Bronchogenic cyst masquerading as a chronic post-traumatic pseudoaneurysm of the aortic isthmus.

The serious nature of false aneurysms that develop in the aortic isthmus after blunt chest trauma is well known. The authors describe the case of a 33-year-old woman who presented with symptoms of chronic post-traumatic pseudoaneurysm of the aorta 3 months after blunt chest trauma. Radiologic investigations could not substantiate an aortic disruption. A bronchogenic cyst masquerading as a false aneurysm of the aorta was identified at thoracotomy. Bronchogenic cysts are one of the most common causes of primary mid-mediastinal masses and should be considered as potential causes of mid-mediastinal enlargement. However, this consideration should not delay urgent surgery if vascular damage cannot be ruled out.