Abstract: 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.

Abstract: The present disclosure addresses the challenges of in vivo phosphorus imaging by providing a clinically useful phosphorus MRI (PMRI) system and method that may be performed on a standard MRI system in a clinically reasonable scan time using specifically tuned coils, a phosphorus pulse sequence, and improved reconstruction and post processing algorithms.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A system and method for analyzing a subject using a magnetic resonance imaging (MRI) system is provided. The technique includes positioning a subject within the MRI system and coupling a driver to the subject to impart vibrational energy to the subject. The technique further includes using the MRI system and in coordination with operation of the driver, acquiring medical imaging data from the subject's brain and deriving stiffness information of the subject's brain from the medical imaging data. A report, such as an image, can be provided indicating the stiffness information of the subject's brain relative to baseline stiffness information to indicate a status of the subject with respect to a neurodegenerative disease.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Motion artifacts are selectively suppressed in an image by correcting only the NMR data in the central views. The peripheral views are not corrected with the result that motion artifacts produced by large objects in the image are suppressed while motion artifacts produced by small objects are not. Consequently, the interior of small blood vessels remain darker in the reconstructed image.