Metal detectors: an alternative approach to the evaluation of coin ingestions in children?

Foreign body ingestions constitute a common problem in pediatric emergency medicine. Recent data indicate that, despite current recommendations, most children who ingest coins do not undergo radiologic evaluation. The purpose of this study was to determine the accuracy of a metal detector in locating coins in a model simulating coin ingestions in children. Initially, the distance between the anterior chest wall (ACW) and the esophagus was measured on 17 chest computed tomograms obtained on children between the ages of three months and six years. Subsequently, a distance equal to the mean ACW-to-gastroesophageal junction measurement was marked across the investigator's forearm. A second investigator then attempted to detect the presence of the coin through the forearm by using a Super Scanner (Garrett Security Systems, Inc, Garland, TX) metal detector. The study was conducted in a blinded manner and consisted of 50 attempts equally divided among pennies, nickels, dimes, quarters, and controls (no coin). The accuracy of the metal detector in identifying the presence or absence of coins in our model was 100%. We conclude that the metal detector evaluated by us is highly accurate in identifying coins through human tissues and that it should become a valuable and practical tool in the evaluation of children following a coin ingestion.