title: Thin-section CT obtained at 10-mm increments versus limited three-level thin-section CT for idiopathic pulmonary fibrosis: correlation with pathologic scoring.
abstract: OBJECTIVE
  The purpose of our study was to determine if three-level thin-section CT depicts idiopathic pulmonary fibrosis (IPF) pathology as accurately as CT obtained at 10-mm increments throughout the entire lungs.
  
  
  METHODS
  Thin-section (1.0- to 1.5-mm) images at 10-mm increments were obtained and scored prospectively in 25 consecutive patients with newly diagnosed IPF who were participating in a Special Center of Research grant for interstitial lung disease. Each patient's lobe was scored by four thoracic radiologists on a scale of 0-5 for both ground-glass attenuation and fibrosis. The radiologists used three images (limited CT) and also used the entire data set (complete CT). CT scores were compared with pathology scores from 67 open and thoracoscopic biopsies. Limited and complete scores were compared with each other (Pearson correlation coefficient). Interobserver variation in the CT scoring system was assessed using kappa values.
  
  
  RESULTS
  CT fibrosis scores strongly correlated with pathology fibrosis scores for complete (r = .53, p = .0001) and limited (r = .50, p = .0001) CT. CT ground-glass scores correlated with the histologic inflammatory scores for each lobe on complete (r = .27, p = .03) and limited (r = .26, p = .03) CT. The desquamative subcomponent of the pathology inflammatory score had the highest correlation with the CT ground-glass scores (complete: r = .29, p = .01; limited: r = .33, p = .007). Good interobserver agreement existed for both the alveolar and fibrosis components of the CT scoring system (kappa values ranging from .51 to .83) for each lobe of the lung on limited and complete CT.
  
  
  CONCLUSIONS
  Limited thin-section CT reveals the pathologic changes associated with IPF as well as CT obtained at 10-mm increments. An added advantage of limited thin-section CT is that it exposes patients to less radiation.
authors.affiliation: Department of Radiology, University of Michigan Hospitals, Ann Arbor 48109-0326, USA.
authors.forename: E A
authors.initials: EA
authors.lastname: Kazerooni
authors.forename: F J
authors.initials: FJ
authors.lastname: Martinez
authors.forename: A
authors.initials: A
authors.lastname: Flint
authors.forename: D A
authors.initials: DA
authors.lastname: Jamadar
authors.forename: B H
authors.initials: BH
authors.lastname: Gross
authors.forename: D L
authors.initials: DL
authors.lastname: Spizarny
authors.forename: P N
authors.initials: PN
authors.lastname: Cascade
authors.forename: R I
authors.initials: RI
authors.lastname: Whyte
authors.forename: J P
authors.initials: JP
authors.lastname: Lynch
authors.forename: G
authors.initials: G
authors.lastname: Toews
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D011658:Pulmonary Fibrosis / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*