Multislice Computed Tomography Assessment of Tracheobronchial Patterns in Partial Anomalous Left Pulmonary Artery.

Objective: The aim of this study was to present relationship between partial anomalous left pulmonary artery (PALPA) and the tracheobronchial tree and patterns of the tracheobronchial tree assessed by multislice computed tomography (MSCT).

Methods: Nine patients were assessed by MSCT. The relationships between the tracheobronchial tree and PALPA and different tracheobronchial patterns, location of tracheobronchial stenosis, severity of stenosis, and associated cardiac defects were evaluated. The results of MSCT for these patients were compared with the operative findings.

Results: The anatomy of PALPA was clearly identified by MSCT in all 9 patients. Three relationships between PALPA and the tracheobronchial tree were noted. In addition, 3 patterns of tracheobronchial tree anatomy were also demonstrated. The PALPA arose from the right pulmonary artery, forming a pulmonary sling (n = 2). The PALPA, which arose from the proximal right pulmonary artery, went below the tracheal bifurcation and passed anterior (n = 1) or inferior-anterior (n = 6) to the proximal left main bronchus. Three patterns of the tracheobronchial tree were presented with normal (n = 5), normal pattern with right tracheal bronchus (n = 3), and bridging bronchus (n = 1). The rate of tracheobronchial stenosis was 56% (5/9).Five patients underwent operation, and at that time, the relationship between PALPA and the tracheobronchial tree defined on MSCT was confirmed.

Conclusions: The PALPA can be associated with tracheobronchial anomalies and airway compression depending on its orientation to the airway. Noninvasive imaging modalities such as MSCT will be helpful for making further management decisions.