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Updated: Dec 24, 2025

10:44
Three-Dimensional Phase Resolved Functional Lung Magnetic Resonance Imaging
Published on: June 21, 2024
971
An Exact and Fast CBCT Reconstruction via Pseudo-Polar Fourier Transform based Discrete Grangeat's Formula
Summary
This study introduces a new method for fast 3D image reconstruction in sparse view angle Cone Beam CT (CBCT) using Fourier Based Iterative Reconstruction Method (FIRM). The approach generates 3D Radon space from cone beam projections for accurate and artifact-free 3D imaging.
Area of Science:
- Medical Imaging
- Computational Imaging
- Image Reconstruction
Background:
- Fan beam Computed Tomography (CT) using Fourier Based Iterative Reconstruction Method (FIRM) enables fast, high-quality 2D imaging with limited projections.
- Cone Beam CT (CBCT) requires efficient 3D image reconstruction methods, especially with sparse view angles.
Purpose of the Study:
- To develop a methodology for generating 3D Radon space from cone beam projections (CBP) to enable FIRM application in sparse view angle CBCT.
- To achieve fast and accurate 3D image reconstruction in CBCT, minimizing artifacts.
Main Methods:
- Generation of 3D Radon space using Grangeat's formula, optimized and discretized with CBP data.
- Application of fast Pseudo Polar Fourier Transform (PPFT) based on 2D and 3D Discrete Radon Transformation (DRT) algorithms.
- Direct inverse 3D PPFT for object reconstruction, eliminating interpolation-induced noise and artifacts.
Main Results:
- The proposed method successfully generates 3D Radon space from CBP data.
- Reconstruction using direct inverse 3D PPFT eliminates common artifacts like thorns, V-shapes, and wrinkles.
- The Cone2Radon and MATLAB/Python toolboxes demonstrated fast and accurate 3D image reconstruction on digital phantoms.
Conclusions:
- The presented methodology effectively facilitates FIRM for sparse view angle CBCT 3D image reconstruction.
- The approach offers a significant improvement in speed and accuracy while reducing artifacts in CBCT imaging.
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