title: Tracheal CT morphology: correlation with distribution and extent of thoracic adipose tissue.
abstract: OBJECTIVE
  To evaluate the relationship between adipose tissue measurements and anterior bowing of the posterior tracheal wall in a large nonselected group of patients undergoing CT pulmonary angiography (CTPA).
  
  
  METHODS
  Consecutive patients undergoing CTPA over a 4-month period were analyzed retrospectively. Using an adapted scoring system (posterior bowing, flattening, mild/moderate or severe anterior bowing of the posterior tracheal membrane), the axial morphology and cross-sectional area of the trachea at the narrowest point and 1 cm above the aortic arch were evaluated. Measurements of adipose tissue were taken (anterior mediastinal fat width, sagittal upper abdominal diameter and subcutaneous fat thickness at the level of the costophrenic angle). Relationships between tracheal morphology and measurements of adipose tissue were analyzed.
  
  
  RESULTS
  296 patients were included (120 males, 176 females, mean age 59 years, range 19-90). Severe anterior bowing of the posterior tracheal wall correlated with increasing sagittal upper abdominal diameter (p = 0.002). Mild/moderate and severe anterior bowing of the posterior tracheal wall correlated with increasing mediastinal fat width (p = 0.000 and p = 0.031, respectively). Tracheal cross-sectional area was inversely correlated with increasing subcutaneous fat thickness (p = 0.022).
  
  
  CONCLUSIONS
  The findings demonstrate a statistically significant relationship between CT tracheal morphology and adipose tissue measurements in a large nonselected population.
  
  
  CONCLUSIONS
  • There is increasing interest in the effects of obesity on the airways. • A relationship between anterior bowing of the posterior tracheal wall and adipose tissue measurements is demonstrated. • This is of clinical relevance in an increasingly obese population. • Further studies with functional correlation are required.
authors.affiliation: Department of Radiology, Charing Cross Hospital, Imperial College HealthcareNHS Trust, 2nd Floor, Fulham Palace Road, Hammersmith, London, W68RF, UK. derfelapdafydd@hotmail.com.
authors.forename: Derfel
authors.initials: D
authors.lastname: Ap Dafydd
authors.affiliation: King's College London, King's Health Partners, King's College Hospital NHS Foundation Trust, London, UK.
authors.forename: Sujal R
authors.initials: SR
authors.lastname: Desai
authors.affiliation: Imperial College, London, UK.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Gordon
authors.affiliation: Imperial College, London, UK.
authors.forename: Susan J
authors.initials: SJ
authors.lastname: Copley
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000473:pathology*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D008482:Mediastinum / Q000473:pathology; D008875:Middle Aged; D009765:Obesity / Q000000981:diagnostic imaging / Q000473:pathology*; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012737:Sex Factors; D050151:Subcutaneous Fat / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods; D014132:Trachea / Q000000981:diagnostic imaging* / Q000473:pathology*; D055815:Young Adult
keywords: CT pulmonary angiography (CTPA); Multi-detector computed tomography; Obesity; Trachea; Tracheobronchomalacia