Esophageal duplication

Duplication of the oesophagus has a range of macroscopic appearances, ranging from complete (which is very rare) to partial (cystic duplication-oesophageal duplication cyst). It is the second most common gastrointestinal tract duplication after that of the ileum.

Epidemiology

A complete duplication is a rare malformation, and is also often associated with a gastric duplication (also rare). A partial duplication is more common. As a congenital abnormality, if symptomatic, it is usually identified soon after birth. 

Clinical presentation

Presentation of large duplication cysts is usually in the newborn or infant, with symptoms referable to pressure on the adjacent lung or oesophagus, leading to:

• respiratory difficulties
• dysphagia
• vomiting

Smaller cysts can be asymptomatic and only found incidentally at any time. 

Pathology

The duplicated segment has a thick wall of smooth muscle and is lined with alimentary tract mucosa. The lining mucosa may be the same as that in the segment it parallels, or it may be similar to that in some other portions of the alimentary tract, frequently gastric mucosa, in which case peptic ulceration of the duplication is a common finding.

Radiographic features

Most often, duplications are spherical cysts that rarely make an impression on the oesophagus and are usually located in the right hemithorax.

Plain film

On plain chest radiographs, they are usually seen as rounded fluid / soft tissue density posterior mediastinal masses.

Fluoroscopy / Barium swallow

In cystic esophageal duplication, the oesophagogram shows the esophagus to be displaced to the side opposite the mass.

CT

Duplication cysts appear as is sharply marginated masses with homogeneous fluid density. No enhanced after intravenous contrast administration is visible.

MRI

MRI demonstrates features of a cyst: Signal characteristics therefore include.:

• T1: - low-low signal
• T2: - high-high signal
• T1 C+ (Gd): - no-no solid enhancement

Differential diagnosis

For a partial cystic duplication consider any posterior or middle mediastinal mass, including: 

• neoplasms arising from the sympathetic chain: ganglioglioma, ganglioneuroma etc... 
• bronchogenic cyst:
  • the distinction between this entity and a oesophagealesophageal duplication cysts is often not possible on imaging, and only is settled in the unusual setting of histology being obtained
  • furthermore, in asymptomatic patients the distinction is of no real clinical relevance
• pericardial cyst
• neurenteric cyst
• pulmonary sequestration
• anterior meningocoele
• haemangioma