Foregut duplications in the superior mediastinum: beware of a common wall with the tracheo-bronchial tree

Background: Foregut duplication cysts (FD) with a common muscular wall with the oesophagus are well recognised. Our case series highlights the existence of a common wall between superior mediastinal FD and the tracheo-bronchial tree.

Materials and methods: Over the last 15 years, we have thoracoscopically resected 41 FD. Five cases were identified to have a common wall with the tracheo-bronchial tree at operation. The clinical history, radiology, findings at operation and pathology were evaluated to highlight learning points.

Results: Five superior mediastinal cysts with a common wall were identified, with two antenatally and three postnatally diagnosed. All three postnatal cases and one antenatal case presented with symptoms of respiratory compromise and stridor. Only one neonate was relatively asymptomatic before resection. CT similarities in all cases were: separation of trachea and oesophagus by the cyst, oesophageal deviation to the right or compression and compression of trachea/bronchus. Thoracoscopically, two cysts were resected without injury to the airway, while three had inadvertent tracheo-bronchial injury. Repair of the tracheal injury was possible in one case thoracoscopically, while two cases required conversions, as adequate oxygenation could not be maintained despite on-table endotracheal tube advancement beyond the injury and thoracoscopic manoeuvres. All cases had excellent outcomes at follow-up (median 25months, range 4-39months) with resolution of symptoms and no recurrences.

Conclusions: Our report highlights the existence of a common wall between the superior mediastinal FD and the tracheo-bronchial tree. Thoracoscopic resections are feasible including repair of inadvertent airway injury, provided adequate oxygenation can be maintained.