An iterative reconstruction method based on monochromatic images for dual energy CT

Area of Science:

• Medical Imaging
• Computed Tomography
• Image Reconstruction

Background:

• Dual-energy computed tomography (DECT) offers superior material distinguishability over traditional CT.
• DECT reconstruction faces challenges due to nonlinearity and ill-conditioning, hindering image quality and convergence speed.
• Advancements in DECT reconstruction are crucial for its medical and industrial applications.

Purpose of the Study:

• To propose an iterative reconstruction method based on monochromatic images (IRM-MI) for DECT.
• To enhance image quality and achieve faster convergence speed in DECT reconstruction.
• To address the limitations of current DECT reconstruction techniques.

Main Methods:

• Developed an IRM-MI for DECT reconstruction.
• Transformed the DECT problem from basis material image decomposition to monochromatic image decomposition.
• Modified the coefficient matrix to improve convergence by adjusting projection curve angles or reducing the condition number.

Main Results:

• Numerical experiments demonstrated the effectiveness of the IRM-MI method.
• The proposed method showed significantly increased convergence speed compared to the extended algebraic reconstruction technique (E-ART).
• IRM-MI achieved high-quality images with rapid convergence, validated by simulated and real data.

Conclusions:

• An iterative reconstruction method based on monochromatic images (IRM-MI) was successfully developed for DECT material decomposition.
• The method effectively decomposes basis material images, as confirmed by numerical experiments.
• IRM-MI offers a faster convergence rate than the E-ART method for DECT reconstruction.