Dataset Information

Cranial organs at risk delineation: heterogenous practices in radiotherapy planning.

ABSTRACT:

Background

Segmentation is a crucial step in treatment planning that directly impacts dose distribution and optimization. The aim of this study was to evaluate the inter-individual variability of common cranial organs at risk (OAR) delineation in neurooncology practice.

Methods

Anonymized simulation contrast-enhanced CT and MR scans of one patient with a solitary brain metastasis was used for delineation and analysis. Expert professionals from 16 radiotherapy centers involved in brain structures delineation were asked to segment 9 OAR on their own treatment planning system. As reference, two experts in neurooncology, produced a unique consensual contour set according to guidelines. Overlap ratio, Kappa index (KI), volumetric ratio, Commonly Contoured Volume, Supplementary Contoured Volume were evaluated using Artiview™ v 2.8.2-according to occupation, seniority and level of expertise of all participants.

Results

For the most frequently delineated and largest OAR, the mean KI are often good (0.8 for the parotid and the brainstem); however, for the smaller OAR, KI degrade (0.3 for the optic chiasm, 0.5% for the cochlea), with a significant discrimination (p?ConclusionOur study illustrates the heterogeneity in normal structures contouring between professionals. We emphasize the need for cerebral OAR delineation harmonization-that is a major determinant of therapeutic ratio and clinical trials evaluation.

SUBMITTER: Vogin G

PROVIDER: S-EPMC7863275 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Cranial organs at risk delineation: heterogenous practices in radiotherapy planning.

Vogin Guillaume G Hettal Liza L Bartau Clarisse C Thariat Juliette J Claeys Marie-Virginie MV Peyraga Guillaume G Retif Paul P Schick Ulrike U Antoni Delphine D Bodgal Zsuzsa Z Dhermain Frederic F Feuvret Loic L

Radiation oncology (London, England) 20210204 1

<h4>Background</h4>Segmentation is a crucial step in treatment planning that directly impacts dose distribution and optimization. The aim of this study was to evaluate the inter-individual variability of common cranial organs at risk (OAR) delineation in neurooncology practice.<h4>Methods</h4>Anonymized simulation contrast-enhanced CT and MR scans of one patient with a solitary brain metastasis was used for delineation and analysis. Expert professionals from 16 radiotherapy centers involved in b ...[more]

PMID: 33541394

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Dataset Information

Cranial organs at risk delineation: heterogenous practices in radiotherapy planning.

Background

Methods

Results

Publications

Cranial organs at risk delineation: heterogenous practices in radiotherapy planning.

Similar Datasets

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