Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/32698
Title: Lung tumor delineation in PET-CT images based on a new segmentation energy
Authors: Ballangan, C
Wang, X
Feng, D
Keywords: Computerised tomography
Image segmentation
Lung
Medical image processing
Positron emission tomography
Tumours
Issue Date: 2011
Publisher: IEEE
Source: 2011 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 23-29 October 2011, Valencia, p. 3202-3205 How to cite?
Abstract: Accurate lung tumor delineation from positron emission tomography (PET) - computed tomography (CT) images is important for patient management. However, this task is challenging, especially when a tumor abuts or involves the chest wall or mediastinum; or when it is located in close proximity to the heart or liver. Combining PET and CT can improve the accuracy of tumor delineation, but current methods might be prone to leakage or require that the tumor already be isolated within a box. In this paper, we proposed a tumor delineation method with a novel energy function using information from both CT and PET with a downhill cost. We added a penalty to the energy function such that when a voxel is not part of the downhill region, the energy will be the negative of the initial energy. With this formulation, the contour did not move outside the downhill region thus delineation leakage can be avoided. We incorporated our proposed energy function into a region-based active contour to address the issue of insufficient gradient information when a tumor is connected to surrounding organs of similar intensity. We implemented the segmentation using a localized active contour to focus on the voxels near the tumor, without considering all the global intensities. Out method only required a seed point from which the maximum intensity in PET can be found and used to define a downhill region for the energy function. We evaluated our method in 20 PET-CT studies, from which 10 studies with manual delineation were used for quantitative evaluation and 10 studies where the tumors abutted or involved the chest wall, mediastinum or diaphragm were used for qualitative evaluation. Experiments demonstrated that our method: (1) achieved the highest overlap compared to other approaches that used PET only, CT only, and combined PET-CT without the downhilAccurate lung tumor delineation from positron emission tomography (PET) - computed tomography (CT) images is important for patient management. Howe- er, this task is challenging, especially when a tumor abuts or involves the chest wall or mediastinum; or when it is located in close proximity to the heart or liver. Combining PET and CT can improve the accuracy of tumor delineation, but current methods might be prone to leakage or require that the tumor already be isolated within a box. In this paper, we proposed a tumor delineation method with a novel energy function using information from both CT and PET with a downhill cost. We added a penalty to the energy function such that when a voxel is not part of the downhill region, the energy will be the negative of the initial energy. With this formulation, the contour did not move outside the downhill region thus delineation leakage can be avoided. We incorporated our proposed energy function into a region-based active contour to address the issue of insufficient gradient information when a tumor is connected to surrounding organs of similar intensity. We implemented the segmentation using a localized active contour to focus on the voxels near the tumor, without considering all the global intensities. Out method only required a seed point from which the maximum intensity in PET can be found and used to define a downhill region for the energy function. We evaluated our method in 20 PET-CT studies, from which 10 studies with manual delineation were used for quantitative evaluation and 10 studies where the tumors abutted or involved the chest wall, mediastinum or diaphragm were used for qualitative evaluation. Experiments demonstrated that our method: (1) achieved the highest overlap compared to other approaches that used PET only, CT only, and combined PET-CT without the downhill cost; and (2) avoided leakage in all cases when other approaches suffered leakage.l cost; and (2) avoided leakage in all cases when other approaches suffered leakage.
URI: http://hdl.handle.net/10397/32698
ISBN: 978-1-4673-0118-3
ISSN: 1082-3654
DOI: 10.1109/NSSMIC.2011.6153657
Appears in Collections:Conference Paper

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

3
Citations as of Oct 16, 2017

Page view(s)

48
Last Week
2
Last month
Checked on Oct 15, 2017

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.