Pulmonary Lobe Segmentation With Probabilistic Segmentation of the Fissures and a Groupwise Fissure Prior.
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ABSTRACT:
SUBMITTER: Bragman FJS
PROVIDER: S-EPMC5547024 | biostudies-other | 2017 Aug
REPOSITORIES: biostudies-other
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Project description:We present an open-source framework for pulmonary fissure completeness assessment. Fissure incompleteness has been shown to associate with emphysema treatment outcomes, motivating the development of tools that facilitate completeness estimation. Generally, the task of fissure completeness assessment requires accurate detection of fissures and definition of the boundary surfaces separating the lung lobes. The framework we describe acknowledges a) the modular nature of fissure detection and lung lobe segmentation (lobe boundary detection), and b) that methods to address these challenges are varied and continually developing. It is designed to be readily deployable on existing lung lobe segmentation and fissure detection data sets. The framework consists of multiple components: a flexible quality control module that enables rapid assessment of lung lobe segmentations, an interactive lobe segmentation tool exposed through 3D Slicer for handling challenging cases, a flexible fissure representation using particles-based sampling that can handle fissure feature-strength or binary fissure detection images, and a module that performs fissure completeness estimation using voxel counting and a novel surface area estimation approach. We demonstrate the usage of the proposed framework by deploying on 100 cases exhibiting various levels of fissure completeness. We compare the two completeness level approaches and also compare to visual reads. The code is available to the community via github as part of the Chest Imaging Platform and a 3D Slicer extension module.
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Project description:BACKGROUND:Dispute arises in the tumor category of non-small cell lung cancer invading the fissure to the adjacent lobe. The purpose of this study is to determine the long-term prognosis of non-small cell lung cancer with such an invasion and to propose an appropriate T category. METHODS:In total, 53 cases of non-small cell lung cancer invading the fissure to the adjacent lobe (fissure group) were identified in patients who underwent pulmonary resection from 1997 to 2014. Propensity score matching was applied to balance known confounders for prognosis between each paired group, resulting in 3 matched sets (fissure vs T2a, fissure vs T2b, and fissure vs T3). The overall survival of the fissure group was compared with the survival of patients with T2a, T2b, and T3 diseases, as classified in the eighth edition of TNM classification. RESULTS:The 5-year survivals of the T2a, T2b, T3, and fissure groups were 64.2% (95% confidence interval, 53.2-72.6), 54.6% (95% confidence interval, 44.7-65.8), 35.8% (95% confidence interval, 22.8-44.2), and 38.6% (95% confidence interval, 25.0-52.2), respectively. Specifically, the difference between the fissure group and T2a is statistically significant at P = .01; between the fissure group and T2b at P = .02; and between the fissure group and T3 at P = .93. Multivariate analyses indicate that the fissure group had a similar risk of dying as the T3 disease group (hazard ratio, 1.10; 95% confidence interval, 0.69-1.37) and was at a significantly higher risk compared with the T2a group (hazard ratio, 2.34; 95% confidence interval, 1.50-3.39) and T2b group (hazard ratio, 1.71; 95% confidence interval, 1.19-2.76). CONCLUSIONS:On the basis of our single-institution study, we propose that non-small cell lung cancer invading the fissure to the adjacent lobe should be further investigated and the impact on patients' prognoses validated as a T3 disease.
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