Cysts of the Mediastinum

Mediastinal cysts are fluid-filled lesions surrounded by a thin wall with an epithelial lining. These cysts are typically congenital, account for approximately 15-20% of all mediastinal masses, and may be found in any mediastinal compartment. Although mediastinal cysts may be initially detected on chest radiography, these lesions are optimally evaluated with computed tomography (CT) or magnetic resonance imaging (MRI). Cysts typically manifest as well-circumscribed, spherical lesions of water attenuation or signal, buy may appear heterogeneous when complicated by hemorrhage or infection. A focused differential diagnosis may be generated based on lesion location. For instance, bronchogenic cysts are most common in the middle mediastinum and pericardial cysts are typically found in the right cardiophrenic angle. Other mediastinal cysts include esophageal duplication and neurenteric cyst. Although meningocele is not a true cyst, it exhibits a cystic appearance on imaging.