Follow up of a pituitary lesion. There is a cystic lesion within the sella that measures up to 10 mm in height and contains a globular focus of T1 hyperintensity. The pituitary gland is distorted by the lesion, but there is no mass effect upon the optic apparatus or cavernous sinuses. There is an enlarged retrocerebellar cerebrospinal fluid signal space.
1. A cystic lesion within the sella may represent a Rathke cyst or cystic adenoma that contains subacute hemorrhage.2. An enlarged retrocerebellar cerebrospinal fluid signal space may represent an arachnoid cyst.