The use of a metal detector to locate ingested metallic foreign bodies in children

Abstract

Objective - A pilot study to assess whether modern metal detectors can reduce unnecessary radiation in searching for ingested metallic foreign bodies. Methods - Over a one year period, 20 children presenting to an accident and emergency department with suspected metallic foreign body ingestion were studied. Using an Adams Electronics AD 15 metal detector, the radiographer recorded the location of metallic foreign bodies on a pictorial representation of neck, chest, and abdomen. The child then had plain radiographs of abdomen, chest, and neck in sequential order until the foreign body was located. Results - In seven cases neither metal detector nor radiography revealed a foreign body (true negatives). In the remaining 13 cases where metal detection was positive, subsequent radiography or faecal search was also positive (true positives). The 13 foreign bodies were coins (8), gold ring (1), ball bearing (1), screw (1), staple (1), and washer (1). All were in the stomach or proximal small bowel on radiography except for one coin in the right iliac fossa. The detector can demonstrate ingested metallic foreign bodies reliably in children, thereby reducing unnecessary irradiation.