Duplication of the esophagus has a range of macroscopic appearances, ranging from complete (which is very rare) to partial cystic duplication (esophageal duplication cyst). It is the second most common gastrointestinal tract duplication after that of the ileum.
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.
Presentation of large duplication cysts is usually in the newborn or infant, with symptoms referable to pressure on the adjacent lung or esophagus, leading to:
- respiratory difficulties
Smaller cysts can be asymptomatic and only found incidentally at any time.
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.
Most often, duplications are spherical cysts that rarely make an impression on the esophagus and are usually located in the right hemithorax.
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 esophagogram shows the esophagus to be displaced to the side opposite the mass.
Duplication cysts appear as is sharply marginated masses with homogeneous fluid density. No enhanced after intravenous contrast administration is visible.
MRI demonstrates features of a cyst: Signal characteristics therefore include:
- T1: -low signal
- T2: -high signal
- T1 C+ (Gd): -no solid enhancement
For a partial cystic duplication consider any posterior or middle mediastinal mass, including:
- neoplasms arising from the sympathetic chain: ganglioglioma, ganglioneuroma etc.
- the distinction between this entity and a esophageal 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