What is the role of plain radiography in patients with foreign bodies in the gastrointestinal tract?

Foreign bodies (FBs) in the gastrointestinal (GI) tract can show a wide range of clinical manifestations ranging from spontaneous evacuation to severe complication. Plain radiography is a straightforward and important initial imaging modality in cases of FB ingestion or insertion and is also helpful for follow-up purposes. Careful evaluations of the plain radiographs can determine the presence and nature of FBs, and help predict their precise locations and facilitate risk assessment. In this review, a wide variety of FBs in the GI tract are illustrated, and the role of plain radiography in patient management is discussed.