Changes in airway dimensions on computed tomography scans of children with cystic fibrosis.
BACKGROUND
In cystic fibrosis (CF), chronic bacterial infection and inflammation lead to progressive airway wall thickening and lumen dilatation.


OBJECTIVE
To quantify airway wall thickening and lumen dilatation in children with CF over a 2-year interval.


METHODS
Children with CF (n = 23) who had two computed tomography (CT) scans (CT(cf1) and CT(cf2)) combined with pulmonary function tests (PFTs), with a 2-year interval between measurements, were compared with control subjects (n = 21) who had one CT (CT(controls)). On cross-sectional cut airway-artery pairs, airway wall area (WA), airway lumen area (LA) and perimeter, and arterial area (AA) were quantified. LA/AA (= marker of bronchiectasis), airway wall thickness (AWT), and WA/AA (= markers of wall thickness) were calculated. CT scans were scored using four different scoring systems. PFTs were expressed as percent predicted.


RESULTS
Airway WA-to-AA ratio was 1.45 (p < 0.001) and airway LA-to-AA ratio was 1.92 times higher (p < 0.001) in children with CF compared with age-matched control subjects. LA/AA and WA/AA remained unchanged from CT(cf1) to CT(cf2) and did not increase with age. AWT as a function of airway size increased from CT(cf1) to CT(cf2) by 2% (0.03 mm; p = 0.02). The change in AWT was inversely related to the change in forced expiratory flow between 25 and 75% of expiratory VC (p = 0.002).


CONCLUSIONS
In CF, quantitative measurements of airways on CT scans show an increased ratio between airway LA and AA and progressive airway wall thickening. Scoring systems show progression of bronchiectasis but unchanged AWT. PFTs remained stable.
de Jong
Pim A
PA
Erasmus MC, Sophia Children's Hospital, Department of Pediatric Pulmonology, Dr Molewaterplein 60, 3015 GJ Rotterdam, The Netherlands.
Nakano
Yasutaka
Y
Hop
Wim C
WC
Long
Frederick R
FR
Coxson
Harvey O
HO
Paré
Peter D
PD
Tiddens
Harm A
HA
D000293:Adolescent; D000792:Angiography; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D001239:Inhalation; D008137:Longitudinal Studies; D008297:Male; D013902:Radiography, Thoracic; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D012137:Respiratory System / Q000098:blood supply / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed