Dataset Information

Comparison of detector performance in small 6 MV and 6 MV FFF beams using a Versa HD accelerator.

ABSTRACT:

1. background & purpose

Investigate the applicability of a series of detectors in small field dosimetry and the possible differences between their responses to FF and FFF beams. This work extends upon the series of detectors used by other authors to also include metal-oxide-semiconductor field-effect transistors (MOSFETs) detectors and radiochromic film. We also included a later correction of output factors (OFs) recommended by the recently published IAEA´s code of practice TRS 483 on dosimetry of small static fields used in external beam radiotherapy.

2. materials & methods

The OFs, profiles, and PDDs of 6 MV and 6 MV FFF beams were measured with 11 different detectors using field sizes between 0.6 × 0.6 cm2 and 10 × 10 cm2.

3. results

The OFs of the FFF beams were lower than those of the FF beams for field sizes larger than 3 × 3 cm2 but higher for field sizes smaller than 3 × 3 cm2. After applying the IAEA´s TRS 483 corrections, the final OFs were compatible with our initial results when considering uncertainties involved. Small-volume detectors are preferable for measuring the penumbra of these small fields where this attribute is higher in the crossline direction than in the inline direction. The R100 of equivalent-quality FFF beams was higher compared to the corresponding flattened beams.

4. conclusions

We observed no difference for the dose responses between 6 MV and 6 MV FFF beams for any of the detectors. OF results, profiles and PDDs were clearly consistent with the previously published literature regarding the Versa HD linac. Correcting our first OFs, taken as ratio of detector charges, with the IAEA´s TRS 483 corrections to obtain the final OFs, did not make the former significantly different.

SUBMITTER: Monasor Denia P

PROVIDER: S-EPMC6411166 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Comparison of detector performance in small 6 MV and 6 MV FFF beams using a Versa HD accelerator.

Monasor Denia Paula P Castellet García María Del Carmen MDC Manjón García Carla C Quirós Higueras Juan David JD de Marco Blancas Noelia N Bonaque Alandí Jorge J Juan Senabre Xavier Jordi XJ Santos Serra Agustín A López-Tarjuelo Juan J

PloS one 20190311 3

<h4>1. background & purpose</h4>Investigate the applicability of a series of detectors in small field dosimetry and the possible differences between their responses to FF and FFF beams. This work extends upon the series of detectors used by other authors to also include metal-oxide-semiconductor field-effect transistors (MOSFETs) detectors and radiochromic film. We also included a later correction of output factors (OFs) recommended by the recently published IAEA´s code of practice TRS 483 on do ...[more]

PMID: 30856183

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Dataset Information

Comparison of detector performance in small 6 MV and 6 MV FFF beams using a Versa HD accelerator.

1. background & purpose

2. materials & methods

3. results

4. conclusions

Publications

Comparison of detector performance in small 6 MV and 6 MV FFF beams using a Versa HD accelerator.

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