title: Hybrid method for the detection of pulmonary nodules using positron emission tomography/computed tomography: a preliminary study.
abstract: OBJECTIVE
  In this study, an automated scheme for detecting pulmonary nodules using a novel hybrid PET/CT approach is proposed, which is designed to detect pulmonary nodules by combining data from both sets of images.
  
  
  METHODS
  Solitary nodules were detected on CT by a cylindrical filter that we developed previously, and in the PET imaging, high-uptake regions were detected automatically using thresholding based on standardized uptake values along with false-positive reduction by means of the anatomical information obtained from the CT images. Initial candidate nodules were identified by combining the results. False positives among the initial candidates were eliminated by a rule-based classifier and three support vector machines on the basis of the characteristic features obtained from CT and PET images.
  
  
  RESULTS
  We validated the proposed method using 100 cases of PET/CT images that were obtained during a cancer-screening program. The detection performance was assessed by free-response receiver operating characteristic (FROC) analysis. The sensitivity was 83.0% with the number of false positives/case at 5.0, and it was 8% higher than the sensitivity of independent detection systems using CT or PET images alone.
  
  
  CONCLUSIONS
  Detection performance indicates that our method may be of practical use for the identification of pulmonary nodules in PET/CT images.
authors.affiliation: Faculty of Radiological Technology, School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake, Toyoake, Aichi, 470-1192, Japan, teramoto@fujita-hu.ac.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Teramoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujita
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Takahashi
authors.forename: Osamu
authors.initials: O
authors.lastname: Yamamuro
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Tamaki
authors.forename: Masami
authors.initials: M
authors.lastname: Nishio
authors.forename: Toshiki
authors.initials: T
authors.lastname: Kobayashi
mesh_terms: D003937:Diagnosis, Differential; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis*; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D012372:ROC Curve; D015203:Reproducibility of Results; D003074:Solitary Pulmonary Nodule / Q000175:diagnosis*; D014057:Tomography, X-Ray Computed / Q000379:methods*