THE RADIO-OPACITY OF FISHBONES - A CADAVERIC STUDY

Lateral neck radiographs performed to localize impacted fishbones have a low sensitivity. The differing radio-opacities of the bones of vari ous fish species may be a reason for this. A cadaver head and neck and the rib bones of 10 species of fish were used in this study. A laryng oscope was used to introduce a fishbone into the vallecula and then in to the hypopharynx of the cadaver. A lateral radiograph was taken in e ach case. Ten control films were taken. The radiographs were independe ntly reviewed by a consultant radiologist and otolaryngologist. The pr esence and position of any bone seen was noted. There was no inter-obs erver variation. All species of fishbone were visible. One bone was no t seen by either observer. Visualization of fishbones is more dependen t on position than their degree of radio-opacity. Routine radiography is recommended.