Aortic ostia of the bronchial arteries and tracheal bifurcation: MDCT analysis.

Aim: To explore the anatomical relationships between bronchial artery and tracheal bifurcation using computed tomography angiography (CTA).

Methods: One hundred consecutive patients (84 men, 16 women; aged 46-85 years) who underwent CTA using multi-detector row CT (MDCT) were investigated retrospectively. The distance between sites of bronchial artery ostia and tracheal bifurcation, and dividing directions were explored. The directions of division from the descending aorta were described as on a clock face.

Results: We identified ostia of 198 bronchial arteries: 95 right bronchial arteries, 67 left bronchial arteries, 36 common trunk arteries. Of these, 172 (87%) divided from the descending aorta, 25 (13%) from the aortic arch, and 1 (0.5%) from the left subclavian artery. The right, left, and common trunk bronchial arteries divided at -1 to 2 cm from tracheal bifurcation with frequencies of 77% (73/95), 82% (54/66), and 70% (25/36), respectively. The dividing direction of right bronchial arteries from the descending aorta was 9 to 10 o'clock with a frequency of 81% (64/79); that of left and common tract bronchial arteries was 11 to 1 o'clock with frequencies of 70% (43/62) and 77% (24/31), respectively.

Conclusion: CTA using MDCT provides details of the relation between bronchial artery ostia and tracheal bifurcation.