From the Guidelines
For diagnosing a fish bone in the throat, a CT scan is the most recommended imaging method due to its high sensitivity and specificity, especially when plain X-rays are negative or inconclusive. When it comes to identifying fish bones in the throat, the choice of imaging is crucial for accurate diagnosis and timely intervention. The sensitivity of plain X-rays can be as low as 32% for detecting fish bones 1, making them less reliable for this specific purpose.
Key Considerations for Imaging
- Plain X-rays may have a high false-negative rate, especially for certain types of foreign bodies like fish or chicken bones, which can be up to 85% 1.
- Biplanar radiography, including lateral projections, can help differentiate between tracheobronchial and esophageal foreign bodies but still may not be sufficient for small or less radiopaque objects like fish bones.
- Computed Tomography (CT) scans offer a significant advantage with a sensitivity of 90-100% and specificity of 93.7-100% for detecting fish bones 1, making them an essential tool, especially in cases where X-rays are negative but clinical suspicion remains high.
- Contrast swallow studies are not recommended as they can delay other necessary interventions and pose risks such as aspiration in cases of complete esophageal obstruction 1.
Clinical Approach
Given the potential complications of a retained fish bone, such as infection or perforation, prompt and accurate diagnosis is critical. CT scans should be considered the primary imaging modality for adult patients with suspected fish bone ingestion, especially when initial X-rays are negative. This approach ensures that patients receive appropriate and timely care, minimizing the risk of serious complications. Symptoms such as persistent throat pain, difficulty swallowing, or a sensation of something being stuck should prompt immediate medical evaluation.
From the Research
Imaging Options for Fish Bone in Throat
- Lateral soft tissue X-ray: This method has been found to be less reliable, especially because not all fish have radio-opaque bones 2, 3, 4.
- Computed Tomography (CT) scan: CT scan is the preferred modality for imaging fish bone foreign bodies, especially in patients over 40 years old 5.
- Fibreoptic nasendoscopy (FNE): FNE is a more reliable tool for diagnosing and treating fish bone impaction in the oropharynx 2.
- Fluoroscopy: Fluoroscopy can be used to guide the removal of migrating ingested foreign bodies, including fish bones 6.
Limitations of Imaging Studies
- Lateral neck radiographs have limited value in the management of suspected fish bone impaction, with a sensitivity of 51.6% 3.
- Routine radiography for suspected impacted fish bones should be abandoned due to its poor performance, with a sensitivity of 25.3% 4.
- CT scans may not be necessary for patients under 40 years old who present within 24 hours of ingestion, as the probability of esophageal fish bones is low 5.