Subsegmental bronchus

Subsegmental bronchus refers to the smaller branches of the bronchial tree that extend from the segmental bronchi. Each lung is divided into lobes, and each lobe is further divided into segments. Each segment is served by a segmental bronchus, which further divides into subsegmental bronchi.

Anatomy

The human respiratory system is a complex network of air passages that facilitate the exchange of gases between the body and the environment. The subsegmental bronchi are a crucial part of this system. They are the third level of airway branching in the bronchial tree, following the main bronchi and segmental bronchi.

Each subsegmental bronchus supplies a bronchopulmonary segment, which is the functional unit of the lung. These segments are pyramidal in shape, with the apex pointing towards the root of the lung and the base lying against the pleural surface.

Function

The primary function of the subsegmental bronchi, like all parts of the bronchial tree, is to carry air from the trachea to the alveoli, where gas exchange occurs. They also have a role in the immune defense of the lungs, as they are lined with ciliated epithelial cells that help to remove foreign particles and pathogens.

Clinical significance

Diseases of the subsegmental bronchi can lead to significant respiratory problems. For example, in bronchitis, the lining of the bronchial tubes becomes inflamed, leading to coughing and difficulty breathing. In asthma, the bronchial tubes become narrow and inflamed, leading to wheezing and shortness of breath.

Bronchoscopy is a common procedure used to examine the bronchial tree, including the subsegmental bronchi. It can be used to diagnose and treat conditions such as lung cancer, chronic cough, and infections.

See also

• Bronchus
• Bronchial tree
• Respiratory system