Structural airway abnormalities in infants and young children with cystic fibrosis

Objectives To determine whether the airway structure of infants and young children with cystic fibrosis (CF) differs from that of normal children by using high-resolution computed tomography (HRCT) imaging. Study design Full-inflation, controlled ventilation HRCT images of the lungs were obtained at four anatomic levels in 34 infants with CF (age, 2.4 +/- 1.4 years) and 20 control infants (age, 1.8 +/- 1.4 years). Short axis diameters of all clearly identifiable, round airway/vessel pairs were measured to obtain airway wall thickness (AINT), airway lumen diameter (ALD), and vessel diameter (VD). Results In infants with CF, mean AWT (+/-SD) was 0.58 +/- 0.13 mm, ALD was 1.31 +/- 0.56 mm, and VD was 1.62 +/- 0.58 mm. In control infants, mean AWT was 0.49 +/- 0.13 mm, ALD was 1.07 +/- 0.42 mm, and VD was 1.86 +/- 0.64 mm. Mean AWT and ALD were greater in children with CF than in normal subjects (P < .001). ALD:VD ratios increased with age in patients with CIF compared with control subjects (P = .026). Conclusions The airways of infants and young children with CF have thicker walls and are more dilated than those of normal infants.