title: Pulmonary fibrosis and emphysema: Is the emphysema type associated with the pattern of fibrosis?
abstract: OBJECTIVE
  To investigate whether the predominant emphysema type is associated with the high resolution computed tomography (HRCT) pattern of fibrosis in combined pulmonary fibrosis and emphysema (CPFE).
  
  
  METHODS
  Fifty-three smokers with upper lobe emphysema and lower lobe pulmonary fibrosis on - HRCT - were retrospectively evaluated. Patients were stratified into 3 groups according to the predominant type of emphysema: Centrilobular (CLE), paraseptal (PSE), CLE = PSE. Patients were also stratified into 3 other groups according to the predominant type of fibrosis on HRCT: Typical usual interstitial pneumonia (UIP), probable UIP and nonspecific interstitial pneumonia (NSIP). HRCTs were scored at 5 predetermined levels for the coarseness of fibrosis (Coarseness), extent of emphysema (emphysema), extent of interstitial lung disease (TotExtILD), extent of reticular pattern not otherwise specified (RetNOS), extent of ground glass opacity with traction bronchiectasis (extGGOBx), extent of pure ground glass opacity and extent of honeycombing. HRCT mean scores, pulmonary function tests, diffusion capacity (DLCO) and systolic pulmonary arterial pressure were compared among the groups.
  
  
  RESULTS
  The predominant type of emphysema was strongly correlated with the predominant type of fibrosis. The centrilobular emphysema group exhibited a significantly higher extent of emphysema (P < 0.001) and a lower extent of interstitial lung disease (P < 0.002), reticular pattern not otherwise specified (P < 0.023), extent of ground glass opacity with traction bronchiectasis (P < 0.002), extent of honeycombing (P < 0.001) and coarseness of fibrosis (P < 0.001) than the paraseptal group. The NSIP group exhibited a significantly higher extent of emphysema (P < 0.05), total lung capacity (P < 0.01) and diffusion capacity (DLCO) (P < 0.05) than the typical UIP group. The typical UIP group exhibited a significantly higher extent of interstitial lung disease, extent of reticular pattern not otherwise specified, extent of ground glass opacity with traction bronchiectasis, extent of honeycombing and coarseness of fibrosis (0.039 > P > 0.000). Although the pulmonary arterial pressure was higher in typical UIP group relative to the NSIP group, the difference was not statistically significant.
  
  
  CONCLUSIONS
  In CPFE patients, paraseptal emphysema is associated more with UIP-HRCT pattern and higher extent of fibrosis than centrilobular emphysema.
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Oikonomou
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Mintzopoulou
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Argyris
authors.initials: A
authors.lastname: Tzouvelekis
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Petros
authors.initials: P
authors.lastname: Zezos
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Zacharis
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Anastasios
authors.initials: A
authors.lastname: Koutsopoulos
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Demosthenes
authors.initials: D
authors.lastname: Bouros
authors.affiliation: Anastasia Oikonomou, Paraskevi Mintzopoulou, Panos Prassopoulos, Department of Radiology, Democritus University of Thrace, Dragana, 68100 Alexandroupolis, Greece.
authors.forename: Panos
authors.initials: P
authors.lastname: Prassopoulos
keywords: Centrilobular; Emphysema; High resolution computed tomography; Nonspecific interstitial pneumonia pattern; Paraseptal; Pulmonary fibrosis; Usual interstitial pneumonia pattern