The chest x-ray shows the tubular artery sign, indicating the presence of pneumomediastinum.

The tubular artery sign is seen when streaks of air outline the great vessels of the neck in a patient with pneumomediastinum.

Pneumomediastinum, when seen in the context of chest pain preceded by vomiting, should lead to a high index of suspicion for Boerhaave syndrome or effort rupture of oesophagus. This condition has a high mortality and hence is important to diagnose.

When an oesophageal rupture is suspected, a CT scan of the chest with water soluble contrast swallow can be performed to confirm the diagnosis (depending on institutional guidelines).

This particular patient was admitted and observed as they were stable. A repeat chest x-ray a few days later showed a resolution of the pneumomediatinum.

Reference: https://pubs.rsna.org/doi/full/10.1148/radiographics.20.4.g00jl131043

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