title: The Senile Lung as a Possible Source of Pitfalls on Chest Ultrasonography and Computed Tomography.
abstract: BACKGROUND
  Age-associated changes in the pulmonary system could be detected with imaging techniques. Widespread use of lung ultrasonography (US) requires characterization of a normal pattern.
  
  
  OBJECTIVE
  To compare US and computed tomography (CT) findings in healthy subjects undergoing both techniques (with CT as the gold standard).
  
  
  METHODS
  We prospectively selected 59 subjects undergoing chest CT and US on the same day, without a history of smoking, respiratory symptoms, or known pulmonary pathologies. There were 44 patients in group 1 (age ≥60 years - elderly) and 15 patients in group 2 (age ≤50 years - young). Lung US was performed with a convex and a linear probe, and 10 chest areas per patient were analyzed. Convex and linear probe agreement was evaluated by means of the Cohen κ statistic; Fisher's exact test was used to compare categorical variables between groups.
  
  
  RESULTS
  Isolated B-lines were frequent in both group 1 (54.5%) and group 2 (40.0%); the number of chest areas positive for B-lines increased with age (16.1% in group 1 vs. 5.3% in group 2, p = 0.0028). In group 2, we found that 37.5% of subjects with B-lines had at least 1 chest area with multiple B-lines, but only 2 subjects had 2 or more. Moreover, in group 1 the chest CT documented a reticular pattern (2.3%), areas of increased density (9.1%), ground glass (6.8%), cysts (2.3%), bronchiectasis (22.7%), and bronchial thickening (6.8%); in group 2, only cysts (6.7%) and bronchiectasis (6.7%) were found.
  
  
  CONCLUSIONS
  The senile lung is characterized by mild changes on CT and US. Chest areas positive for B-lines increase with age, and focal multiple B-lines can be found. However, diffuse patterns, especially in symptomatic subjects, suggest a different diagnosis.
authors.affiliation: Radiology Unit, Cardiothoracic-Vascular Department, S. Orsola-Malpighi University Hospital, Bologna, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Ciccarese
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Chiesa
authors.forename: Francesco
authors.initials: F
authors.lastname: Feletti
authors.forename: Luca
authors.initials: L
authors.lastname: Vizioli
authors.forename: Milena
authors.initials: M
authors.lastname: Pasquali
authors.forename: Paola
authors.initials: P
authors.lastname: Forti
authors.forename: Marco
authors.initials: M
authors.lastname: Zoli
authors.forename: Maurizio
authors.initials: M
authors.lastname: Zompatori
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D001987:Bronchiectasis / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D003560:Cysts / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography