Abstract: Described herein are systems and methods for quantitatively measuring manganese ion efflux in a subject. In general, the systems and methods compare imaging data from a subject taken over specific periods of time to pharmacokinetic models in order to measure manganese ion efflux rates from an organ in a subject. By understanding the specific location and rate of manganese ion efflux and influx from the organ, it is possible to more accurately correlate calcium ion activity. Calcium ion efflux is associated with a number of biological mechanisms in the subject, and the methods and systems described herein can be used as a diagnostic tool not only for monitoring calcium efflux in the subject but also aid in the treatment of diseases associated with changes in calcium ion efflux.

Abstract: Described herein are systems and methods for quantitatively measuring manganese ion efflux in a subject. In general, the systems and methods compare imaging data from a subject taken over specific periods of time to pharmacokinetic models in order to measure manganese ion efflux rates from an organ in a subject. By understanding the specific location and rate of manganese ion efflux and influx from the organ, it is possible to more accurately correlate calcium ion activity. Calcium ion efflux is associated with a number of biological mechanisms in the subject, and the methods and systems described herein can be used as a diagnostic tool not only for monitoring calcium efflux in the subject but also aid in the treatment of diseases associated with changes in calcium ion efflux.

Abstract: A method for synthesizing crossing ADC distributions via reassembly of multiple k-spaces is disclosed. The method includes the steps of scanning a test object having a plurality of anisotropic structures to acquire a first set of DTI data using gradient directions; rotating the gradient directions by an angle ?; repeating the step of scanning the test object to acquire a second set of DTI data; creating a composite data set from the first and second sets of data; and applying an inverse Fourier transform to the composite data set.

Abstract: A test object for use with diffusion MRI and a system and methods of synthesizing complex diffusive geometries. The test object, which includes anisotropic structures, can be used to monitor DTI measures by providing a baseline measurement. Using measurements of the phantom, data characteristic of more complicated diffusive behavior can be “synthesized”, or composed of actual measurements re-arranged into a desired spatial distribution function describing diffusion. Unlike a typical DTI scan, the ADC measurements of the present invention are treated in a “reconstruction” phase as if the gradients were applied in different directions. Given a set of reconstruction directions, a judicious choice of acquisition directions for each reconstruction direction allows for the synthesis of any distribution.

Abstract: A system and method for minimizing, if not completely eliminating, the systematic bias present in an MR system used for DTI is disclosed. A test object or “phantom” of the present invention is scanned with a desired DTI protocol. The eigenvalues measured with the phantom are compared to the actual values that should have been measured, and a parametric map that links measured eigenvalues to actual eigenvalues is calculated, which is applicable to the desired protocol. Future eigenvalue measurements using this protocol can be recalibrated to actual eigenvalues using this map.

Abstract: A method for scaling MR signal intensity after noise has been removed is disclosed. Because the signal in a DTI series varies with the apparent diffusivity in the direction of an applied gradient, one can multiply image data collected under actual clinical conditions with a spatially-dependent scaling function to synthesize different spatial diffusion distributions, after removal of noise. Recombination of the data with the removed noise preserves the bias in the system.

Abstract: A method for synthesizing crossing ADC distributions via reassembly of multiple k-spaces is disclosed. The method includes the steps of scanning a test object having a plurality of anisotropic structures to acquire a first set of DTI data using gradient directions; rotating the gradient directions by an angle ?; repeating the step of scanning the test object to acquire a second set of DTI data; creating a composite data set from the first and second sets of data; and applying an inverse Fourier transform to the composite data set.

Abstract: A system and method for minimizing, if not completely eliminating, the systematic bias present in an MR system used for DTI is disclosed. A test object or “phantom” of the present invention is scanned with a desired DTI protocol. The eigenvalues measured with the phantom are compared to the actual values that should have been measured, and a parametric map that links measured eigenvalues to actual eigenvalues is calculated, which is applicable to the desired protocol. Future eigenvalue measurements using this protocol can be recalibrated to actual eigenvalues using this map.

Abstract: A method for scaling MR signal intensity after noise has been removed is disclosed. Because the signal in a DTI series varies with the apparent diffusivity in the direction of an applied gradient, one can multiply image data collected under actual clinical conditions with a spatially-dependent scaling function to synthesize different spatial diffusion distributions, after removal of noise. Recombination of the data with the removed noise preserves the bias in the system.

Abstract: A test object for use with diffusion MRI and a system and methods of synthesizing complex diffusive geometries. The test object, which includes anisotropic structures, can be used to monitor DTI measures by providing a baseline measurement. Using measurements of the phantom, data characteristic of more complicated diffusive behavior can be “synthesized”, or composed of actual measurements re-arranged into a desired spatial distribution function describing diffusion. Unlike a typical DTI scan, the ADC measurements of the present invention are treated in a “reconstruction” phase as if the gradients were applied in different directions. Given a set of reconstruction directions, a judicious choice of acquisition directions for each reconstruction direction allows for the synthesis of any distribution.