Objective: The purpose of this study was to compare the high-resolution CT findings in patients with pathologically proven bronchiolitis obliterans after lung transplantation with high-resolution CT findings in control subjects.
Materials and methods: High-resolution CT examinations of 15 patients with pathologically proven bronchiolitis obliterans after lung transplantation and 18 control subjects were retrospectively evaluated by two independent observers who were unaware of the diagnosis in each case. All 33 subjects underwent inspiratory high-resolution CT. Five patients with bronchiolitis obliterans and 16 control subjects underwent expiratory CT.
Results: Findings in patients with bronchiolitis obliterans included bronchial dilatation in 80%, mosaic perfusion in 40%, bronchial wall thickening in 27%, and air trapping in 80%, compared with the control subjects with bronchial dilatation in 22%, mosaic perfusion in 22%, and air trapping in 6%. The combination of bronchial dilatation on the inspiratory CT scan and air trapping on the expiratory CT scan was seen only in patients with bronchiolitis obliterans. We calculated good agreement between the two observers (kappa > or = .63).
Conclusion: Air trapping and bronchial dilatation were the two most sensitive and specific findings on high-resolution CT scans of patients with bronchiolitis obliterans. The combination of these two findings was seen exclusively in patients with bronchiolitis obliterans.