Development of a Monte Carlo–Based Framework for Real-Time Operator Dose Estimation In Interventional X-Ray Procedures
Abstract
Purpose
Occupational radiation exposure to operators during interventional fluoroscopic procedures remains a significant concern. Conventional personal dosimetry provides limited spatial and organ-specific dose information and does not adequately reflect procedure-dependent exposure conditions. Inspired by the European PODIUM project, this study aims to develop a Monte Carlo–based framework for procedure-dependent operator dose estimation using characterization of scattered radiation fields and panel-based dose conversion coefficients.
Methods
Scattered photon fluence was simulated using MCNP under a posterior–anterior (PA) projection geometry representative of interventional fluoroscopy. A spherical detector arrangement sampled angular- and energy-dependent scattered fluence around the irradiation field, and the results were organized into a scatter sphere lookup table. An adult mesh-type reference computational phantom (MRCP) was imported for anatomically realistic operator dose calculations. Six directional field panels corresponding to clinically relevant exposure geometries were defined, and Monte Carlo simulations were performed to quantify panel-specific dose contributions for dose conversion coefficient (DCC) table generation.
Results
The PA scatter sphere simulations produced stable angular-dependent scattered fluence distributions, allowing consistent mapping of fluence contributions to the defined panels. Integration of the MRCP phantom enabled anatomically aligned panel-based dose scoring. Preliminary results demonstrate stable generation of panel-specific DCC tables derived from Monte Carlo–generated scattered radiation fields. Additional simulations incorporating a lead (Pb) curtain showed direction-dependent modifications of the scattered fluence distribution, indicating the framework’s capability to account for shielding effects.
Conclusion
This study establishes a foundational Monte Carlo framework for geometry-aware and procedure-dependent operator dose estimation in interventional fluoroscopy. By combining scatter sphere–based fluence characterization with anatomically realistic phantom modeling, the proposed approach enables systematic generation of panel-specific DCC tables consistent with PODIUM methodology. The framework provides a critical step beyond conventional personal dosimetry toward clinically relevant operator dose assessment and supports future integration with workflow-based dose monitoring systems.