SU-E-I-07: Proposal for a Novel Algorithm of Effective Dose Evaluation for Medical Radiation Exposure

Area of Science:

• Medical Physics
• Radiological Protection
• Diagnostic Imaging

Background:

• The validity of effective dose (ED) for medical applications involving partial-organ irradiation is debated.
• Existing methods may not accurately reflect organ doses in procedures like C-arm cone-beam CT.

Purpose of the Study:

• To propose and validate a new algorithm for evaluating effective dose in medical radiation exposure.
• To introduce Relative Volume Factors (RVFs) to account for partially irradiated organs.

Main Methods:

• Applied three ED evaluation methods to five neuro-imaging protocols using a C-arm cone-beam CT.
• Utilized MOSFET-anthropomorphic phantom measurements and Monte Carlo simulations (PCXMC) for validation.
• Compared EDs calculated by the original ICRP algorithm and the proposed new algorithm.

Main Results:

• The new algorithm showed excellent agreement (within 10% difference) with Monte Carlo simulations for all protocols.
• The original ICRP algorithm overestimated effective doses by approximately a factor of two.

Conclusions:

• The proposed algorithm provides a more accurate estimation of effective dose in medical exposures.
• This new method could establish effective dose as a more reliable index for cross-protocol dose comparisons.