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.