3D Variation in delineation of head and neck organs at risk

Radiation Oncology

Aart A van 't Veld¹  Johannes A Langendijk¹  Harm Meertens¹  Fred R Burlage¹  Olga Chouvalova¹  Henk P Bijl¹  Arash Navran²  Joop C Duppen²  Edwin van den Heuvel³  Roel JHM Steenbakkers¹  Charlotte L Brouwer¹ 

[1] Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands;Department of Radiation Oncology, The Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, the Netherlands;Department of Epidemiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands

关键词: Delineation;    Organs at risk;    Head and neck cancer;    Interobserver agreement;    Interobserver variability;   

Others  :  1160884
DOI  :  10.1186/1748-717X-7-32

 received in 2011-12-23, accepted in 2012-03-13,  发布年份 2012

【 摘 要 】

Background

Consistent delineation of patient anatomy becomes increasingly important with the growing use of highly conformal and adaptive radiotherapy techniques. This study investigates the magnitude and 3D localization of interobserver variability of organs at risk (OARs) in the head and neck area with application of delineation guidelines, to establish measures to reduce current redundant variability in delineation practice.

Methods

Interobserver variability among five experienced radiation oncologists was studied in a set of 12 head and neck patient CT scans for the spinal cord, parotid and submandibular glands, thyroid cartilage, and glottic larynx. For all OARs, three endpoints were calculated: the Intraclass Correlation Coefficient (ICC), the Concordance Index (CI) and a 3D measure of variation (3D SD).

Results

All endpoints showed largest interobserver variability for the glottic larynx (ICC = 0.27, mean CI = 0.37 and 3D SD = 3.9 mm). Better agreement in delineations was observed for the other OARs (range, ICC = 0.32-0.83, mean CI = 0.64-0.71 and 3D SD = 0.9-2.6 mm). Cranial, caudal, and medial regions of the OARs showed largest variations. All endpoints provided support for improvement of delineation practice.

Conclusions

Variation in delineation is traced to several regional causes. Measures to reduce this variation can be: (1) guideline development, (2) joint delineation review sessions and (3) application of multimodality imaging. Improvement of delineation practice is needed to standardize patient treatments.

【 授权许可】

   
2012 Brouwer et al; licensee BioMed Central Ltd.

【 图 表 】

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