Right lung — superior lobe

Function

The right lung's upper lobe rises above the horizontal fissure to the lung apex — the apex rising above the medial clavicle into the root of the neck, grooved by the subclavian artery.

Three segments (apical, anterior and posterior). When upright, the apex is relatively under-perfused, giving it the highest ventilation/perfusion ratio and oxygen tension — conditions that favour reactivation tuberculosis.

Blood supply

Right pulmonary artery's upper lobe branches.

Nerve supply

Right vagal and sympathetic pulmonary plexuses.

Clinical relevance

Apical TB

Mycobacterium tuberculosis reactivates in the apex's oxygen-rich soil — the upper-lobe cavity of consumption.

Pancoast tumour

Apical lung cancers invade the brachial plexus and sympathetic chain — shoulder pain, hand wasting and Horner syndrome.

Related conditions

• Chronic obstructive pulmonary disease
• Lung cancer
• Tuberculosis
• Pneumothorax (collapsed lung)
• Cystic fibrosis