How can a radiolucent airway-obstructing foreign body be identified?

Fluoroscopy: The mediastinum moves away from the side of obstruction on expiration because of air trapping.
Lateral decubitus film: Normally, the dependent side hypoaerates but stays hyperaerated with a foreign body.
Inspiratory and expiratory filmss (older child): The expiratory films will show air trapping on the affected side.
Chest CT: The foreign body may be visible on CT; use caution with the radiation dose.