Inter-comparison of phantoms for CT numbers to relative electron density (RED)/physical density calibration and influence to dose calculation in TPS

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00064203%3A_____%2F19%3A10395254" target="_blank" >RIV/00064203:_____/19:10395254 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/86652052:_____/19:N0000003

Výsledek na webu

<a href="https://doi.org/10.1088/1742-6596/1248/1/012046" target="_blank" >https://doi.org/10.1088/1742-6596/1248/1/012046</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1742-6596/1248/1/012046" target="_blank" >10.1088/1742-6596/1248/1/012046</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Inter-comparison of phantoms for CT numbers to relative electron density (RED)/physical density calibration and influence to dose calculation in TPS

Popis výsledku v původním jazyce

Six different phantoms (2x CIRS, 1x Agmeco, 1x QUASAR, 1x Gammex, 1x CatPhan) and Varian formulas were used to evaluate their suitability for CT numbers to relative electron density (RED) calibration in the treatment planning system at two centres using two CT scanners. The variability in calibration curve and the influence to dose calculation in the TPS were estimated for 6 MV and 18 MV. The presence of scattering material around inhomogeneities and influence of CT spectra (90 kV, 120 kV, 140 kV) were evaluated. All phantoms were found convenient for calibration except CatPhan where large deviations were observed for dense bone. Phantoms without scatter material around inhomogeneities should be used with caution. Varian formula slightly overestimates calibration curve in the region of 200 - 300 HU. The tolerance level of 10% suggested for RED during commissioning is reasonable as it can cause change in dose of 3% and 1.5% for 6 MV and 18 MV respectively as a very conservative estimate. Calibration curves should be acquired for all scanning protocols with different CT spectra.

Název v anglickém jazyce

Inter-comparison of phantoms for CT numbers to relative electron density (RED)/physical density calibration and influence to dose calculation in TPS

Popis výsledku anglicky

Six different phantoms (2x CIRS, 1x Agmeco, 1x QUASAR, 1x Gammex, 1x CatPhan) and Varian formulas were used to evaluate their suitability for CT numbers to relative electron density (RED) calibration in the treatment planning system at two centres using two CT scanners. The variability in calibration curve and the influence to dose calculation in the TPS were estimated for 6 MV and 18 MV. The presence of scattering material around inhomogeneities and influence of CT spectra (90 kV, 120 kV, 140 kV) were evaluated. All phantoms were found convenient for calibration except CatPhan where large deviations were observed for dense bone. Phantoms without scatter material around inhomogeneities should be used with caution. Varian formula slightly overestimates calibration curve in the region of 200 - 300 HU. The tolerance level of 10% suggested for RED during commissioning is reasonable as it can cause change in dose of 3% and 1.5% for 6 MV and 18 MV respectively as a very conservative estimate. Calibration curves should be acquired for all scanning protocols with different CT spectra.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

30204 - Oncology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Journal of Physics: Conference Series

ISBN

—

ISSN

1742-6588

e-ISSN

—

Počet stran výsledku

6

Strana od-do

—

Název nakladatele

Institute of Physics Publishing

Místo vydání

Bristol

Místo konání akce

Kuala Lumpur

Datum konání akce

11. 11. 2018

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000492968100046