Abstract: The disclosed embodiments provide a method for acquiring MR data at resolutions down to tens of microns for application in in vivo diagnosis and monitoring of pathology for which changes in fine tissue textures can be used as markers of disease onset and progression. Bone diseases, tumors, neurologic diseases, and diseases involving fibrotic growth and/or destruction are all target pathologies. Further the technique can be used in any biologic or physical system for which very high-resolution characterization of fine scale morphology is needed. The method provides rapid acquisition of signal at selected values in k-space, with multiple successive acquisitions at individual k-values taken on a time scale on the order of microseconds, within a defined tissue volume, and subsequent combination of the multiple measurements in such a way as to maximize SNR.
Abstract: A method for selective sampling to assess texture of a specimen using magnetic resonance (MR) excites the specimen and refocuses to provide a sample rod within the specimen. An encoding gradient pulse is applied to induce phase wrap creating a spatial encode for a specific k-value and orientation. A low non-zero magnitude gradient is then applied acting as a time dependent phase encode to produce a time varying trajectory through 3D k-space of k-value encodes while simultaneously recording multiple sequential samples of the signal at a sequence of k-values proximate the specific k-value. The receiver bandwidth is set to delineate a length of a VOI within the rod during the data sampling. The samples are then post processed at the sequence of k values, recorded within a time span while the non-zero magnitude gradient is applied, to characterize the textural features of tissue in the VOI.
Abstract: The disclosed embodiments provide a method for acquiring MR data at resolutions down to tens of microns for application in in vivo diagnosis and monitoring of pathology for which changes in fine tissue textures can be used as markers of disease onset and progression. Bone diseases, tumors, neurologic diseases, and diseases involving fibrotic growth and/or destruction are all target pathologies. Further the technique can be used in any biologic or physical system for which very high-resolution characterization of fine scale morphology is needed. The method provides rapid acquisition of signal at selected values in k-space, with multiple successive acquisitions at individual k-values taken on a time scale on the order of microseconds, within a defined tissue volume, and subsequent combination of the multiple measurements in such a way as to maximize SNR.
Abstract: A method for identifying the chemical species of various textural elements in a targeted region of tissue wherein a volume of interest (VOI) is selectively excited and a k-encode gradient pulse is applied to induce phase wrap to create a spatial encode for a specific k-value and orientation. The specific k-value is selected based on anticipated texture within the VOI. Multiple sequential samples of the NMR RF signal encoded with the specific k-value are recorded as signal data. The Fourier Transform of the acquired signal data is then taken, wherein for each k-encode, the signal recorded is indicative of the spatial frequency power density at that point in k-space. Each peak in the NMR spectrum is then evaluated, whereby the relative contribution to the texture of tissue in the VOI at a k-value for each chemical species is determined.
Type:
Grant
Filed:
July 6, 2018
Date of Patent:
February 26, 2019
Assignee:
BIOPROTONICS INC.
Inventors:
Ian Parker, David R. Chase, Timothy W. James, Kristin James