 Brain parenchyma appears within normal limits. There is no diffusion abnormality. There are no areas of abnormal signal or pathological enhancement. The ventricles and sulci are within normal limits. No hydrocephalus. There is no midline shift or mass effect. No extra-axial fluid collection is identified.Normal flow-voids are demonstrated in the major intracranial vascular structures. There is mucosal thickening in the sphenoid sinuses. There is mild mucosal thickening in the bilateral mastoid air cells.MRI pituitary gland: Dedicated images through the sella demonstrate a T1 isointense and T2 mildly hyperintense lesion measuring approximately 8x 6 mm in axial dimension and 7 mm in craniocaudal dimension, involving the left aspect of the suprasellar cistern just above the pituitary gland. There is no significant enhancement associated with it. This lesion is just lateral to the infundibulum and abuts the left aspect of the chiasm/prechiasmatic optic nerve without mass effect. The pituitary gland demonstrates preserved T1 hyperintensity involving the neurohypophysis and homogeneous enhancement. No focal abnormal signal intensity or mass is seen within the pituitary gland. The pituitary stalk lies in the midline. The optic chiasm, cavernous sinuses appear unremarkable. There is diffuse opacification of the bilateral sphenoid sinuses, which is increased since prior study from October 20, 2015.
1. 8 x 6 mm nonenhancing lesion involving the left aspect of the suprasellar cistern just above the pituitary gland. Differential is broad and includes benign cystic lesion (such as suprasellar Rathke's cleft cyst or epidermoid cyst) or hamartoma; neoplastic lesion can not be entirely excluded although lack of enhancement makes this less likely. Would suggest continued follow-up. There is no appreciable mass effect on the optic chiasm.2. The brain parenchyma is otherwise unremarkable.