Cargando…

Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)

PURPOSE: The purpose of this study was to evaluate the quality of automatically propagated contours of organs at risk (OARs) based on respiratory‐correlated navigator‐triggered four‐dimensional magnetic resonance imaging (RC‐4DMRI) for calculation of internal organ‐at‐risk volume (IRV) to account fo...

Descripción completa

Detalles Bibliográficos
Autores principales: Zhang, Jingjing, Markova, Svetlana, Garcia, Alejandro, Huang, Kirk, Nie, Xingyu, Choi, Wookjin, Lu, Wei, Wu, Abraham, Rimner, Andreas, Li, Guang
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6123161/
https://www.ncbi.nlm.nih.gov/pubmed/30112797
http://dx.doi.org/10.1002/acm2.12431
_version_ 1783352802502770688
author Zhang, Jingjing
Markova, Svetlana
Garcia, Alejandro
Huang, Kirk
Nie, Xingyu
Choi, Wookjin
Lu, Wei
Wu, Abraham
Rimner, Andreas
Li, Guang
author_facet Zhang, Jingjing
Markova, Svetlana
Garcia, Alejandro
Huang, Kirk
Nie, Xingyu
Choi, Wookjin
Lu, Wei
Wu, Abraham
Rimner, Andreas
Li, Guang
author_sort Zhang, Jingjing
collection PubMed
description PURPOSE: The purpose of this study was to evaluate the quality of automatically propagated contours of organs at risk (OARs) based on respiratory‐correlated navigator‐triggered four‐dimensional magnetic resonance imaging (RC‐4DMRI) for calculation of internal organ‐at‐risk volume (IRV) to account for intra‐fractional OAR motion. METHODS AND MATERIALS: T2‐weighted RC‐4DMRI images were of 10 volunteers acquired and reconstructed using an internal navigator‐echo surrogate and concurrent external bellows under an IRB‐approved protocol. Four major OARs (lungs, heart, liver, and stomach) were delineated in the 10‐phase 4DMRI. Two manual‐contour sets were delineated by two clinical personnel and two automatic‐contour sets were propagated using free‐form deformable image registration. The OAR volume variation within the 10‐phase cycle was assessed and the IRV was calculated as the union of all OAR contours. The OAR contour similarity between the navigator‐triggered and bellows‐rebinned 4DMRI was compared. A total of 2400 contours were compared to the most probable ground truth with a 95% confidence level (S95) in similarity, sensitivity, and specificity using the simultaneous truth and performance level estimation (STAPLE) algorithm. RESULTS: Visual inspection of automatically propagated contours finds that approximately 5–10% require manual correction. The similarity, sensitivity, and specificity between manual and automatic contours are indistinguishable (P > 0.05). The Jaccard similarity indexes are 0.92 ± 0.02 (lungs), 0.89 ± 0.03 (heart), 0.92 ± 0.02 (liver), and 0.83 ± 0.04 (stomach). Volume variations within the breathing cycle are small for the heart (2.6 ± 1.5%), liver (1.2 ± 0.6%), and stomach (2.6 ± 0.8%), whereas the IRV is much larger than the OAR volume by: 20.3 ± 8.6% (heart), 24.0 ± 8.6% (liver), and 47.6 ± 20.2% (stomach). The Jaccard index is higher in navigator‐triggered than bellows‐rebinned 4DMRI by 4% (P < 0.05), due to the higher image quality of navigator‐based 4DMRI. CONCLUSION: Automatic and manual OAR contours from Navigator‐triggered 4DMRI are not statistically distinguishable. The navigator‐triggered 4DMRI image provides higher contour quality than bellows‐rebinned 4DMRI. The IRVs are 20–50% larger than OAR volumes and should be considered in dose estimation.
format Online
Article
Text
id pubmed-6123161
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher John Wiley and Sons Inc.
record_format MEDLINE/PubMed
spelling pubmed-61231612018-09-10 Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV) Zhang, Jingjing Markova, Svetlana Garcia, Alejandro Huang, Kirk Nie, Xingyu Choi, Wookjin Lu, Wei Wu, Abraham Rimner, Andreas Li, Guang J Appl Clin Med Phys Radiation Oncology Physics PURPOSE: The purpose of this study was to evaluate the quality of automatically propagated contours of organs at risk (OARs) based on respiratory‐correlated navigator‐triggered four‐dimensional magnetic resonance imaging (RC‐4DMRI) for calculation of internal organ‐at‐risk volume (IRV) to account for intra‐fractional OAR motion. METHODS AND MATERIALS: T2‐weighted RC‐4DMRI images were of 10 volunteers acquired and reconstructed using an internal navigator‐echo surrogate and concurrent external bellows under an IRB‐approved protocol. Four major OARs (lungs, heart, liver, and stomach) were delineated in the 10‐phase 4DMRI. Two manual‐contour sets were delineated by two clinical personnel and two automatic‐contour sets were propagated using free‐form deformable image registration. The OAR volume variation within the 10‐phase cycle was assessed and the IRV was calculated as the union of all OAR contours. The OAR contour similarity between the navigator‐triggered and bellows‐rebinned 4DMRI was compared. A total of 2400 contours were compared to the most probable ground truth with a 95% confidence level (S95) in similarity, sensitivity, and specificity using the simultaneous truth and performance level estimation (STAPLE) algorithm. RESULTS: Visual inspection of automatically propagated contours finds that approximately 5–10% require manual correction. The similarity, sensitivity, and specificity between manual and automatic contours are indistinguishable (P > 0.05). The Jaccard similarity indexes are 0.92 ± 0.02 (lungs), 0.89 ± 0.03 (heart), 0.92 ± 0.02 (liver), and 0.83 ± 0.04 (stomach). Volume variations within the breathing cycle are small for the heart (2.6 ± 1.5%), liver (1.2 ± 0.6%), and stomach (2.6 ± 0.8%), whereas the IRV is much larger than the OAR volume by: 20.3 ± 8.6% (heart), 24.0 ± 8.6% (liver), and 47.6 ± 20.2% (stomach). The Jaccard index is higher in navigator‐triggered than bellows‐rebinned 4DMRI by 4% (P < 0.05), due to the higher image quality of navigator‐based 4DMRI. CONCLUSION: Automatic and manual OAR contours from Navigator‐triggered 4DMRI are not statistically distinguishable. The navigator‐triggered 4DMRI image provides higher contour quality than bellows‐rebinned 4DMRI. The IRVs are 20–50% larger than OAR volumes and should be considered in dose estimation. John Wiley and Sons Inc. 2018-08-15 /pmc/articles/PMC6123161/ /pubmed/30112797 http://dx.doi.org/10.1002/acm2.12431 Text en © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine. This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Radiation Oncology Physics
Zhang, Jingjing
Markova, Svetlana
Garcia, Alejandro
Huang, Kirk
Nie, Xingyu
Choi, Wookjin
Lu, Wei
Wu, Abraham
Rimner, Andreas
Li, Guang
Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title_full Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title_fullStr Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title_full_unstemmed Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title_short Evaluation of automatic contour propagation in T2‐weighted 4DMRI for normal‐tissue motion assessment using internal organ‐at‐risk volume (IRV)
title_sort evaluation of automatic contour propagation in t2‐weighted 4dmri for normal‐tissue motion assessment using internal organ‐at‐risk volume (irv)
topic Radiation Oncology Physics
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6123161/
https://www.ncbi.nlm.nih.gov/pubmed/30112797
http://dx.doi.org/10.1002/acm2.12431
work_keys_str_mv AT zhangjingjing evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT markovasvetlana evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT garciaalejandro evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT huangkirk evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT niexingyu evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT choiwookjin evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT luwei evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT wuabraham evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT rimnerandreas evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv
AT liguang evaluationofautomaticcontourpropagationint2weighted4dmrifornormaltissuemotionassessmentusinginternalorganatriskvolumeirv