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Interpolation of tabulated proton Bragg peaks
Benjamin M Clasie1, Jacob B Flanz, Hanne M Kooy
1Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA, USA. bclasie@partners.org
Physics in Medicine and Biology
|October 18, 2012
Summary
This study introduces an interpolation method for pencil beam scanning treatment planning databases. Using just three tabulated Bragg peaks improves dose calculation accuracy to within ±1% of maximum dose.
Area of Science:
- Medical Physics
- Radiation Oncology
Background:
- Treatment planning databases for pencil beam scanning (PBS) are essential for accurate radiation therapy.
- Large databases with high resolution Bragg peaks pose management and quality assurance challenges.
- Accurate dose calculations require precise representation of Bragg peaks, often necessitating high-resolution data.
Purpose of the Study:
- To develop and validate an approximate scaling function for interpolating between tabulated Bragg peaks.
- To determine the accuracy of this novel interpolation technique.
- To establish the minimum number of tabulated peaks required for accurate dose calculations in PBS.
Main Methods:
- Derivation of an approximate scaling function for Bragg peak interpolation.
- Evaluation of interpolation accuracy against tabulated data.
- Assessment of accuracy for varying numbers of tabulated mono-energetic Bragg peaks (N).
Main Results:
- The proposed scaling function enables accurate interpolation between tabulated Bragg peaks.
- An interpolation accuracy better than ±1% of the maximum dose was achieved.
- A minimum of three tabulated mono-energetic Bragg peaks (N=3) was found to be sufficient for this accuracy.
Conclusions:
- The developed interpolation method significantly enhances the efficiency of treatment planning databases.
- Utilizing N=3 tabulated peaks offers a practical balance between database size and dose calculation accuracy.
- This technique improves quality assurance and management of PBS treatment planning data.
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