Intercomparison of Phantoms for CT Numbers to Relative Electron Density (RED)/Physical Density Calibration and Influence to Dose Calculation in TPS

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F86652052%3A_____%2F18%3AN0000001" target="_blank" >RIV/86652052:_____/18:N0000001 - isvavai.cz</a>

Result on the web

<a href="https://docs.wixstatic.com/ugd/3110be_f271f132c62f4b788f07426476a369b3.pdf" target="_blank" >https://docs.wixstatic.com/ugd/3110be_f271f132c62f4b788f07426476a369b3.pdf</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Intercomparison of Phantoms for CT Numbers to Relative Electron Density (RED)/Physical Density Calibration and Influence to Dose Calculation in TPS

Original language description

Calibration curves from CT numbers to electron/physical densities in treatment planning systems (TPS) is an important part of commissioning. The aim of this work was to compare phantoms manufactured by different vendors. 6 phantoms were included in the study (2x CIRS, 1x Agmeco, 1x QUASAR, 1x Gammex, 1x CatPhan) to evaluate the sensitivity of dose calculated by TPS to calibration curve. All phantoms were scanned at two centres with 2 CT scanners under different protocols with various kV. The influence of different calibration curves on dose calculation in the TPS has been estimated. The presence of titanium and the scattering material has been evaluated. The sensitivity of RED to dose is higher for CT numbers higher than 100 HU (10% change in RED caused 3% and 1,5% in dose for 6MV and 18 MV respectively for material of 10 cm thickness). The largest sensitivity was observed for dense bone (up to 3,5% in dose for 6MV). The CT spectra can influence doses up to 4,5% and 2,5% for 6MV and 18 MV respectively. Two phantoms by the same vendor differed for dense bone up to 2% and 1% in dose for 6MV and 18 MV respectively. Phantoms used for CT-RED calibration were compared and various conditions and their influence to dose calculated by TPS was evaluated. Presented at 18th Asia-Oceania Congress of Medical Physics & 16th South-East Asia Congress of Medical Physics, A sustainable Future for Medical Physics: Book of Abstracts, 11th-14th November 2018, Kuala Lumpur, Malaysia (p. 141, A124).

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20601 - Medical engineering

Project

<a href="/en/project/FV20411" target="_blank" >FV20411: Radiotherapy Treatment Planning System - the most advanced optimization algorithms for 3D dose calculation of external beams in the body and their integration into the new generation of the treatment planning system.</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

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