[Three-dimensional computed tomography in acquired pediatric airway diseases]

To investigate the role of three-dimensional computed tomography (CT) in pediatric tracheobronchial diseases. Eleven male, six female patients aged from two weeks to 12 years (mean age, 3.3 years) were referred to spiral CT with a preliminary diagnosis of foreign body aspiration, extrinsic airway compression, acquired tracheoesophageal fistula, post-intubation stenosis, and bronchial erosion by a cavitary lung lesion. Tracheobronchial tree was scanned with 3 mm collimation, 1.5/1 pitch, 1.5 mm reconstruction interval, and standard reconstruction algorithm. Surface-rendered three-dimensional images and virtual bronchoscopic images were created from the axial raw data. Three-dimensional and virtual bronchoscopy findings were compared with findings of bronchoscopy. Virtual bronchoscopy revealed the level of obstruction in five patients with foreign body aspiration, but failed to disclose the nature of the aspirated foreign body and distinguish between a foreign body and mucoid obstruction. Virtual bronchoscopy correctly ruled out foreign body aspiration in four patients. Axial CT images also showed extraluminal findings including atelectasis, air trapping, peribronchial thickening, and infiltrations. In a patient with tracheitis virtual bronchoscopy failed to identify necrotic plaques observed in bronchoscopy. In patients with extrinsic compression, three-dimensional images showed the site and degrees of stenosis, whereas axial images revealed the cause of compression. In one patient, an anomalous tracheal bronchus was demonstrated on three-dimensional and virtual bronchoscopy images. Three-dimensional CT can localize tracheobronchial obstructions accurately. Virtual images may eliminate the need for invasive bronchoscopy in patients with questionable foreign body aspiration. Inability to evaluate the mucosal changes remains an important disadvantage of this technique.