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Three Part Question

In [patients who might have a fish bone in the throat] is [an x-ray of the neck] indicated to [diagnose and locate the bone]?

Clinical Scenario

A 40 year old man attends the emergency department having recently eaten fish. He feels that a bone has got stuck in his throat. Examination of the oropharynx does not reveal a bone. You wonder whether an x-ray would aid diagnosis.

Search Strategy

Medline 1966-06/99 using the OVID interface.
({exp fishes OR fish$.mp} AND {exp bone and bones OR bone$.mp} OR fishbone$) AND (exp pharynx OR throat.mp OR exp oropharynx OR oropharynx.mp}.

Search Outcome

42 papers found of which 37 irrelevant and 2 of insufficient quality for inclusion. The three remaining papers are shown in the table.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Ngan JH et al, Hong Kong, 1990	310 of 358 patients over the age of 12 years complaining of fishbone ingestion	Prospective diagnostic	Sensitivity	32%
			Specificity	91%
			Positive predictive value	66%
Evans RM et al, Hong Kong, 1992	100 neck radiographs of patients with known fish bones mixed with 100 normal control films. Each assessed by two radiologists	Diagnostic	Sensitivity	25.3%
			Specificity	86.3%
			Positive predictive value	72.7%
Sundgren PC et al, Sweden, 1994	42 consecutive patients with fishbone ingestion	Retrospective diagnostic	Sensitivity	28.6%	Small numbers
			Specificity	87.5%

Comment(s)

While there are many studies that show that fish bones can be seen on x-ray, the studies in the table show that the clinical utility and accuracy of lateral neck x-rays is poor in the clinical situation.

Clinical Bottom Line

Lateral neck x-rays are not indicated in the emergency department management of suspected fish bone impaction.

References

1. Ngan JH, Fok PJ, Lai EC et al. A prospective study on fish bone ingestion. Experience of 358 patients. Ann Surg 1990;211:459-462.
2. Evans RM, Ahuja S, Rhys Williams S et al. The lateral neck radiograph in suspected impacted fish bones - does it have a role? Clin Radiol 1992;46:121-123.
3. Sundgren PC, Burnett A, Maly PV. Value of radiography in the management of possible fishbone ingestion. Ann Otol Laryngol 1994;103:628-631.