Bronchi

Name the Segments

2. Findings and Diagnosis

 

Lung	Lobe	Segmental Bronchi	Comments on Anatomic Variations
Right Lung	Upper Lobe	– Apical (B1)	The number and branching pattern of segmental bronchi can vary among individuals.
		– Posterior (B2)	Some segments may be absent or combined, particularly in the left lung.
		– Anterior (B3)
Right Lung	Middle Lobe	– Lateral (B4)	The middle lobe is unique to the right lung and has distinct segmental bronchi.
		– Medial (B5)
Right Lung	Lower Lobe	– Superior (B6)	The superior segment (B6) is well-developed in both lungs.
		– Medial basal (B7)	Medial basal (B7) may be absent or fused with adjacent segments.
		– Anterior basal (B8)
		– Lateral basal (B9)
		– Posterior basal (B10)
Left Lung	Upper Lobe	– Apicoposterior (B1+2)	Apical and posterior segments (B1+2) are often fused in the left lung.
		– Anterior (B3)
	Lingula	– Superior lingular (B4)	The lingula is unique to the left lung and corresponds functionally to the middle lobe in the right lung.
		– Inferior lingular (B5)
Left Lung	Lower Lobe	– Superior (B6)	Similar to the right lung, the superior segment (B6) is well-developed.
		– Anteromedial basal (B7+8)	The medial and anterior basal segments (B7+8) are often combined.
		– Lateral basal (B9)
		– Posterior basal (B10)

Anatomic Variations

• Left lung differences: The apical (B1) and posterior (B2) segments are commonly fused into a single “apicoposterior” segment (B1+2).
• Lingula: The lingular segments (B4, B5) in the left lung are functionally analogous to the middle lobe in the right lung.
• Basal segment fusion: The medial (B7) and anterior basal (B8) segments are often combined into a single “anteromedial basal” segment (B7+8) in the left lung.
• Segmental variations: Some individuals may have absent, fused, or supernumerary segments, leading to minor differences in bronchial anatomy.

Memory Image
Segmental and Subsegmental Anatomy of the Lung