title: Role of the texture features of images in the diagnosis of solitary pulmonary nodules in different sizes.
abstract: OBJECTIVE
  To explore the role of the texture features of images in the diagnosis of solitary pulmonary nodules (SPNs) in different sizes.
  
  
  METHODS
  A total of 379 patients with pathologically confirmed SPNs were enrolled in this study. They were divided into three groups based on the SPN sizes: ≤10, 11-20, and >20 mm. Their texture features were segmented and extracted. The differences in the image features between benign and malignant SPNs were compared. The SPNs in these three groups were determined and analyzed with the texture features of images.
  
  
  RESULTS
  These 379 SPNs were successfully segmented using the 2D Otsu threshold method and the self-adaptive threshold segmentation method. The texture features of these SPNs were obtained using the method of grey level co-occurrence matrix (GLCM). Of these 379 patients, 120 had benign SPNs and 259 had malignant SPNs. The entropy, contrast, energy, homogeneity, and correlation were 3.5597±0.6470, 0.5384±0.2561, 0.1921±0.1256, 0.8281±0.0604, and 0.8748±0.0740 in the benign SPNs and 3.8007±0.6235, 0.6088±0.2961, 0.1673±0.1070, 0.7980±0.0555, and 0.8550±0.0869 in the malignant SPNs (all P<0.05). The sensitivity, specificity, and accuracy of the texture features of images were 83.3%, 90.0%, and 86.8%, respectively, for SPNs sized ≤10 mm, and were 86.6%, 88.2%, and 87.1%, respectively, for SPNs sized  11-20 mm and 94.7%, 91.8%, and 93.9%, respectively, for SPNs sized >20 mm.
  
  
  CONCLUSIONS
  The entropy and contrast of malignant pulmonary nodules have been demonstrated to be higher in comparison to those of benign pulmonary nodules, while the energy, homogeneity correlation of malignant pulmonary nodules are lower than those of benign pulmonary nodules. The texture features of images can reflect the tissue features and have high sensitivity, specificity, and accuracy in differentiating SPNs. The sensitivity and accuracy increase for larger SPNs.
authors.affiliation: 1 Department of Statistics, School of Public Health, Guangzhou Medical University, Guangzhou 510182, China ; 2 Medical Imaging Center, the First Affiliated hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: 1 Department of Statistics, School of Public Health, Guangzhou Medical University, Guangzhou 510182, China ; 2 Medical Imaging Center, the First Affiliated hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Chang-Zheng
authors.initials: CZ
authors.lastname: Shi
authors.affiliation: 1 Department of Statistics, School of Public Health, Guangzhou Medical University, Guangzhou 510182, China ; 2 Medical Imaging Center, the First Affiliated hospital of Jinan University, Guangzhou 510630, China.
authors.forename: Liang-Ping
authors.initials: LP
authors.lastname: Luo
keywords: Solitary pulmonary nodules (SPNs); differentiation; image features; textures