CAMRT Radiography Practice Exam

To check if a foreign body is in the lungs as opposed to the esophagus, which view is best?

1. PA Inspiration

2. PA Expiration

3. Lateral View

4. AP View

The correct answer is: PA Expiration

The best choice for checking if a foreign body is in the lungs rather than the esophagus is the PA Expiration view. This is primarily because, during expiration, the lungs are relatively smaller and less inflated, making it easier to identify foreign bodies that may be lodged within lung structures. The contrast between air-filled lung tissue and any potential foreign objects becomes more pronounced, allowing for better visualization of the foreign body. Additionally, when considering the presence of foreign bodies, the PA view during expiration can help to differentiate between an aspiration event (which would likely affect the lungs) and an object located in the esophagus, as the positioning of the structures within the thorax changes with breath cycles. While the PA Inspiration view shows the lungs fully expanded and can sometimes obscure foreign objects, the Lateral View and AP View tend to provide less optimal information regarding the relationship of the foreign body to the lung fields versus the esophagus. Lateral views can help with additional anatomical orientation, but they are generally less definitive in distinguishing the localization of a foreign body compared to the PA Expiration view.