Use of plain radiography and computed tomography to identify fish bone foreign bodies

INTRODUCTION: Fish bones are the most common aerodigestive foreign bodies i n adults. Radiographic studies, often ordered for diagnosis, have questiona ble utility. METHODS: With a laryngoscope, bones from 10 fish species were placed in a v ariety of positions in a human head and neck cadaver specimen. Plain films and CT scans were obtained and evaluated by blinded readers. RESULTS: Plain radiography exhibited a sensitivity and specificity of 39% a nd 72%. Cooking did not grossly change radio-opacity. The species of fish a ffected visibility in soft tissue, without correlation to the characteristi c optical density of each species. Bones placed orthogonal to the film in t he vallecula were most readily identified. CT scanning correctly identified 9 of 10 bones. CONCLUSIONS: Plain radiography poorly visualizes fish bone foreign bodies i n soft tissue; visibility varied with fish species, location, and orientati on. CT is the test of choice to radiographically diagnose fish bone impacti ons.