How is the type of oesophageal atresia (presence of a distal fistula) determined on plain X-ray?

A chest and abdominal X-ray with the nasogastric tube in place shows gas in the bowel below the diaphragm if a distal tracheo-oesophageal fistula is present, whereas a gasless abdomen indicates no distal fistula (pure atresia).

Clinical relevance. The bowel gas pattern tells the surgeon whether a distal fistula needs ligation and predicts the gap length.

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Determining the type of oesophageal atresia

The five anatomical types (A-E) differ in whether and where a fistula connects the trachea to the oesophagus. The distal fistula is the clinically important variable because it determines whether swallowed air reaches the gut.

The X-ray sign

• The plain film is taken AP with the nasogastric tube passed as far as it will go (coiling in the upper pouch).
• Gas in the bowel means air has tracked from the trachea through a distal fistula into the stomach and intestine - the common type (C).
• A gasless abdomen means no distal fistula (pure atresia, type A), and the gap between pouches is usually long.

Confirm, type, and screen

Aim	Test
Confirm	NG tube arrests; coiled in pouch on X-ray
Type	Bowel gas pattern on the same film
Associations	2D echo, renal USS, chromosomal study, spinal X-ray