Devices, Systems and Methods Utilizing Framelet-Based Iterative Maximum-Likelihood Reconstruction Algorithms in Spectral CT
AssigneeUniversity of Iowa Research Foundation
InventorsWenxiang Cong, Ye Yangbo, Ge Wang, Shuwei Mao, Yingmei Wang
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Abstract
The disclosed apparatus, systems and methods relate to a framelet-based iterative algorithm for polychromatic CT which can reconstruct two components using a single scan. The algorithm can have various steps including a scaled-gradient descent step of constant or variant step sizes; a non-negativity step; a soft thresholding step; and a color reconstruction step.
Claims20
(canceled)
The system of claim 8, wherein the soft thresholding step comprises constant or variant thresholding sizes.
The system of claim 8, wherein the scaled-gradient descent step comprises constant or variant step sizes.
The system of claim 8, wherein the framelet-based iterative algorithm further comprises a color reconstruction step.
The system of claim 8, further comprising a CT platform.
The system of claim 8, wherein the soft thresholding step is configured to promote sparsity in the framelet domain.
The system of claim 8, wherein the during non-negativity step, any negative components are set to 0 to maintain positivity of attenuation coefficients (ϕ, θ).
A single scan polychromatic CT image reconstruction system, comprising:
- a. a computer implementing a computer-readable media comprising a single CT scan;
- and
- b. a processor configured to implement a framelet-based iterative algorithm configured for implementing a framelet-based iterative algorithm for CT image reconstruction from the single CT scan, the iterative algorithm comprising:
- i. a scaled-gradient descent step of constant or variant step sizes;
- ii. a non-negativity step;
- iii. a soft thresholding step;
- and
- iv. a color reconstruction step,
- wherein the processor is configured to reconstruct the CT image following the execution of the iterative steps,
- wherein ϕ=ϕ(r) defines a photoelectric component and θ=θ(r) defines a Compton scatter component of the attenuation coefficient μ(r, E) at each point r, and
- wherein the iterative algorithm comprises iterating on n as follows:
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Dependencies are inferred from the claim text.