Bronchopulmonary Segment

Bronchopulmonary Segment :

Intro : 

• Each Tertiary bronchus enters into the one bronchopulmonary segment of the lungs .
• These are well defined anatomic, functional, and surgical sector of the lung.
• A bronchopulmonary segment is independent unit of the lung. 
• i.e. is bronchopulmonary segment is aerated by an indepent segmental bronchus, supplied by independent branch of pulmonary artery but the pulmonary vein is intersegmental .
• 
• A bronchopulmonary segment is a portion of lung supplied by a specific segmental bronchus and arteries.
• These arteries branch from the pulmonary and bronchial arteries, and run together through the center of the segment.
• The segments are separated from each other by layers of connective tissue that forms them into discrete anatomical and functional units.
• There are ten bronchopulmonary segment in each lung .
• It is very important to know about the bronchoulmonary segment whenever they are diseased , only the affected bronchopulmonary segment can be removed . 
• Each bronchopulmonary segment is divided into many lobules by connective tissue . 
• 

Right Bronchopulmonary Segment : There are ten bronchopulmonary segments in the right lung : 

 

• Right lung

  • Superior lobe.
    • apical segment.
    • posterior segment.
    • anterior segment.
    • 
  • Middle lobe. 
    • lateral segment.
    • medial segment.
  • Inferior lobe.
  • superior segment.
  • medial-basal segment.
  • anterior-basal segment.
  • lateral-basal segment.  
  • posterior-basal segment.
  
  

Left Bronchopulmonary Segment : Some of the segments may fuse in the left lung to form usually eight to nine segments (four to five in the upper lobe and four to five in the lower lobe.

• Left lung : 

  • Superior lobe
    • apico-posterior segment (merger of "apical" and "posterior")
    • anterior segment
  • Lingula of superior lobe
    • inferior lingular segment
    • superior lingular segment 
    • 
  • Inferior lobe
    • superior segment
    • anteromedial basal segment (merger of "anterior basal" and "medial basal")
    • posterior basal segment
    • lateral basal segment

Clinical Anatomy : 

• Usually the infection of the bronchopulmonary segment remains restricted to it, although tuberculosis and bronchogenic carcinoma may spread from one segment to another.
• Visualising the interior of the bronchi through a bronchoscope passed through the mouth and trachea, procedure is called bronchoscopy.
• The carina of the trachea is a hook shaped process projecting backward from the lower margin of lowest tracheal ring. It helps to divide trachea into two primary bronchi. Right bronchus makes an angle of 25°, while left one makes an angle of 45°.
• Apical segment of lower lobe is the most dependent bronchopulmonary segment in supine position .Foreigen bodies are likely to be lodged here .