title: Serial high resolution CT in non-specific interstitial pneumonia: prognostic value of the initial pattern.
abstract: OBJECTIVE
  To assess the relationship between initial CT pattern and serial changes in CT findings and pulmonary function tests (PFTs) in patients with non-specific interstitial pneumonia (NSIP).
  
  
  METHODS
  Serial high resolution (HR) CTs and PFTs were retrospectively analyzed in 38 cases of histologically proven NSIP, including 4 with cellular NSIP, 13 with mixed cellular and fibrotic NSIP, and 21 with fibrotic NSIP. The presence and extent of various CT findings were assessed. A fibrosis index (defined as the ratio of the extent of a reticular/honeycomb pattern to the overall extent of abnormal parenchyma) was derived.
  
  
  RESULTS
  The predominant CT pattern was reticular/honeycomb in 27 (84%) cases and ground-glass/consolidation in 6 (16%) cases. Between scans, mean disease extent reduced by 5.2%. Disease extent reduced by >10% in 13 (34%) and increased by >10% in 6 (16%) patients. Histopathological subtype of NSIP did not correlate with individual CT pattern, predominant pattern, fibrosis index or serial change in disease extent on CT or PFTs. Response on follow-up CT was associated with fibrosis index, predominant pattern and extent of consolidation on initial CT.
  
  
  CONCLUSIONS
  In NSIP disease, progression on CT correlates with the predominant CT pattern, fibrosis index, and extent of consolidation but not with histopathological subtype. An inflammatory (ground-glass/consolidation) predominant pattern is associated with better outcome in terms of disease extent on HRCT.
authors.affiliation: Department of Radiology, Addenbrooke's Hospital, Cambridge, UK. nicholas.screaton@papworth.nhs.uk
authors.forename: N J
authors.initials: NJ
authors.lastname: Screaton
authors.forename: M P
authors.initials: MP
authors.lastname: Hiorns
authors.forename: K S
authors.initials: KS
authors.lastname: Lee
authors.forename: T
authors.initials: T
authors.lastname: Franquet
authors.forename: T
authors.initials: T
authors.lastname: Johkoh
authors.forename: K
authors.initials: K
authors.lastname: Fujimoto
authors.forename: K
authors.initials: K
authors.lastname: Ichikado
authors.forename: T V
authors.initials: TV
authors.lastname: Colby
authors.forename: N L
authors.initials: NL
authors.lastname: Müller
mesh_terms: D018450:Disease Progression; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D049268:Positron-Emission Tomography; D011379:Prognosis; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*