title: MRI of infiltrative lung disease: comparison with pathologic findings.
abstract: OBJECTIVE
  Our goal was to compare MRI with pathologic findings in patients with chronic infiltrative lung disease.
  
  
  METHODS
  The study included 22 consecutive patients who had MRI and lung biopsy performed within 21 days (median 4 days). Fifteen patients had open lung biopsy: five with idiopathic pulmonary fibrosis, three with extrinsic allergic alveolitis, and seven with miscellaneous conditions. Seven patients had transbronchial biopsy: four with sarcoidosis and three with miscellaneous conditions. All patients had 1.5 T MRI with cardiac-gated T1-, proton density-, and T2-weighted SE sequences.
  
  
  RESULTS
  The predominant patterns of abnormality seen on MR included parenchymal opacification (n = 12), parenchymal opacification and reticulation (n = 2), reticulation (n = 3), nodularity (n = 3), and interlobular septal thickening (n = 1); normal findings were found in 1. The 14 patients with parenchymal opacification included 9 with ground-glass intensity and 5 with consolidation. In 12 of these 14 patients the parenchymal opacification represented an active inflammatory process including alveolitis, pneumonia, and granulomatous inflammation, while in 2 patients it represented fibrosis. Reticulation was shown to represent fibrosis in five of five cases. The three patients with nodules had sarcoidosis.
  
  
  CONCLUSIONS
  The MR findings correlate closely with those seen on lung biopsy. Parenchymal opacification on MR usually indicates the presence of potentially reversible disease, while reticulation usually indicates irreversible fibrosis.
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, Canada.
authors.forename: S L
authors.initials: SL
authors.lastname: Primack
authors.forename: J R
authors.initials: JR
authors.lastname: Mayo
authors.forename: T E
authors.initials: TE
authors.lastname: Hartman
authors.forename: R R
authors.initials: RR
authors.lastname: Miller
authors.forename: N L
authors.initials: NL
authors.lastname: Müller
mesh_terms: D000328:Adult; D000368:Aged; D000542:Alveolitis, Extrinsic Allergic / Q000175:diagnosis / Q000473:pathology; D002675:Child, Preschool; D002908:Chronic Disease; D005260:Female; D006099:Granuloma / Q000175:diagnosis / Q000473:pathology; D006801:Humans; D008168:Lung / Q000098:blood supply / Q000473:pathology; D008171:Lung Diseases / Q000175:diagnosis* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis / Q000473:pathology; D011446:Prospective Studies; D011658:Pulmonary Fibrosis / Q000175:diagnosis / Q000473:pathology; D012507:Sarcoidosis / Q000175:diagnosis / Q000473:pathology