Relations between the tracheal and pulmonary trunk bifurcations

The bifurcation of the pulmonary trunk and trachea were followed on 52 cases being appreciated on the dissection and corrosion pieces and CT examinations, the arterial bifurcation being made under an very variable angle, its value ranging from 30-1080. In 82% of cases the tracheal bifurcation was done under an acute angle, with lower value than the arterial bifurcation angle. In 41 cases (78.85% of cases) the pulmonary trunk bifurcation is done under the bifurcation of the trachea, at a distance of between 0,4 - 2,8 cm, and in 8 patients (15.38% of the cases) the two bifurcations was located at the same level. Only in 3 cases (5.77% of cases), all on CT angiography, we encountered the pulmonary trunk bifurcation above tracheal bifurcation, with 0.3-0.8 cm, bifurcation of the pulmonary trunk being left lying of the tracheal bifurcation. In these cases, the bifurcation angle of the pulmonary trunk is always greater than the angle of the trachea bifurcation. On the dissected and the corrosion pieces is found that when the bifurcation is situated at different levels, the tracheal one being located cranial, the most commonly between them form a rectangular area: rhombus, more frequently, and rectangular or trapezium and rarely a pentagon or triangle. Any geometric shape to be formed between the two junctions, it is often asymmetric.