ABSTRACT
The lungs, the principal organs of respiration, are located on either side of the heart within the thorax. The hilum, or root of the lung, is the pathway through which airways and vessels traverse and communicate with the lungs. The lungs are conical in appearance and take on a shape congruent with surrounding structures (i.e., a concave base due to the adjacent dome of the diaphragm). The right lung is divided into two interlobular fissures into an upper, middle, and lower lobe. The horizontal fissure separates the right upper
of the various bronchopulmonary segments is depicted in Figure 1.3.
