Pericardial cyst

  • due to persistence of blind ending ventral parietal pericardial recesses
  • cyst that communicates with pericardial space – pericardial diverticula
  • well defined
  • oval or occasionally lobulated
  • right cardiophrenic angle (70%)
  • left cardiophrenic angle (20%)
  • sometimes higher up in mediastinum
  • clear fluid
  • MR: low to intermediate on T1, high on T2 with no post Gado enhancement