CASE 17416 Published on 24.09.2021

How to diagnose a button battery ingestion with two signs


Paediatric radiology

Case Type

Clinical Cases


Ferrando Blanco, David; Riaza Martín, Lucía; Piqueras Pardellans, Joaquim; Salgado Barriga, Roberto; Ochoa Sambrizzi, Nicolás Andrés

Department of Pediatric Radiology, Hospital Universitari Vall d'Hebron, Barcelona, Spain


1 year, female

Area of Interest Mediastinum, Paediatric, Thorax ; Imaging Technique Conventional radiography, CT-Angiography, MR
Clinical History

A 1-year-old girl was brought to the emergency room because of drooling and vomiting. The physical exam was anodyne. Nobody witnessed the ingestion of a foreign body. No relevant pathologic antecedents nor medications were referred. A chest and abdominal radiographs were performed.

Imaging Findings

Abdominal radiograph was normal. On frontal chest radiograph a round, 23-mm diameter, radiopaque foreign body was found, located in the theorical position of distal oesophagus. The foreign body had a double rim sign/halo sign, which consisted of the presence of two concentric circles, which lead to the diagnosis of ingestion of button battery. Endoscopic extraction confirmed the diagnosis.

Because oesophagus wall injury was found during endoscopy, further imaging techniques were performed to detect severe complications. During the hospitalisation, the patient had a CT angiography (one day after the endoscopy) and a chest MRI (one week after) and distal oesophagus dilation. Both studies showed oesophageal wall thickening, hyperhaemia (increased enhancement due to increased vascularity) and oedema (shown as T2-hyperintensity on MR).


Foreign body ingestion is a relative frequent situation among paediatric patients. Coins (70%) are the most frequent foreign body recovered on endoscopies followed by button batteries (2-6%). Clinically patients can present with choking, vomiting, dysphagia or be asymptomatic, and physical examination can reveal tenderness to palpation of abdomen, chest or throat or be normal [1].

A chest radiograph is the first examination that should be done and recognizing a button battery on it is essential since this changes the algorithm for management, being indicated an emergent endoscopic removal if it is suspected to be in the oesophagus. Severe complications can occur even in less of 2 hours (between ingestion and extraction). There has been a dramatic rise in morbi-mortality associated with button battery ingestion due to an increased diameter and an increased use of lithium type battery button [2].

The main differential diagnosis of button battery are coins because both are round, with similar diameter and radiopaque. The two signs that shows button battery, but no coins are:

  • Double rim/halo sign (frontal/AP view). Button batteries are composed of two metallic disks, the anode (the smallest) and the cathode (the largest). This sign consists of the presence of two concentric circles and corresponds to the two metallics discs.
  • Step-off sign (lateral view). This sign corresponds to the different calibre of the two discs.

Causes of false-negatives of these signs are small button batteries; whereas, a false-positive is represented by the impaction of two coins of a similar size in a juxtaposed position [3].

If oesophageal injury is identified on endoscopy, a CT angiography or an MRI should be performed to detect severe complications. The most important mechanism of injury is electrolytic production of alkaline fluid because of a local circuit due to the contact of anode and cathode with oesophageal walls. The side which contacts with the anode is more affected than the other side. If the anode contacts with the anterior oesophageal wall there is more risk of developing a tracheo-oesophageal fistula; whilst, if it contacts with the posterior wall there is more risk of oesophago-aortic fistula or spondylodiscitis. Other complications are oesophageal diverticulum, oesophageal and tracheal stenosis, mediastinitis, vocal cord paralysis and systemic lithium absorption [3,4].

It is important the recognition of the halo (frontal) and step-off signs (lateral) in chest radiographs to differentiate a button battery from a coin.

Differential Diagnosis List
Ingestion of a button battery and impaction in the distal oesophagus
Oesophageal impaction of coins
Final Diagnosis
Ingestion of a button battery and impaction in the distal oesophagus
Case information
DOI: 10.35100/eurorad/case.17416
ISSN: 1563-4086