HU-based material conversion for BNCT accurate dose estimation

Area of Science:

• Medical Physics
• Radiation Oncology
• Biomedical Engineering

Background:

• Boron Neutron Capture Therapy (BNCT) is an advanced radiation therapy.
• Accurate dose calculation in BNCT is critical for treatment efficacy and patient safety.
• Treatment planning systems (TPS) require precise material characterization for dose estimation.

Purpose of the Study:

• To introduce and evaluate a Hounsfield unit (HU)-based material conversion algorithm in the NeuMANTA BNCT TPS.
• To assess the impact of material composition variations on dose distribution in BNCT.
• To highlight the importance of accurate material assignment for normal tissue and tumor dose calculations.

Main Methods:

• Development of a novel HU-based material conversion algorithm within the NeuMANTA system.
• Refinement of HU value ranges into 96 specific groups corresponding to tissue information.
• Analysis of dose distribution differences based on varying material compositions derived from HU values.

Main Results:

• The HU-based algorithm allows NeuMANTA to convert regions of interest into multiple material compositions.
• Material composition differences can alter normal tissue maximum dose rates by over 10% (biologically equivalent dose) and up to 6% (physically absorbed dose).
• Tumor dose and neutron scattering/moderation are also significantly affected by material composition variations.

Conclusions:

• Accurate material composition is essential for precise dose estimation in BNCT.
• The NeuMANTA system's HU-based algorithm improves the accuracy of material assignment in BNCT treatment planning.
• Precise dose assessment is vital for evaluating normal tissue side effects and predicting tumor control probability in BNCT.