Dataset Information

Survey on fan-beam computed tomography for radiotherapy: Imaging for dose calculation and delineation.

ABSTRACT:

Background and purpose

To obtain an understanding of current practice, professional needs and future directions in the field of fan-beam CT in RT, a survey was conducted. This work presents the collected information regarding the use of CT imaging for dose calculation and structure delineation.

Materials and methods

An online institutional survey was distributed to medical physics experts employed at Belgian and Dutch radiotherapy institutions to assess the status, challenges, and future directions of QA practices for fan-beam CT. A maximum of 143 questions covered topics such as CT scanner availability, CT scanner specifications, QA protocols, treatment simulation workflow, and radiotherapy dose calculation. Answer forms were collected between 1-Sep-2022 and 10-Oct-2022.

Results

A 66 % response rate was achieved, yielding data on a total of 58 CT scanners. For MV photon therapy, all single-energy CT scans are reconstructed in Hounsfield Units for delineation or dose calculation, and a direct- or stoichiometric method was used to convert CT numbers for dose calculation. Limited use of dual-energy CT is reported for photon (N = 3) and proton dose calculations (N = 1). For brachytherapy, most institutions adopt water-based dose calculation, while approximately 26 % of the institutions take tissue heterogeneity into account. Commissioning and regular QA include eleven tasks, which are performed by two or more professions (29/31) with varying frequencies.

Conclusions

Dual usage of a planning CT limits protocol optimization for both tissue characterization and delineation. DECT has been implemented only gradually. A variation of QA testing frequencies and tests are reported.

SUBMITTER: Decabooter E

PROVIDER: S-EPMC10750173 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Publications

Survey on fan-beam computed tomography for radiotherapy: Imaging for dose calculation and delineation.

Decabooter Esther E Hilgers Guido C GC De Rouck Joke J Salvo Koen K Van Wingerden Jacobus J Bosmans Hilde H van der Heyden Brent B Qamhiyeh Sima S Papalazarou Chrysi C Kaatee Robert R Pittomvils Geert G Bogaert Evelien E

Physics and imaging in radiation oncology 20231206

<h4>Background and purpose</h4>To obtain an understanding of current practice, professional needs and future directions in the field of fan-beam CT in RT, a survey was conducted. This work presents the collected information regarding the use of CT imaging for dose calculation and structure delineation.<h4>Materials and methods</h4>An online institutional survey was distributed to medical physics experts employed at Belgian and Dutch radiotherapy institutions to assess the status, challenges, and ...[more]

PMID: 38152701

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Dataset Information

Survey on fan-beam computed tomography for radiotherapy: Imaging for dose calculation and delineation.

Background and purpose

Materials and methods

Results

Conclusions

Publications

Survey on fan-beam computed tomography for radiotherapy: Imaging for dose calculation and delineation.

Similar Datasets

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