A NOVEL METHOD FOR ESTIMATING PATIENT-SPECIFIC PRIMARY DOSE IN CONE-BEAM COMPUTED TOMOGRAPHY

Area of Science:

• Medical Physics
• Radiological Imaging
• Computational Dosimetry

Background:

• Cone-beam computed tomography (CBCT) is crucial for medical imaging, but accurate dose estimation is challenging.
• Real-time optimization of scan protocols and patient-specific dose management are essential for minimizing radiation exposure.
• Current dose reconstruction methods can be computationally intensive or lack real-time applicability.

Purpose of the Study:

• To introduce a novel numerical algorithm for estimating primary dose distributions in CBCT reconstructed images.
• To enable real-time scan-protocol optimization and patient-specific dose management.
• To provide a computationally efficient alternative to existing dose estimation techniques.

Main Methods:

• Development of a numerical algorithm based on the ray-tracing technique.
• Utilization of reconstructed voxel data and scanning protocol parameters.
• Validation against Monte Carlo (MC) simulations and conventional model-based dose reconstruction methods.
• Testing on cylindrical water and anthropomorphic head phantoms.

Main Results:

• The proposed algorithm accurately estimates zeroth-order x-ray interactions, showing good agreement with MC and model-based methods.
• The algorithm demonstrates significantly lower computational cost compared to the MC method.
• The method provides a viable approach for primary dose distribution estimation in CBCT.

Conclusions:

• The developed numerical algorithm offers an efficient and accurate method for dose estimation in CBCT.
• This technique supports real-time scan-protocol optimization and patient-specific dose management.
• Further discussion on algorithm improvements and comparisons with model-based methods is provided.