title: Edge map analysis in chest X-rays for automatic pulmonary abnormality screening.
abstract: OBJECTIVE
  Our particular motivator is the need for screening HIV+ populations in resource-constrained regions for the evidence of tuberculosis, using posteroanterior chest radiographs (CXRs).
  
  
  METHODS
  The proposed method is motivated by the observation that abnormal CXRs tend to exhibit corrupted and/or deformed thoracic edge maps. We study histograms of thoracic edges for all possible orientations of gradients in the range [Formula: see text] at different numbers of bins and different pyramid levels, using five different regions-of-interest selection.
  
  
  RESULTS
  We have used two CXR benchmark collections made available by the U.S. National Library of Medicine and have achieved a maximum abnormality detection accuracy (ACC) of 86.36 % and area under the ROC curve (AUC) of 0.93 at 1 s per image, on average.
  
  
  CONCLUSIONS
  We have presented an automatic method for screening pulmonary abnormalities using thoracic edge map in CXR images. The proposed method outperforms previously reported state-of-the-art results.
authors.affiliation: Department of Computer Science, The University of South Dakota, 414 E Clark St., Vermillion, SD, 57069, USA. santosh.kc@usd.edu.|US National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA. santosh.kc@usd.edu.
authors.forename: K C
authors.initials: KC
authors.lastname: Santosh
authors.affiliation: Department of Computer Science, Central Washington University, 400 E University Way, Ellensburg, WA, 98926, USA.
authors.forename: Szilárd
authors.initials: S
authors.lastname: Vajda
authors.affiliation: US National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA.
authors.forename: Sameer
authors.initials: S
authors.lastname: Antani
authors.affiliation: US National Library of Medicine, National Institutes of Health, 8600 Rockville Pike, Bethesda, MD, 20894, USA.
authors.forename: George R
authors.initials: GR
authors.lastname: Thoma
mesh_terms: D000328:Adult; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D012372:ROC Curve; D013902:Radiography, Thoracic / Q000379:methods*; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
keywords: Automation; Chest X-rays; Pulmonary abnormalities; Screening; Thoracic edge map; Tuberculosis