Retroperitoneal bronchogenic cyst: CT and MR imaging.

Retroperitoneal bronchogenic cysts are extremely rare congenital anomalies that represent malformations of the embryonic foregut and are morphologically expressed as maldevelopments of the respiratory system. Because of the low prevalence of these tumors, their imaging features have seldom been described. We present the computed tomographic and magnetic resonance imaging findings of a case of retroperitoneal bronchogenic cyst.