Coin in the Airway: When Hoarseness After “Swallowing a Coin” Is an Airway Emergency

 

How AP and lateral radiographs distinguish airway from esophageal foreign bodies—and why a clinically stable child may still require urgent bronchoscopy.

Executive Clinical Summary

A coin is usually considered a swallowed foreign body. But the clinical problem changes completely when the object is actually in the airway.

A previously healthy boy in his early teens presented after swallowing a coin and continued to experience hoarseness and dysphagia for six hours. His breathing was initially stable, with no stridor or drooling. Chest and neck radiographs, however, demonstrated a round radiopaque foreign body at the level of the subglottic airway.

The decisive issue was therefore not simply identifying a metallic object. It was determining where the object was located.

In this case, the combination of clinical symptoms and radiographic localization supported the diagnosis of airway foreign body aspiration. The subglottic 25-cent coin was subsequently removed under general anesthesia using rigid bronchoscopy and optical forceps.

This case illustrates a fundamental principle of emergency imaging:

After foreign-body ingestion, location is more important than the history of “swallowing.”

A patient who appears clinically stable may still harbor an airway foreign body capable of producing sudden obstruction if the object shifts or airway edema develops.

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Key Clinical Questions

1. How can a coin be distinguished from an airway foreign body on radiographs?
2. Why are both AP and lateral projections important?
3. Can coin orientation reliably determine whether the object is in the esophagus or airway?
4. When is CT useful in suspected pediatric foreign body aspiration?
5. Why can a patient with an airway foreign body initially have normal breathing?
6. When should rigid versus flexible bronchoscopy be considered?
7. What role could AI play in detecting airway foreign bodies?
8. How should an emergency imaging workflow be designed to minimize diagnostic delay?

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Introduction

Foreign body aspiration is an important pediatric emergency because the clinical presentation can range from transient cough to sudden complete airway obstruction.

The diagnosis becomes particularly challenging when the patient does not look critically ill.

A child may be breathing comfortably, oxygenating adequately, and speaking normally enough to reassure the initial examiner. Yet an object lodged in the larynx, subglottic airway, or trachea can remain mechanically unstable. A small change in position or progressive mucosal edema may substantially alter the effective airway diameter.

This is why imaging interpretation cannot be separated from the clinical history.

The present case is particularly instructive because the history initially suggests a familiar problem: a child swallowed a coin.

The radiologist's question must be different:

Did the coin enter the esophagus, or did it enter the airway?

That distinction changes the urgency, the procedural pathway, and the potential consequences.

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Clinical Hook: The Patient Was Breathing Normally

The patient was a healthy boy in his early teens who reported swallowing a coin approximately six hours before presentation.

He continued to experience:

• Hoarseness
• Dysphagia

Importantly, he had:

• No obvious respiratory distress
• No stridor
• No drooling
• Apparently normal breathing

The radiographs nevertheless demonstrated a radiopaque round foreign body in the region of the subglottic airway.

This is precisely the type of presentation in which clinical reassurance can become dangerous.

Normal breathing does not prove that an airway foreign body is harmless.

It only tells us that severe airway obstruction has not yet developed.

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Learning Objectives

By the end of this article, readers should be able to:

1. Recognize the radiographic appearance of a metallic airway foreign body.
2. Distinguish an airway foreign body from an esophageal coin using AP and lateral imaging.
3. Understand why coin orientation is useful but not definitive.
4. Recognize the limitations of normal chest radiography in radiolucent aspiration.
5. Understand when CT can contribute to the evaluation of suspected aspiration.
6. Appreciate the clinical role of rigid and flexible bronchoscopy.
7. Identify practical opportunities and limitations for AI-assisted detection.

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Anatomy Review

Understanding the anatomy is essential because the same foreign object can have dramatically different clinical implications depending on its location.

The relevant airway pathway is:

Larynx → subglottic airway → trachea → main bronchi → lobar bronchi → segmental bronchi

The subglottic region is particularly important because it represents a relatively narrow portion of the airway.

An object occupying a substantial fraction of this lumen may produce relatively little respiratory compromise initially but can become dangerous if:

• The object moves
• Mucosal edema develops
• Inflammation increases
• Granulation tissue forms
• Secretions accumulate

Once an object passes farther into the tracheobronchial tree, its clinical behavior changes again.

In older children, the larger airway permits foreign bodies to reach the trachea or main bronchi. The right main bronchus is also anatomically more favorable for foreign-body entry because of its relatively wider and more vertical course.

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Case Presentation

Patient Profile

Age: Early adolescence
Sex: Male
Clinical status: Previously healthy

History

The patient reported swallowing a coin.

Approximately six hours later, hoarseness and dysphagia persisted.

Clinical Examination

Breathing was reported as normal.

Stridor and drooling were absent.

Imaging

Chest PA and neck/chest lateral radiographs demonstrated a radiopaque round metallic foreign body in the region of the subglottic airway.

Final Diagnosis

Airway foreign body aspiration involving the subglottic region.

Treatment

Under general anesthesia, rigid bronchoscopy was performed. A 25-cent coin was identified in the subglottic region and removed with optical forceps.

The case therefore demonstrates a direct transition from:

Clinical history → radiographic localization → airway diagnosis → bronchoscopic removal.

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Imaging Features

Why Plain Radiography Matters

Coins are radiopaque and are therefore readily visible on conventional radiographs.

For suspected pediatric ingested or aspirated foreign bodies, radiography remains an important first-line imaging tool. The current ACR Appropriateness Criteria classify chest and neck radiography as usually appropriate for initial evaluation of a child with suspected ingested or aspirated foreign body.

The key is not simply to identify the object.

The radiologist must determine:

1. What is the object?
2. Where is it?
3. Is it in the airway or esophagus?
4. At what anatomical level?
5. Does the imaging agree with the symptoms?

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SOURCE FIGURE 1 — Chest PA Radiograph

Figure 1. Chest PA radiograph demonstrating a radiopaque round foreign body in the upper central airway region.

Radiologist Interpretation

A round, highly radiopaque metallic foreign body is projected over the upper airway.

Its central location raises the possibility of a laryngeal, subglottic, or tracheal foreign body.

The AP projection alone, however, should not be used to make a definitive distinction between airway and esophageal location.

Clinical Significance

The combination of persistent hoarseness and a radiopaque object projected over the airway should prompt immediate attention to the possibility of airway aspiration.

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FIGURE 2 — Lateral Radiograph

Figure 2. Lateral radiograph demonstrating the metallic foreign body in the anterior airway region at the subglottic level.

Radiologist Interpretation

The lateral projection localizes the round metallic foreign body to the anterior airway region rather than the posterior esophageal compartment.

This is a critical contribution of the lateral image.

Clinical Significance

When a metallic foreign body is located at the subglottic airway, the clinical priority changes from routine management of an ingested object to airway protection and removal.

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The Coin Orientation Sign: Useful but Not Absolute

The classic teaching is:

Location	AP Projection	Lateral Projection
Esophageal coin	Usually en face	Usually profile
Airway coin	Usually edge-on	Usually en face

This is an extremely useful mental model.

But it should not become a diagnostic shortcut.

A coin in the esophagus can occasionally assume an atypical orientation. Published radiologic evidence has specifically documented sagittally oriented esophageal coins, demonstrating that orientation alone cannot establish airway location.

Therefore:

Coin orientation is a clue, not a diagnosis.

The radiologist should integrate:

• Object orientation
• Anatomic level
• Relationship to the trachea
• Relationship to the esophagus
• AP and lateral projections
• Clinical symptoms

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Differential Diagnosis

Diagnosis	Key Imaging Finding	Clinical Clue	Differentiating Point
Airway coin	Metallic object in larynx/subglottic airway/trachea	Hoarseness, cough, stridor or respiratory symptoms	Airway localization on AP + lateral
Esophageal coin	Round metallic object in esophagus	Dysphagia, drooling, chest discomfort	Posterior relationship to airway
Button battery	Round metallic object, possible halo/double-rim and step-off	Dysphagia, drooling, chest symptoms	Halo on AP and step-off on lateral may help
Radiolucent airway foreign body	No directly visible object	Cough, wheeze, recurrent symptoms	Indirect signs such as air trapping or atelectasis
Laryngitis/croup	No metallic foreign body	Hoarseness, infectious symptoms	Clinical context and absence of foreign body
Other metallic foreign body	Radiopaque object	Variable	Object morphology and history

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Button Battery: The Critical Mimic

A round metallic object should never automatically be labeled a coin.

A button battery can closely mimic a coin on radiography, but the clinical consequences can be substantially more serious when the battery is lodged in the esophagus.

Radiographic clues include:

• A double-rim or halo appearance on the AP projection
• A step-off appearance on the lateral projection

These findings can help distinguish a button battery from a solid coin, although they are not infallible.

The distinction matters because an esophageal button battery can cause severe tissue injury within a short period of time.

Therefore, when the identity of a round metallic object is uncertain, the imaging interpretation should not create false reassurance.

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Clinical Presentation

Symptoms of pediatric foreign body aspiration are highly variable.

Symptom	Potential Clinical Implication
Sudden cough	Important initial clue to aspiration
Hoarseness	Suggests laryngeal or upper-airway involvement
Stridor	Possible upper-airway obstruction
Wheezing	May occur with bronchial foreign body
Dysphagia	Requires differentiation among pharyngeal, laryngeal, esophageal and airway causes
Drooling	May indicate esophageal obstruction or significant upper-airway disease
Dyspnea	Suggests more significant airway compromise
Cyanosis	Warning sign of severe obstruction
Fever	May occur with prolonged retained foreign body and secondary infection

The present case is important precisely because the patient lacked several dramatic respiratory signs.

The absence of stridor or respiratory distress should not override an imaging finding that localizes a foreign body to a potentially dangerous airway segment.

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Why a Normal Chest X-Ray Does Not Exclude Foreign Body Aspiration

Metallic objects are usually visible.

Many organic airway foreign bodies are not.

Examples include:

• Peanuts
• Nuts
• Seeds
• Food particles
• Some plastic objects

In these situations, radiographs may demonstrate only indirect findings such as:

• Unilateral hyperinflation
• Air trapping
• Atelectasis
• Asymmetric lung translucency
• Recurrent focal pneumonia
• Localized emphysematous change
• Mediastinal shift

Thus:

A normal radiograph does not automatically exclude airway foreign body aspiration.

Modern pediatric imaging reviews emphasize that radiographs remain central to initial localization, but radiologists must recognize that many aspirated objects are radiolucent.

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CT: When Does It Add Value?

CT is not automatically the next step for every child with suspected foreign body aspiration.

In a patient with a clearly visible airway foreign body and clinically meaningful symptoms, additional CT should not unnecessarily delay definitive removal.

CT becomes more useful when:

• The object is not clearly localized
• Radiographs are equivocal
• A radiolucent foreign body is suspected
• Complications are suspected
• The airway-esophageal relationship is uncertain
• Long-standing aspiration is suspected
• Atelectasis or focal hyperinflation needs clarification
• Perforation or fistula is suspected

The current ACR criteria identify noncontrast chest CT as usually appropriate when aspiration remains suspected despite negative initial radiographs.

A 2024 systematic review and meta-analysis reported high diagnostic performance for chest CT in pediatric foreign body aspiration, while emphasizing that CT should not replace bronchoscopy when the history and clinical presentation strongly suggest aspiration. 

Another meta-analysis reported similarly high pooled sensitivity and specificity, reinforcing the diagnostic value of CT in selected patients.

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CT Versus Radiography

Modality	Strength	Limitation	Best Clinical Question
AP radiography	Fast, accessible, excellent for radiopaque objects	Limited depth localization	Is a radiopaque foreign body present?
Lateral radiography	Provides anatomic depth information	Still projectional	Airway or esophagus?
Chest CT	Excellent localization and complication assessment	Radiation, time, logistics	Where exactly is the object and what has it caused?
Bronchoscopy	Direct visualization and treatment	Invasive, anesthesia-related risk	Is there an airway foreign body, and can it be removed?

The correct approach is therefore complementary rather than modality-centric.

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Imaging Diagnostic Algorithm

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Treatment: Why Rigid Bronchoscopy Remains Important

The objective in airway foreign body aspiration is not simply to establish the diagnosis.

It is to secure the airway and remove the foreign body safely.

In this case, rigid bronchoscopy under general anesthesia was used to identify and remove the subglottic 25-cent coin with optical forceps.

Rigid bronchoscopy remains particularly valuable because it provides:

• Airway control
• A relatively large working channel
• Direct visualization
• Multiple instrument options
• Foreign-body extraction capability
• Management of secretions or bleeding
• Better control in potentially unstable airway situations

Recent literature continues to support an important role for rigid bronchoscopy in pediatric airway foreign-body management, while recognizing that its role should be interpreted in the context of evolving flexible bronchoscopic techniques. 

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Flexible Bronchoscopy

Flexible bronchoscopy has become increasingly useful, particularly when:

• The foreign body is distal
• The patient is stable
• Diagnostic evaluation is the primary objective
• Access to smaller peripheral bronchi is required

Its limitations may become more important when:

• The foreign body is large
• Immediate airway control is needed
• Significant bleeding is present
• Acute obstruction is developing
• Instrumentation requires a larger working channel

The choice between rigid and flexible bronchoscopy therefore depends on:

• Foreign-body location
• Object size and characteristics
• Patient stability
• Institutional expertise
• Anesthesia capability
• Airway-management resources

Comparative evidence supports a selective rather than universally rigid or universally flexible approach.

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Complications of Delayed Removal

Retained airway foreign bodies may cause both early and delayed complications.

Early complications

• Acute airway obstruction
• Hypoxemia
• Asphyxia
• Mucosal injury
• Bleeding
• Laryngeal edema

Delayed complications

• Granulation tissue
• Recurrent pneumonia
• Bronchitis
• Atelectasis
• Bronchiectasis
• Airway stenosis
• Tracheoesophageal fistula
• Chronic cough

The longer an object remains in the airway, the greater the opportunity for inflammatory changes and secondary complications.

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Why Was This Patient an Emergency Despite Normal Breathing?

This is perhaps the most important clinical lesson.

The patient's respiratory status represented the condition at that moment.

It did not predict what would happen if:

• The coin moved
• Edema increased
• Secretions accumulated
• The airway became more inflamed

A foreign body occupying a narrow airway segment can behave like a mechanical valve.

A small change in position may transform partial obstruction into critical obstruction.

Therefore:

Clinical stability is not equivalent to anatomical safety.

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Airway Foreign Body Versus Esophageal Foreign Body

Feature	Airway Foreign Body	Esophageal Foreign Body
Typical symptoms	Cough, wheeze, hoarseness, stridor	Dysphagia, drooling, chest discomfort
Major immediate risk	Airway obstruction	Mucosal injury/perforation
Radiopaque object	Usually visible	Usually visible
Radiolucent object	May be missed directly	May also be missed
Important imaging	AP + lateral radiographs	AP + lateral radiographs
CT	Selected cases	Selected cases
Definitive procedure	Bronchoscopy	Esophagoscopy/endoscopic management
Emergency priority	Particularly high for laryngeal/subglottic/tracheal location	Depends on object, location and symptoms

This distinction is clinically more meaningful than simply labeling the event as “foreign-body ingestion.”

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Artificial Intelligence Perspective

AI has a realistic role in this clinical scenario, but its most useful function would not be to replace bronchoscopy.

The more practical opportunity is rapid detection and localization.

A computer-vision system could be trained to identify:

• Radiopaque foreign bodies
• Abnormal airway projection
• Possible subglottic location
• Tracheal foreign bodies
• Esophageal foreign bodies
• Airway asymmetry
• Hyperinflation
• Atelectasis
• Indirect signs of radiolucent aspiration

The system could then generate a structured alert such as:

“Possible airway foreign body — review AP and lateral projections.”

That is more clinically useful than simply reporting:

“Foreign body detected.”

Location is the critical information.

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AI Development Pipeline

Important development issues include:

• Dataset quality
• Annotation accuracy
• Class imbalance
• Age distribution
• Object diversity
• Radiographic acquisition differences
• External generalization
• Calibration
• False-negative performance
• False-positive burden
• Domain shift

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AI Failure Analysis

AI-assisted foreign-body detection can fail in several realistic ways.

1. False Negative

A small or poorly positioned foreign body may be missed.

2. Anatomical Mislocalization

The model may detect the object correctly but incorrectly classify it as esophageal rather than airway.

3. Projection Confusion

A metallic object may overlap with normal anatomy and create an incorrect localization.

4. Dataset Bias

A model trained predominantly on young children may perform differently in adolescents.

5. Device and Protocol Variation

Different radiographic systems and acquisition techniques can alter image appearance.

6. False Positive

Normal metallic structures or external objects may trigger an alert.

7. Workflow Failure

An alert may be generated but not seen by the responsible clinician.

8. Automation Bias

Clinicians may accept the AI interpretation without reviewing the images.

For this reason, AI should function as a clinical safety layer, not as an autonomous decision-maker.

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Enterprise Healthcare Workflow

A suspected airway foreign body should not disappear into a generic AI worklist where it receives the same priority as a routine outpatient examination.

The AI platform should support clinical prioritization.

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Enterprise AI Architecture

At hospital scale, the system could incorporate:

• DICOM routing
• AI orchestration
• PACS integration
• RIS integration
• EMR connectivity
• Structured reporting
• Audit logging
• Model monitoring
• Cybersecurity
• Role-based access
• Disaster recovery
• Model version control
• Performance dashboards

A high-risk airway alert should be traceable from image acquisition through AI inference, radiologist review, clinical notification, and final intervention.

This creates an auditable chain:

Image → AI → Radiologist → Clinical Team → Intervention

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Healthcare Economics and ROI Framework

The economic value of AI in this setting should not be reduced to “saving radiologist time.”

A broader framework includes:

Potential benefits

• Earlier recognition
• Reduced diagnostic delay
• Improved worklist prioritization
• Reduced missed findings
• Potential reduction in unnecessary procedures in selected low-suspicion cases
• Improved emergency workflow coordination

Potential costs

• AI licensing
• Integration
• PACS/RIS development
• Infrastructure
• Cybersecurity
• Maintenance
• Staff training
• Validation
• Monitoring

A conceptual ROI equation is:

ROI = (Financial Benefit − Total Cost of Ownership) / Total Cost of Ownership

However, no universal financial return should be assumed.

The real value depends on workflow design, clinical adoption, implementation cost, and measurable patient-care benefits.

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Regulatory Perspective

An AI tool that detects airway foreign bodies would qualify as a medical technology application whose regulatory status depends on its intended use, claims, jurisdiction, and implementation.

Key considerations include:

• Clinical validation
• Performance monitoring
• Human oversight
• Cybersecurity
• Change management
• Post-market surveillance
• Transparency
• Software lifecycle management

Regulatory clearance or approval should never be implied without verification.

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Explainable AI

Explainability is particularly useful for foreign-body detection because the finding itself is spatial.

An AI system should ideally indicate:

• Detection location
• Confidence
• Region of interest
• Suspected airway segment
• Relevant radiographic projection

A heat map alone is insufficient.

A clinically meaningful output might be:

“High-confidence radiopaque foreign body detected in the central upper airway; review lateral projection for airway-versus-esophageal localization.”

The radiologist must still verify the underlying image.

Explainability can improve review efficiency, but it does not guarantee diagnostic correctness.

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Ten Expert Insights

Expert Insight 1 — Radiologist Perspective

The central question is not whether the object is a coin. It is whether the object occupies the airway.

Expert Insight 2 — Emergency Department Perspective

A child with normal breathing may still have a potentially unstable upper-airway foreign body.

Expert Insight 3 — Pediatric Imaging Perspective

AP and lateral projections should be interpreted together rather than treating one projection as definitive.

Expert Insight 4 — Anatomical Perspective

The subglottic region deserves special attention because even a modest amount of additional edema may substantially reduce the remaining airway lumen.

Expert Insight 5 — Diagnostic Perspective

Coin orientation is helpful but cannot replace direct anatomical localization.

Expert Insight 6 — Procedural Perspective

When a foreign body is clearly localized in the airway and symptoms are compatible, diagnostic imaging should not unnecessarily delay definitive airway management.

Expert Insight 7 — CT Perspective

CT is most valuable when radiographs are negative or equivocal and clinical suspicion remains significant, or when complications require additional anatomical assessment.

Expert Insight 8 — AI Perspective

The most useful AI output is not merely “foreign body present.” It is foreign body + anatomical location + urgency.

Expert Insight 9 — Enterprise Perspective

An AI alert has clinical value only if it reaches the right clinician at the right time.

Expert Insight 10 — Patient-Safety Perspective

The safest interpretation is one that integrates history, symptoms, anatomy, imaging and clinical urgency rather than relying on any single sign.

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Clinical Pearls

1. A history of swallowing a coin does not prove an esophageal location.
2. Persistent hoarseness should raise concern for upper-airway involvement.
3. Dysphagia may occur with both airway and esophageal foreign bodies.
4. AP and lateral radiographs provide complementary localization information.
5. Coin orientation is a clue, not an absolute rule.
6. A button battery must be considered when a round metallic object is identified.
7. Radiolucent airway foreign bodies may be invisible on plain radiographs.
8. Normal breathing does not guarantee an anatomically safe airway.
9. CT can be valuable when radiographs are negative or equivocal and suspicion persists.
10. CT should not unnecessarily delay removal of an obvious airway foreign body.
11. Rigid bronchoscopy remains an important therapeutic option in pediatric airway foreign-body management.
12. Flexible bronchoscopy may have an important role in selected stable patients.
13. AI should support rather than replace radiologist interpretation.
14. AI localization may be more clinically valuable than simple object detection.
15. The radiology report should communicate the urgency when an airway foreign body is identified.

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Common Diagnostic Pitfalls

Pitfall 1: “The patient swallowed a coin, so it must be in the esophagus.”

Correction: Always establish anatomical location.

Pitfall 2: Looking only at the AP image

Correction: Review the lateral projection when available.

Pitfall 3: Treating coin orientation as absolute

Correction: Integrate orientation with anatomy and clinical findings.

Pitfall 4: Reassurance from normal breathing

Correction: Assess the potential for positional airway obstruction.

Pitfall 5: Assuming a normal radiograph excludes aspiration

Correction: Consider radiolucent foreign bodies and indirect signs.

Pitfall 6: Ordering CT automatically

Correction: Use CT selectively and do not delay urgent removal.

Pitfall 7: Assuming every round metallic object is a coin

Correction: Consider button battery and other metallic objects.

Pitfall 8: Treating AI output as the diagnosis

Correction: Require radiologist verification and clinical correlation.

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Multimodal Imaging Comparison

Clinical Situation	Preferred Approach
Clearly visible metallic foreign body	Plain radiography with localization
Uncertain airway versus esophageal position	AP + lateral radiographs
Radiograph negative but high clinical suspicion	Consider noncontrast chest CT or bronchoscopy
Suspected complication	CT may provide additional anatomical information
Clearly identified airway foreign body	Expedite specialist evaluation and removal
Suspected radiolucent foreign body	Evaluate indirect radiographic signs and consider CT/bronchoscopy

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AEO: Direct Clinical Answers

What is pediatric foreign body aspiration?

Pediatric foreign body aspiration occurs when an object enters the larynx, trachea, or bronchial tree rather than passing safely into the esophagus. Clinical severity depends on the object's size, location, mobility, and degree of airway obstruction.

What is the key imaging finding in this case?

The key finding is a round radiopaque metallic foreign body localized to the subglottic airway on AP and lateral radiographs.

Can a coin be in the airway after a child says it was swallowed?

Yes. A history of swallowing does not establish the final anatomical location. Imaging must determine whether the object is in the esophagus or airway.

When is CT useful?

CT is particularly useful when initial radiographs are negative or equivocal despite persistent clinical suspicion, especially when a radiolucent foreign body or complication is suspected.

Does normal breathing exclude an airway foreign body?

No. A patient may initially have stable respiration despite an airway foreign body, particularly when the obstruction is incomplete.

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Frequently Asked Questions

1. Why does a coin cause hoarseness?

Hoarseness can occur when a foreign body affects the larynx or subglottic region and interferes with normal airway structures.

2. Is stridor always present?

No. Absence of stridor does not exclude an airway foreign body.

3. Is a coin always radiopaque?

Most conventional coins are readily visible on radiographs.

4. What is the most important radiographic distinction?

The critical distinction is whether the object lies within the airway or esophagus.

5. Why is the lateral view important?

It provides depth information and helps determine the object's relationship to the airway and esophagus.

6. Can an esophageal coin have an unusual orientation?

Yes. Published cases demonstrate atypical sagittal orientation of esophageal coins.

7. Why is a button battery dangerous?

An esophageal button battery can produce significant tissue injury and requires urgent recognition and management.

8. Does a negative X-ray rule out aspiration?

No. Radiolucent objects may not be directly visible.

9. Does CT replace bronchoscopy?

No. CT can assist diagnosis in selected cases, but bronchoscopy remains an important diagnostic and therapeutic procedure. 

10. Can AI diagnose airway foreign bodies?

AI can potentially assist detection and prioritization, but clinical diagnosis should remain under appropriate professional oversight.

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Quiz

Question 1

A boy develops persistent hoarseness after reporting that he swallowed a coin. AP and lateral radiographs show a metallic foreign body in the subglottic airway. What is the most appropriate interpretation?

① Routine esophageal coin
② Gastric foreign body
③ Airway foreign body requiring urgent specialist evaluation
④ Normal variant
⑤ Laryngitis

Correct Answer: ③

Explanation: The combination of symptoms and subglottic localization strongly supports an airway foreign body.

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Question 2

Which statement about coin orientation is most accurate?

① Orientation always determines the anatomical location
② A sagittal coin is always in the trachea
③ AP and lateral orientation can provide useful information but must be interpreted with anatomy
④ The lateral image is unnecessary
⑤ Orientation has no diagnostic value

Correct Answer: ③

Explanation: Orientation is useful but not absolute. Atypical esophageal coin orientations have been documented. 

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Question 3

Which alternative should be considered when a round metallic object is seen in a child?

① Button battery
② Pulmonary edema
③ Pneumothorax
④ Pleural effusion
⑤ Cardiomegaly

Correct Answer: ①

Explanation: Button batteries can mimic coins and may demonstrate halo or step-off signs. 

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Question 4

A child has a convincing aspiration history, but the chest radiograph is negative. What is the most appropriate principle?

① Aspiration is excluded
② Discharge automatically
③ Consider further evaluation because radiolucent objects may be missed
④ Repeat the radiograph after one month
⑤ Assume asthma

Correct Answer: ③

Explanation: A normal radiograph does not exclude aspiration, particularly with radiolucent foreign bodies.

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Conclusion

This case begins with a deceptively simple statement:

“The child swallowed a coin.”

But the radiologic problem is not simply foreign-body identification.

It is foreign-body localization.

A coin in the esophagus and a coin in the airway are fundamentally different clinical problems.

The patient in this case had persistent hoarseness and dysphagia but no stridor or obvious respiratory distress. The radiographs demonstrated a metallic foreign body at the subglottic airway, changing the clinical interpretation from presumed ingestion to airway aspiration.

The case reinforces three principles:

Where is the object?

Does the imaging agree with the clinical presentation?

Could the airway become compromised even if the patient is currently stable?

AP and lateral radiographs remain valuable because they provide complementary localization information. Coin orientation can guide interpretation, but it should never substitute for anatomical analysis. When radiographs are negative or equivocal despite significant clinical suspicion, CT can provide additional diagnostic information, while bronchoscopy remains central when an airway foreign body requires direct evaluation and removal.

The future role of AI is promising, particularly for rapid detection, anatomical localization, and worklist prioritization. But AI should strengthen the clinical pathway—not replace the radiologist, bronchoscopist, or emergency team.

Ultimately, the most important lesson is simple:

A foreign body is not defined by what the patient thinks happened. It is defined by where the object actually is.

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Key Takeaways

• A swallowed coin can enter the airway.
• Persistent hoarseness is an important clue to upper-airway involvement.
• Normal breathing does not exclude a dangerous airway foreign body.
• AP and lateral radiographs should be interpreted together.
• Coin orientation is helpful but not absolute.
• Button battery should remain an important differential diagnosis.
• Radiolucent foreign bodies may be missed on radiographs.
• CT has a selective but important role when radiographs are negative or equivocal.
• CT should not delay removal of an obvious clinically significant airway foreign body.
• Rigid bronchoscopy remains an important treatment modality.
• AI may improve detection and prioritization but requires human oversight.
• The most important radiologic question is often not “What is it?” but “Where is it?”

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References

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2. Brown MC, Powers A, Trope M, Jacobs I. “Airway Foreign Bodies.” Otolaryngologic Clinics of North America. 2026. DOI: 10.1016/j.otc.2026.03.004.
3. Keil O, Huzhva Y, Rigterink V, et al. “Rigid and Flexible Bronchoscopy for Foreign Body Removal in Children: Complications, Risk Factors and Anesthetic Management.” Pediatric Pulmonology. 2025;60(8):e71261. DOI: 10.1002/ppul.71261. (PubMed)
4. Safia A, Abd Elhadi U, Bader R, et al. “Flexible versus Rigid Bronchoscopy for Tracheobronchial Foreign Body Removal in Children: A Comparative Systematic Review and Meta-Analysis.” Journal of Clinical Medicine. 2024;13(18):5652. DOI: 10.3390/jcm13185652. (PubMed)
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