University of Southern California

Richard M Leahy

Quanzheng Li

Wentao Zhu

Peter Conti

Justin P Haldar

Bing Bai

Sanghee Cho

Sangtae Ahn

A medical imaging system for reconstructing quantitative dynamic nuclear medicine images of a subject may include a three dimensional positron emission tomography (3D PET) scanner and a data processing system. The three dimensional positron emission tomography (3D PET) scanner may: perform scans of the subject at each of multiple bed positions, each scan being of only a sub-portion of the subject that is within an axial length covered by the scanner; and generate dynamic list-mode PET data that: represents a total number of photon pairs arriving at each of multiple detector pairs in the 3D PET scanner; and is organized in a list of elements, each element in the list including a detector pair index and an arrival time for each detected photon pair; and acquires PET data using a dynamic PET protocol with at least two scans at each of the multiple bed positions. The data processing system may: reconstruct Patlak slope and intercept images of the subject over an axial length of the subject that exceeds the axial length of each scan of the subject by optimizing a likelihood or penalized likelihood function using the list-mode PET data from at least two scans of the subject at each of the multiple bed positions; and store the reconstructed image in a storage device or displays the reconstructed image on a display system.

Direct patlak estimation from list-mode PET data

Samples of a Fourier transform of a signal may be received that are distributed in a generally spherically-shaped pattern on a surface of at least one sphere. The samples may be assembled to form a profile function having a domain that is a surface of at least one sphere. Information indicative of at least one property of the signal may be determined by applying a spherical linear transform to the profile function. The spherical linear transform may use more than just an equator of the profile function for each of multiple orientations.

Linear transform for diffusion MRI

A technique for processing of data from time-of-flight (TOF) PET scanners. The size of TOF PET data may be reduced without significant loss of information through a process called rebinning. The rebinning may use the Fourier transform properties of the measured PET data, taken with respect to the time-of-flight variable, to perform data reduction. Through this rebinning process, TOF PET data may be converted to any of the following reduced representations: 2D TOF PET data, 3D non-TOF PET data, and 2D non-TOF PET data. Mappings may be exact or approximate. Approximate mappings may not require a Fourier transform in the axial direction which may have advantages when used with PET scanners of limited axial extent. Once TOF PET data is reduced in size using this rebinning, PET images may be reconstructed with hardware and/or software that is substantially less complex and that may run substantially faster in comparison to reconstruction from the original non-rebinned data.

Exact and approximate rebinning of time-of-flight PET positron emission tomography data

Growing community of inventors

El Segundo, CA, United States of America

Richard M Leahy