The ultrasound appearance of an unusual fetal pericardial cyst.

We describe the prenatal and postnatal sonographic findings and postnatal course in the first reported patient with a posterior mediastinal pericardial cyst. We then review and discuss current knowledge about the management of prenatally diagnosed cystic structures of the pericardium. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:149-151, 2018.