RD7.5 | Imaging in Foreign Body Aspiration — Summary & Reflection

KEY TAKEAWAYS

Imaging in Foreign Body Aspiration — Key Points

• The cardinal rule: a NORMAL chest radiograph does NOT exclude an inhaled foreign body. Most paediatric aspirated objects are organic and radiolucent and cast no shadow.
• History drives the pathway: a convincing choking episode is itself an indication for definitive evaluation, whatever the film shows.
• Imaging strategy (ALARA): frontal chest radiograph first-line; add expiratory or lateral-decubitus views to unmask ball-valve air-trapping (decubitus for the uncooperative toddler); fluoroscopy for dynamic assessment; CT only in selected equivocal cases.
• Direct sign: a radio-opaque object seen directly (the easy minority).
• Indirect signs of a radiolucent object: unilateral hyperinflation/air-trapping (mediastinum shifts AWAY from the obstructed side on expiration), atelectasis/collapse (mediastinum shifts TOWARDS the affected side), and obstructive/recurrent pneumonia in one location.
• Management: bronchoscopy is the definitive diagnostic AND therapeutic step — proceed when suspicion is high regardless of a normal radiograph; remove the object even when pneumonia is being treated; do not be reassured by a normal film.
• Paediatric principle: children are more radiosensitive — choose the few useful low-dose views and avoid reflex repeat imaging once the decision to scope is made.

REFLECT

On your next paediatric or ENT/respiratory posting, look for a child investigated for possible aspiration and trace the reasoning: was the choking history taken seriously, or was a normal film treated as the end of the story? Ask the senior how they decide between observation, special radiographic views, and going straight to bronchoscopy. Watch what happens when the X-ray is normal but the history is strong — the right answer is uncomfortable, because it means scoping a well-looking child on the strength of a story. Internalising that 'a normal film never clears a choking history' is the habit that will, one day, save a child you might otherwise have sent home.