Poster - Thur Eve - 77: Coordinate transformation from DICOM to DOSXYZnrc

Area of Science:

• Medical Physics
• Radiotherapy Physics
• Computational Dosimetry

Background:

• DICOM is the standard for radiotherapy data exchange.
• BEAMnrc/DOSXYZnrc requires specific coordinate systems for Monte Carlo simulations.
• Transforming DICOM beam orientation to BEAMnrc/DOSXYZnrc is complex.

Purpose of the Study:

• To derive new, simplified transformation equations for DICOM beam orientation to BEAMnrc/DOSXYZnrc.
• To facilitate easier computational implementation of radiotherapy plan simulations.
• To ensure accurate geometric and dosimetric comparisons between treatment planning systems and Monte Carlo simulations.

Main Methods:

• Derived new transformation equations for polar (θ) and azimuthal (φ) angles.
• Developed a novel method for calculating collimator rotation (Φ_col) by combining actual collimator and couch rotations.
• Applied transformations to clinical plans generated by the Eclipse treatment planning system.

Main Results:

• The new transformation equations are more compact and easier to implement computationally.
• Verification using clinical plans showed exact geometric agreement for field placements.
• Good agreement was observed in dose distributions between treatment planning system and Monte Carlo results.

Conclusions:

• The derived transformation equations provide a more accessible and accurate method for integrating DICOM radiotherapy plans into BEAMnrc/DOSXYZnrc simulations.
• This simplification aids researchers and clinicians in performing precise Monte Carlo dose simulations.
• The findings support the use of these transformations for reliable radiotherapy plan verification.