Normalized conceptus doses for abdominal radiographic examinations calculated using a Monte Carlo technique

Area of Science:

• Medical Physics
• Radiological Science
• Radiation Dosimetry

Background:

• Accurate estimation of conceptus radiation dose is crucial for abdominal radiographic examinations during pregnancy.
• Existing methods may lack precision across different gestational trimesters.
• Standardized dosimetry is needed for reliable risk assessment.

Purpose of the Study:

• To develop and validate a reliable method for estimating conceptus radiation doses from abdominal radiography for all pregnancy trimesters.
• To provide normalized conceptus doses applicable to various X-ray techniques and units.
• To enable accurate calculation of fetal radiation exposure.

Main Methods:

• Utilized the Monte Carlo N-Particle (MCNP) radiation transport code for dose estimation.
• Validated MCNP computational approach using thermoluminescence dosimetry (TLD) in anthropomorphic phantoms simulating pregnancy.
• Calculated normalized conceptus doses for different kVp and filtration values across three trimesters.

Main Results:

• MCNP simulations showed very good agreement with TLD measurements (max difference 8.1%) and published data (most differences <10%).
• Normalized conceptus doses were determined for first, second, and third trimesters.
• Dose data are applicable to high-frequency or 3-phase 12-pulse generator systems.

Conclusions:

• The developed MCNP-based method provides a reliable approach for estimating conceptus radiation doses.
• Normalized dose data facilitate accurate fetal dose calculation for abdominal radiography.
• The study offers valuable data for radiation protection in pregnant patients.