Segmental bronchi undergo further branching and a decrease in diameter to the level of the bronchioles. Graphic of posterior view of the tracheobronchial tree depicts color-coded segmental bronchial origins that correspond to color-coded lung segments. First of 3 normal axial T1 MR images shows the normal hilar anatomy.
The bronchi (or bronchus) are the air passages into the lungs that begin at the end of the trachea. There are two bronchi, one for each lung. The bronchus divide into smaller branches known as segmental bronchi, which divide again into bronchioles,
Bronchopulmonary Segments. A bronchopulmonary segment is a division of the lung; in fact, these segments are the largest subdivisions of a lung lobe. In other words, lung lobes are subdivided into bronchopulmonary segments that are each supplied by a tertiary (segmental) bronchus.