title: The utility of a handheld metal detector in detection and localization of pediatric metallic foreign body ingestion.
abstract: OBJECTIVE
  To test the ability of a handheld metal detector (HHMD) to identify the presence and location of ingested metallic foreign bodies (MFBs) in children.
  
  
  METHODS
  Prospective case series enrolling children suspected of metallic foreign body ingestion presenting to the Emergency Department. Thirty-eight children were enrolled and the HHMD was used to detect the presence and location of a MFB. Results were compared to standard radiographic studies.
  
  
  RESULTS
  Thirty-seven of the 38 ingested foreign bodies were MFBs. Of the 37 MFBs, the HHMD positively identified 33, and 4 were missed by HHMD but identified on radiography. When positive, the location indicated by HHMD correlated 100% with radiograph. There were 33 true positives, 0 false positives, 4 false negatives, and 1 true negative. This resulted in a sensitivity of 89% (95% CI of 75%-96%) and specificity of 100% (95% CI of 2.5%-100%).
  
  
  CONCLUSIONS
  Our study demonstrates the accuracy of HHMD in the identification and localization of metallic foreign bodies. We propose an emergency room foreign body protocol that uses HHMD as an early screening tool in triage in order to expedite the process of obtaining Otolaryngology consultation and potentially shorten the wait time to the operating room or discharge. In instances were outside films are previously performed, HHMD use may be able to minimize the overall radiation exposure to children by obviating the need for repeat radiographs. As the sensitivity is not 100%, a negative HHMD screening does not negate the need for a standard radiograph in order to avoid missed MFBs. HHMD is best suited for detection of coins, which accounts for the majority of the MFB ingestions, and may not be suitable for all metallic objects since the amount of metal may decrease its sensitivity.
authors.affiliation: Rady Children's Hospital San Diego Pediatric Otolaryngology, 3030 Children's Way Suite 402, San Diego, CA 92123, USA; University of California San Diego, Division of Otolaryngology, 200 West Arbor Drive, San Diego, CA 92103, USA. Electronic address: jnation@ucsd.edu.
authors.forename: Javan
authors.initials: J
authors.lastname: Nation
authors.affiliation: Rady Children's Hospital San Diego Pediatric Otolaryngology, 3030 Children's Way Suite 402, San Diego, CA 92123, USA; University of California San Diego, Division of Otolaryngology, 200 West Arbor Drive, San Diego, CA 92103, USA. Electronic address: wjiang@rchsd.org.
authors.forename: Wen
authors.initials: W
authors.lastname: Jiang
mesh_terms: D002648:Child; D002675:Child, Preschool; D003938:Diagnostic Techniques, Digestive System / Q000295:instrumentation; D004636:Emergency Service, Hospital; D005188:False Negative Reactions; D005260:Female; D005547:Foreign Bodies / Q000175:diagnosis* / Q000000981:diagnostic imaging; D041981:Gastrointestinal Tract; D006801:Humans; D007223:Infant; D008297:Male; D008670:Metals; D000067716:Point-of-Care Testing; D011446:Prospective Studies; D011859:Radiography; D012680:Sensitivity and Specificity
chemical_list: D008670:Metals
keywords: Handheld metal detector; Metallic foreign body ingestion