Validation of secondary dose calculation system with manufacturer-provided reference beam data using heterogeneous...

Area of Science:

• Medical Physics
• Radiation Oncology
• Dosimetry

Background:

• Accurate dose calculation is crucial for effective radiation therapy.
• Second-check dosimetry systems provide an independent verification of treatment plans.
• The Mobius3D (M3D) system is a widely used tool for this purpose.

Purpose of the Study:

• To evaluate the dose calculation accuracy of the Mobius3D (M3D) system.
• To compare M3D calculations with treatment planning system (TPS) data and phantom measurements.
• To assess M3D's performance across different accelerator types and heterogeneous tissues.

Main Methods:

• Dose calculation accuracy was investigated using heterogeneous phantoms and reference beam data.
• Comparisons were made between M3D, TPS, and measurements in solid water and heterogeneous phantoms.
• Validation included simple and patient treatment plans for Varian and Elekta accelerators.

Main Results:

• M3D demonstrated good agreement with measurements in solid water phantoms for simple plans.
• Slight differences in dose measurements were observed, indicating accelerator type dependency.
• M3D dose measurements showed 5-10% discrepancies in lung and bone regions.

Conclusions:

• The Mobius3D (M3D) system is reasonably accurate as a second-check dosimetry system for patient plans.
• Accelerator type influences M3D's dose calculation accuracy.
• Further investigation into M3D performance in heterogeneous tissues is warranted.