Usefulness of the 3-dimensionally reconstructed computed tomography imaging for diagnosis of the site of tracheal injury (3D-tracheography)

Abstract

Computed tomography (CT) has not been considered useful for early diagnosis of traumatized patients who could hardly hold their breath, particularly patients with tracheal injuries. However, the recent development of spiral CT has made it possible to acquire contiguous patient data, which eliminates the respiratory misregistration. Air is easily differentiated from surrounding tissues by striking contrast, and the trachea can therefore be well displayed by three-dimensional (3D)-CT. We consider that it is possible to show tracheal injury by 3D-CT. The aim of this study is to clarify the usefulness of 3D-CT for detecting the injury site of blunt tracheal injuries. The study was carried out in hemodynamically stable patients who were suspected of having tracheal injury based on clinical manifestations such as hemoptysis, or cervical subcutaneous, deep cervical, or mediastinal emphysema. Repeated bronchoscopy confirmed tracheal injury. The virtual images of the 3D-CT (3D-tracheography) were compared with the direct images of bronchoscopic findings. Five cases were examined. In patients with tracheal injury, bronchoscopy revealed laceration of the tracheal lumen or disruption and dislocation of the tracheal cartilage, partially coated by mucus and clot, findings that confirmed the diagnosis of tracheal injury. The virtual images of the 3D-tracheography clearly showed the injury as a defect in the tracheal wall or a depression in the wall. The site and size of injury shown in the 3D-tracheography were comparable with those detected by bronchoscopy. We succeeded in detecting tracheal injuries by 3D-CT imaging, the virtual images of which were comparable with the bronchoscopic findings. 3D-tracheography is a useful method for diagnosing the site and form of tracheal injury in hemodynamically stable patients.