Dataset Information

PRIMO Monte Carlo software benchmarked against a reference dosimetry dataset for 6 MV photon beams from Varian linacs.

ABSTRACT:

Background

The software PRIMO for the Monte Carlo simulation of radiotherapy linacs could potentially act as a independent calculation system to verify the calculations of treatment planning systems. We investigated the suitability of the PRIMO default beam parameters to produce accurate dosimetric results for 6 MV photon beams from Varian Clinac 2100 linacs and 6 MV flattening-filter-free photon beams from Varian TrueBeam linacs.

Methods

Simulation results with the DPM algorithm were benchmarked against a published reference dosimetry dataset based on point measurements of 25 dosimetric parameters on a large series of linacs. Studied parameters (for several field sizes and depths) were: PDD, off-axis ratios, and output factors for open fields and IMRT/SBRT-style fields. For the latter, the output factors were also determined with radiochromic film and with a small-sized ionization chamber. Benchmark data, PRIMO simulation results and our experimental results were compared.

Results

PDD, off-axis ratios, and open-field output factors obtained from the simulations with the PRIMO default beam parameters agreed with the benchmark data within 2.4% for Clinac 2100, and within 1.3% for TrueBeam. Higher differences were found for IMRT/SBRT-style output factors: up to 2.8% for Clinac 2100, and up to 3.3% for TrueBeam. Experimental output factors agreed with benchmark data within 1.0% (ionization chamber) and within 1.9% (radiochromic film).

Conclusions

PRIMO default initial beam parameters for 6 MV photon beams from Varian Clinac 2100 linacs and 6 MV FFF photon beams from Varian TrueBeam linacs allowed agreement within 3.3% with a dosimetry database based on measurements of a high number of linacs. This finding represents a first step in the validation of PRIMO for the independent verification of radiotherapy plans.

SUBMITTER: Hermida-Lopez M

PROVIDER: S-EPMC6081807 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

PRIMO Monte Carlo software benchmarked against a reference dosimetry dataset for 6 MV photon beams from Varian linacs.

Hermida-López Marcelino M Sánchez-Artuñedo David D Calvo-Ortega Juan Francisco JF

Radiation oncology (London, England) 20180807 1

<h4>Background</h4>The software PRIMO for the Monte Carlo simulation of radiotherapy linacs could potentially act as a independent calculation system to verify the calculations of treatment planning systems. We investigated the suitability of the PRIMO default beam parameters to produce accurate dosimetric results for 6 MV photon beams from Varian Clinac 2100 linacs and 6 MV flattening-filter-free photon beams from Varian TrueBeam linacs.<h4>Methods</h4>Simulation results with the DPM algorithm ...[more]

PMID: 30086767

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Dataset Information

PRIMO Monte Carlo software benchmarked against a reference dosimetry dataset for 6 MV photon beams from Varian linacs.

Background

Methods

Results

Conclusions

Publications

PRIMO Monte Carlo software benchmarked against a reference dosimetry dataset for 6 MV photon beams from Varian linacs.

Similar Datasets

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