title: Idiopathic interstitial pneumonias: diagnostic accuracy of thin-section CT in 129 patients.
abstract: OBJECTIVE
  To determine whether idiopathic interstitial pneumonias can be differentiated on the basis of the pattern and distribution of abnormalities at thin-section computed tomography (CT).
  
  
  METHODS
  Thin-section CT scans in 129 patients with histologically proved idiopathic interstitial pneumonia (35 with usual interstitial pneumonia [UIP], 24 with bronchiolitis obliterans organizing pneumonia [BOOP], 23 with desquamative interstitial pneumonia [DIP], 20 with acute interstitial pneumonia [AIP], and 27 with nonspecific interstitial pneumonia and fibrosis [NIPF]) were independently assessed by two observers without knowledge of clinical or histologic data. The observers recorded the abnormalities, diagnosis, and degree of confidence in their diagnosis. Differential diagnosis was limited to the five types of idiopathic interstitial pneumonia.
  
  
  RESULTS
  The two observers made a correct diagnosis, on average, in 74 (57%) cases. On average, the correct diagnosis was made in 25 (71%) cases of UIP, 19 (79%) of BOOP, 14.5 (63%) of DIP, 13 (65%) of AIP, and 2.5 (9%) of NIPF. The two observers made a correct diagnosis with a high degree of confidence in 50 (39%) readings. There was moderate agreement between the observers for the correct diagnosis (k = 0.55) and for the correct diagnosis with a high degree of confidence (k = 0.65).
  
  
  CONCLUSIONS
  Except for NIPF, the various subtypes of idiopathic interstitial pneumonias often have a characteristic appearance that allows differentiation at thin-section CT.
authors.affiliation: Dept of Radiology, Vancouver Hospital and Health Sciences Centre, BC, Canada.
authors.forename: T
authors.initials: T
authors.lastname: Johkoh
authors.forename: N L
authors.initials: NL
authors.lastname: Müller
authors.forename: Y
authors.initials: Y
authors.lastname: Cartier
authors.forename: P V
authors.initials: PV
authors.lastname: Kavanagh
authors.forename: T E
authors.initials: TE
authors.lastname: Hartman
authors.forename: M
authors.initials: M
authors.lastname: Akira
authors.forename: K
authors.initials: K
authors.lastname: Ichikado
authors.forename: M
authors.initials: M
authors.lastname: Ando
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods