Figure 5. Normal bronchial branching pattern. Coronal multiplanar reformatted image depicts a normal bronchial branching pattern. Note the mild indentation of the trachea by the left aortic arch (Ar). The relationships between the upper lobe bronchi and the pulmonary arteries are well seen. LPA = left pulmonary artery, LUL = left upper lobe, RPA = right pulmonary artery, RUL = right upper lobe.