Redundancy-weighted FDK reconstruction for dual-detector combined-scanning CBCT: Practical implementation for image...

Area of Science:

• Medical Imaging
• Radiotherapy Physics
• Image Reconstruction

Background:

• Cone-beam computed tomography (CBCT) is crucial for image-guided particle therapy (IGPT), but conventional systems have limitations.
• Poor soft-tissue contrast, long acquisition times, and motion artifacts hinder adaptive radiotherapy.
• Advanced CBCT reconstruction is needed to improve image quality, reduce scan time, and lower radiation dose.

Purpose of the Study:

• Introduce a Dual Detector Combined Scanning (DDCS) CBCT algorithm to overcome conventional limitations.
• Enhance adaptive radiotherapy through improved real-time patient positioning, dose verification, and motion management.
• Reduce scanning time and imaging artifacts using a dual-source, orthogonal imaging setup and modified Parker-weighting.

Main Methods:

• Developed a dual-detector CBCT system for simultaneous orthogonal projection acquisition.
• Implemented a modified Parker-weighting algorithm to correct distortions and improve reconstruction accuracy.
• Evaluated the system using numerical and physical phantoms, including dynamic motion studies, comparing it to single-detector CBCT.

Main Results:

• DDCS-CBCT achieved higher contrast-to-noise ratio (CNR) and improved spatial resolution.
• Demonstrated significant reduction in motion artifacts and enhanced anatomical visualization.
• Showcased efficiency for faster, reliable patient setup in IGPT with a lower imaging dose.

Conclusions:

• The DDCS-CBCT approach significantly enhances imaging accuracy and reduces scan time for IGRT/IGPT.
• The system offers improved real-time volumetric guidance, supporting online adaptive radiotherapy.
• Findings support the clinical feasibility and integration of DDCS-CBCT into adaptive radiotherapy workflows.