Lung Lobes: Right Has Three, Left Has Two – Anatomy Explained

Correct Lung Lobe Anatomy

The original statement ("Both lungs have three lobes") is incorrect.

Right Lung – Three Lobes

• Upper lobe – separated by horizontal (minor) fissure
• Middle lobe – unique to right lung; separated by oblique (major) fissure
• Lower lobe

Left Lung – Two Lobes

• Upper lobe – includes lingula (homolog of middle lobe)
• Lower lobe

Separated by a single oblique fissure.

Why the Difference?

The left lung accommodates the heart (cardiac notch). The lingula serves as the functional equivalent of the right middle lobe.

Clinical Relevance

• Lobar pneumonia, segmental resection, and bronchoscopy navigation depend on accurate lobar anatomy.
• Right middle lobe syndrome (atelectasis) is a distinct clinical entity.
• Left upper lobe tumors may involve the lingula.

Additional Structures

• Right lung: 10 bronchopulmonary segments
• Left lung: 8–9 segments (apicoposterior segment often fused)