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A comparison of an algorithm for automated sequential beam orientation selection (Cycle) with simulated annealing
Evert Woudstra1, Ben J M Heijmen, Pascal R M Storchi
1Erasmus Medical Center, Daniel den Hoed Cancer Center, Rotterdam, The Netherlands. e.woudstra@erasmusmc.nl
Physics in Medicine and Biology
|March 28, 2008
Summary
The Cycle algorithm and fast-simulated annealing (FSA) achieve similar radiotherapy plan quality. Cycle is faster and uses fewer beam orientations, making it effective for complex treatment planning.
Area of Science:
- Medical Physics
- Radiation Oncology
- Computational Biology
Background:
- Automatic selection of beam orientations is crucial for effective radiotherapy planning.
- The Cycle algorithm was previously developed for optimizing beam selection in treatment planning.
- Fast-simulated annealing (FSA) is a metaheuristic optimization algorithm capable of finding global optima.
Purpose of the Study:
- To compare the performance of the Cycle algorithm against fast-simulated annealing (FSA) for radiotherapy plan generation.
- To evaluate the ability of both algorithms to find optimal solutions in the presence of local optima.
- To assess plan quality, efficiency, and computational speed.
Main Methods:
- Five pancreas and five esophageal cancer cases were selected for comparison.
- Radiotherapy plans were generated using both Cycle and FSA with identical dose and dose-volume constraints.
- The primary outcome measure was the maximum achievable planning target volume (PTV) dose.
Main Results:
- Both Cycle and FSA produced comparable PTV dose values.
- FSA occasionally yielded slightly higher PTV doses but required significantly more beam orientations.
- Cycle demonstrated faster computation times, particularly in large-dimensional search spaces, and effectively minimized unfavorable beam directions.
Conclusions:
- The Cycle algorithm is a viable and efficient alternative to FSA for radiotherapy treatment planning, especially in complex scenarios.
- Cycle's speed and ability to find high-quality plans with fewer beams offer significant advantages.
- Despite potential local optima, Cycle effectively navigates large beam weight spaces to deliver comparable or superior treatment plans.
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