High-riding superior pericardial recess: temporal change can help distinguish from mediastinal pathology.

A high-riding superior pericardial recess is an infrequently encountered normal variant which may mimic mediastinal pathology. We present a patient in whom a high-riding superior pericardial recess could confidently be diagnosed on a neck CT due to its change in size and shape demonstrated on a chest CT which was done 4 minutes later.