Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements

Ruurd Visser, D.J.L. Wauben, Martijn de Groot, Jeremy Godart, Johannes A. Langendijk, A.A. van't Veld, Erik W. Korevaar

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

PURPOSE: Advanced radiotherapy treatments require appropriate quality assurance (QA) to verify 3D dose distributions. Moreover, increase in patient numbers demand efficient QA-methods. In this study, a time efficient method that combines model-based QA and measurement-based QA was developed; i.e., the hybrid-QA. The purpose of this study was to determine the reliability of the model-based QA and to evaluate time efficiency of the hybrid-QA method.

METHODS: Accuracy of the model-based QA was determined by comparison of COMPASS calculated dose with Monte Carlo calculations for heterogeneous media. In total, 330 intensity modulated radiation therapy (IMRT) treatment plans were evaluated based on the mean gamma index (GI) with criteria of 3%∕3mm and classification of PASS (GI ≤ 0.4), EVAL (0.4 < GI > 0.6), and FAIL (GI ≥ 0.6). Agreement between model-based QA and measurement-based QA was determined for 48 treatment plans, and linac stability was verified for 15 months. Finally, time efficiency improvement of the hybrid-QA was quantified for four representative treatment plans.

RESULTS: COMPASS calculated dose was in agreement with Monte Carlo dose, with a maximum error of 3.2% in heterogeneous media with high density (2.4 g∕cm(3)). Hybrid-QA results for IMRT treatment plans showed an excellent PASS rate of 98% for all cases. Model-based QA was in agreement with measurement-based QA, as shown by a minimal difference in GI of 0.03 ± 0.08. Linac stability was high with an average GI of 0.28 ± 0.04. The hybrid-QA method resulted in a time efficiency improvement of 15 min per treatment plan QA compared to measurement-based QA.

CONCLUSIONS: The hybrid-QA method is adequate for efficient and accurate 3D dose verification. It combines time efficiency of model-based QA with reliability of measurement-based QA and is suitable for implementation within any radiotherapy department.

Original languageEnglish
Article number021710
JournalMedical physics
Volume40
Issue number2
DOIs
Publication statusPublished - Feb 2013

Keywords

  • quality control
  • radiation dosage
  • radiotherapy dosage
  • radiotherapy, intensity-modulated
  • reproducibility of results
  • time factors

Cite this

Visser, R., Wauben, D. J. L., de Groot, M., Godart, J., Langendijk, J. A., van't Veld, A. A., & Korevaar, E. W. (2013). Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements. Medical physics, 40(2), [021710]. https://doi.org/10.1118/1.4774048
Visser, Ruurd ; Wauben, D.J.L. ; de Groot, Martijn ; Godart, Jeremy ; Langendijk, Johannes A. ; van't Veld, A.A. ; Korevaar, Erik W. / Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements. In: Medical physics. 2013 ; Vol. 40, No. 2.
@article{63feec9f60f84f64b6bf1290f68aa1e3,
title = "Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements",
abstract = "PURPOSE: Advanced radiotherapy treatments require appropriate quality assurance (QA) to verify 3D dose distributions. Moreover, increase in patient numbers demand efficient QA-methods. In this study, a time efficient method that combines model-based QA and measurement-based QA was developed; i.e., the hybrid-QA. The purpose of this study was to determine the reliability of the model-based QA and to evaluate time efficiency of the hybrid-QA method.METHODS: Accuracy of the model-based QA was determined by comparison of COMPASS calculated dose with Monte Carlo calculations for heterogeneous media. In total, 330 intensity modulated radiation therapy (IMRT) treatment plans were evaluated based on the mean gamma index (GI) with criteria of 3{\%}∕3mm and classification of PASS (GI ≤ 0.4), EVAL (0.4 < GI > 0.6), and FAIL (GI ≥ 0.6). Agreement between model-based QA and measurement-based QA was determined for 48 treatment plans, and linac stability was verified for 15 months. Finally, time efficiency improvement of the hybrid-QA was quantified for four representative treatment plans.RESULTS: COMPASS calculated dose was in agreement with Monte Carlo dose, with a maximum error of 3.2{\%} in heterogeneous media with high density (2.4 g∕cm(3)). Hybrid-QA results for IMRT treatment plans showed an excellent PASS rate of 98{\%} for all cases. Model-based QA was in agreement with measurement-based QA, as shown by a minimal difference in GI of 0.03 ± 0.08. Linac stability was high with an average GI of 0.28 ± 0.04. The hybrid-QA method resulted in a time efficiency improvement of 15 min per treatment plan QA compared to measurement-based QA.CONCLUSIONS: The hybrid-QA method is adequate for efficient and accurate 3D dose verification. It combines time efficiency of model-based QA with reliability of measurement-based QA and is suitable for implementation within any radiotherapy department.",
keywords = "quality control, radiation dosage, radiotherapy dosage, radiotherapy, intensity-modulated, reproducibility of results, time factors, mensen, monte carlo methode, kwaliteitscontrole, stralingsdosering, radiotherapie dosering, radiotherapie planning, computerondersteund , radiotherapie, intensiteit gemoduleerd, reproduceerbaarheid van de resultaten, tijdsfactoren, tijdschriftartikel",
author = "Ruurd Visser and D.J.L. Wauben and {de Groot}, Martijn and Jeremy Godart and Langendijk, {Johannes A.} and {van't Veld}, A.A. and Korevaar, {Erik W.}",
year = "2013",
month = "2",
doi = "10.1118/1.4774048",
language = "English",
volume = "40",
journal = "Medical physics",
issn = "0094-2405",
publisher = "AAPM - American Association of Physicists in Medicine",
number = "2",

}

Visser, R, Wauben, DJL, de Groot, M, Godart, J, Langendijk, JA, van't Veld, AA & Korevaar, EW 2013, 'Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements' Medical physics, vol. 40, no. 2, 021710. https://doi.org/10.1118/1.4774048

Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements. / Visser, Ruurd; Wauben, D.J.L.; de Groot, Martijn; Godart, Jeremy ; Langendijk, Johannes A.; van't Veld, A.A.; Korevaar, Erik W.

In: Medical physics, Vol. 40, No. 2, 021710, 02.2013.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Efficient and reliable 3D dose quality assurance for IMRT by combining independent dose calculations with measurements

AU - Visser, Ruurd

AU - Wauben, D.J.L.

AU - de Groot, Martijn

AU - Godart, Jeremy

AU - Langendijk, Johannes A.

AU - van't Veld, A.A.

AU - Korevaar, Erik W.

PY - 2013/2

Y1 - 2013/2

N2 - PURPOSE: Advanced radiotherapy treatments require appropriate quality assurance (QA) to verify 3D dose distributions. Moreover, increase in patient numbers demand efficient QA-methods. In this study, a time efficient method that combines model-based QA and measurement-based QA was developed; i.e., the hybrid-QA. The purpose of this study was to determine the reliability of the model-based QA and to evaluate time efficiency of the hybrid-QA method.METHODS: Accuracy of the model-based QA was determined by comparison of COMPASS calculated dose with Monte Carlo calculations for heterogeneous media. In total, 330 intensity modulated radiation therapy (IMRT) treatment plans were evaluated based on the mean gamma index (GI) with criteria of 3%∕3mm and classification of PASS (GI ≤ 0.4), EVAL (0.4 < GI > 0.6), and FAIL (GI ≥ 0.6). Agreement between model-based QA and measurement-based QA was determined for 48 treatment plans, and linac stability was verified for 15 months. Finally, time efficiency improvement of the hybrid-QA was quantified for four representative treatment plans.RESULTS: COMPASS calculated dose was in agreement with Monte Carlo dose, with a maximum error of 3.2% in heterogeneous media with high density (2.4 g∕cm(3)). Hybrid-QA results for IMRT treatment plans showed an excellent PASS rate of 98% for all cases. Model-based QA was in agreement with measurement-based QA, as shown by a minimal difference in GI of 0.03 ± 0.08. Linac stability was high with an average GI of 0.28 ± 0.04. The hybrid-QA method resulted in a time efficiency improvement of 15 min per treatment plan QA compared to measurement-based QA.CONCLUSIONS: The hybrid-QA method is adequate for efficient and accurate 3D dose verification. It combines time efficiency of model-based QA with reliability of measurement-based QA and is suitable for implementation within any radiotherapy department.

AB - PURPOSE: Advanced radiotherapy treatments require appropriate quality assurance (QA) to verify 3D dose distributions. Moreover, increase in patient numbers demand efficient QA-methods. In this study, a time efficient method that combines model-based QA and measurement-based QA was developed; i.e., the hybrid-QA. The purpose of this study was to determine the reliability of the model-based QA and to evaluate time efficiency of the hybrid-QA method.METHODS: Accuracy of the model-based QA was determined by comparison of COMPASS calculated dose with Monte Carlo calculations for heterogeneous media. In total, 330 intensity modulated radiation therapy (IMRT) treatment plans were evaluated based on the mean gamma index (GI) with criteria of 3%∕3mm and classification of PASS (GI ≤ 0.4), EVAL (0.4 < GI > 0.6), and FAIL (GI ≥ 0.6). Agreement between model-based QA and measurement-based QA was determined for 48 treatment plans, and linac stability was verified for 15 months. Finally, time efficiency improvement of the hybrid-QA was quantified for four representative treatment plans.RESULTS: COMPASS calculated dose was in agreement with Monte Carlo dose, with a maximum error of 3.2% in heterogeneous media with high density (2.4 g∕cm(3)). Hybrid-QA results for IMRT treatment plans showed an excellent PASS rate of 98% for all cases. Model-based QA was in agreement with measurement-based QA, as shown by a minimal difference in GI of 0.03 ± 0.08. Linac stability was high with an average GI of 0.28 ± 0.04. The hybrid-QA method resulted in a time efficiency improvement of 15 min per treatment plan QA compared to measurement-based QA.CONCLUSIONS: The hybrid-QA method is adequate for efficient and accurate 3D dose verification. It combines time efficiency of model-based QA with reliability of measurement-based QA and is suitable for implementation within any radiotherapy department.

KW - quality control

KW - radiation dosage

KW - radiotherapy dosage

KW - radiotherapy, intensity-modulated

KW - reproducibility of results

KW - time factors

KW - mensen

KW - monte carlo methode

KW - kwaliteitscontrole

KW - stralingsdosering

KW - radiotherapie dosering

KW - radiotherapie planning, computerondersteund

KW - radiotherapie, intensiteit gemoduleerd

KW - reproduceerbaarheid van de resultaten

KW - tijdsfactoren

KW - tijdschriftartikel

U2 - 10.1118/1.4774048

DO - 10.1118/1.4774048

M3 - Article

VL - 40

JO - Medical physics

JF - Medical physics

SN - 0094-2405

IS - 2

M1 - 021710

ER -