnetic resonance data without use of a reference scan

A magnetic resonance imaging receiver coil provides for high SNR and high uniformity over a range of loading conditions with layers, or stacks, of independent conductive elements. The plurality of layers preload the receiver coil reducing the circuit variation as the subject coupling and loading varies. The preload is such that coil performance, or SNR, is maintained over a large range of impedance variation. This configuration is designed to exceed the performance of single trace coils over a range of impedance consistent with variations associated with different subjects, and may also incorporate coils of different resonance frequencies.

Spatially coincident MRI receiver coils and method for manufacturing

A system and method for generating a magnetic resonance elastography (MRE) report includes a) acquiring MRE data from a subject including positively motion encoded medical imaging data and negatively motion encoded medical imaging data and b) deriving uncorrected difference medical imaging data from the MRE data for a given slice. The method also includes c) filtering the uncorrected difference medical imaging data to create filtered medical imaging data corrected for errors associated with phase ramps occurring during gradient switching used to derive the positively motion encoded medical imaging data and negatively motion encoded medical imaging data, d) generating a corrected difference image for the given slice from the filtered medical imaging data and the uncorrected difference medical imaging data, e) repeating steps b) through d) for each slice reflected in the MRE data, and f) generating a report of elastic properties of the subject from the corrected difference image.

System and method for improved efficiency in magnetic resonance elastography

A noble gas is administered to a subject to fill the lungs and magnetic resonance elastography image data is acquired while vibrations are applied to the chest wall. Shear waves are established in the gas-filled lungs by the vibrations and a shear modulus image is reconstructed from the MRE image data that may be used in the diagnosis of lung disease.

Imaging elastic properties of the lung with magnetic resonance elastography

A bellows-based patient breath-hold monitoring and feedback system for use in intermittent mode CT fluoroscopy-guided biopsies of the lung or upper abdomen where respiratory motion is a problem. Breath-hold monitoring and feedback with the bellows system allows a patient to perform consistent breath-holds at a preselected level, which in turn, optimizes intermittent mode CT fluoroscopy-guided biopsies of the lung or upper abdomen by allowing target lesions to be reliably visualized.

Motion monitor system for use with imaging systems

An MRI system is employed to aim an ultrasonic transducer at tissues to be treated and to produce images which enable the treatment of the tissues to be monitored. A pulse sequence is used which produces both a spin-echo NMR signal and a gradient-echo NMR signal and changes in phase between these two signals is measured and used to produce a temperature map. Changes in amplitude of the spin-echo NMR signal from a reference spin-echo NMR signal is used to produce images which indicate temperature changes in both fat and water. These temperature maps may be used to aim the heat treatment device.

MR-guided breast tumor ablation and temperature imaging system

Two magnetic resonance images are acquired of seeds used in brachytherapy of the prostate with different pulse sequences. Phase images and magnitude images are reconstructed and a phase difference image is calculated and combined with the magnitude images. The magnitude images differentiate soft tissues and the phase difference image differentiates the locations of the seeds.

Magnetic resonance imaging of prostate brachytherapy seeds

An MRA image is corrected for motion artifacts using an iterative, autocorrection process in which corrections are tried and the quality of the resulting reconstructed image is measured. Corrections are made to the acquired three-dimensional data while the metric which measures image quality is applied to a two-dimensional projection image.

Autocorrection of MR projection images

An MRI image acquired with a phase-array coil is corrected for motion artifacts using an iterative, autocorrection process in which corrections are tried and the quality of the resulting reconstructed image is measured. In one embodiment autocorrections are calculated for the data acquired with one coil element and the same corrections are made to data acquired with the other coil elements. In another embodiment autocorrections are calculated separately for the data acquired with each coil element. In either embodiment, the separate corrected images are combined to form the output image.

Autocorrection of MR images acquired using phased-array coils

A three-dimensional image data set is acquired with an MRI system and autocorrected to reduce artifacts caused by subject motion during image acquisition. Correction for motion along one or two axes is performed by selecting a 2D slice of data and autocorrecting it to produce phase corrections that are then made to the entire 3D image data set. This may be repeated by autocorrecting an additional 2D slice perpendicular to the first 2D slice to produce phase corrections for the 3D image data set for motion along the third axis.

Autocorrection of 3D MR images for motion artifacts

An MRI image is corrected for motion artifacts using an iterative, autocorrection process in which corrections are tried and the quality of the resulting reconstructed image is measured. Different metrics for evaluating image quality are used during the autocorrection process to take advantage of their different attributes.

Autocorrection of MR images using multiple metrics

Navigator echo signals are acquired during an MRI scan in which image data is acquired. The navigator echo signals are used to estimate an initial correction of the acquired image data for patient motion during the scan. The initially corrected image data is then autocorrected in an iterative process which measures image quality and makes further corrections to the image data until the measured image quality is within tolerance.

Correction of MR images for motion artifacts using navigator echoes and autocorrection

Devices for producing an oscillatory shear stress within an object positioned in a polarizing magnetic field of an NMR imaging system are used to perform MR elastography. In one embodiment shear stress is produced within the brain by vibrating the entire skull with a transducer that is gripped by the patient's teeth.

Inertial driver device for MR elastography

An MRI system acquires NMR data and reconstructs an image. The image is enhanced prior to being displayed by automatically calculating a window level value and a window width value and mapping the reconstructed image through the resulting contrast window defined by those values.

Automatic windowing method for MR images

An MRI system employs a multicoil array to acquire NMR data. A calibration scan is performed and a phase map is produced for each coil element in the array. A region of interest in the field of view is identified and corresponding phase values are extracted from each phase map and used to correct the phase of the k-space NMR data set acquired by each coil element in subsequent image scans. The corrected k-space NMR data sets for the coil elements are combined into a single k-space NMR data set to enable an image to be reconstructed therefrom by Fourier transformation.

Growing community of inventors

Rochester, MN, United States of America

Joel P Felmlee