The large airways are visible on most good quality chest X-rays. They contain air and so are of lower density (blacker) than the surrounding soft tissues. The trachea branches at the carina into the left and right main bronchi, which can be followed as they branch beyond the hila into the lungs.
Chest X-ray Anatomy
Trachea and major bronchi
Key points
- The large airways contain air and are therefore less dense (blacker) than surrounding tissue
- The trachea should be central
Normal chest X-ray
Hover on/off image to show/hide findings
Tap on/off image to show/hide findings
Normal chest X-ray
- The trachea and bronchi are visible - branching at the carina
- The trachea passes to the right of the aorta and so may be slightly off mid-line to the right
- Highlight these structures by hovering the mouse over the image (mobile devices - tap on/off image)
Assessing the airways
Start your assessment of every chest X-ray by looking at the airways. The trachea should be central or slightly to the right at the level of the aortic knuckle.
If the trachea is deviated, it is important to establish if this is because of patient rotation or if it is due to pathology. If the trachea is genuinely deviated you should then try to decide if it has been pushed or pulled by a disease process.